V.A. Chumakov*, I.A. Kachkov*, S.V. Suchkov**
* Moscow Regional Research Clinical Institute, Moscow, Russia
** Sechenov Moscow Medical Academy, Moscow, Russia
Cases with glioblastoma are characterized by secondary immunodeficiency (SID), affecting mainly a cellular link. Our study demonstrated existence of two main clinical- and-immunologic groups of cases with glioblastomas (n=41), i.e. those with syndrome of tumor-associated secondary immunodeficiency (STASID) and those with tumor-associated autoimmune syndrome, combined with secondary immunodeficiency (TAASSID). There were two subphenotypes in the first group: I (n=25) – cases with marked immunodeficiency and II (n=12) – cases with minor immunodeficiency. There were no signs of autoimmune disorders in these subgroups. However, they were watched in blood of patients with TAASSID (n=4) and manifested themselves in presence of antineuronal and antimyelinic serum antibodies, as well as an increased level of markers of B-lymphocytes and immunoglobulins. The content of CD95+-lymphocytes was 2-3 times above the normal value in cases with the STASID I phenotype, whereas the same indices increased not more than by 30-60% in the STASID II phenotype. As for parameters of CD95+/CD3+ and CD95/CD4+ apoptosis, they were respectively 3-5 and 1.5-2 times above the normal value in the first subgroup (phenotype I) and 2 times smaller in the second one (phenotype II). This difference was caused by high apoptotic activity of T-cells in cases with phenotype I. Thus, it is quite possible, that mechanisms of Fas-mediated apoptosis can play an important part in tumor pathogenesis due to apoptopic death of main subpopulations of T-cells, capable of opposing glioblastoma progression. Cases with TAASSID were characterized by lymphocyte apoptosis too. However, it was conditioned by the second signal path, demanding presence of the CD70 marker on glioblasoma cells (a superficial ligand for TNF).
Comparing a histological type of a tumor and immunologic phenotypes of cases with glioblastoma, we have come to a conclusion, that isomorphocellular and polymorpocellular glioblastomas, regarded as severe from clinical and prognostic points of view, are typical of cases with marked immunoregulatory disorders, i.e. of STASID I and TAASSID phenotypes.