Submitted to: Poultry Science Association
Publication Type: Peer reviewed journal
Publication Acceptance Date: 9/27/2001
Publication Date: N/A
Citation: Interpretive Summary: Inflammation is associated with many disease processes. It can be induced experimentally using a variety of noxious stimuli. To understand inflammation induced changes in birds, we injected male broiler chickens with croton oil. The changes induced in blood cell populations and serum protein profiles were studied. We found that inflammation increase serum levels of some proteins while decreased others. Using different biochemical and immunological methods, we identified one of the serum proteins that increased significantly during inflammation as ovotransferrin, which can be used as dianostic marker.
Technical Abstract: Inflammation is associated with a variety of cellular injuries resulting from infections, toxicosis, and physical trauma. It is a complex physiological process. To understand the inflammation-induced changes in birds, 4-wk-old male broiler chickens were subjected to experimental inflammation using a subcutaneous injection of croton oil with changes in serum measured over time and compared with birds treated similarly with olive oil (control). Croton oil treatment significantly elevated blood serum interleukin (IL)-6 levels by 6 h and heterophil counts by 16 h post- injection, which returned to the control levels at 16 h and 24 h, respectively. Croton oil treatment affected the serum protein profiles as assessed by SDS-PAGE and densitometric analyses. Compared with olive oil- treated or normal chicken sera, there were increases in the density of protein bands corresponding to MW of 42 -, 65-, 200-, and 219-kDa, and decreases in bands corresponding to 49 kDa (serum albumin) and a 56 kDa protein in chickens treated with croton oil. Most of these changes were evident at 24 h and lasted through 48 h. The 65 kDa protein was characterized using two dimensional gel electrophoresis and N-terminal sequence analyses. A sequence similarity search in GenBank data base using the first 22 amino acids yielded a complete homology with chicken ovotransferrin. Western blot analysis using anti-chicken serum transferrin and anti-chicken ovotransferrin antibodies also confirmed the 65 kDa protein band to be ovotransferrin. The 65 kDa chicken ovotransferrin, under reducing conditions, showed a MW corresponding to approximately 76 kDa. This study shows that ovotransferrin is a major acute phase protein in chickens.