Suppressor cell activity triggered by tumor associated antigen in patients with intracranial glioma
Lin, S.M.; Hung, C.C.
Journal of the Formosan Medical Association 85(1): 8-18
1986
ISSN/ISBN: 0371-7682 PMID: 2940327 Document Number: 284858
The present study was conducted to examine, in vitro, the suppressor cell activity induced by the allogeneic soluble glioma-associated antigen (GAA) in patients with intracranial glioma (ICG). Peripheral blood lymphocytes (PBLs) of the ICG patients were pre-incubated with GAA and washed prior to one way mixed-lymphocyte culture (MLC). A significant inhibition of phytohemagglutinin (PHA)-induced lymphocyte mitogenesis of the normal responder lymphocyte in MLC was observed in the majority of the tests performed (44/47 tests). In only 3 tests, the antigen pretreated PBLs from the ICG patients expressed an effect of enhancement. The overall result of the examination in this group of patients was a suppressive response with a mean of 47.6 .+-. 47.3%, which was significantly different (P < 0.01) from the results of those tests similarly conducted in patients with benign intracranial tumor (BICT) and controls. The frequency of suppressor response was only 21/33 for the BICT patients and 22/47 for the controls. The overall result was a weak suppressive response (9.7 .+-. 54.0%) in the BCIT group and, on the contrary, an enhancement (-21.4 .+-. 79.4%) in the controls. However, there were no significant differences among the 3 groups of the patients studied when GAA was substituted by the soluble crude extract of normal brain tissue for the triggering of the suppressor cell activity, the results being enhancement in all 3 groups (-25.2 .+-. 96.1%, -62.3 .+-. 166.3%, -49.2 .+-. 94.3%, respectively). Among the ICG patients, the difference between the results of the tests, in which PBLs were activated either by GAA or by normal brain extract, was highly significant (P < 0.001). The crude extract of meningioma was also tested for comparison, and 14 samples of PBLs from the BICT patients were pretreated by this tumor extract. Although a high magnitude of enhancement (-133.3 .+-. 289.3%) was observed, it was not significantly different (P > 0.05) from the results of a suppressive response (30.8 .+-. 18.3%) in 11 blood samples from ICG patients. The significant GAA-induced suppressor cell activity observed in the majority of ICG patients in the present study may presumably be specific of GAA. These observations have indicated that GAA activates suppressor cells of ICG patients in vitro which could have relevant connections with the in vivo situation. Thus the tumor may release suppressor cell-activating factors to activate the suppressor cells and abrogate the cellular immune response of the host, and it finally results in the rapid growth of the tumor.