Murine B lymphocyte heterogeneity: distribution of complement receptor-bearing and minor lymphocyte-stimulating B lymphocytes among cells with different densities of total surface Ig and IgM.

The distribution of complement receptor-bearing (CR+) and minor lymphocyte-stimulating (Mls)-defined lymphocyte-activating determinants (LAD) among B lymphocytes with different densities of total surface immunoglobulin (sIg) and sIgM was determined. B lymphocytes that bore intermediate densities of sIg and low densities of sIgM had the highest frequency of CR+ cells and were the most active in expressing Mls-defined LAD. The distribution of these and other surface markers on B-lymphocyte subpopulations is discussed.