Table IV.

Survival advantage of IgG1+ cells over IgM+ competitor B cells

IgG1+/IgM+ ratio
BMSpleen
GenotypeNo.ImmatureMature/
 recirculatingT1T2/T3All
 transitionalMature
AA4.1+
 B220+AA4.1
 B220+AA4.1+CD23
 CD19+AA4.1+CD23+
 CD19+AA4.1+
 CD19+AA4.1
 CD19+
IgHγ1μ/+ IgαΔc/+n = 50.06 ± 0.010.16 ± 0.020.058 ± 0.0120.106 ± 0.0070.08 ± 0.010.16 ± 0.02
IgHγ1μ/+ IgαΔc1/Δc1n = 50.83 ± 0.222.24 ± 0.71NDND2.09 ± 0.292.68 ± 0.3
  • In heterozygous IgHγ1μ/+ IgαΔc+/+ and IgHγ1μ/+ IgαΔc1/Δc1 mice, the IgG1+/IgM+ B cell ratio increases with the maturational status. Note the strong increase of the fraction of IgG1+ B cell presence within the mature compartment. BM and splenic cells were surface stained for IgG1/IgM, AA4.1, CD23, and a B cell–specific marker (B220 or CD19) and analyzed by flow cytometry.