Gut mucosal lymphocyte subpopulations in the host-defence of Shigella infected guinea-pigs.

Lymphocyte subpopulations from the gut mucosa were studied in Shigella-susceptible guinea-pigs to evaluate their role in mucosal immune responses to such organisms. Four weeks after infection, isolated lymphocytes were characterised by an immunofluorescent technique. The increase in the T cell intra-epithelial population was less (48%) in comparison to that in normal uninfected animals (74%). On the other hand, Ig bearing B cells in the lamina propria showed an increased incidence and more than 15% of the total mucosal lymphocytes lacked any surface marker, which indicated that they were non-T and non-B cells. A significant rise in the intraepithelial T cell population (P less than 0.01) was observed 6 weeks after infection in comparison to that observed after 4 weeks.