Egg white derivatives induce tumor necrosis factor-alpha expression in porcine peripheral blood mononuclear cells.
Porcine PBMC derived phagocytic activity in peripheral blood polymorphonuclear cells (PMN) induced by egg white derivatives (EWD) treatment was analyzed at the protein and mRNA level. EWD alone failed to induce phagocytic activity of PMN measured by flow cytometry. But PMN phagocytosis was enhanced by culture supernatant from PBMC treated with EWD, human (h)rTNF-alpha and porcine (p)rIL-1beta, respectively. To identify this phagocytic inducing factor, the culture supernatant was partially purified by gel filtration. Only fraction 8 revealed the enhanced PMN phagocytic activity. This fraction also had a high cross-reactivity with anti-prTNF-alpha polyclonal (p)Ab but not with anti-prIL-1beta pAb, as measured by ELISA, indicating that the culture supernatant from PBMC treated with EWD was independent from IL-1beta. The enhanced PMN phagocytic activity of fraction 8 was also inhibited by anti-prTNF-alpha pAb. Both fraction 8 and hrTNF-alpha produced a single protein band between 16 and 18kDa upon analysis by sodium-dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting using anti-prTNF-alpha pAb, suggesting that the promoter of PMN phagocytosis is TNF-alpha, a 16-18 kDa protein produced by EWD-stimulated PBMC. Porcine TNF-alpha mRNA expression in porcine PBMC analyzed by RT-PCR was also increased by addition of EWD. This study strongly suggests that the immunoenhancing effect of EWD on the phagocytic response of porcine PMN is mediated through TNF-alpha produced by PBMC stimulated with EWD. In addition, the expression of porcine TNF-alpha on PBMC is also increased when stimulated with EWD.
Yang
Mhan-Pyo
MP
Laboratory of Veterinary Internal Medicine, Department of Veterinary Medicine, College of Veterinary Medicine and Research Institute of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361-763, Republic of Korea. mpyang@cbnu.ac.kr
Ko
In-Kyung
IK
Kang
Ji-Houn
JH
Song
Deok-Ho
DH
Lee
Geun-Shik
GS
Jeung
Eui-Bae
EB
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D002478:Cells, Cultured; D004527:Egg Proteins / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects; D007375:Interleukin-1 / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects* / Q000276:immunology*; D010587:Phagocytosis / Q000187:drug effects* / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D013552:Swine; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis* / Q000494:pharmacology / Q000502:physiology
D000276:Adjuvants, Immunologic; D004527:Egg Proteins; D007375:Interleukin-1; D012333:RNA, Messenger; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha