Monoclonal antibodies to porcine tumor necrosis factor alpha: development of an enzyme-linked immunosorbent assay.

Five hybridomas (4F4, 14H1, 9B4, 6E10, and 8G7) secreting antibodies to porcine tumor necrosis factor alpha (PTNF-alpha) were obtained from one fusion. Four of the 5 monoclonal antibodies (Mab) recognized recombinant PTNF-alpha (rPTNF-alpha) on western blot and were able to neutralize both rPTNF-alpha and native (released by porcine macrophages) PTNF (nPTNF-alpha, only 4F4, 14H1, and 9B4 tested for the neutralization of nPTNF-alpha) in vitro. A sandwich enzyme-linked immunosorbent assay (ELISA) for PTNF-alpha was developed using Mab 4F4 and purified rabbit polyclonal antibodies against PTNF-alpha. The test detected PTNF-alpha concentrations as low as 400 pg/ml and did not cross react with native porcine TNF-beta, recombinant human TNF-alpha, recombinant mouse TNF-beta or native mouse TNF-alpha. The Mabs and the ELISA should be useful for assessing PTNF-alpha levels in swine serum during disease processes and possibly for alleviation of toxic effects of TNF-alpha.