Front Immunol 2020 14;11:82. Epub 2020 Feb 14.
Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States.
B-1a cells produce "natural" antibodies (Abs) to neutralize pathogens and clear neo self-antigens, but the fundamental selection mechanisms that shape their polyreactive repertoires are poorly understood. Here, we identified a B cell progenitor subset defined by Fc receptor-like 6 (FCRL6) expression, harboring innate-like defense, migration, and differentiation properties conducive for natural Ab generation. Compared to FCRL6 pro B cells, the repressed mitotic, DNA damage repair, and signaling activity of FCRL6 progenitors, yielded V repertoires with biased distal segment accessibility, constrained diversity, and hydrophobic and charged CDR-H3 sequences. Read More