Anti-CTLA4 Monoclonal Antibody [1E6]

The cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), also known as CD152, is a member of the immunoglobulin superfamily that is expressed by activated T cells and transmits an inhibitory signal to T cells (1,2) . Both it and the homologous T-cell co-stimulatory protein CD28 bind to CD80 (B7-H1) and CD86 (B7-H2) on antigen-presenting cells (APCs) (3) . Mutations in the CTLA-4 gene have been implicated in multiple autoimmune diseases (4) . CTLA-4 also functions as an immune checkpoint protein, and anti- CTLA-4 antibodies have been successfully used in the treatment of cancer (5) .

Widely expressed with highest levels in lymphoid tissues. Detected in activated T-cells where expression levels are 30- to 50-fold less than CD28, the stimulatory coreceptor, on the cell surface following activation.

Inhibitory receptor acting as a major negative regulator of T-cell responses. The affinity of CTLA4 for its natural B7 family ligands, CD80 and CD86, is considerably stronger than the affinity of their cognate stimulatory coreceptor CD28.

CTLA-4 antibody can be stored at 4°C for three months and -20°C, stable for up to one year. Avoid repeated freeze-thaw cycles. Antibodies should not be exposed to prolonged high temperatures.