Variable expression of Qa-m7, Qa-m8, and Qa-m9 antigenic determinants on primitive hemopoietic precursor cells.
Using monoclonal antibodies, we have analysed the distribution of three recently described Qa antigenic determinants (Qa-m7, Qa-m8 and Qa-m9) on murine clonable hemopoietic progenitor cells and spleen colony-forming units (CFU-S). Cytotoxicity experiments showed that Qa-m7 was expressed on almost all the progenitor cells (colony-forming cells, CFC) of megakaryocytes (MEG-CFC), erythroid cells (E-CFC), B lymphocytes (BL-CFC), and mixed colonies (MIX-CFC) as well as day 13 CFU-S, and a major proportion of granulocyte-macrophage colony-forming cells (GM-CFC) and day 8 CFU-S. Experiments using four sources of granulocyte-macrophage colony-stimulating activity suggested differential expression of Qa-m7 on subpopulations of GM-CFC, those preferentially forming macrophage colonies having lowest Qa-m7 antigen density. Immune rosetting techniques demonstrated the selective expression of Qa-m8 on approximately 50% of MEG-CFC, MIX-CFC and day 13 CFU-S, a pattern similar to that of Qa-m2. In contrast, Qa-m9 was not detected on any of the primitive hemopoietic precursors assayed. The results demonstrate the complexity of the Qa antigenic system, and suggest a possible role for these antigens in hemopoietic differentiation.
Harris
R A
RA
Sandrin
M S
MS
Sutton
V R
VR
Hogarth
P M
PM
McKenzie
I F
IF
Penington
D G
DG
D000818:Animals; D000954:Antigens, Surface / Q000276:immunology*; D001854:Bone Marrow Cells; D003602:Cytotoxicity, Immunologic; D000939:Epitopes / Q000276:immunology*; D006412:Hematopoietic Stem Cells / Q000276:immunology*; D015395:Histocompatibility Antigens Class I; D051379:Mice; D008810:Mice, Inbred C57BL; D012397:Rosette Formation
D000954:Antigens, Surface; D000939:Epitopes; D015395:Histocompatibility Antigens Class I; C032907:Q surface antigens