Anti-CD3 + IL-2-stimulated murine killer cells. In vitro generation and in vivo antitumor activity.
The growth, phenotype, in vitro cytolytic characteristics, and in vivo antitumor activity of murine splenocytes stimulated with anti-murine CD3 mAb in combination with IL-2 as compared with IL-2 alone was investigated. When cultured for 12 days with anti-CD3 mAb + IL-2, murine splenocytes increased 100- to 4000-fold in number compared with only 6- to 20-fold for cultures stimulated with IL-2 alone. Anti-CD3 mAb + IL-2 activated cultures developed high lymphokine-activated killer activity against NK-resistant targets including the P815 mastocytoma cell line and fresh MCA 106 sarcoma. Peak cytotoxicity on a per cell basis developed by day 8 after anti-CD3 mAb + IL-2 activation. A large proportion of the total cytolytic activity of long term anti-CD3 mAb + IL-2-stimulated cultures was related to the presence of anti-CD3 in the assay, indicating enhancement of cytotoxicity by activated CD3+ T cells. Phenotypic analysis indicated that anti-CD3 mAb + IL-2-stimulated cultures contained heterogeneous populations of T cells with increased percentages of both CD4+ and CD8+ phenotypes compared with cultures stimulated with IL-2 alone. Anti-CD3 mAb + IL-2-stimulated cells were tested for their in vivo antitumor activity by using C57BL/6 mice bearing MCA 106 sarcoma pulmonary metastases. IL-2-activated murine killer cells were given in combination with in vivo IL-2 and indomethacin, the latter of which was shown to potentiate the antitumor effect of IL-2. When given on day 5 after tumor inoculation, cell doses as low as 5 x 10(6) anti-CD3 mAb + IL-2-stimulated cells per mouse significantly reduced the number of pulmonary metastases (p less than 0.005). Thus, activation with the combination of anti-CD3 mAb + IL-2 produces rapidly expanding cultures of cytolytic cells with demonstrated in vivo antitumor efficacy.
Anderson
P M
PM
Department of Pediatrics, University of Minnesota, Minneapolis 55455.
Blazar
B R
BR
Bach
F H
FH
Ochoa
A C
AC
D000818:Animals; D000911:Antibodies, Monoclonal / Q000502:physiology* / Q000627:therapeutic use; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology*; D017252:CD3 Complex; D002455:Cell Division; D003602:Cytotoxicity, Immunologic; D005260:Female; D007116:Immunization, Passive; D007376:Interleukin-2 / Q000494:pharmacology* / Q000627:therapeutic use; D007694:Killer Cells, Natural / Q000145:classification / Q000276:immunology* / Q000637:transplantation; D008175:Lung Neoplasms / Q000556:secondary / Q000628:therapy; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D010641:Phenotype; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D012513:Sarcoma, Experimental / Q000628:therapy
D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D007376:Interleukin-2; D011948:Receptors, Antigen, T-Cell