Research advances in immune repertoire and high-throughput sequencing in primary biliary cholangitis

Primary biliary cholangitis (PBC) is an autoimmune liver disease with unclear pathogenesis.The amino acid composition and sequence in the complementarity-determining region 3 of T cell receptor (TCR) and B cell receptor (BCR) are highly diverse, which forms a large antigen recognition receptor repertoire, i.e., immune repertoire.In recent years, second-generation sequencing techniques combined with multiplex PCR or amplicon rescue multiplex PCR have been used to study the features of immune repertoire in PBC patients, and it has been found that PBC patients have clonal expansion of specific CD4~+T lymphocytes, clonal diversity of B lymphocytes, somatic hypermutation, and reduction in class switch, as well as increase in clonal diversity after treatment with ursodeoxycholic acid.These findings need to be confirmed by large-scale in vivo and in vitro studies and different immune repertoire research strategies.