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Dominant role of the α-chain in rejection of tumor cells bearing a specific alloantigen in TCRα transgenic mice and in in vitro experiments.

ABSTRACT: Both TCRα and TCRβ types of T-cell receptors contribute to antigen recognition. However, some TCRs have chain centricity, which means that either the α-chain or the β-chain dictates the peptide-MHC complex specificity. Most earlier reports investigated the role of well-studied β-chains in antigen recognition by TCRαβ. In a previous study, we identified TCRs specific to the H-2K^b molecule. In the present work, we generated transgenic mice carrying the α-chain of this TCR. We found that these transgenic mice rejected EL-4 tumor cells bearing alloantigen H-2K^b more effectively than wild-type mice and similarly to mice with established specific memory T cells. Moreover, we found that T cells transduced with this TCRα can inhibit EL-4 cell growth in vitro and in vivo. We also found that transgenic mice recruit fewer CD8 T cells into the peritoneal cavity at the peak of the immune response and had a significantly higher number of central memory CD8 T cells in the spleen of intact transgenic mice compared to intact wild-type control. These results indicate the ability of a single transgenic α-chain of the H-2K^b-specific TCR to determine specific recognition of the H-2K^b molecule by a repertoire of T lymphocytes and to rapidly reject H-2K^b-bearing lymphoma cells.

SUBMITTER: Zamkova M

PROVIDER: S-EPMC6690675 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Dominant role of the α-chain in rejection of tumor cells bearing a specific alloantigen in TCRα transgenic mice and in <i>in vitro</i> experiments.

Zamkova Maria M Kalinina Anastasiya A Silaeva Yuliya Y Persiyantseva Nadezhda N Bruter Alexandra A Deikin Alexey A Khromykh Ludmila L Kazansky Dmitry D

Oncotarget 20190806 47

Both TCRα and TCRβ types of T-cell receptors contribute to antigen recognition. However, some TCRs have chain centricity, which means that either the α-chain or the β-chain dictates the peptide-MHC complex specificity. Most earlier reports investigated the role of well-studied β-chains in antigen recognition by TCRαβ. In a previous study, we identified TCRs specific to the H-2K<sup>b</sup> molecule. In the present work, we generated transgenic mice carrying the α-chain of this TCR. We found that ...[more]

PMID: 31448049

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Dataset Information

Dominant role of the α-chain in rejection of tumor cells bearing a specific alloantigen in TCRα transgenic mice and in in vitro experiments.

Publications

Dominant role of the α-chain in rejection of tumor cells bearing a specific alloantigen in TCRα transgenic mice and in <i>in vitro</i> experiments.

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