(A) The phenotypes of splenic (A) and peritoneal (B) DEX+ λ1+ B cells from pre-immune BALB/c mice were determined by flow cytometry using antibodies specific for splenic (see comment 12, reviewer 2) MZ (B220 + CD21hi CD23-), RF (B220 + CD21 int CD23+), B2 (IgM int CD5- Mac-1-), B1a (IgM hi CD5+ Mac-1+), and B1b (IgM hi CD5- Mac-1-). (C) Graph of total numbers DEX+ λ1+ B cell subsets per mouse (n=5 mice).