Investigation of factors affecting growth ability of avian influenza viruses in pigs

点击翻译按钮获取中文摘要

Pigs are susceptible to type A influenza viruses of avian origin. However, influenza viruses transmitted from wild birds to pigs in nature were not always maintained in pig populations for long time. Adaptation of avian viruses to pigs may require acclimation to low temperature. Temperatures of intestinal tract in aquatic birds and upper respiratory tract in pigs where influenza viruses initiate replication are about 41 and 37 degrees C, respectively. To identify factors affecting the growth ability of avian viruses in pigs, avian viruses were repeatedly infected at low temperature to epithelial cells isolated from porcine lung. Comparative sequence analysis showed that several non-synonymous substitutions in the genes constituting of ribonucleoprotein complex and HA genes were occurred in the low-temperature adapted avian viruses. These observations suggested a possibility that the polymerase activity and HA protein could affect the growth ability of avian influenza virus in pigs.