title: Phenotype and cytolytic activity of mouse tumor-bearer splenocytes and tumor-infiltrating lymphocytes from K-1735 melanoma metastases following anti-CD3, interleukin-2, and tumor necrosis factor-alpha combination immunotherapy.
abstract: We studied the phenotype and antitumor cytolytic activity of splenocytes from mice with K-1735 pulmonary metastases and tumor-infiltrating lymphocytes (TILs) from these metastases following treatment with anti-CD3, IL-2, and TNF combination immunotherapy. Mice were injected with 5 x 10(4) tumor cells and received a single 5 micrograms i.p. dose of anti-CD3 on day 3, followed by either IL-2 alone or fourfold less IL-2 with TNF (25,000 U/day) given at 3-day intervals. A single dose of anti-CD3 followed by low-dose IL-2 and TNF caused the greatest reduction in metastases compared to anti-CD3 alone, higher doses of IL-2 alone, or IL-2 + TNF. Reduction in metastases (greater than 80%) using the three agents was equal to or exceeded that achieved by ninefold higher concentrations of IL-2 alone. Treatment with anti-CD3 + IL-2 and TNF significantly prolonged survival, and resulted in 60% of mice achieving long-term survival greater than 120 days. This was superior to single agents or other combinations with the three agents causing a synergistic rather than additive effect. The anti-CD3-activated splenocytes were a heterogeneous population of T cells, with an increased number of CD8+ cells compared to splenocytes from mice treated with high doses of IL-2 alone. Analysis of TILs showed a greater proportion of CD8+ cells in anti-CD3-treated mice compared to IL-2 alone, but a lower proportion of CD4+ cells. Lymphokine-activated killer (LAK) and natural killer (NK) activities of both splenocytes and TILs in vitro increased following anti-CD3/IL-2 + TNF treatment, and were consistently greater than that generated with four times more IL-2 alone. TNF appeared to potentiate cytolytic activity rather than affect phenotypic changes. These results indicate that the sequential use of anti-CD3, IL-2, and TNF for LAK induction and maintenance potentiates antitumor activity, and suggests novel strategies for combination immunotherapy.
authors.affiliation: Department of Thoracic Surgery, University of Texas M.D. Anderson Cancer Center, Houston 77030.
authors.forename: S C
authors.initials: SC
authors.lastname: Yang
authors.forename: K D
authors.initials: KD
authors.lastname: Fry
authors.forename: E A
authors.initials: EA
authors.lastname: Grimm
authors.forename: J A
authors.initials: JA
authors.lastname: Roth
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D015703:Antigens, CD / Q000276:immunology; D003601:Cytotoxicity Tests, Immunologic; D016130:Immunophenotyping; D007167:Immunotherapy / Q000379:methods*; D007376:Interleukin-2 / Q000627:therapeutic use; D008175:Lung Neoplasms / Q000276:immunology / Q000628:therapy*; D016246:Lymphocytes, Tumor-Infiltrating / Q000276:immunology*; D008545:Melanoma / Q000276:immunology / Q000556:secondary / Q000628:therapy*; D051379:Mice; D011994:Recombinant Proteins / Q000627:therapeutic use; D012074:Remission Induction / Q000379:methods; D013154:Spleen / Q000166:cytology / Q000276:immunology*; D015996:Survival Rate; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000627:therapeutic use
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D007376:Interleukin-2; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha