Inducible T cell antigen 4-1BB. Analysis of expression and function.

K E Pollok; Y J Kim; Z Zhou; J Hurtado; K K Kim; R T Pickard; B S Kwon

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PubMed · 7678621

Inducible T cell antigen 4-1BB. Analysis of expression and function.

K E Pollok·Y J Kim·Z Zhou·J Hurtado·K K Kim·R T Pickard·B S Kwon

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Abstract

4-1BB is an inducible receptor-like protein expressed in both cytolytic and Th cells. Optimal induction of 4-1BB mRNA in T cells required both PMA and ionomycin stimulation, indicating that protein kinase C activation and increases in intracellular Ca2+ were required for its expression. 4-1BB was categorized as an early activation gene since the protein synthesis inhibitor, cycloheximide, blocked the induction of 4-1BB mRNA. A rat mAb, 53A2, was generated against recombinant soluble 4-1BB and was used to characterize this molecule. 4-1BB is a 30-kDa glycoprotein and appears to exist as both a monomer and a 55-kDa dimer on the cell surface of a T cell clone. The 4-1BB protein may be post-translationally modified since its predicted backbone is 25 kDa. FACS analysis indicated that 4-1BB was inducible and expressed on the cell surface of activated splenic T cells and thymocytes. Cross-linking of 4-1BB on anti-CD3-stimulated T cells with 53A2 resulted in a dramatic enhancement of T cell proliferation. This suggests that 4-1BB may function as an accessory signaling molecule during T cell activation.

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Amino Acid Sequence Animals Antibodies, Monoclonal Antigens, CD Antigens, Differentiation, B-Lymphocyte Base Sequence CD40 Antigens Female Immune Sera Lymphocyte Activation Mice Mice, Inbred BALB C Molecular Sequence Data Receptors, Antigen, T-Cell T-Lymphocytes Journal Article Research Support, U.S. Gov't, P.H.S.

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K E Pollok, Y J Kim, Z Zhou, J Hurtado, K K Kim, R T Pickard, B S Kwon. 1993-02-01. Inducible T cell antigen 4-1BB. Analysis of expression and function.. https://pubmed.ncbi.nlm.nih.gov/7678621/

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