Surface immunoglobulin phenotype of murine spleen cells which form B cell colonies in agar.

Separation of IgD-bearing B lymphocytes from the spleens of 3-week-old or adult mice has been achieved using cellular affinity columns and an anti-delta allotype serum. The results demonstrate that the majority of cells capable of forming B lymphocyte colonies in agar are delta-positive although they lose detectable IgD upon stimulation. It is proposed that these cells are the descendants of IgD-negative cells found in the fetal liver and neonatal spleen.