Functional analysis and induction of four novel goose (Anser cygnoides) avian β-defensins in response to salmonella enteritidis infection

In the current study, four novel avian beta-defensins (AyBDs) (AvBD2, 5, 9, and 10) were identified in tissues from the Chinese goose (Anser cygnoides). The antibacterial activity of the AyBDs showed that all of these AyBDs exhibited antibacterial activity against most of the bacteria investigated (P < 0.01). In addition, antibacterial activity of all of the AyBDs against Staphylococcus aureus and Pasteurella multocida decreased significantly or was completely abolished at 150 mM NaCl (P < 0.01). None of the AyBDs showed hemolytic activity. AyBD2 and AyBD10 were expressed widely, whereas AyBD5 and AyBD9 mRNAs were expressed in a limited number of geese tissues. AyBD9 was significantly induced in some immune tissues from geese after Salmonella enteritidis infection. The others were significantly upregulated in small intestine and some immune tissues of the geese (P < 0.01). The present results suggest that the AyBDs are part of the host defense mechanism of the goose. (C) 2012 Elsevier Ltd. All rights reserved.