Therapeutic efficacy of Th1 and Th2 L-selectin-CD4+tumor-reactive T cells

Objective: To evaluate the cytokine secretion profile and therapeutic effic acy of Th1 CD4+ L-selectin-tumor-draining Lymph node lymphocytes in the tre atment of murine pulmonary metastases, Study Design: prospective, murine in vivo and in vitro study. Methods: B6 mice were injected bilaterally subcut aneously with MCA 205 sarcoma cells to initiate tumor growth. Eleven days l ater, tumor-draining inguinal lymph nodes were harvested. Single-cell suspe nsions were prepared and fractionated using magnetically activated cell sor ting. Sorted CD4+ L-selectin- lymphocytes were activated with anti-CD3 mono clonal antibody for 48 hours either alone to give a Th1 phenotype, or in th e presence of interleukin (IL)-4 and anti-interferon-gamma (alpha-IFN-gamma ) monoclonal antibody to elicit a Th2 phenotype. Activated cells were then expanded for 3 days in IL-2. Resulting cells were used to treat 3-day pulmo nary metastases, Enzyme-Linked immunosorbent assay and intracellular fluore scent-activated cell-sorter (FACS) scanning were used to evaluate the cytok ine secretion profiles of these cells. Results: Activated and expanded L-se lectin- CD4+ T cells demonstrated a Th1 cytokine profile and excellent anti tumor efficacy. in contrast, L-selectin- CD4+ lymphocytes activated in the presence of IL-4 and alpha-IFN-gamma monoclonal antibody demonstrated a Th2 -like profile and significantly (P <.05) poorer antitumor efficacy. Conclus ions: The cytokine environment during the activation of tumor-draining lymp h nodes can influence the therapeutic efficacy of activated L-selectin- CD4 + T cells. Cell mediated, Th1-dependent immunity appears to play an importa nt role in mediating tumor regression. Culture conditions promoting Th2 cel ls resulted in T cells associated with diminished antitumor efficacy.