Monoclonal antibodies against bovine growth hormone

Immunized spleen lymphocytes were fused with Balb/c mouse myeloma cells to obtain hybridoma cell line 4B-2, which produces monoclonal antibodies (McAb) against bovine growth hormone (bGH). Balb/c mice were injected with 4B-2 cells to produce ascites antibodies. The specific McAb in the ascites (about 10 mg/ml, subclass IgG1) was purified by immunoaffinity chromatography (IAC) on bGH-Sepharose 4B. This McAb cross-reacted with porcine growth hormone (pGH) but not with human (hGH), ovine (oGH), or fish (fGH) growth hormone. A 17 mg portion of purified McAb, coupled to the IAC affinity column was used to purify 1 mg of bGH. The bGH preparation retained its activity in rabbit liver receptor assay and in the tibia test following IAC.