Targeted gene disruption reveals a role for natural secretory IgM in the maturation of the primary immune response

• DOI: 10.1073/pnas.95.17.10089
• Publication Date: 2002-07-26T14:32:33Z
• Authors: Michael R. Ehrens...; Theresa L. O’Keefe; Sarah L. Davies; Michael S. Neuberger
• Keywords: Immunoglobulin M; B-1 cell

Accelerated development of the secondary immune response may be attributable in part to rapid delivery antigen lymphoid follicles by circulating antibody elicited on primary immunization. Here we provide evidence indicating that nonspecific IgM present naive mice (natural antibody) plays a role acceleration response. Targeted deletion Ig μ s polyadenylation site use Cre recombinase allowed creation that, although harboring normal number B cells expressing surface IgM, completely lacked serum while retaining other isotypes. These retained broadly lymphocyte distribution (although containing somewhat expanded peritoneal B1a subset) but exhibited substantial delays mounting affinity-matured IgG responses T cell-dependent antigens. The cell-independent response, however, was augmented. data indicate before challenge (as well, possibly, as immediately after immunization) accelerates maturation presumably complexing with and facilitating activation and/or trapping.