A novel stromal cell-dependent B lymphoid stem-like cell line that induces immunoglobulin gene rearrangement.
A stroma-dependent B lymphoid cell line (B31-1) has been established by coculturing sorted stem cells on a novel bone marrow stromal cell line (TBR31-1). B31-1 cells express B220, but do not express other B lymphoid differentiation markers including CD43, heat stable antigen (HSA), or surface immunoglobulin (Ig) M (sIgM), and their Ig heavy chain (IgH) gene loci are germ-line in configuration. The addition of interleukin (IL)-7 or coculture with another stromal cell line, ST2, induces D-J rearrangement of the IgH gene and B lymphocyte differentiation markers. B31-1 cells restore an in vivo repopulation activity to lethally irradiated mice, and the repopulated cells differentiate to HSA+ pre-B cells.Continuous coculture results in two distinct populations, B220(-) c-Kit+ cells and B220(+) c-Kit+ cells; B220(-) c-Kit+ cells are self-renewed and differentiate to B220(+) c-Kit+ cells, while B220(+) c-Kit+ cells produce only B220(+) c-Kit+ cells. Both B220(-) and B220(+) cells similarly express the IgH germ-line transcript (Imu), mRNAs for recombinase (TdT, Rag-1, and Rag-2), and lymphoid-specific transcription factors (Pax-5, EBF, E12/E47, Oct-2, and Ikaros), but the DNA binding activity of Pax-5, EBF, Oct-2, and E2A are low in B220(-) cells and while high in B220(+) cells. These results suggest the existence of at least two active states in the IgH locus before the induction of IgH gene rearrangement during B lymphopoietic development.
Department of Cell Biology, Institute of Development, Aging and Cancer, Tohoku University, Aoba-ku, Sendai, 980-8575, Japan.
K
K
Matsuda
M
M
Koguma
R
R
Okuyama
T
T
Nakazawa
Y
Y
Matsuzaki
H
H
Nakauchi
N
N
Yanai
T
T
Terasaki
M
M
Obinata
D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology* / Q000276:immunology*; D002460:Cell Line; D018920:Coculture Techniques; D015322:Gene Rearrangement, B-Lymphocyte; D005803:Genes, Immunoglobulin; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D017154:Stromal Cells / Q000166:cytology*