Stochastic pairing of Ig heavy and light chains frequently generates B cell antigen receptors that are subject to editing in vivo.
We examined the generation and selection of the B cell antibody repertoire through crossing of mice bearing distinct Ig heavy (H) and light (L) chain rearranged variable region transgenes. Ig gene knock-in and transgenic mice whose H and L chains pair to form a non-autoreactive, functional B cell antigen receptor (BCR) have significantly reduced pre-B cells in the bone marrow as their B cell progenitors rapidly differentiate into surface IgM(+) B cells. The presence of a pre-B cell compartment in these Ig transgenic mice, however, indicates the induction of receptor editing. Here, 18 distinct combinations of H and L chains were generated that we showed could pair in vitro to form BCRs of unknown specificities. Of these, nine induced receptor editing in vivo as evidenced by the presence of pre-B cells and endogenous L chain rearrangements in mice bearing these H and L chain transgenes. These data thus suggest that about half of the emerging antibody repertoire is negatively selected during B lymphopoiesis due to the likely encoding of autoreactive or non-functional BCRs.
Novobrantseva
Tatiana
T
Institute for Genetics, University of Cologne, Weyertal 121, D-50931 Cologne, Germany.
Xu
Shengli
S
Tan
Joy En-Lin
JE
Maruyama
Mitsuo
M
Schwers
Stephan
S
Pelanda
Roberta
R
Lam
Kong-Peng
KP
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology; D001853:Bone Marrow / Q000276:immunology; D001854:Bone Marrow Cells / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology; D007143:Immunoglobulin Heavy Chains / Q000235:genetics / Q000276:immunology*; D007147:Immunoglobulin Light Chains / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008822:Mice, Transgenic; D011947:Receptors, Antigen, B-Cell / Q000276:immunology*
D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D011947:Receptors, Antigen, B-Cell