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

CD19(+)CD10(+) human B lineage bone marrow cells were separated into cycling or resting cells, which differ in their expression of CD34, V(preB), recombination activating gene (RAG-1), and terminal deoxynucleotidyl transferase (TdT). Polymerase chain reaction analyses developed for D(H)J(H) and V(κ)J(κ), V(κ)J(κ)K((de)) and V(κ)K((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(+)V(preB) (+)RAG-1(+)TdT(+), D(H)J(H)-rearranged, κL germline cycling pre-B I cells → CD34(−)V(preB) (+)μH chain(+) (pre-B receptor(+)) RAG-1(−)TdT(−), V(H)D(H)J(H)-rearranged, κL germline, cycling pre-B II cells → CD34(−)V(preB) (−), intracytoplasmic μH chain(+) (pre-B receptor(−)) RAG-1(+/−) TdT(−), V(H)D(H)J(H)-rearranged, mainly κL germline cycling pre-B II cells → CD34(−)V(preB) (−) intracytoplasmic μH chain(+), RAG-1(+)TdT(−), V(H)D(H)J(H)-rearranged, V(κ)J(κ)-rearranged, IgM(−), resting pre-B II cells CD34(+)V(preB) (−), sIgM(+), RAG-1(+)TdT(−), V(H)D(H)J(H)- and V(κ)J(κ)-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.