Peroral vaccination with a temperature-sensitive mutant (HVJ-pB) of parainfluenza type 1 virus against respiratory tract infection

野生型仙台病毒的强毒株在鼻内接种时在小鼠的肺中生长并引起病毒性肺炎。然而，在经口接种的小鼠的肺中没有发现野生型病毒生长。来自仙台病毒携带者培养物的温度敏感（ts）突变体可以在32摄氏度繁殖，但不能在34摄氏度以上繁殖，甚至对新生婴儿也没有致病性。口服ts突变体可诱导小鼠产生特异性免疫应答，并保护小鼠免受野生型病毒重叠感染引起的肺炎。紫外线照射ts突变体不诱导保护性免疫。将ts突变体通过管直接滴注到胃中对于wt病毒的疫苗接种是无效的。这些结果表明ts突变体在口腔粘膜中表达病毒蛋白，并在消化道中建立粘膜免疫。通过共同的粘膜免疫系统，呼吸道中的粘膜也变得对野生型病毒攻击免疫。

The virulent strain of wild-type (wt) Sendai virus grows in the lung of mice when inoculated intranasally and causes viral pneumonia. However, no wt virus growth is found in the lung of mice inoculated perorally. A temperature-sensitive (ts) mutant derived from an Sendai virus carrier culture can multiply at 32ﾟC,but not at over 34ﾟC,and shows no pathogenicity to even newborn babies. Oral administration of the ts mutant induces mice a specific immune response and protects from pneumonia caused by the wt virus superinfection. Ultraviolet-irradiated ts mutant induces no protective immunity. A direct instillation of the ts mutant into the stomach through a tube is ineffective for a vaccination against the wt virus.These results indicates the ts mutant expresses viral proteins in oral mucous membrane and establishes mucosal immunity in the alimentary tract. By the common mucosal immune system mucous membrane in the respiratory tract also becomes immune from the wt virus challenge.