Mechanism of action of Abatacept is ( REPAEAT)
Correct Answer: T cell inhibitor
Description: Abatacept is a soluble fusion protein that consists of the extracellular domain of human cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) linked to the modified Fc (hinge, CH2, and CH3 domains) poion of human immunoglobulin G1 (IgG1). Abatacept is produced by recombinant DNA technology in a mammalian cell expression system. The drug has activity as a selective costimulation modulator with inhibitory activity on T lymphocytes. It is used in the treatment of Rheumatoid ahritis. Ordinarily, full T cell activation requires 1) binding of the T cell receptor to the antigen-MHC complex on the antigen presenting cell (APC) and 2) a costimulatory signal provided by the binding of the T cell's CD28 protein to the B7 protein on the APC. Abatacept, which contains a high-affinity binding site for B7, works by binding to the B7 protein on APCs and preventing them from delivering the costimulatory signal to T cells, thus preventing the full activation of T cells. Abatacept is the basis for the second-generation belatacept currently being tested in clinical trials. In organ transplantation, it is intended to provide extended graft survival while limiting the toxicity generated by standard immune-suppressing regimens such as calcineurin inhibitors (eg, ciclosporin). Ref: katzung 12th ed.
Category:
Pharmacology
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now