Immunohistochemical expression of CD68 antigen in human peripheral blood T cells.
CD68 antigen is expressed by tissue macrophages and cells of myeloid/mononuclear lineage. CD68 is recognized by many monoclonal antibodies (mAbs), including KP1, EMB11, Y1/82A, Y2/131, Ki-M6, and Ki-M7. Using the labeled strept-avidin-biotin (LSAB) immunoperoxidase technique, we examined CD68 antigen expression in human peripheral blood T cells. The anti-CD68 mAbs KP1 and EMB11 stained virtually all fresh isolated gamma/delta T cells and CD3-CD56+ natural killer (NK) cells in a granular cytoplasmic pattern. In contrast, fresh isolated CD4+ and CD8+ T lymphocytes showed no detectable reactivity with these two anti-CD68 mAbs. However, in vitro stimulation with T-cell mitogen or recombinant interleukin-2 (rIL-2) induced expression of CD68 antigen in activated CD4+ and CD8+ T lymphocytes. Similarly, the lymphokine-activated killer (LAK) cells generated after long-term (14 to 21 days) culture of peripheral blood mononuclear cells (PBMC) in rIL-2 also showed strong granular cytoplasmic staining by the anti-CD68 antibodies. This study shows that the CD68 antigen is constitutively expressed in NK cells and gamma/delta T cells and that its expression is strongly induced in activated CD4+ and CD8+ T lymphocytes as well as LAK cells.
Hameed
A
A
Department of Pathology, Ohio State University Medical Center, Columbus 43210.
Hruban
R H
RH
Gage
W
W
Pettis
G
G
Fox
W M
WM
D000911:Antibodies, Monoclonal; D015703:Antigens, CD / Q000097:blood*; D015214:Antigens, Differentiation, Myelomonocytic / Q000097:blood*; D005434:Flow Cytometry; D006801:Humans; D007124:Immunoenzyme Techniques; D015979:Killer Cells, Lymphokine-Activated / Q000276:immunology; D007694:Killer Cells, Natural / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D000097382:CD68 Molecule
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; C067980:CD68 antigen, human; D000097382:CD68 Molecule