IL-4 regulation of murine lymphokine-activated killer activity in vitro. Effects on the IL-2-induced expansion, cytotoxicity, and phenotype of lymphokine-activated killer effectors.
The in vitro incubation of B6 splenocytes with purified, mouse rIL-4 for 4 to 5 days was sufficient to generate lymphokine-activated killer (LAK) activity. In addition, rIL-4 augmented LAK cytotoxic activity when combined with rIL-2, as measured in a 4 h 51Cr-release assay against fresh, syngeneic MCA-sarcoma (MCA-102 and MCA-105) cells. Interestingly, this augmentation was not observed against the cultured YAC-1 target. LAK generation and augmentation of cytotoxicity by rIL-4 was species-specific, because human rIL-4 (up to 20,000 U/ml) failed to elicit these effects in the mouse splenocyte cultures. When 5-day B6 LAK cells (splenocytes incubated in rIL-2 at 1000 U/ml for 5 days) were split and recultured in the combination of rIL-2 plus rIL-4 for 4 additional days at least a twofold greater expansion in cell number resulted compared to similar cells cultured in either rIL-2 or rIL-4 alone. Moreover, LAK cells expanded in rIL-2 plus rIL-4 exhibited substantial increases in in vitro cytolytic activity (on a per cell basis) against MCA-102 and MCA-105 sarcoma cells, but not against YAC-1 targets. FACS analysis or negative selection using Lyt-2 or NK-1.1 mAb plus C revealed no differences in effector phenotype(s) of LAK cells expanded in rIL-2 alone compared to rIL-2 plus rIL-4 to account for the differences observed in both expansion and cytolytic activity by rIL-4. The majority of cells was Thy-1+, Lyt-2+, T3+, and ASGM-1+. However, a marked increase in the granule-associated serine esterase, BLT-E, was found only in LAK cells expanded in the combination of both lymphokines. Collectively, these studies show that rIL-4 has potent regulatory activities on splenic LAK generation, expansion, and cytotoxic function in the mouse.
Surgery Branch, National Cancer Institute, Bethesda, MD 20892.
J J
JJ
Mulé
J A
JA
Krosnick
S A
SA
Rosenberg
D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000818:Animals; D000911:Antibodies, Monoclonal; D000950:Antigens, Ly / Q000276:immunology; D000954:Antigens, Surface / Q000032:analysis / Q000276:immunology; D003601:Cytotoxicity Tests, Immunologic; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D004338:Drug Combinations; D005260:Female; D053804:Granzymes; D007376:Interleukin-2 / Q000494:pharmacology*; D015847:Interleukin-4; D007378:Interleukins / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000145:classification / Q000201:enzymology / Q000276:immunology*; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D010641:Phenotype; D011994:Recombinant Proteins / Q000494:pharmacology; D012697:Serine Endopeptidases / Q000378:metabolism; D013045:Species Specificity
D000276:Adjuvants, Immunologic; D000911:Antibodies, Monoclonal; D000950:Antigens, Ly; D000954:Antigens, Surface; D004338:Drug Combinations; D007376:Interleukin-2; D007378:Interleukins; D011994:Recombinant Proteins; D015847:Interleukin-4; D053804:Granzymes; D012697:Serine Endopeptidases; C509212:GZMA protein, human