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TCRβ rearrangements without a D segment are common, abundant, and public.

ABSTRACT: T cells play an important role in adaptive immunity. An enormous clonal diversity of T cells with a different specificity, encoded by the T cell receptor (TCR), protect the body against infection. Most TCRβ chains are generated from a V, D, and J segment during recombination in the thymus. Although complete absence of the D segment is not easily detectable from sequencing data, we find convincing evidence for a substantial proportion of TCRβ rearrangements lacking a D segment. Additionally, sequences without a D segment are more likely to be abundant within individuals and/or shared between individuals. Our analysis indicates that such sequences are preferentially generated during fetal development and persist within the elderly. Summarizing, TCRβ rearrangements without a D segment are not uncommon, and tend to allow for TCRβ chains with a high abundance in the naive repertoire.

SUBMITTER: de Greef PC

PROVIDER: S-EPMC8488670 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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TCRβ rearrangements without a D segment are common, abundant, and public.

de Greef Peter C PC de Boer Rob J RJ

Proceedings of the National Academy of Sciences of the United States of America 20210901 39

T cells play an important role in adaptive immunity. An enormous clonal diversity of T cells with a different specificity, encoded by the T cell receptor (TCR), protect the body against infection. Most TCRβ chains are generated from a V, D, and J segment during recombination in the thymus. Although complete absence of the D segment is not easily detectable from sequencing data, we find convincing evidence for a substantial proportion of TCRβ rearrangements lacking a D segment. Additionally, sequ ...[more]

PMID: 34551975

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