[Immunodepression during experimental Naegleria meningoencephalitis in mice]

In order to test the function of lymphocytes in Naegleria fowleri-infected mice, the in vitro blastogenic response of splenocyte cultures to non-specific mitogens was studied. Concanavalin A and lipopolysaccharide stimulation were used as tests of T cell and B cell function. For the first 14 days following N. fowleri infection, lymphoblastic transformation induced by T-cell mitogen was markedly reduced in comparison to the uninfected control mice. The blastogenic response to B-cell mitogen remained depressed in the infected mice up to 14 days after infection. The fluorescent antibody titers of sera of N. fowleri infected mice were between 1:4 and 1:32. The results suggest that there is a suppression of cell mediated immunity during the acute course of experimental Naegleria meningoencephalitis in mice.