In vivo interaction between Trypanosoma gambiense and leucocytes in mice.

Naturally occurring phagocytosis of Trypanosoma gambiense by mouse eosinophils and neutrophils was reported. In vivo and in vitro experiments using monoclonal antibodies confirmed that the phagocytosis is triggered by G1 class antibodies against variable surface antigen. Ultrastructural observation revealed the mode of entry and the intracellular fate of T. gambiense: initial attachment, pseudopodia formation and complete invagination. This phagocytosis resulted in the killing of T. gambiense by mouse eosinophils and neutrophils, suggesting that eosinophils and neutrophils give at least partial protection against infection with T. gambiense in combination with the specific antibodies.