CROSS-REACTIVITY OF HUMAN TOXOPLASMA-SPECIFIC T-CELLS - IMPLICATIONS FOR DEVELOPMENT OF A POTENTIAL IMMUNOTHERAPEUTIC OR VACCINE

Previous reports from this laboratory have demonstrated that human CD4 (+) Toxoplasma-specific cytotoxic T cell (CTL) clones generated by sti mulation of peripheral blood mononuclear cells with Toxoplasma RH stra in antigens also recognized target cells expressing C strain antigens, To extend these observations, additional Toxoplasma isolates were stu died, A simple system for assessment of cytotoxicity using T cell line s rather than cloned CTL was used, Stimulation of human peripheral blo od mononuclear cells with Toxoplasma RH strain antigens elicited cytot oxic T cell lines specific for target cells expressing antigens derive d from many other Toxoplasma strains, Cell lines produced by stimulati on with antigens derived from the related, nonpathogenic coccidian Bes noitia jellesoni were also cytotoxic for target cells expressing Taxop lasma antigens, Proliferative responses to many Toxoplasma isolates an d to the Toxoplasma p30 protein were also noted.