Augmentation by OK-432 of generation of culture-induced killer cells.
A streptococcal preparation, OK-432, injected intraperitoneally, potentiated rejection of L1210 leukemic cells in semiallogeneic BALB/c mice. This increased rejection was further enhanced by a transfer of peritoneal exudate T (PET) cells, but not of spleen cells. Spleen cells incubated in vitro for 3 or more days were as effective as PET cells in stimulating tumor rejection, and were cytotoxic in vitro as tested by a 4-hr 51Cr-release assay. This cytotoxicity was closely related to the OK-432-mediated augmentation of L1210 rejection in vivo. In vitro treatment with OK-432 of spleen cells from intact mice generated nonspecific cytotoxic cells. The cells were nonadherent to plastic, radioresistant, and of Thy-1+, Lyt-1,2-, and asialoGM1+ phenotypes, and were tentatively named OK-432-induced killer (OIK) cells. They were cytotoxic to tumor cells resistant to natural killer (NK) cells, and different from NK cells or lymphokine-activated killer cells. For their generation, macromolecular synthesis and participation of plastic-adherent cells (probably macrophages) were needed. The in vivo growth of L1210 leukemic cells could not be inhibited by simultaneous administration of PET cells primed in vivo with OK-432, of spleen cells primed in vivo with OK-432 and then cultured, or of spleen cells primed in vitro with OK-432 and then cultured (OIK cells). However, a prophylactic adoptive transfer of these cells was effective in immunocompetent mice as well as in athymic nu/nu mice, but not in mice irradiated with 400 rad. The in vivo activity was attributable mainly to Lyt-1+, -2- cells radioresistant and adherent to nylon wool, which were probably amplifier/helper T cells.
Ujiie
T
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Department of Experimental Therapeutics, Kanazawa University, Japan.
D000818:Animals; D001688:Biological Products / Q000494:pharmacology*; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D006084:Graft Rejection / Q000187:drug effects; D007116:Immunization, Passive; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000276:immunology; D007939:Leukemia L1210 / Q000276:immunology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009368:Neoplasm Transplantation; D010844:Picibanil / Q000494:pharmacology*; D013154:Spleen / Q000276:immunology
D001688:Biological Products; D010844:Picibanil