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Biology subjects

Serwold, T.

Publications and source records attributed to Serwold, T..

2 recordsLinked to original sources

A biomimetic five-module chimeric antigen receptor (5MCAR) designed to target and eliminate antigen-specific T cells

T cells express clonotypic T cell receptors (TCRs) that recognize peptide antigens in the context of class I or II MHC molecules (pMHCI/II). These receptor modules associate with three signaling modules (CD3{gamma}{varepsilon}, {delta}{varepsilon}, and {zeta}{zeta}), and work in concert with a coreceptor module (either CD8 or CD4), to drive T cell activation in response to pMHCI/II. Here we describe a first generation biomimetic 5-module chimeric antigen receptor (5MCAR). We show that: (i) chimeric receptor modules built with the ectodomains of pMHCII assemble with CD3 signaling modules into complexes that redirect cytotoxic T lymphocyte (CTL) specificity and function in response to the clonotypic TCRs of pMHCII-specific CD4+ T cells; and, (ii) surrogate coreceptor modules enhance the function of these complexes. Furthermore, we demonstrate that adoptively transferred 5MCAR-CTLs can mitigate type I diabetes by targeting autoimmune CD4+ T cells in NOD mice. This work provides a framework for the construction of biomimetic 5MCARs that can be used as tools to study the impact of particular antigen-specific T cells in immune responses, and may hold potential for ameliorating diseases mediated by pathogenic T cells.

bioengineering↗

The CD11a and EPCR marker combination simplifies and improves the purification of mouse hematopoietic stem cells

Hematopoietic stem cells (HSCs) are the self-renewing multipotent progenitors to all blood cell types. Identification and isolation of HSCs for study has depended on the expression of combinations of surface markers on HSCs that reliably distinguish it from other cell types. However, the increasing number of markers required to isolate HSCs has made it tedious, expensive, and difficult for newcomers, suggesting the need for a simpler panel of HSC markers. We previously showed that phenotypic HSCs could be separated based on expression of CD11a, and that only the CD11a negative fraction contained true HSCs. Here, we show that CD11a and another HSC marker, EPCR, can be used to effectively identify and purify HSCs. We introduce a new two-color HSC sorting method that can highly enrich for HSCs with efficiencies comparable to the gold standard combination of CD150 and CD48. Our results demonstrate that adding CD11a and EPCR to the HSC biologists toolkit improves the purity of and simplifies isolation of HSCs.\n\nSignificance StatementThe study of hematopoietic stem cells (HSCs) and their purification for transplantation requires a panel of surface markers that can be used to distinguish HSCs from other cell types. The number of markers necessary to identify HSCs continues to grow, making it increasingly difficult to identify HSCs by flow cytometry. In this study, we identified a combination of two surface markers, CD11a and EPCR, to enrich for HSCs in the mouse bone marrow without the need for additional markers. This simplified panel could aid HSC research by reducing the number of markers necessary to identify and isolate HSCs.

immunology↗