Intestinal cellular immunity after primary rotavirus infection

Infection of neonatal gnotobiotic lambs with a bovine strain of rotavirus was used to characterize the kinetics of the primary cellular intestinal immune response to this agent. At 2–3 days after infection virus was first detected in the faeces and increased numbers of CD45R + cells were observed in peripheral blood. These cells persisted in significantly increased numbers in the circulation until 7–8 days after infection. At this time, virus was no longer detectable in the faeces. The increase in CD45R + cells preceded the appearance of virus-neutralizing antibodies in the serum at 1 week after infection. Maximal antibody titres were reached 2 weeks after infection. Virus-primed cells were first observed 1 week after infection in the jejunal and ileal Peyer's patches, mesenteric lymph nodes and peripheral blood, and persisted in the mesenteric lymph nodes and jejunal Peyer's patches for a further 4 weeks. Analysis of lymphocyte surface antigens indicated that different sub-populations of lymphocytes were responding in the various lymphoid tissues; a majority of CD4 + cells was observed in the mesenteric lymph nodes, whereas B cells predominated in the ileal Peyer's patches.