Polysaccharide Nucleic Acid of Bacillus Calmette Guerin Modulates Th1/Th2 Cytokine Gene Expression in Lipopolysaccharide-Induced Mastitis in Rats

• Published in: Agricultural sciences in China Vol. 8; no. 8; pp. 1010 - 1018
• Main Authors: MIAO, Jin-feng, ZHANG, Yuan-shu, HUANG, Guo-qing, MA, Hai-tian, ZOU, Si-xiang, ZHU, Yu-min
• Format: Journal Article
• Language: English
• Published: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, P.R.China%Institute of Animal Science and Veterinary Medicine, Shanghai Academy of Agricultural Sciences, Shanghai 201106, P.R. China 01.08.2009
• Subjects: Th1/Th2; BCG-PSN; rat mastitis; lipopolysaccharide
• ISSN: 1671-2927
• DOI: 10.1016/S1671-2927(08)60308-9

S1; The aim of this study was to evaluate, in rats, the changes in the T helper type 1 (Th 1)/Th2 radio in mammary glands after an intramammary infusion of lipopolysaccharide (LPS) and to characterize the moderating effects of the polysaecharide nucleic acid of Bacillus Calraette Guerin (BCG-PSN) on the mammary gland. In the control group, the levels of IL-2 and INF-γ, mRNA expression increased, whereas IL-4 mRNA expression decreased after LPS challenge. As a consequence, the INF-γ/IL-4 mRNA ratio was significantly higher at 3, 6, and 9 h post-infusion (PI) compared to the control value (O h; P<0.01).BCG-PSN increased mRNA expression of both INF-γ' and IL-4 before infusion of LPS. LPS challenge significantly the reduced Th1/Th2 eytokine ratio due to Th1 cytokine IFN-γ suppression and Th2 cytokine IL-4 upregulation compared with the control group. A significant reduction ofN-acety1-β-D-glucosaminidase (NAGase) was observed at 24 h PI in the BCG-PSN treatment group compared to the control group (P<0.05). Thus, it was demonstrated that level of BCG-PSN might change the Th1/Th2 ratio mainly by enhancing the Th2 immune response. This is the first report of a Th1/Th2 change induced by coliform mastitis and characterization of the effect of BCG-PSN on mammary gland inflammation. This study makes a better understanding of the mechanisms of coliform mastitis and provides a putative novel strategy for the prevention and/or treatment of mastitis.