Derivation of tumor-specific cytolytic T-cell clones from two lung cancer patients with long survival

We derived lung carcinoma cell lines from tumor material resected from a pa tient with small-cell lung cancer (SCLC) and from a patient with non-small- cell lung cancer (NSCLC). The patient with NSCLC was vaccinated with irradi ated autologous tumor cells. The two patients enjoyed an exceptionally favo rable clinical evolution and are currently without signs of cancer 10 and 8 yr after their diagnoses, respectively. Autologous mixed lymphocyte-tumor cell cultures (MLTC) were produced with blood lymphocytes stimulated with i rradiated autologous tumor cells. The first patient's SCLC cells, which car ried a small amount of human leukocyte antigen (HLA) class I molecules, wer e incubated with interferon-gamma (IFN-gamma) before being used as stimulat or cells. A cytolytic T-lymphocyte (CTL) clone was derived that specificall y lysed the IFN-gamma-treated SCLC cells but did not lyse untreated tumor c ells or autologous lymphoblasts. Clones of autologous tumor-specific CTL, d irected against the NSCLC cells of the other patient, were also obtained. T hese tumor cells carried a higher level of HLA class I molecules and were l ysed by the CTL without incubation with IFN-gamma. Altogether, these result s indicate that SCLC and NSCLC cancer cells can be recognized by autologous CTL, and might therefore be susceptible to specific immunotherapy.