T subsets and antitumor activity of lymphocytes infiltrating human primary brain gliomas

Abstract

Glioma-infiltrating lymphocytes (GIL) were isolated from 9 surgical biopsy specimens of primary brain gliomas using mechanical and enzymatic digestion and discontinuous density gradent centrifugation. During cultured in the presence of interleukin-2 (IL-2) for a period of four weeks, GIL were expanded 48. 4-fold on the average, even up to 118-fold. GIL activated by IL- 2 had specific cytolytic activity against autologous glioma cells. Analysis of T subsets of GIL freshly isolated showed that CD 3 + cells were 71. 0±11. 9% , CD 4 + cells 34.2±6.1% and CD 8 + cells 37. 07. 6%. Ability of activated GIL to produce γ-interferon (γ-IFN) was significantly higher than that of freshly isolated GIL and autologous peripheral blood lymphocytes (PBL). The results suggest that GIL have many advantages for an adoptive immunotherapy of patients with brain gliomas and be a new type of antitumor immune effector.