Comprehensive profiling of TCRβ repertoire in a non-model species (the bank vole) using high-throughput sequencing

Abstract

In recent years, immune repertoire profiling with high-throughput sequencing (HTS) has advanced our understanding of adaptive immunity. However, fast progress in the field applied mostly to human and mouse research, with only few studies devoted to other model vertebrates. We present the first in-depth characterization of the TCR{beta} repertoire in a non-model mammal with limited genomic resources available - the bank vole (Myodes glareolus). We used 5'RACE and Illumina HTS to describe V and J segments and to qualitatively characterize preferential V-J segment usage and CDR3 length distribution. Finally, a molecular protocol integrating unique molecular identifiers was used for quantitative analysis of CDR3 repertoire with stringent error correction. We found 37 V and 11 J genes that were orthologous to mice genes. A conservative, lower bound estimation of the TCR{beta} repertoire was 1.7-2.3x105 clonotypes, and the degree of sharing of the observed repertoire between any two individuals was 3.6% of nucleotide sequences and 14.3% of amino acid sequences. Our work adds a crucial element to the immunogenetic resources available for the bank vole, an important species in ecological and evolutionary research. The workflow that we developed can be applied for immune repertoire sequencing of non-model species, including endangered vertebrates.