kappa/lambda Shifts do not occur during maturation of murine B cells.

We have used highly specific affinity-purified antibodies against mouse kappa- and lambda chains in conjunction with both immunofluorescence analysis on the FACS and enzymatic radioiodination of murine splenocytes and bone marrow cells. Our results indicate that the kappa/lambda ratio of cell surface immunoglobulin is constant during the ontogenetic development of B cells, i.e., a shift in the kappa/lambda ratio does not occur during B cell maturation. Our results suggest that the events controlling kappa and lambda expression on murine B cells are decided very early in ontogeny, before significant antigenic selection.