Fig. 2.

Germline transcription at the Jκ cluster is biallelic. Flow cytometric analysis of marker expression in developing B cells from dκGT-hCD4/Cκ-iYFP compound heterozygous mice. Harvested bone marrow was labeled with antibodies to delineate developing B cell subsets and mark hCD4 expression. The progression of cells from the pro-B to the small resting pre-B cell stages is shown. Small pro-B cells were defined as forward scatter low CD43⁺B220⁺ while small pre-B cells were forward scatter low CD43⁻B220⁺. The intermediate stages represent forward scatter high cells (cycling) with intermediate levels of CD43 progressing from high to low. Data are representative of two independent experiments analyzing three mice each.