COMPARATIVE PHENOTYPIC ANALYSIS OF LYMPH-NODE CELLS IN MICE AFTER INFECTION OR VACCINATION WITH NORMAL OR ULTRAVIOLET-ATTENUATED CERCARIAE OF SCHISTOSOMA-JAPONICUM OR SCHISTOSOMA-MANSONI

Mice were infected with 200 untreated or vaccinated with 500 ultraviol et-attenuated cercariae of either Schistosoma japonicum or S. mansoni. Ebr three weeks, cell numbers in axillary and mediastinal lymphnodes were counted and cell populations typed by cytofluorometry. In the axi llary lymphnodes, numbers of B-cells and CD3(+) CD4(+) T-cells but not CD3(+) CD8(+) T-cells increased Following vaccination with either spe cies, parasite migration was apparently delayed in the skin and interr upted at the lungs, the lymphnodes gained weight, and cell numbers of axillary lymph nodes increased more than after infection. In mediastin al lymphnodes, only immunization with S. japonicum bur not S. mansoni cercariae led to an increase of CD3(+) CD4(+) T-cells. Following infec tion, both schistosome species induced higher CD3(+)CD4(+), but not CD 3(+)CD8(+) T-cells in mediastinal nodes, find the peak was earlier wit h S. japonicum (about seven days after infection) than with S. mansoni (about 10 days). In analogy to T-cell observations by others using a gamma-attenuated cercarial vaccine in S. mansoni, the present results suggest that CD3(+)CD4(+) cells also play a role in the ultraviolet-at tenuated vaccine against S. japonicum.