Abstract
The most striking feature of the infection with Hymenolepis nana is the fact that a tissue phase of infection, which takes place in direct cycle after eggs are fed to mice, ac-companies onset of a high degree of immunity against subsequent infection. Rabbit anti-mouse thymocyte serum (ATS) completely abolished the acquired immunity of primary infected mice against challenge infection with eggs of H. nana, when injected intraperitoneally on days -2, -1, 0, 1, 2 and 3 relative to initial infection. ATS apparently produced its immunosuppressive effect without reacting with mouse serum proteins as judged by immunoelectrophoresis. Rabbit anti-mouse lymphocyte serum (ALS) raised in response to cells from the spleen, thymus, thoracic node, mesenteric node and inguinal node could not produce such an immunosuppressive activity on the acquired immunity. Differences between ALS and ATS were discussed, especially from the viewpoint of preparation method of these two kinds of sera.
As mentioned above, the demonstration that the ATS enhances susceptibility in mice to H. nana seem to place the infection mechanism in the same category as others in which cellular immunity dominates over humoral effects.
