Expression of CD7 on normal human myeloid progenitors.
Existence of biphenotypic leukemias co-expressing CD7 and CD34 has prompted the question of whether a similar population of cells is present in normal human bone marrow. As CD7 is considered to be a T cell-restricted Ag, the co-expression of CD7 with the "human stem cell Ag" CD34 may identify a bipotent stage within hemopoietic differentiation. Cells with this phenotype have previously been isolated from human thymus. In this report we provide evidence that human marrow mononuclear cells also contain a minor subpopulation of cells co-expressing CD7 and CD34. The CD7+/CD34+ cells were found to contain committed myeloid progenitors assayed both as CFU in semi-solid media and by their ability to produce granulocytes in long term marrow cultures. Expression of CD7 on myeloid committed progenitors was further confirmed in a C-mediated cytotoxic assay. We conclude that CD7 expression is not restricted to T cells but is also expressed during early stages of myeloid differentiation.
Chabannon
C
C
Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, WA 98104.
Wood
P
P
Torok-Storb
B
B
D015703:Antigens, CD / Q000378:metabolism*; D018952:Antigens, CD34; D019011:Antigens, CD7; D000945:Antigens, Differentiation, T-Lymphocyte / Q000378:metabolism*; D001854:Bone Marrow Cells; D002469:Cell Separation; D005434:Flow Cytometry; D006098:Granulocytes / Q000166:cytology; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000276:immunology*; D006801:Humans
D015703:Antigens, CD; D018952:Antigens, CD34; D019011:Antigens, CD7; D000945:Antigens, Differentiation, T-Lymphocyte