Synergistic immunostimulation between Leishmania donovani antigen and Carissa edulis in BALB/c mice with visceral leishmaniasis

Synergistic immunostimulation between Leishmania donovani antigen and Carissa edulis in BALB/c mice with visceral leishmaniasis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (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],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Synergistic immunostimulation between Leishmania donovani antigen and Carissa edulis in BALB/c mice with visceral leishmaniasis Judith Njeri, Joshua M Mutiso, Rebeccah M Ayako, Michael M Gicheru This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7692689/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 5 You are reading this latest preprint version Abstract Visceral leishmaniasis (VL) is a significant health issue because of limited administration of chemotherapy treatment, being too toxic and even emerging forms of resistance that necessitates to develop new forms of immunotherapeutic treatment. The research compared the adjuvant (vaccination) capacity of Carissa edulis extract combined with soluble Leishmania donovani antigen (SLA) in the BALB/c mice. Eighty BALB/c mice received SLA, C. edulis, combination, or PBS, then challenged with L. donovani; parasite, cytokine, antibodies measured. The highest protection in the mice vaccinated with SLA + C. edulis (4.9%-6.0) was observed, parasite burden which was lower as compared to the SLA + C. edulis (4.9) and also C. edulis (4.9). The biggest cytokine profile accused the best cytokines profile, with significantly higher levels of IFN-γ (217.4 pgmL (p = 0.0110)) as well as postponed levels of IL-10 (35-40 pgmL). The combination group showed robust activation of humoral response given that IgG2a performed as high as (3 mg/mL (p = 0.0245) markedly higher as compared to either treatment, whereas IgG1 increases were smaller and SLA-dependent. It was further ascertained that the level of parasite burden is positively correlated with IL-10 (r = 0.97, p = 0.0061) and IgG1 (r = 0.92, p = 0.0278), but negatively with IgG2a, which supports the protective nature of Th1-related immunities. The results have shown that the extract of C. edulis is synergistically antigenic stimulating the Th1-biased response with increased IFN-γ and IgG2a, and decreased IL-10, as well as enhanced the parasite clearance effect. Immunomodulation visceral leishmaniasis Carissa edulis IgG Cytokines Full Text Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 29 Sep, 2025 Reviewers invited by journal 29 Sep, 2025 Editor invited by journal 25 Sep, 2025 Editor assigned by journal 24 Sep, 2025 First submitted to journal 23 Sep, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7692689","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":522392965,"identity":"91d5bf45-04e5-4162-9162-915181352f7c","order_by":0,"name":"Judith Njeri","email":"","orcid":"","institution":"Kenyatta University","correspondingAuthor":false,"prefix":"","firstName":"Judith","middleName":"","lastName":"Njeri","suffix":""},{"id":522392966,"identity":"a67689b3-a58f-40ce-ba14-1f0b1c40e1bd","order_by":1,"name":"Joshua M Mutiso","email":"","orcid":"","institution":"Kenyatta 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