Ordering of Human Bone Marrow B Lymphocyte Precursors by Single-Cell Polymerase Chain Reaction Analyses of the Rearrangement Status of the Immunoglobulin H and L Chain Gene Loci

Abstract
CD19+CD10+ human B lineage bone marrow cells were separated into cycling or resting cells, which differ in their expression of CD34, VpreB, recombination activating gene (RAG-1), and terminal deoxynucleotidyl transferase (TdT). Polymerase chain reaction analyses developed for DHJH and VκJκ, VκJκK(de) and VκK(de) rearrangements with DNA of single cells and a comparison with B lineage cell development in mouse bone marrow, allow to delineate the human B lymphocyte pathway of development as follows: CD34+VpreB+RAG-1+TdT+, DHJH-rearranged, κL germline cycling pre-B I cells → CD34VpreB+μH chain+ (pre-B receptor+) RAG-1TdT, VHDHJH-rearranged, κL germline, cycling pre-B II cells → CD34VpreB, intracytoplasmic μH chain+ (pre-B receptor) RAG-1+/− TdT, VHDHJH-rearranged, mainly κL germline cycling pre-B II cells → CD34VpreB intracytoplasmic μH chain+, RAG-1+TdT, VHDHJH-rearranged, VκJκ-rearranged, IgM, resting pre-B II cells CD34+VpreB, sIgM+, RAG-1+TdT, VHDHJH- and VκJκ-rearranged IgM+ immature B cells → CD34, CD10, sIgM+/sIgD+ mature B cells. This order, for the first time established for human B lineage cells, shows striking similarities with that established for mouse B lineage cells in bone marrow.