The monkey TNF-α ELISAPRO kit provides all necessary reagents and solutions required to quantify TNF-α from non-human primates in solution, e.g. in cell culture supernatant, and serum/plasma samples. The kit contains ELISA plates pre-coated with monoclonal capture antibody, biotinylated detection antibody, Streptavidin-HRP, TMB substrate, ELISA standard and ELISA diluent. The ELISA diluent prevents false positive read-outs which may be caused by heterophilic antibodies found in serum and plasma samples.