Intrathymic changes in murine CD3, CD5 and CD8 expression after in vivo administration of anti-CD4.
Intrathymic development of murine cortical and medullary thymocyte subpopulations was examined after in vivo administration of anti-CD4 mAb. Four days after mice received 1 mg anti-CD4, expression of CD4 was reduced to about 25% the levels of controls. On cortical CD8+/PNAhigh thymocytes, CD5 and CD8 expression both decreased, but not in parallel, whereas CD3 expression increased almost 2-fold. Partial shifts in CD3 expression were seen 3 and 6 h after injection, but modulation of CD4 preceded the increase in CD3 expression. On medullary CD8-/PNAlow thymocytes, both CD3 and CD5 were down regulated. On nontargeted CD8+/PNAlow medullary thymocytes, expression of these molecules was decreased less than 20%, but the decrease in CD8 expression was primarily due to the appearance of a CD8low subpopulation. The results indicate that anti-CD4 mAb differentially affects the intrathymic development of T cell populations.
Ermak
T H
TH
Cell Biology and Aging Section, VA Medical Center, San Francisco, California.
Steger
H J
HJ
Pappo
J
J
D000818:Animals; D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation / Q000378:metabolism*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000378:metabolism*; D017252:CD3 Complex; D015704:CD4 Antigens / Q000378:metabolism / Q000502:physiology*; D018956:CD5 Antigens; D016827:CD8 Antigens; D005260:Female; D005434:Flow Cytometry; D051379:Mice; D008807:Mice, Inbred BALB C; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism*; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation; D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D015704:CD4 Antigens; D018956:CD5 Antigens; D016827:CD8 Antigens; D011948:Receptors, Antigen, T-Cell