Mucosal and systemic isotype-specific antibody responses and protection in conventional pigs exposed to virulent or attenuated porcine epidemic diarrhoea virus.

摘要: Eleven-day-old conventionally reared piglets were inoculated orally with two different doses of the cell-culture adapted strain CV-777 porcine epidemic diarrhoea virus (PEDV) or virulent isolate same and challenged PEDV 3 weeks later. Pigs attenuated did not show any typical sign disease, shedding was frequent. In contrast, 31% pigs exposed to developed demonstrated in 100%. At postinoculation day (PID) postchallenge (PCD) virus-specific antibody-secreting cells (ASC) gut associated lymphoid tissues (duodenum ileum lamina propria mesenteric lymph nodes) systemic locations (blood spleen) assessed by enzyme-linked immunospot (ELISPOT). Only a small response detected groups PEDV, whereas group previously on PID 21 large number IgG IgA ASC detected. Isotype-specific antibody responses serum investigated ELISA. all groups, although highest corresponded only this showed an response. The completely protected against challenge higher dose none them shed virus. partially challenge, 25% low dose- 50% high dose-exposed after challenge. All from control group, virus, excreted faeces. A strong positive correlation established between protection blood at also isotype-specific titers that day. addition, correlated found tissues. secondary immune primary evident group. No increase seen parameters studied PEDV.