Isolation and Purification of Immunomodulating Protein from Ovis Aries Small Intestine

Abstract

A protein (F1-a) was isolated and purified from sheep small intestine using column chromatography over Sephadex G-25, DEAE-650M, and HW-55F. The protein content was 55.28%; yield, 50.42%; approximate molecular mass, 66 kDa. The amino-acid composition of purified F1-a was determined by HPLC. Its main component was identified by liquid-chromatography–tandem mass-spectrometry (LC-MS/MS). Also, purified F1-a exhibited immunological activity because it was observed to cause a dose-dependent increase in secretion of nitric oxide (NO), tumor necrosis factor α (TNF-α), and interleukin-6 (IL-6) in unactivated RAW264.7 cells.