Annotation of Bat IGH/L/K Loci and Analysis of the Characteristics of Bat BCR-CDR3 Repertoires

Bats are hosts to a variety of zoonotic viruses because they carry the viruses and show no clinical signs of infection, and little is known about the mechanisms and effects of the B-cell adaptive immune response in bats. In this study, Antrozous pallidus and Rhinolophus ferrumequinum light chains were annotated at the chromosome level for the first time: the IGH locus of the Antrozous pallidus was structurally similar and conserved to that of annotated bats, with no complete IGK locus localised, and Rhinolophus ferrumequinum had a complete IGK locus (17 functional IGKVs); the IGL locus were all conserved and differentiated. BCR CDR3 library construction by 5'RACE and HTS analyses revealed that the gene usage and diversity of bats from different families show some tissue specificity, and are both homogeneous and different from humans and mice. This study will provide new ideas, tools and protocols for analysing the differences in B-cell adaptive immune responses between bats and other mammals.