Delay of early B-lymphocyte development by gamma 2b immunoglobulin transgene: effect on differentiation-specific molecules.
Mice transgenic for gamma 2b Ig heavy chain were examined for alterations in B-cell differentiation and endogenous Ig gene rearrangement and expression. Fresh bone marrow from these mice was markedly reduced in BP-1+ cells and there were small reductions in B220+ and sIg+ cells. A-MuLV (Abelson murine leukemia virus) transformants from these bone marrow cells showed little alteration in Ig gene rearrangement and expression when compared to controls, however. Isolation of the B-lymphoid compartment from these mice in vitro using LBMC (lymphoid bone marrow cultures) enabled more detailed characterization of the effects of the transgene. LBMC derived from gamma 2b transgenic mice had similar growth kinetics, but a 4-5-week delay in the expression of endogenous mu Ig in comparison to control cultures. Nucleic acids derived from these early cultures prior to endogenous mu Ig expression showed reduced Ig JH rearrangements, some sterile mu transcription, low levels of BP-1 expression, and virtually undetectable TdT (terminal deoxynucleotidyl transferase) expression. Thus, this gamma 2b transgene appears able to affect early B-lymphocyte development.
Denis
K A
KA
Howard Hughes Medical Institute, UCLA 90024.
Provost
S
S
Witte
O N
ON
Brinster
R L
RL
Storb
U
U
D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D001853:Bone Marrow / Q000276:immunology; D001854:Bone Marrow Cells; D002454:Cell Differentiation; D046508:Culture Techniques; D015870:Gene Expression; D015334:Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor; D005803:Genes, Immunoglobulin; D007142:Immunoglobulin gamma-Chains / Q000235:genetics*; D007148:Immunoglobulin mu-Chains / Q000235:genetics; D051379:Mice; D008822:Mice, Transgenic; D014158:Transcription, Genetic
D007142:Immunoglobulin gamma-Chains; D007148:Immunoglobulin mu-Chains