AIM: To observe the effects of high-dose hepatitis B surface antigen (HBsAg) vaccine on cellular immune response in BALB/C mice. METHODS: The mice were immunilized separately with low-dose and high-dose HBsAg vaccine by intramuscular injection two times. The specific proliferative activities of T lymphocytes were measured by [ 3H]-TdR incorporation assay. IL-2 as well as IFN-? levels in the culture supernatant of T cells and anti-HBs IgG2a lever in sera were detected by enzyme-linked immunoabsorbent assay. RESULTS: After first vaccination with high-dose HBsAg, the proliferative activities of T cells in the experimental group were significantly stronger, both levels of IL-2 and IFN-? were markedly higher than that in the control group and the percentage of mice to produce serum anti-HBs IgG2a was significantly higher compared to that of mice immunilized by low-dose HBsAg. All data in experimental groups were further increased after second dose of vaccine. CONCLUSION: Vaccination of mice with high-dose HBsAg can induce cellular immune responses tended to Th1(T helper 1 subset) response.

Glioblastoma (GBM) is the most common and lethal primary neoplasm in the central nervous system. Despite intensive treatment, the prognosis for patients with GBM remains poor, with a median survival of 14-16 months. 90% of GBMs are primary GBMs that are full-blown at diagnosis without evidences of a pre-existing less-malignant precursor lesion. Therefore, identification of the cell(s) of origin for GBM-the normal cell or cell type that acquires the initial GBM-promoting genetic hit(s)-is the key to the understanding of the disease etiology and the development of novel therapies. Neural stem cells and oligodendrocyte precursor cells are the two major candidates for the cell(s) of origin for GBM. Latest data from human samples have reignited the longstanding debate over which cells are the clinically more relevant origin for GBMs. By critically analyzing evidences for or against the candidacy of each cell type, we highlight the most recent progress and debate in the field, explore the clinical implications, and propose future directions toward early diagnosis and preventive treatment of GBMs.