⚙
AI-generated deep summary
by claude@2026-07, 2026-07-03
· read from full text
ⓘ
The paper investigated how aging affects the immune cell surface glycocalyx, focusing on α2,6-linked sialic acid levels on T cells. Using T cells from older versus younger animals and a T cell-specific St6gal1 knockout mouse model to deplete α2,6-linked sialic acids, the authors found that α2,6-linked sialic acid is downregulated with age and is associated with accumulation of effector T cells and premature T cell exhaustion. St6gal1-deficient mice showed expanded naïve T cells and impaired control of acute Listeria infection and chronic tumor growth, with partial restoration of tumor control by PD-1 pathway blockade. The study’s limitation is that it uses immune cells as a model system and does not directly measure glycocalyx remodeling in human disease contexts. This paper does not explicitly discuss endometriosis or adenomyosis; it was included in the corpus via a keyword match in the upstream search index.
Abstract
Cell surface glycans, termed the glycocalyx, are essential regulators of cellular signaling and thus cellular development and functions, but how aging impacts the glycocalyx remains poorly understood. Here, using immune cells as a model system for studying the relationship between aging and glycocalyx remodeling, we show that α2,6-linked sialic acid – a terminal glycan epitope typically associated with inhibitory signaling – becomes downregulated in T cells from older animals. This downregulation is tightly correlated with age-associated accumulation of effector T cells, which are decorated with little to no α2,6-linked sialic acids. T cell aging renders older individuals more vulnerable to infections and cancers. To understand the role of α2,6-linked sialic acids in T cell physiology, we generated a mouse model with T cell-specific deletion of the sialyltransferase gene St6gal1 . The chronic depletion of α2,6-linked sialic acids led to naïve T (T N ) cells expansion in the periphery and premature T cell exhaustion. As a result, these mice were less able to control acute Listeria infection and chronic tumor growth. Blockade of the PD-1 pathway can partially restore the ability of St6gal1 -deficient T cells to control tumor growth. Together, these data suggest that α2,6-linked sialic acids are critical for maintaining long-term T cell responsiveness, and the loss of α2,6-linked sialic acids may directly contribute to age-related T cell exhaustion.
Full text
1,553 characters
· extracted from
oa-doi-fallback
· click to expand
Abstract
Cell surface glycans, termed the glycocalyx, are essential regulators of cellular signaling and thus cellular development and functions, but how aging impacts the glycocalyx remains poorly understood. Here, using immune cells as a model system for studying the relationship between aging and glycocalyx remodeling, we show that α2,6-linked sialic acid – a terminal glycan epitope typically associated with inhibitory signaling – becomes downregulated in T cells from older animals. This downregulation is tightly correlated with age-associated accumulation of effector T cells, which are decorated with little to no α2,6-linked sialic acids. T cell aging renders older individuals more vulnerable to infections and cancers. To understand the role of α2,6-linked sialic acids in T cell physiology, we generated a mouse model with T cell-specific deletion of the sialyltransferase gene St6gal1. The chronic depletion of α2,6-linked sialic acids led to naïve T (TN) cells expansion in the periphery and premature T cell exhaustion. As a result, these mice were less able to control acute Listeria infection and chronic tumor growth. Blockade of the PD-1 pathway can partially restore the ability of St6gal1-deficient T cells to control tumor growth. Together, these data suggest that α2,6-linked sialic acids are critical for maintaining long-term T cell responsiveness, and the loss of α2,6-linked sialic acids may directly contribute to age-related T cell exhaustion.
Competing Interest Statement
The authors have declared no competing interest.
Text is read by the "Ask this paper" AI Q&A widget below.
Extraction quality varies by source — PMC NXML preserves structure
cleanly, OA-HTML may include some navigation residue, and OA-PDF can
have broken hyphenation. The publisher copy
(via DOI)
is the canonical version.