Enhanced expression of TGF尾 protein in lymphoid organs and lung, but not in serum, of pigs infected with a European field isolate of porcine reproductive and respiratory syndrome virus
摘要
Transforming growth factor 尾 (TGF尾) is an immunomodulatory cytokine which is able to modulate the host immune response eliciting an inefficient response against pathogens. In this sense, the role of this cytokine in porcine reproductive and respiratory syndrome (PRRS) has been poorly studied and the reported results are contradictory. Thus, in the present study, the expression of TGF尾 was analysed both at tissue (lymphoid organs and lung) and serum level to study its correlation with the expression of PRRS virus (PRRSV). To carry out this study, 32 pigs were inoculated with the European PRRSV field isolate 2982 and sequentially killed from 0 dpi to the end of the study (24 dpi). Blood and tissue samples were collected to determine the expression of PRRSV and TGF尾. PRRSV was detected in inoculated animals from 3 dpi until the end of the study, however TGF尾 was not detected in sera from inoculated animals. Contrary, an increase of TGF尾 antigen was observed both in the lymphoid organs and in the lung of PRRSV-inoculated pigs when compared with control group. Since TGF尾 play a role as an immunomodulatory cytokine of the immune response and also in the differentiation of regulatory T cells (Tregs), the upregulation of the TGF尾 at tissue level may play a role in the impairment of the host immune response observed during PRRS, being observed a significant correlation between PRRSV and TGF尾 expression at lung level.