This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
Abatacept is - 
Select and explain. 
A. TNF alpha inhibitor, B. Inhibitor of co - stimulation of T cells, C. IL - I receptor antagonist, D. Monoclonal antibody against IL - 6 receptor
B: Inhibitor of co - stimulation of T cells
Answer: B: Inhibitor of co - stimulation of T cells 
Explanation: Ans. is 'b' i.e., Inhibitor of co-stimulation of T cells o Abatacept inhibits the co - stimulation of T cells by blocking CD28 - CD80/86 interactions and also inhibits the function of antigen presenting cells by reverse signalling through CD80 and CD 86.