An independent study assessing the quality of antibodies to cIAP-1 and cIAP-2 has found R&D Systems products superior to those of several competitors. cIAP-1 and cIAP-2 are members of the inhibitors of apoptosis (IAP) family, best known for their ability to suppress the activity of pro-apoptic caspases. R&D Systems anti-human/mouse cIAP-1 polyclonal antibody (Catalog # AF818) and anti-human cIAP-2 polyclonal antibody (Catalog # AF817) were judged superior based on their ability to provide the clearest signal and least background in immunohistochemistry studĀies using a broad panel of human tissues.