Systemic MIF facilitates chronic lymphocytic leukemia development independent of its cellular source

Systemic MIF facilitates chronic lymphocytic leukemia development independent of its cellular source | bioRxiv /* */ /* */ <!-- <!-- /*! * yepnope1.5.4 * (c) WTFPL, GPLv2 */ (function(a,b,c){function d(a){return"[object Function]"==o.call(a)}function e(a){return"string"==typeof a}function f(){}function g(a){return!a||"loaded"==a||"complete"==a||"uninitialized"==a}function h(){var a=p.shift();q=1,a?a.t?m(function(){("c"==a.t?B.injectCss:B.injectJs)(a.s,0,a.a,a.x,a.e,1)},0):(a(),h()):q=0}function i(a,c,d,e,f,i,j){function k(b){if(!o&&g(l.readyState)&&(u.r=o=1,!q&&h(),l.onload=l.onreadystatechange=null,b)){"img"!=a&&m(function(){t.removeChild(l)},50);for(var d in y[c])y[c].hasOwnProperty(d)&&y[c][d].onload()}}var j=j||B.errorTimeout,l=b.createElement(a),o=0,r=0,u={t:d,s:c,e:f,a:i,x:j};1===y[c]&&(r=1,y[c]=[]),"object"==a?l.data=c:(l.src=c,l.type=a),l.width=l.height="0",l.onerror=l.onload=l.onreadystatechange=function(){k.call(this,r)},p.splice(e,0,u),"img"!=a&&(r||2===y[c]?(t.insertBefore(l,s?null:n),m(k,j)):y[c].push(l))}function j(a,b,c,d,f){return q=0,b=b||"j",e(a)?i("c"==b?v:u,a,b,this.i++,c,d,f):(p.splice(this.i++,0,a),1==p.length&&h()),this}function k(){var a=B;return a.loader={load:j,i:0},a}var l=b.documentElement,m=a.setTimeout,n=b.getElementsByTagName("script")[0],o={}.toString,p=[],q=0,r="MozAppearance"in l.style,s=r&&!!b.createRange().compareNode,t=s?l:n.parentNode,l=a.opera&&"[object Opera]"==o.call(a.opera),l=!!b.attachEvent&&!l,u=r?"object":l?"script":"img",v=l?"script":u,w=Array.isArray||function(a){return"[object Array]"==o.call(a)},x=[],y={},z={timeout:function(a,b){return b.length&&(a.timeout=b[0]),a}},A,B;B=function(a){function b(a){var a=a.split("!"),b=x.length,c=a.pop(),d=a.length,c={url:c,origUrl:c,prefixes:a},e,f,g;for(f=0;f<d;f++)g=a[f].split("="),(e=z[g.shift()])&&(c=e(c,g));for(f=0;f<b;f++)c=x[f](c);return c}function g(a,e,f,g,h){var i=b(a),j=i.autoCallback;i.url.split(".").pop().split("?").shift(),i.bypass||(e&&(e=d(e)?e:e[a]||e[g]||e[a.split("/").pop().split("?")[0]]),i.instead?i.instead(a,e,f,g,h):(y[i.url]?i.noexec=!0:y[i.url]=1,f.load(i.url,i.forceCSS||!i.forceJS&&"css"==i.url.split(".").pop().split("?").shift()?"c":c,i.noexec,i.attrs,i.timeout),(d(e)||d(j))&&f.load(function(){k(),e&&e(i.origUrl,h,g),j&&j(i.origUrl,h,g),y[i.url]=2})))}function h(a,b){function c(a,c){if(a){if(e(a))c||(j=function(){var a=[].slice.call(arguments);k.apply(this,a),l()}),g(a,j,b,0,h);else if(Object(a)===a)for(n in m=function(){var b=0,c;for(c in a)a.hasOwnProperty(c)&&b++;return b}(),a)a.hasOwnProperty(n)&&(!c&&!--m&&(d(j)?j=function(){var a=[].slice.call(arguments);k.apply(this,a),l()}:j[n]=function(a){return function(){var b=[].slice.call(arguments);a&&a.apply(this,b),l()}}(k[n])),g(a[n],j,b,n,h))}else!c&&l()}var h=!!a.test,i=a.load||a.both,j=a.callback||f,k=j,l=a.complete||f,m,n;c(h?a.yep:a.nope,!!i),i&&c(i)}var i,j,l=this.yepnope.loader;if(e(a))g(a,0,l,0);else if(w(a))for(i=0;i (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0];var j=d.createElement(s);var dl=l!='dataLayer'?'&l='+l:'';j.src='//www.googletagmanager.com/gtm.js?id='+i+dl;j.type='text/javascript';j.async=true;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-M677548'); Skip to main content Home About Submit ALERTS / RSS Search for this keyword Advanced Search New Results Systemic MIF facilitates chronic lymphocytic leukemia development independent of its cellular source Viktoria Kohlhas , Nina Reinart , Natascha Rosen , Sebastian Reinartz , View ORCID Profile Phuong-Hien Nguyen , Michael Hallek doi: https://doi.org/10.1101/2025.02.22.639632 Viktoria Kohlhas 1 University of Cologne, Faculty of Medicine and University Hospital Cologne, Department I of Internal Medicine, Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf Find this author on Google Scholar Find this author on PubMed Search for this author on this site Nina Reinart Find this author on Google Scholar Find this author on PubMed Search for this author on this site Natascha Rosen Find this author on Google Scholar Find this author on PubMed Search for this author on this site Sebastian Reinartz Find this author on Google Scholar Find this author on PubMed Search for this author on this site Phuong-Hien Nguyen Find this author on Google Scholar Find this author on PubMed Search for this author on this site ORCID record for Phuong-Hien Nguyen For correspondence: michael.hallek{at}uni-koeln.de hien.nguyen{at}uk-koeln.de Michael Hallek Find this author on Google Scholar Find this author on PubMed Search for this author on this site For correspondence: michael.hallek{at}uni-koeln.de hien.nguyen{at}uk-koeln.de Abstract Full Text Info/History Metrics Supplementary material Preview PDF Abstract Macrophage migration inhibitory factor (MIF) is broadly produced by various cell types, particularly immune cells, and functions as a key modulator of innate and adaptive immunity. Increasing evidence has linked MIF to the pathogenesis of both solid tumors and hematologic malignancies, including chronic lymphocytic leukemia (CLL). We previously showed that the global deletion of Mif in the TCL1 transgenic mouse model for CLL significantly delayed disease development leading to longer overall survival of the knockout mice. In this study, we demonstrated that adaptive transfer of murine CLL cells failed to establish disease in Mif-deficient recipients due to impaired homing of leukemic cells into the spleens, indicating that host-derived Mif is essential for leukemic infiltration and expansion. To identify the most relevant source of Mif in CLL, we generated two CLL mouse strains with B-lymphoid- or myeloid-lineage-specific Mif deletion. In contrast to the global Mif knockout, neither conditional Mif knockout significantly altered CLL progression, illustrating that the cellular source of Mif is less critical than its systemic presence in the tissue environment. Taken together, these in vivo findings indicate that MIF plays a relevant role in CLL pathogenesis, acting independently of its specific cellular origin. Highlights CLL cells failed to establish disease in Mif-deficient hosts due to impaired tissue homing Conditional deletion of Mif in B lymphoid- or myeloid cells did not significantly impact CLL progression in vivo Systemic MIF is critical for CLL pathogenesis, independent of its cellular source Introduction Since the discovery of macrophage migration inhibitory factor (MIF) as the first cytokine to inhibit the migration of macrophages ( Bloom and Bennett 1966 ; David 1966 ), MIF has been shown to be a pleiotropic modulator of innate and adaptive immune responses. MIF is produced and released by almost all cell types, including macrophages (T. Calandra et al. 1994 ), monocytes ( Flieger et al. 2003 ), T and B lymphocytes ( Bacher et al. 1996 ), eosinophils ( Rossi et al. 1998 ), neutrophils ( Daryadel et al. 2006 ) and mast cells (H. Chen et al. 1998 ). Binding of MIF to its receptor, the CD74-CD44 complex, activates the MAPK-ERK and PI3K-AKT pathways and induces NFκB activation and production of pro-inflammatory target genes, promoting cell survival and inhibiting apoptosis ( Leng et al. 2003 ; Shi et al. 2006 ); (Thierry Calandra and Roger 2003 ). MIF also binds to chemokine receptors, including CXCR2, CXCR4, and CXCR7, thereby stimulating cell migration, chemotaxis, and immune responses ( Bernhagen et al. 2007 ; Weber et al. 2008 ; Alampour-Rajabi et al. 2015 ). MIF activates monocytes and macrophages and optimizes their expression of TNF-α, IL-1, and PGE2 ( Brennan-Bourdon et al. 2015 ; Cao et al. 2005 ; Yaddanapudi et al. 2016 ). In B cells, activation of the surface receptor complex CD74/CD44 by MIF induces the production of IL-8 and increases the resistance to apoptosis via upregulation of BCL-2 ( Binsky et al. 2007 ; Gore et al. 2008 ). MIF may also influence other pathways, such as TP53 ( Fingerle-Rowson et al. 2003 ; Jung, Seong, and Ha 2008 ) and JAB1-AP1 ( Kleemann et al. 2000 ). MIF plays a significant role as a proinflammatory and immuno-regulatory cytokine during inflammatory responses, both under physiological and pathological conditions such as infectious- and autoimmune diseases ( Calandra et al. 1994 ; Kang and Bucala 2019; Sumaiya et al. 2022). Mif-knockout mice develop without apparent deficits under laboratory conditions ( Fingerle-Rowson et al. 2003 ). Upon pathogen challenge, Mif-knockout mice exhibit alleviated inflammatory responses and improved outcomes due to protection against cytokine storms and organ damage ( Bozza et al. 1999 ; Smith et al. 2019 ; Jinhong Li et al. 2018 ; Koebernick et al. 2002 ), underscoring its role in modulating the magnitude of the immune response. Given the role of MIF in inflammation and putative signaling related to tumorigenesis, there is a growing recognition that MIF is involved in the pathogenesis of various cancers ( Bucala and Donnelly 2007 ); ( Valdez et al. 2024 ), including solid tumors like non-small cell lung cancer ( Howard et al. 2004 ), prostatic adenocarcinoma ( Meyer-Siegler and Hudson 1996 ), bladder cancer ( Taylor et al. 2007 ), hepatocellular carcinoma ( Liao et al. 2023 ) and melanoma ( Tanese and Ogata 2024 ); as well as in several hematologic malignancies including myeloproliferative neoplasm ( Pritchard et al. 2024 ), acute myeloid leukemia ( Spertini et al. 2024 ) B cell lymphoma ( Talos et al. 2005 ), and chronic lymphocytic leukemia (CLL) ( Reinart et al. 2013 ). In most malignant conditions, MIF has been characterized as a tumor-promoting factor that regulates both intrinsic oncogenic signaling pathways within tumor cells and the composition and dynamics of the tumor immune microenvironment ( Valdez et al. 2024 ). CLL is the most frequent leukemia in the Western Hemisphere. It is a monoclonal B-cell disorder characterized by the expansion and accumulation of morphologically mature but functionally impaired lymphocytes ( Hallek et al. 2018 ). The apoptosis resistance and survival of CLL cells depend highly on interactions with the tumor microenvironment (TME), rendering it a disease “addicted to the host” (Jan A. Burger and Gribben 2014 ). In CLL, the TME comprises cellular components such as macrophages, fibroblasts, T cells, and soluble molecules like chemokines and cytokines (Vom Stein, Hallek, and Nguyen 2023; Jestrabek et al. 2024 ). When intercrossed with the TCL1 mouse model for CLL ( Bichi et al. 2002 ; Koch et al. 2020 ), Mif-knockout CLL mice showed a delayed onset of leukemia, reduced splenomegaly and hepatomegaly, and a significantly prolonged survival than TCL1 tg/wt controls ( Reinart et al. 2013 ). Mif-deficient CLL cells were more susceptible to apoptosis in vitro . By using neutralizing anti-Mif antibodies, the survival of CLL cells was drastically reduced on a macrophage feeder layer. The number of macrophages was significantly reduced in the spleen and bone marrow of TCL1 tg/wt Mif -/- mice. Additionally, the migratory activity of TCL1 tg/wt Mif -/- macrophages decreased in comparison to TCL1 tg/wt Mif wt/wt macrophages. These results indicated that MIF supported the development of CLL in vivo by enhancing the interaction of CLL cells with macrophages. In CLL patient samples, MIF mRNA and protein levels were significantly increased in CLL cells compared to B cells of healthy donors. Additionally, MIF plasma levels were strongly elevated ( Reinart et al. 2013 ). The MIF receptors CXCR4 and CD74 are upregulated on CLL cells and are pivotal for leukemic cell viability and migration, cooperatively promoting the survival and homing of CLL cells upon MIF stimulation (J. A. Burger, Burger, and Kipps 1999 ; Binsky et al. 2006 ; Thavayogarajah et al. 2022 ). Although CD74 appears to be dispensable for CLL progression in the TCL1 mouse model ( Barthel et al. 2020 ), the absence of its coreceptor CD44 results in a longer survival of CLL-diseased mice via MCL1 modulation ( Fedorchenko et al. 2013 ), suggesting that Mif exerts its leukemia-promoting effects at least in part through this complex in vivo . As MIF is a broadly expressed cytokine, it remains unclear which cell type is relevant for the secretion and the disease-promoting effects of MIF in CLL. To address this question, we generated two mouse strains with B lymphoid- and myeloid-lineage-specific deletion of Mif to identify the relevant source of MIF in CLL. Materials and Methods Mice All mouse studies were approved by the state authorities of North Rhine-Westphalia, Germany (Landesamt für Natur-, Umwelt-und Verbraucherschutz Nordrhein-Westfalen (LANUV)), approvals #84-02.04.2014.A146 #81-02.04.2019.A009 and #84-02.04.2016.A058. Eµ-TCL1 transgenic mice ( Bichi et al. 2002 ) were crossed with Mif fl/fx mice ( Brocks et al. 2017 ). For conditional Mif knockout in B cells and myeloid lineage, Eµ-TCL1 tg/wt Mif fl/fl mice were crossed with either CD19 cre/wt ( Rickert, Roes, and Rajewsky 1997 ) or LysM cre/wt ( Clausen et al. 1999 ) mice, respectively. Husbandry, procedures for blood and tissue sample collection, determination of overall survival, and differential blood counts were performed as described previously ( Nguyen et al. 2016 ; Kohlhas, Hallek, and Nguyen 2020 ). RNA-isolation and quantitative RT-PCR RNA was isolated using Trizol reagent (Invitrogen). Reverse transcription was performed with the ProtoScriptII-First Strand cDNA Synthesis Kit (New England Biolabs). Quantitative real-time PCR for MIF was run on a Light Cycler 480 system (Roche Diagnostics) using TaqMan Fast Universal PCR Master Mix (Applied Biosystems (ThermoFisher Scientific). mRNA levels were normalized to peptidylprolyl isomerase A (PPIA). Primer: Mm02342430_g1 Ppia FAM PN4453320, Mm01611157_gH Mif, Gm163+ FAM PN4453320 Fluorescence-activated cell sorting (FACS) Splenocytes of five wild type (C57BL/6) mice were sorted by FACS into T cells (CD3-pacific blue), NK cells (NK1.1-Alexa Fluor 488), B cells (CD19-APC-Cy7), macrophages (F4/80-PE), and endothelial cells (CD146-APC). Syngeneic transplantation of murine CLL cells Transplantation of murine CLL cells was previously described ( Nguyen et al. 2016 ; Koch et al. 2020 ). All donor- and recipient mice were backcrossed for over 10 generations to a C57BL/6J genetic background. Freshly homogenized and filtered splenocytes from moribund Eµ-TCL1 mice were layered with the Lymphocyte Separate Medium (PAA), followed by centrifugation and separation of interphase-concentrated mononuclear cells. After several washing steps, CLL cells were viable, frozen at -150 °C, and thawed upon transplantation. Eµ-TCL1 CLL cells were thawed and injected intraperitoneally into age- and sex-matched WT (n = 6) and Mif -/- (n = 9) mice. Blood was drawn every 2 weeks and analyzed for CD5 + CD19 + positive cells to monitor CLL development. In vivo short-term homing assay Isolated Eµ-TCL1 CLL cells (n = 2) were stained with CFSE (5 µM, Abcam) and injected into sex-matched WT (n = 4) and Mif -/- (n = 4) recipients intravenously. After 3 hours, mice were sacrificed, and splenocytes and bone marrow cells were isolated. Fc-Receptor was blocked with FcR Blocking Reagent (Miltenyi Biotec), and leukocytes were stained with an anti-CD45-VioBlue (Miltenyi Biotec) antibody. For intracellular staining of TCL1 (TCL1(human)-Alexa Fluor 647), the IntraPrep Permeabilization Reagent Kit (Beckman Coulter) was used according to the manufacturer’s instructions. Labeled samples were run on a MACSQuant X (Miltenyi Biotec) flow cytometer, and data were analyzed using Kaluza 2.0 Flow Analysis Software (Beckman Coulter). Results Global Mif deletion in the TCL1 tg/wt mice resulted in a significantly delayed development of CLL due to defective homing of CLL cells to the lymphoid organs essential for leukemic cell expansion ( Reinart et al. 2013 ). To determine whether the absence of Mif in the tumor microenvironment impaired CLL development, TCL1 tg/wt CLL cells were transplanted into wild type (WT) or Mif -/- mice, and CLL development was monitored in recipients over 21 weeks. While WT animals showed an increasing number of CLL cells in peripheral blood, almost no CLL cells could be detected in the peripheral blood of Mif -/- animals throughout the monitoring time ( Fig. 1A ). The median survival of transplanted WT mice was 139 days, whereas none of the transplanted Mif -/- recipients succumbed to leukemia and did not reach the defined endpoint for this experiment ( Fig. 1B ). Because homing of transplanted CLL cells to lymphoid organs such as the spleen is crucial for outgrowth of leukemia cells in recipient mice, we tested if CLL cells could migrate to the spleens in short-term homing assays. TCL1 CLL cells were transplanted into WT and Mif -/- recipients, and after 3 h, the homing of CLL cells into the spleen was measured via flow cytometry of the TCL1 transgene. Interestingly, the number of CLL cells was reduced in Mif -/- recipients ( Fig. 1C ). These results confirmed our hypothesis that a Mif deficient microenvironment failed to recruit CLL cells into the lymphoid homing organs, thereby preventing CLL growth. Download figure Open in new tab Figure 1. Mif is a critical cytokine for leukemia engraftment in the CLL adoptive transfer model. A: Flow cytometric analysis of CD19 + CD5 + CLL cells in the peripheral blood of WT and Mif -/- recipients after syngeneic transplantation of TCL1 tg/wt CLL cells. B: Survival of CLL-transplanted WT and Mif -/- mice. Mif -/- recipients did not reach the primary endpoint. C: Homing of CLL cells in spleens of WT and Mif -/- 3 h after transplantation of TCL1 tg/wt CLL cells. D: Relative Mif RNA expression in isolated cell types of wild type mice. FACS-sorted B cells (CD19), T cells (CD3), endothelial cells (CD146), macrophages (F4/80), and NK cells (NK1.1) from murine spleens were subjected to qRT-PCR. To uncover the cellular source of Mif in the CLL microenvironment, gene expression of Mif was determined in different purified cell types from the spleens of WT C57BL/6 mice. B cells (CD19 + ), T cells (CD3 + ), endothelial cells (CD146 + ), macrophages (F4/80 + ), and NK cells (NK1.1 + ) were harvested and sorted from murine spleens based on their surface marker expression by FACS. Mif was found to be expressed in all cell types using qRT-PCR. The highest expression was found in macrophages (relative expression: 1.192), followed by NK cells (1.183) and B cells (1.175). A lower expression was detected in T cells (1.168) and the lowest in endothelial cells (1.129) ( Fig. 1D ). As Mif was shown to be elevated in CLL cells and highly expressed in the B cell compartment, we sought to determine if Mif expression in the leukemic B cells would be critical for disease development. For this purpose, we generated B cell-specific Mif knockout mice by intercrossing Mif fl/fl mice with TCL1 tg/wt and CD19 cre/wt mice to obtain a B cell-specific Mif knockout ( TCL1 tg/wt CD19 cre/wt Mif fl/fl ) ( Fig. 2A ) and monitored CLL development in blood samples of TCL1 tg/wt CD19 wt/wt Mif fl/fl (referred to as TCL1 tg/wt ) and TCL1 tg/wt CD19 cre/wt Mif fl/fl mice over 12 months. In contrast to the significantly delayed CLL progression observed in global Mif -/- mice, we observed only moderate reductions of the leukocyte counts of TCL1 tg/wt CD19 cre/wt Mif fl/fl at month 9 and month 12 ( Fig. 2B ). In line with these findings, CLL burden determined by the percentage of CD5 + CD19 + cells in PBMC ( Fig. 2C ) and CLL count per µl blood ( Fig. 2D ) showed no significant differences in the B cell-specific Mif knockout compared to controls. There was only a non-significant trend of a lower CLL burden at month 6, suggesting a slight delay in disease progression at the early stage. Additionally, no differences in the weight of spleens (1.57 gr vs. 1.81 gr) and livers (3.54 gr vs.2.97 gr) were observed between both genotypes ( Fig. 2E ). The B cell-specific Mif knockout did not affect the overall survival of mice without CLL burden, as WT mice lived 827 days (n = 10) and CD19 cre/wt Mif fl/fl lived 878 days (n = 19) on average. Mice with the TCL1 transgene lived significantly shorter, as expected. However, no significant difference in the overall survival between TCL1 tg/wt (430 days, n = 10) and TCL1 tg/wt CD19 cre/wt Mif fl/fl (402 days, n = 22) was observed ( Fig. 2F ). Download figure Open in new tab Figure 2. TCL1 tg/wt CD19 cre/wt Mif fl/fl mice show no clear difference in CLL burden compared with TCL1 tg/wt mice. A: Schematic overview of the breeding strategy to establish the TCL1 tg/wt CD19 cre/wt Mif fl/fl mouse strain. B: Count of leukocytes in 1 µl blood of TCL1 tg/wt and TCL1 tg/wt CD19 cre/wt Mif fl/fl over one year. C: Flow cytometric analysis of CD19 + CD5 + CLL cells in the peripheral blood of TCL1 tg/wt and TCL1 tg/wt CD19 cre/wt Mif fl/fl mice over one year. D: Count of CLL cells in 1 µl blood of TCL1 tg/wt and TCL1 tg/wt CD19 cre/wt Mif fl/fl over one year. E: Spleen and liver weights of age-matched and moribund TCL1 tg/wt and TCL1 tg/wt CD19 cre/wt Mif fl/fl mice. F: Kaplan-Meier curves representing the overall survival of WT, Mif fl/fl , TCL1 tg/w t , TCL1 tg/wt CD19 cre/wt Mif fl/fl mice from birth to moribund. The lacking effect of Mif depletion in B-CLL cells prompted us to examine the impact of Mif depletion in other cell types of the microenvironment. As Mif showed the highest expression in macrophages, and we had observed that a reduction of macrophages in TCL1 tg/wt Mif -/- hindered CLL expansion ( Reinart et al. 2013 ), we crossed the TCL1 tg/wt Mif fl/fl mice with LysM cre/wt mice, which express the Cre recombinase under the control of the myeloid cell-specific lysozyme 2 gene to generate a myeloid-derived cell-specific conditional knockout ( Clausen et al. 1999 ) ( Fig. 3A ). Again, we monitored CLL burden in TCL1 tg/wt LysM cre/wt Mif fl/fl and control mice over 12 months of age. We did not detect any differences in leukocyte count ( Fig. 3B ), as well as no differences in the parameters reflecting the CLL development in the peripheral blood in the conditional macrophage knockout of Mif ( Fig. 3C ). Additionally, we did not detect significant differences in the weight of spleens (1.867 g versus 0.785 g) and livers (2.73 g versus 2.111 g) between TCL1 tg/wt and TCL1 tg/wt LysM cre/wt Mif fl/fl ( Fig. 3D ). The overall survival of CLL mice was not affected by the conditional knockout, as TCL1 tg/wt mice lived 436 days (n = 27) and TCL1 tg/wt LysM cre/wt Mif fl/fl mice lived 397 days (n = 26) on average ( Fig. 3E ). Finally, we also did not observe any differences in the percentage of myeloid cells or monocytes in the peripheral blood of LysM cre/wt and TCL1 tg/wt LysM cre/wt Mif fl/fl and their respective controls, WT or TCL1 tg/wt (Supplemental Fig. 1A & B). Overall, the macrophage-specific deletion of Mif did not influence the development or progression of CLL in the TCL1 tg/wt LysM cre/wt Mif fl/fl mouse model. Download figure Open in new tab Fig. 3 TCL1 tg/wt LysM cre/wt Mif fl/fl mice show no difference in CLL burden compared with TCL1 tg/wt mice. A: Schematic overview of the breeding strategy to establish the TCL1 tg/wt LysM cre/wt Mif fl/fl mouse strain. B: Count of Leukocytes in 1 µl blood of TCL1 tg/wt and TCL1 tg/wt LysM cre/wt Mif fl/fl over one year. C: Flow cytometric analysis of CD19 + CD5 + CLL cells in the peripheral blood of TCL1 tg/wt and TCL1 tg/wt LysM cre/wt Mif fl/fl mice over one year. D: Spleen and liver weights of age-matched, moribund TCL1 tg/wt and TCL1 tg/wt LysM cre/wt Mif fl/fl mice. E: Kaplan-Meier curves representing the overall survival of TCL1 tg/wt and TCL1 tg wt LysM cre/wt Mif fl/fl mice from birth to moribund. Discussion We previously showed that the absence of the cytokine Mif delayed leukemia development in the TCL1 mouse model for CLL ( Reinart et al. 2013 ). Mif knockout reduced the survival of CLL cells and the number of macrophages in all typical homing organs of CLL cells. In this study, we demonstrated that CLL cells from TCL1 mice failed to home to the spleens of Mif -/- recipient mice, resulting in a lack of CLL outgrowth in these knockout animals. These findings formally confirm that the presence of Mif in the host is highly relevant to recruit CLL cells to the homing organs – a prerequisite for leukemic cell survival and growth. In contrast, there was no significant difference in CLL progression in mice deficient of Mif in B cells or the myeloid lineage. The phenotypes of these two conditional Mif knockout mouse models illustrate that the cellular source of Mif is less critical than the systemic presence of Mif in the tissue environment for CLL development. CLL cells are highly dependent on various stimuli from their tumor microenvironment, and neither a single cell type nor a soluble factor alone can fully confer malignant potential to CLL cells. Notwithstanding, several cytokines, including CXCL13, BAFF, APRIL, and MIF, have been shown to play crucial roles in CLL initiation and progression ( Ullah et al. 2024 ; J. A. Burger, Burger, and Kipps 1999 ; Vom Stein, Hallek, and Nguyen 2023). Our in vivo transplantation experiment and homing assay underscore the critical role of MIF in recruiting leukemic cells to their homing organs, such as the spleen. Given that the splenic environment in the TCL1 mouse model mimics the lymph nodes in CLL patients ( Collard et al. 2022 ) – the primary sites for CLL cell proliferation ( Mittal et al. 2014 ) – these findings indicate an essential role of MIF in leukemic cell homing and disease development. MIF is a ubiquitous cytokine stored in intracellular pools and released by various cell types. Our analysis validates its presence across all cell types in mice, with higher expression in immune cells compared to endothelial cells. The highest expression of Mif in macrophages reflects its crucial function in this lineage, regulating macrophage activation, recruitment, and cytokine production. MIF enhances pro-inflammatory responses while countering the anti-inflammatory effects of glucocorticoids (T. Calandra et al. 1995 ). Macrophages lacking MIF exhibit reduced activation and migration, dampening immune responses — a beneficial effect in chronic inflammatory diseases (Thierry Calandra and Roger 2003 ; Thiele, Donnelly, and Mitchell 2022 ). In cancer, MIF drives macrophage polarization into immunosuppressive, pro-tumorigenic M2-like tumor-associated macrophages (TAMs), which secrete IL-10 and TGF-β while promoting angiogenesis, tumor cell migration, and immune suppression. MIF also facilitates macrophage recruitment to the vicinity of tumors, supporting disease progression. In CLL, global Mif knockout reduces macrophage recruitment to the spleen and bone marrow ( Reinart et al. 2013 ), yet macrophage-specific Mif knockout does not affect disease progression. This observation corroborates that CLL establishment requires the mere presence of Mif, independently of its cellular source. Although we have not investigated the potential influence of Mif depletion in other cell types, such as T cells or NK cells, it seems unlikely that deleting the Mif gene in further individual cell types can recapitulate the strong effects observed in the global Mif knockout background. In healthy B cells, MIF promotes survival, activation, and proliferation during immune processes. However, MIF production becomes dysregulated in CLL, and leukemia cells rely on autocrine MIF signaling, activating NF-κB and BCL2 survival pathways via the CD74 receptor ( Binsky et al. 2007 ; Gore et al. 2008 ). This intrinsic role of MIF may partially account for the delayed disease progression observed at earlier stages in the B cell specific Mif knockout mice, albeit not significant. Notwithstanding, the lack of Mif production in leukemic B cells alone was insufficient to hinder CLL development, illustrating that soluble Mif released by non-leukemic cells can also efficiently activate the Mif signaling cascade. Unlike solid tumors, where MIF drives local tumor proliferation and immune dysfunction ( Wirtz et al. 2021 ), CLL’s dispersed nature diminishes the impact of autocrine signaling, making systemic MIF more critical. This systemic influence contrasts with hepatocellular carcinoma, where targeting MIF in hepatocytes reduces tumor growth ( Wirtz et al. 2021 ). Given the high expression of MIF and its receptors in CLL cells, it is likely that the low tissue density and the rapid dispersion of cytokines in the blood and lymphoid organs significantly diminish dependence on autocrine signaling. This could explain why targeting Mif production in individual cell types is less effective in CLL than solid tumors, emphasizing the importance of systemic MIF in the leukemic environment. Given the increasing evidence of MIF’s crucial role in cancer development, MIF has emerged as a promising therapeutic target in various cancers, including CLL. Therapeutic strategies targeting MIF include anti-MIF neutralizing antibodies, MIF antagonists, and small molecule inhibitors. However, MIF presents a challenging target for cancer therapy due to its widespread presence in healthy tissues and circulation. An oxidized form (oxMIF) is linked explicitly with sites of inflammation and solid tumors. Targeting oxMIF with a monoclonal anti-oxMIF antibody showed promising antitumor activity in vitro and in vivo ( Thiele, Donnelly, and Mitchell 2022 ; Rossmueller et al. 2023 ). Recently, novel therapeutic approaches have been developed to inhibit MIF activity selectively. Small-molecule allele-selective transcriptional inhibitor of the MIF immune susceptibility locus was generated, increasing the potential for precision-based MIF inhibitors (Jia Li et al. 2024 ). Furthermore, MIF-directed small molecules have been shown to enhance ferroptosis by impairing DNA repair mechanisms, suggesting a new druggable route for targeting MIF (D. Chen et al. 2024 ). The first development of potent MIF-directed PROTACs (proteolysis-targeting chimeras) has been reported to induce MIF degradation and disrupt its protein-protein interaction network, leading to anti-proliferative activity in lung cancer cells ( Xiao et al. 2021 ). In CLL, targeting the MIF receptor CD74 with milatuzumab has shown potential in clinical trials ( Haran et al. 2018 ). However, a significant challenge in the treatment of CLL remains the limited options for refractory patients. Novel combination therapies targeting the tumor microenvironment are currently considered promising for these cases (Lewis, Vom Stein, and Hallek 2024). Expanding the range of microenvironmental targets could increase potential treatment options for those patients. Taken together, our study shows that MIF plays a relevant role in the development of CLL when present in the microenvironment, regardless of the source of production. In the early stages of disease, the presence of Mif in lymphoid tissues is indispensable for the homing of leukemic cells into the lymphoid organs, where CLL cell survival and proliferation mainly occur. CLL cells can effectively employ Mif signaling in both autocrine and non-autocrine manners. This opens potential avenues for using MIF targeting strategies to treat this leukemia. Author Contribution V.K. analyzed data and wrote the manuscript. N.R. designed and conducted experiments. Na.R., S.R. conducted experiments. P.-H.N. designed experiments, analyzed data, and wrote the manuscript. M.H. initiated, designed, and supervised the study. All authors read, revised, and approved the manuscript. Funding This study was supported by the Deutsche Krebshilfe (DKH, German Cancer Aid) Foundation grant #70112403 to M.H. and by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) grant SFB1530-455784452 (sub-project B01) to M.H. and P.H.N. Declaration of Competing Interests N.R. is currently employed by BeiGene Germany GmbH. S.R. is currently employed by Miltenyi Biotec B.V & Co. KG. These employments are not related to and do not influence the results of this study. The other authors declare no conflict of interest. References ↵ Alampour-Rajabi , Setareh , Omar El Bounkari , Antal Rot , Gerhard Müller-Newen , Françoise Bachelerie , Meinrad Gawaz , Christian Weber , Andreas Schober , and Jürgen Bernhagen . 2015 . “ MIF Interacts with CXCR7 to Promote Receptor Internalization, ERK1/2 and ZAP-70 Signaling, and Lymphocyte Chemotaxis .” FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology 29 ( 11 ): 4497 – 4511 . doi: 10.1096/fj.15-273904 . OpenUrl CrossRef PubMed ↵ Bacher , M. , C. N. Metz , T. Calandra , K. Mayer , J. Chesney , M. Lohoff , D. Gemsa , T. Donnelly , and R. Bucala . 1996 . “ An Essential Regulatory Role for Macrophage Migration Inhibitory Factor in T-Cell Activation .” Proceedings of the National Academy of Sciences of the United States of America 93 ( 15 ): 7849 – 54 . doi: 10.1073/pnas.93.15.7849 . OpenUrl Abstract / FREE Full Text ↵ Barthel , Romy , Oleg Fedorchenko , Tanja Velmans , Natascha Rosen , Phuong-Hien Nguyen , Nina Reinart , Alexandra Florin , Marco Herling , Michael Hallek , and Günter Fingerle-Rowson . 2020 . “ CD74 Is Dispensable for Development of Chronic Lymphocytic Leukemia in Eµ-TCL1 Transgenic Mice .” Leukemia & Lymphoma 61 ( 12 ): 2799 – 2810 . doi: 10.1080/10428194.2020.1791851 . OpenUrl CrossRef PubMed ↵ Bernhagen , Jürgen , Regina Krohn , Hongqi Lue , Julia L. Gregory , Alma Zernecke , Rory R. Koenen , Manfred Dewor , et al. 2007 . “ MIF Is a Noncognate Ligand of CXC Chemokine Receptors in Inflammatory and Atherogenic Cell Recruitment .” Nature Medicine 13 ( 5 ): 587 – 96 . doi: 10.1038/nm1567 . OpenUrl CrossRef PubMed Web of Science ↵ Bichi , Roberta , Susan A. Shinton , Eric S. Martin , Anatoliy Koval , George A. Calin , Rossano Cesari , Giandomenico Russo , Richard R. Hardy , and Carlo M. Croce . 2002 . “ Human Chronic Lymphocytic Leukemia Modeled in Mouse by Targeted TCL1 Expression .” Proceedings of the National Academy of Sciences of the United States of America 99 ( 10 ): 6955 – 60 . doi: 10.1073/pnas.102181599 . OpenUrl Abstract / FREE Full Text ↵ Binsky , Inbal , Michal Haran , Diana Starlets , Yael Gore , Frida Lantner , Nurit Harpaz , Lin Leng , et al. 2007 . “ IL-8 Secreted in a Macrophage Migration-Inhibitory Factor- and CD74-Dependent Manner Regulates B Cell Chronic Lymphocytic Leukemia Survival .” Proceedings of the National Academy of Sciences of the United States of America 104 ( 33 ): 13408 – 13 . doi: 10.1073/pnas.0701553104 . OpenUrl Abstract / FREE Full Text ↵ Binsky , Inbal , Michal Haran , Diana Starlets , Nurit Harpaz , Lev Shvidel , Alain Berrebi , and Idit Shachar . 2006 . “ CD74 Is a Novel Survival Receptor in Chronic Lymphocytic Leukemia .” Blood 108 ( 11 ): 2812 – 2812 . doi: 10.1182/blood.v108.11.2812.2812 . OpenUrl CrossRef ↵ Bloom , B. R. , and B. Bennett . 1966 . “ Mechanism of a Reaction in Vitro Associated with Delayed-Type Hypersensitivity .” Science 153 ( 3731 ): 80 – 82 . doi: 10.1126/science.153.3731.80 . OpenUrl Abstract / FREE Full Text ↵ Bozza , M. , A. R. Satoskar , G. Lin , B. Lu , A. A. Humbles , C. Gerard , and J. R. David . 1999 . “ Targeted Disruption of Migration Inhibitory Factor Gene Reveals Its Critical Role in Sepsis .” The Journal of Experimental Medicine 189 ( 2 ): 341 – 46 . doi: 10.1084/jem.189.2.341 . OpenUrl Abstract / FREE Full Text ↵ Brennan-Bourdon , Lorena Michele , Ulises De la Cruz-Mosso , Zyanya Reyes-Castillo , Gloria Esther Martínez-Bonilla , María Guadalupe Ramírez-Dueñas , María Cristina Islas-Carbajal , Ana Rosa Rincón-Sánchez , Mario Salazar-Páramo , and José Francisco Muñoz-Valle . 2015 . “ MIF and TNFα Serum Levels in Rheumatoid Arthritis Patients Treated with Disease-Modifying Antirheumatic Drugs: A Cross-Sectional Study .” Immunopharmacology and Immunotoxicology 37 ( 2 ): 207 – 13 . doi: 10.3109/08923973.2015.1017645 . OpenUrl CrossRef PubMed ↵ Brocks , Tania , Oleg Fedorchenko , Nicola Schliermann , Astrid Stein , Ute M. Moll , Seth Seegobin , Manfred Dewor , et al. 2017 . “ Macrophage Migration Inhibitory Factor Protects from Nonmelanoma Epidermal Tumors by Regulating the Number of Antigen-Presenting Cells in Skin .” FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology 31 ( 2 ): 526 – 43 . doi: 10.1096/fj.201600860R . OpenUrl CrossRef PubMed ↵ Bucala , Richard , and Seamas C. Donnelly . 2007 . “ Macrophage Migration Inhibitory Factor: A Probable Link between Inflammation and Cancer .” Immunity 26 ( 3 ): 281 – 85 . doi: 10.1016/j.immuni.2007.03.005 . OpenUrl CrossRef PubMed Web of Science ↵ Burger , J. A. , M. Burger , and T. J. Kipps . 1999 . “ Chronic Lymphocytic Leukemia B Cells Express Functional CXCR4 Chemokine Receptors That Mediate Spontaneous Migration beneath Bone Marrow Stromal Cells .” Blood 94 ( 11 ): 3658 – 67 . doi: 10.1182/blood.v94.11.3658.423k11_3658_3667 . OpenUrl Abstract / FREE Full Text ↵ Burger , Jan A. , and John G. Gribben . 2014 . “ The Microenvironment in Chronic Lymphocytic Leukemia (CLL) and Other B Cell Malignancies: Insight into Disease Biology and New Targeted Therapies .” Seminars in Cancer Biology 24 ( February ): 71 – 81 . doi: 10.1016/j.semcancer.2013.08.011 . OpenUrl CrossRef PubMed ↵ Calandra , T. , J. Bernhagen , C. N. Metz , L. A. Spiegel , M. Bacher , T. Donnelly , A. Cerami , and R. Bucala . 1995 . “ MIF as a Glucocorticoid-Induced Modulator of Cytokine Production .” Nature 377 ( 6544 ): 68 – 71 . doi: 10.1038/377068a0 . OpenUrl CrossRef PubMed Web of Science ↵ Calandra , T. , J. Bernhagen , R. A. Mitchell , and R. Bucala . 1994 . “ The Macrophage Is an Important and Previously Unrecognized Source of Macrophage Migration Inhibitory Factor .” The Journal of Experimental Medicine 179 ( 6 ): 1895 – 1902 . doi: 10.1084/jem.179.6.1895 . OpenUrl Abstract / FREE Full Text ↵ Calandra , Thierry , and Thierry Roger . 2003 . “ Macrophage Migration Inhibitory Factor: A Regulator of Innate Immunity .” Nature Reviews. Immunology 3 ( 10 ): 791 – 800 . doi: 10.1038/nri1200 . OpenUrl CrossRef PubMed Web of Science ↵ Cao , W-G , M. Morin , C. Metz , R. Maheux , and A. Akoum . 2005 . “ Stimulation of Macrophage Migration Inhibitory Factor Expression in Endometrial Stromal Cells by Interleukin 1, Beta Involving the Nuclear Transcription Factor NFkappaB .” Biology of Reproduction 73 ( 3 ): 565 – 70 . doi: 10.1095/biolreprod.104.038331 . OpenUrl CrossRef PubMed Web of Science ↵ Chen , Deng , Chunlong Zhao , Jianqiu Zhang , Catharina W. J. Knol , Angelina Osipyan , Nad’a Majerníková , Tingting Chen , et al. 2024 . “ Small Molecule MIF Modulation Enhances Ferroptosis by Impairing DNA Repair Mechanisms .” Advancement of Science , June , e2403963 . doi: 10.1002/advs.202403963 . OpenUrl CrossRef ↵ Chen , H. , M. Centola , S. F. Altschul , and H. Metzger . 1998 . “ Characterization of Gene Expression in Resting and Activated Mast Cells .” The Journal of Experimental Medicine 188 ( 9 ): 1657 – 68 . doi: 10.1084/jem.188.9.1657 . OpenUrl Abstract / FREE Full Text ↵ Clausen , B. E. , C. Burkhardt , W. Reith , R. Renkawitz , and I. Förster . 1999 . Transgenic Research 8 ( 4 ): 265 – 77 . doi: 10.1023/a:1008942828960 . OpenUrl CrossRef PubMed Web of Science ↵ Collard , James P. , Mary K. McKenna , Sunil K. Noothi , Sara S. Alhakeem , Jacqueline R. Rivas , Vivek M. Rangnekar , Natarajan Muthusamy , and Subbarao Bondada . 2022 . “ Role of the Splenic Microenvironment in Chronic Lymphocytic Leukemia Development in Eµ-TCL1 Transgenic Mice .” Leukemia & Lymphoma 63 ( 8 ): 1810 – 22 . doi: 10.1080/10428194.2022.2045596 . OpenUrl CrossRef PubMed ↵ Daryadel , Arezoo , Remo Filippo Grifone , Hans-Uwe Simon , and Shida Yousefi . 2006 . “ Apoptotic Neutrophils Release Macrophage Migration Inhibitory Factor upon Stimulation with Tumor Necrosis Factor-Alpha .” The Journal of Biological Chemistry 281 ( 37 ): 27653 – 61 . doi: 10.1074/jbc.M604051200 . OpenUrl Abstract / FREE Full Text ↵ David , J. R. 1966 . “ Delayed Hypersensitivity in Vitro: Its Mediation by Cell-Free Substances Formed by Lymphoid Cell-Antigen Interaction .” Proceedings of the National Academy of Sciences of the United States of America 56 ( 1 ): 72 – 77 . doi: 10.1073/pnas.56.1.72 . OpenUrl FREE Full Text ↵ Fedorchenko , Oleg , Marius Stiefelhagen , Abdul A. Peer-Zada , Romy Barthel , Petra Mayer , Laura Eckei , Alexandra Breuer , et al. 2013 . “ CD44 Regulates the Apoptotic Response and Promotes Disease Development in Chronic Lymphocytic Leukemia .” Blood 121 ( 20 ): 4126 – 36 . doi: 10.1182/blood-2012-11-466250 . OpenUrl Abstract / FREE Full Text ↵ Fingerle-Rowson , G. , O. Petrenko , C. N. Metz , T. G. Forsthuber , R. Mitchell , R. Huss , U. Moll , W. Müller , and R. Bucala . 2003 . “ The P53-Dependent Effects of Macrophage Migration Inhibitory Factor Revealed by Gene Targeting .” Proceedings of the National Academy of Sciences of the United States of America 100 ( 16 ): 9354 – 59 . doi: 10.1073/pnas.1533295100 . OpenUrl Abstract / FREE Full Text ↵ Flieger , Oliver , André Engling , Richard Bucala , Hongqi Lue , Walter Nickel , and Jürgen Bernhagen . 2003 . “ Regulated Secretion of Macrophage Migration Inhibitory Factor Is Mediated by a Non-Classical Pathway Involving an ABC Transporter .” FEBS Letters 551 ( 1–3 ): 78 – 86 . doi: 10.1016/s0014-5793(03)00900-1 . OpenUrl CrossRef PubMed Web of Science ↵ Gore , Yael , Diana Starlets , Nitsan Maharshak , Shirly Becker-Herman , Utako Kaneyuki , Lin Leng , Richard Bucala , and Idit Shachar . 2008 . “ Macrophage Migration Inhibitory Factor Induces B Cell Survival by Activation of a CD74-CD44 Receptor Complex .” The Journal of Biological Chemistry 283 ( 5 ): 2784 – 92 . doi: 10.1074/jbc.M703265200 . OpenUrl Abstract / FREE Full Text ↵ Hallek , Michael , Bruce D. Cheson , Daniel Catovsky , Federico Caligaris-Cappio , Guillermo Dighiero , Hartmut Döhner , Peter Hillmen , et al. 2018 . “ IwCLL Guidelines for Diagnosis, Indications for Treatment, Response Assessment, and Supportive Management of CLL .” Blood 131 ( 25 ): 2745 – 60 . doi: 10.1182/blood-2017-09-806398 . OpenUrl Abstract / FREE Full Text ↵ Haran , Michal , Vita Mirkin , Andrei Braester , Nurith Harpaz , Olga Shevetz , Marina Shtreiter , Shulamit Greenberg , et al. 2018 . “ A Phase I-II Clinical Trial of the Anti-CD74 Monoclonal Antibody Milatuzumab in Frail Patients with Refractory Chronic Lymphocytic Leukaemia: A Patient Based Approach .” British Journal of Haematology 182 ( 1 ): 125 – 28 . doi: 10.1111/bjh.14726 . OpenUrl CrossRef PubMed ↵ Howard , Brandon A. , Zhong Zheng , Michael J. Campa , Michael Z. Wang , Anupama Sharma , Eric Haura , James E. Herndon 2nd . , Michael C. Fitzgerald , Gerold Bepler , and Edward F. Patz Jr . 2004 . “ Translating Biomarkers into Clinical Practice: Prognostic Implications of Cyclophilin A and Macrophage Migratory Inhibitory Factor Identified from Protein Expression Profiles in Non-Small Cell Lung Cancer .” Lung Cancer 46 ( 3 ): 313 – 23 . doi: 10.1016/j.lungcan.2004.05.013 . OpenUrl CrossRef PubMed Web of Science ↵ Jestrabek , Hendrik , Viktoria Kohlhas , Michael Hallek , and Phuong-Hien Nguyen . 2024 . “ Impact of Leukemia-Associated Macrophages on the Progression and Therapy Response of Chronic Lymphocytic Leukemia .” Leukemia Research 143 ( June ): 107531 . doi: 10.1016/j.leukres.2024.107531 . OpenUrl CrossRef PubMed ↵ Jung , Haiyoung , Hyun-A Seong , and Hyunjung Ha . 2008 . “ Critical Role of Cysteine Residue 81 of Macrophage Migration Inhibitory Factor (MIF) in MIF-Induced Inhibition of P53 Activity .” The Journal of Biological Chemistry 283 ( 29 ): 20383 – 96 . doi: 10.1074/jbc.M800050200 . OpenUrl Abstract / FREE Full Text ↵ Kleemann , R. , A. Hausser , G. Geiger , R. Mischke , A. Burger-Kentischer , O. Flieger , F. J. Johannes , et al. 2000 . “ Intracellular Action of the Cytokine MIF to Modulate AP-1 Activity and the Cell Cycle through Jab1 .” Nature 408 ( 6809 ): 211 – 16 . doi: 10.1038/35041591 . OpenUrl CrossRef PubMed Web of Science ↵ Koch , Maximilian , Sebastian Reinartz , Julia Saggau , Gero Knittel , Natascha Rosen , Oleg Fedorchenko , Lisa Thelen , et al. 2020 . “ Meta-Analysis Reveals Significant Sex Differences in Chronic Lymphocytic Leukemia Progression in the Eµ-TCL1 Transgenic Mouse Model .” Cancers 12 ( 7 ): 1980 . doi: 10.3390/cancers12071980 . OpenUrl CrossRef PubMed ↵ Koebernick , Heidrun , Leander Grode , John R. David , Wolfgang Rohde , Michael S. Rolph , Hans-Willi Mittrücker , and Stefan H. E. Kaufmann . 2002 . “ Macrophage Migration Inhibitory Factor (MIF) Plays a Pivotal Role in Immunity against Salmonella Typhimurium .” Proceedings of the National Academy of Sciences of the United States of America 99 ( 21 ): 13681 – 86 . doi: 10.1073/pnas.212488699 . OpenUrl Abstract / FREE Full Text ↵ Kohlhas , Viktoria , Michael Hallek , and Phuong-Hien Nguyen . 2020 . “ Constitutive Activation of Lyn Kinase Enhances BCR Responsiveness, but Not the Development of CLL in Eµ-TCL1 Mice .” Blood Advances 4 ( 24 ): 6106 – 16 . doi: 10.1182/bloodadvances.2020002584 . OpenUrl CrossRef PubMed ↵ Leng , Lin , Christine N. Metz , Yan Fang , Jing Xu , Seamas Donnelly , John Baugh , Thomas Delohery , Yibang Chen , Robert A. Mitchell , and Richard Bucala . 2003 . “ MIF Signal Transduction Initiated by Binding to CD74 .” The Journal of Experimental Medicine 197 ( 11 ): 1467 – 76 . doi: 10.1084/jem.20030286 . OpenUrl Abstract / FREE Full Text Lewis , Richard Ian , Alexander Frederik Vom Stein , and Michael J. Hallek . 2024 . “ Targeting the Tumor Microenvironment for Treating Double Refractory Chronic Lymphocytic Leukemia .” Blood , May , blood.2023022861. doi: 10.1182/blood.2023022861 . OpenUrl CrossRef ↵ Li , Jia , Lin Leng , Georgios Pantouris , Ramu Manjula , Marta Piecychna , Laura Abriola , Buqu Hu , et al. 2024 . “ A Small-Molecule Allele-Selective Transcriptional Inhibitor of the MIF Immune Susceptibility Locus .” The Journal of Biological Chemistry 300 ( 7 ): 107443 . doi: 10.1016/j.jbc.2024.107443 . OpenUrl CrossRef PubMed ↵ Li , Jinhong , Ying Tang , Patrick M. K. Tang , Jun Lv , Xiao-Ru Huang , Christine Carlsson-Skwirut , Lydie Da Costa , et al. 2018 . “ Blocking Macrophage Migration Inhibitory Factor Protects against Cisplatin-Induced Acute Kidney Injury in Mice .” Molecular Therapy: The Journal of the American Society of Gene Therapy 26 ( 10 ): 2523 – 32 . doi: 10.1016/j.ymthe.2018.07.014 . OpenUrl CrossRef PubMed ↵ Liao , Yunxi , Chenyang Wu , Yang Li , Jinhua Wen , and Dongyu Zhao . 2023 . “ MIF Is a Critical Regulator of Mononuclear Phagocytic Infiltration in Hepatocellular Carcinoma .” IScience 26 ( 8 ): 107273 . doi: 10.1016/j.isci.2023.107273 . OpenUrl CrossRef PubMed ↵ Meyer-Siegler , K. , and P. Hudson . 1996 . “ Enhanced Expression of Macrophage Migration Inhibitory Factor in Prostatic Adenocarcinoma Metastases .” Urology 48 ( 3 ): 448 – 52 . doi: 10.1016/S0090-4295(96)00207-5 . OpenUrl CrossRef PubMed Web of Science Mitchell , Robert A. 2004 . “ Mechanisms and Effectors of MIF-Dependent Promotion of Tumourigenesis .” Cellular Signalling 16 ( 1 ): 13 – 19 . doi: 10.1016/j.cellsig.2003.07.002 . OpenUrl CrossRef PubMed Web of Science ↵ Mittal , Amit K. , Nagendra K. Chaturvedi , Karan J. Rai , Christine E. Gilling-Cutucache , Tara M. Nordgren , Margaret Moragues , Runqing Lu , et al. 2014 . “ Chronic Lymphocytic Leukemia Cells in a Lymph Node Microenvironment Depict Molecular Signature Associated with an Aggressive Disease .” Molecular Medicine (Cambridge, Mass .) 20 ( 1 ): 290 – 301 . doi: 10.2119/molmed.2012.00303 . OpenUrl CrossRef PubMed ↵ Nguyen , Phuong-Hien , Oleg Fedorchenko , Natascha Rosen , Maximilian Koch , Romy Barthel , Tomasz Winarski , Alexandra Florin , F. Thomas Wunderlich , Nina Reinart , and Michael Hallek . 2016 . “ LYN Kinase in the Tumor Microenvironment Is Essential for the Progression of Chronic Lymphocytic Leukemia .” Cancer Cell 30 ( 4 ): 610 – 22 . doi: 10.1016/j.ccell.2016.09.007 . OpenUrl CrossRef PubMed ↵ Pritchard , Jessica E. , Juliette E. Pearce , Inge A. M. Snoeren , Stijn N. R. Fuchs , Katrin Götz , Fabian Peisker , Silke Wagner , et al. 2024 . “ Non-Canonical Hedgehog Signaling Mediates Profibrotic Hematopoiesis-Stroma Crosstalk in Myeloproliferative Neoplasms .” Cell Reports 43 ( 1 ): 113608 . doi: 10.1016/j.celrep.2023.113608 . OpenUrl CrossRef PubMed ↵ Reinart , Nina , Phuong-Hien Nguyen , Jorge Boucas , Natascha Rosen , Hans-Michael Kvasnicka LukasHeukamp , Cornelia Rudolph , et al. 2013 . “ Delayed Development of Chronic Lymphocytic Leukemia in the Absence of Macrophage Migration Inhibitory Factor .” Blood 121 ( 5 ): 812 – 21 . doi: 10.1182/blood-2012-05-431452 . OpenUrl Abstract / FREE Full Text ↵ Rickert , R. C. , J. Roes , and K. Rajewsky . 1997 . “ B Lymphocyte-Specific, Cre-Mediated Mutagenesis in Mice .” Nucleic Acids Research 25 ( 6 ): 1317 – 18 . doi: 10.1093/nar/25.6.1317 . OpenUrl CrossRef PubMed Web of Science ↵ Rossi , A. G. , C. Haslett , N. Hirani , A. P. Greening , I. Rahman , C. N. Metz , R. Bucala , and S. C. Donnelly . 1998 . “ Human Circulating Eosinophils Secrete Macrophage Migration Inhibitory Factor (MIF). Potential Role in Asthma .” The Journal of Clinical Investigation 101 ( 12 ): 2869 – 74 . doi: 10.1172/JCI1524 . OpenUrl CrossRef PubMed Web of Science ↵ Rossmueller , Gregor , Irina Mirkina , Barbara Maurer , Verena Hoeld , Julia Mayer , Michael Thiele , Randolf J. Kerschbaumer , and Alexander Schinagl . 2023 . “ Preclinical Evaluation of ON203, A Novel Bioengineered MAb Targeting Oxidized Macrophage Migration Inhibitory Factor as an Anticancer Therapeutic .” Molecular Cancer Therapeutics 22 ( 5 ): 555 – 69 . doi: 10.1158/1535-7163.MCT-22-0676 . OpenUrl CrossRef PubMed ↵ Shi , Xuerong , Lin Leng , Tian Wang , Wenkui Wang , Xin Du , Ji Li , Courtney McDonald , et al. 2006 . “ CD44 Is the Signaling Component of the Macrophage Migration Inhibitory Factor-CD74 Receptor Complex .” Immunity 25 ( 4 ): 595 – 606 . doi: 10.1016/j.immuni.2006.08.020 . OpenUrl CrossRef PubMed Web of Science ↵ Smith , Candice A. , Daniel J. Tyrell , Upasana A. Kulkarni , Sherri Wood , Lin Leng , Rachel L. Zemans , Richard Bucala , and Daniel R. Goldstein . 2019 . “ Macrophage Migration Inhibitory Factor Enhances Influenza-Associated Mortality in Mice .” JCI Insight 4 ( 13 ). doi: 10.1172/jci.insight.128034 . OpenUrl CrossRef ↵ Spertini , Caroline , Alexandre P. Bénéchet , Flora Birch , Axel Bellotti , Mónica Román-Trufero , Caroline Arber , Holger W. Auner , Robert A. Mitchell , Olivier Spertini , and Tatiana Smirnova . 2024 . “ Macrophage Migration Inhibitory Factor Blockade Reprograms Macrophages and Disrupts Prosurvival Signaling in Acute Myeloid Leukemia .” Cell Death Discovery 10 ( 1 ): 157 . doi: 10.1038/s41420-024-01924-5 . OpenUrl CrossRef PubMed ↵ Talos , F. , P. Mena , G. Fingerle-Rowson , U. Moll , and O. Petrenko . 2005 . “ MIF Loss Impairs Myc-Induced Lymphomagenesis .” Cell Death and Differentiation 12 ( 10 ): 1319 – 28 . doi: 10.1038/sj.cdd.4401653 . OpenUrl CrossRef PubMed ↵ Tanese , Keiji , and Dai Ogata . 2024 . “ The Role of Macrophage Migration Inhibitory Factor Family and CD74 in the Pathogenesis of Melanoma .” Experimental Dermatology 33 ( 6 ): e15122 . doi: 10.1111/exd.15122 . OpenUrl CrossRef PubMed ↵ Taylor , John A. , 3rd . , George A. Kuchel , Poornima Hegde , Olga S. Voznesensky , Kevin Claffey , John Tsimikas , Lin Leng , Richard Bucala , and Carol Pilbeam . 2007 . “ Null Mutation for Macrophage Migration Inhibitory Factor (MIF) Is Associated with Less Aggressive Bladder Cancer in Mice .” BMC Cancer 7 ( July ): 135 . doi: 10.1186/1471-2407-7-135 . OpenUrl CrossRef PubMed ↵ Thavayogarajah , Tharshika , Dzmitry Sinitski , Omar El Bounkari , Laura Torres-Garcia , Hadas Lewinsky , Alexander Harjung , Hong-Ru Chen , et al. 2022 . “ CXCR4 and CD74 Together Enhance Cell Survival in Response to Macrophage Migration-Inhibitory Factor in Chronic Lymphocytic Leukemia .” Experimental Hematology 115 ( November ): 30 – 43 . doi: 10.1016/j.exphem.2022.08.005 . OpenUrl CrossRef PubMed ↵ Thiele , Michael , Seamas C. Donnelly , and Robert A. Mitchell . 2022 . “ OxMIF: A Druggable Isoform of Macrophage Migration Inhibitory Factor in Cancer and Inflammatory Diseases .” Journal for Immunotherapy of Cancer 10 ( 9 ): e005475 . doi: 10.1136/jitc-2022-005475 . OpenUrl Abstract / FREE Full Text ↵ Ullah , Md Ashik , Beatriz Garcillán , Eden Whitlock , William A. Figgett , Simona Infantino , Mahya Eslami , Siling Yang , et al. 2024 . “ An Unappreciated Cell Survival-Independent Role for BAFF Initiating Chronic Lymphocytic Leukemia .” Frontiers in Immunology 15 ( February ): 1345515 . doi: 10.3389/fimmu.2024.1345515 . OpenUrl CrossRef PubMed ↵ Valdez , Caroline Naomi , Gabriela Athziri Sánchez-Zuno , Lais Osmani , Wael Ibrahim , Anjela Galan , Antonietta Bacchiocchi , Ruth Halaban , et al. 2024 . “ Prognostic and Therapeutic Insights into MIF, DDT, and CD74 in Melanoma .” Oncotarget 15 ( July ): 507 – 20 . doi: 10.18632/oncotarget.28615 . OpenUrl CrossRef PubMed Vom Stein , Alexander F. , Michael Hallek , and Phuong-Hien Nguyen . 2023 . “ Role of the Tumor Microenvironment in CLL Pathogenesis .” Seminars in Hematology , December . doi: 10.1053/j.seminhematol.2023.12.004 . OpenUrl CrossRef ↵ Weber , Christian , Sandra Kraemer , Maik Drechsler , Hongqi Lue , Rory R. Koenen , Aphrodite Kapurniotu , Alma Zernecke , and Jürgen Bernhagen . 2008 . “ Structural Determinants of MIF Functions in CXCR2-Mediated Inflammatory and Atherogenic Leukocyte Recruitment .” Proceedings of the National Academy of Sciences of the United States of America 105 ( 42 ): 16278 – 83 . doi: 10.1073/pnas.0804017105 . OpenUrl Abstract / FREE Full Text ↵ Wirtz , Theresa H. , Alena Saal , Irina Bergmann , Petra Fischer , Daniel Heinrichs , Elisa F. Brandt , MariaT. Koenen , et al. 2021 . “ Macrophage Migration Inhibitory Factor Exerts Pro-Proliferative and Anti-Apoptotic Effects via CD74 in Murine Hepatocellular Carcinoma .” British Journal of Pharmacology 178 ( 22 ): 4452 – 67 . doi: 10.1111/bph.15622 . OpenUrl CrossRef PubMed ↵ Xiao , Zhangping , Shanshan Song , Deng Chen , Ronald van Merkerk , Petra E. van der Wouden , Robbert H. Cool , Wim J. Quax , Gerrit J. Poelarends , Barbro N. Melgert , and Frank J. Dekker . 2021 . “ Proteolysis Targeting Chimera (PROTAC) for Macrophage Migration Inhibitory Factor (MIF) Has Anti-Proliferative Activity in Lung Cancer Cells .” Angewandte Chemie (International Ed. in English) 60 ( 32 ): 17514 – 21 . doi: 10.1002/anie.202101864 . OpenUrl CrossRef ↵ Yaddanapudi , Kavitha , Beatriz E. Rendon , Gwyneth Lamont , Eun Jung Kim , Numan Al Rayyan , Jamaal Richie , Sabrin Albeituni , Sabine Waigel , Ashley Wise , and Robert A. Mitchell . 2016 . “ MIF Is Necessary for Late-Stage Melanoma Patient MDSC Immune Suppression and Differentiation .” Cancer Immunology Research 4 ( 2 ): 101 – 12 . doi: 10.1158/2326-6066.CIR-15-0070-T . OpenUrl Abstract / FREE Full Text View the discussion thread. Back to top Previous Next Posted February 27, 2025. Download PDF Supplementary Material Email Thank you for your interest in spreading the word about bioRxiv. NOTE: Your email address is requested solely to identify you as the sender of this article. Your Email * Your Name * Send To * Enter multiple addresses on separate lines or separate them with commas. You are going to email the following Systemic MIF facilitates chronic lymphocytic leukemia development independent of its cellular source Message Subject (Your Name) has forwarded a page to you from bioRxiv Message Body (Your Name) thought you would like to see this page from the bioRxiv website. Your Personal Message CAPTCHA This question is for testing whether or not you are a human visitor and to prevent automated spam submissions. Share Systemic MIF facilitates chronic lymphocytic leukemia development independent of its cellular source Viktoria Kohlhas , Nina Reinart , Natascha Rosen , Sebastian Reinartz , Phuong-Hien Nguyen , Michael Hallek bioRxiv 2025.02.22.639632; doi: https://doi.org/10.1101/2025.02.22.639632 Share This Article: Copy Citation Tools Systemic MIF facilitates chronic lymphocytic leukemia development independent of its cellular source Viktoria Kohlhas , Nina Reinart , Natascha Rosen , Sebastian Reinartz , Phuong-Hien Nguyen , Michael Hallek bioRxiv 2025.02.22.639632; doi: https://doi.org/10.1101/2025.02.22.639632 Citation Manager Formats BibTeX Bookends EasyBib EndNote (tagged) EndNote 8 (xml) Medlars Mendeley Papers RefWorks Tagged Ref Manager RIS Zotero Tweet Widget Facebook Like Google Plus One Subject Area Cancer Biology Subject Areas All Articles Animal Behavior and Cognition (7622) Biochemistry (17648) Bioengineering (13870) Bioinformatics (41880) Biophysics (21423) Cancer Biology (18553) Cell Biology (25458) Clinical Trials (138) Developmental Biology (13364) Ecology (19866) Epidemiology (2067) Evolutionary Biology (24290) Genetics (15589) Genomics (22475) Immunology (17711) Microbiology (40327) Molecular Biology (17145) Neuroscience (88472) Paleontology (666) Pathology (2826) Pharmacology and Toxicology (4815) Physiology (7635) Plant Biology (15114) Scientific Communication and Education (2044) Synthetic Biology (4286) Systems Biology (9815) Zoology (2268)