Thymocyte costimulating antigen is CD26 (dipeptidyl-peptidase IV). Costimulation of granulocyte, macrophage, and T lineage cell proliferation via CD26.
The rat thymocyte costimulating protein appears to be involved in the regulation of CD4-/CD8- thymocyte proliferation in vitro. We show that thymocyte costimulating protein is dipeptidyl peptidase IV (E.C.N.3.4.14.5) also known as CD26. Some bone marrow cells as well as CD4-/CD8- and, and to a lesser extent, more differentiated T cells respond by proliferating to a CD26 specific mAb-mediated costimulus that does not influence dipeptidyl dipeptidase IV enzyme activity. This suggests the existence of a CD26-linked regulatory mechanism of proliferation that is operational on granulocyte- and macrophage-lineage cells and throughout T cell development.
Unit of Special Projects, NIAAA, ADAMHA, Rockville, MD 20852.
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Bristol
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Sakaguchi
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Appella
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Doyle
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Takács
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis / Q000502:physiology*; D018819:Dipeptidyl Peptidase 4; D005260:Female; D006098:Granulocytes / Q000276:immunology*; D008213:Lymphocyte Activation; D008262:Macrophage Activation; D051381:Rats; D011915:Rats, Inbred BUF; D011916:Rats, Inbred F344; D013601:T-Lymphocytes / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D018819:Dipeptidyl Peptidase 4