OBJECTIVETo investigate the possibility of using melanoma antigen-1 (MAGE-1) peptide as a tumor vaccine to treat hepatocellular carcinoma (HCC).

METHODSThe expressions of MAGE-1 in 8 HCC cell lines and in liver cancer tissue from a patient were detected using RT-PCR. The type of human leucocyte antigen I(HLA I) of both 8 HCC cell lines and peripheral blood mononuclear cells of the patient was detected using a microcytotoxicity method to screen out target cell lines for the cytotoxicity assay. Peripheral blood mononuclear cells from the HCC patient pulsed with an MAGE-1 peptide (NYKCRFPEI) were used as antigen presenting cells. Autogenous peripheral blood mononuclear cells were stimulated with antigen presenting cells every 7 days for 4 times to elicit cytotoxic T lymphocytes. The phenotype of effector cells was analyzed using flow cytometry. The cytotoxicity of effector cells was detected with a lactate dehydrogenase releasing assay.

RESULTSThe expressions of both MAGE-1 and HLA-A24 were detected in BEL7405 cell line which were used as the positive target cell line in the cytotoxicity assay. The expression of MAGE-1 alone was detected in HLE, BEL7402, BEL7404, QGY7703 and SMMC7721 cell lines, and the expression of neither MAGE-1 nor HLA-A24 was shown in QGY 7701 and HpG2 cell lines. The last 7 cell lines could be used as negative target cell lines in the cytotoxicity assay. Peripheral blood mononuclear cells expanded 32 folds during 28-day culture. The ratio of CD3(+) T cells increased by 16% (from 54% to 70%), and the ratio of CD8(+) T cells increased by 20% (from 36% to 56%) during 28-day culture. When the ratio of effector cells to target cells was 10:1, effector cells exhibited 62.5% cytotoxicity against autogenous lymphoblasts pulsed with the peptide (NYKCRFPEI) of MAGE-1 antigen, 40.25% cytotoxicity against BEL7405 cells, compared with 17.88% cytolysis observed against autogenous lymphoblasts, 19.55% against HLE cells, and 1.6% against QGY7701 cells. When the ratio of effector cells to target cells was 3.3:1, the cytotoxicity of effector cells against the peptide pulsed autogenous lymphoblasts was 53.6%, which was much higher against autogenous lymphoblasts, HLE cells and QGY7701 cells at 15.6%, 13% and 1%, respectively.

CONCLUSIONThe results demonstrate that cytotoxic T lymphocytes with the ability to specifically lyse target cells expressing both MAGE-1 and HLA-A24 could be successfully induced by the MAGE-1 peptide NYKCRFPEI in vitro. This indicates that a good result might be anticipated if this peptide is used as a tumor vaccine to treat HLA-A24 HCC patients.

Adult ; Antigens, Neoplasm ; Cancer Vaccines ; immunology ; Carcinoma, Hepatocellular ; immunology ; HLA-A Antigens ; analysis ; HLA-A24 Antigen ; Humans ; Liver Neoplasms ; immunology ; Male ; Melanoma-Specific Antigens ; Neoplasm Proteins ; genetics ; immunology ; RNA, Messenger ; analysis ; T-Lymphocytes, Cytotoxic ; immunology ; Tumor Cells, Cultured

Objective To understand the current situation of tuberculosis (TB) prevention and control in schools, and to provide a basis for further improving school TB prevention and control strategies. Methods A survey of 387 schools in Tianjin was conducted. The data was statistically analyzed by chi-square test. Results Most of the schools implemented the TB prevention and control work well, including leadership responsibility, work plan and epidemic report. However, the leadership responsibility (72.34%, 34/47) and the work plan (68.09%, 32/47) in colleges and universities were not well implemented. The proportion of full-time health care personnel in schools with more than 600 students was relatively low, which was 1:2 497 in primary schools, 1:1 537 in secondary schools, and 1:2 673 in colleges and universities. The proportion of morning and afternoon checking (27.66%) and sickness absenteeism tracking (82.98%) was low in colleges and universities. There was a lower proportion of new students carrying out TB test in primary schools and secondary schools (χ²=26.05，P<0.001). The colleges and universities had a low proportion of TB check-up among students in schools and students in high epidemic areas (P<0.001). The screening rate of students who had close contacts with TB patients in primary schools was low (P<0.001). The proportion of preventive treatment in schools at all levels was low (P<0.001). Conclusion Schools at all levels in Tianjin need to utilize additional school health care personnel and increase the proportion of latent infection patients receiving preventive treatment. Primary and secondary schools should further standardize the physical examination of new students and the treatment of epidemic situation. It is necessary for colleges and universities to establish multi-level tuberculosis surveillance networks and carry out active screening.

Objective To further investigate the expression of MAGE-1 gene in hepatocellular carcincma (HCC). Methods The tumors and adjacent liver tissue from 45 HCC patients and liver tissue from 28 non-HCC patients (16 with liver cirrhosis and 12 with normal liver) were characterized by RT-PCR. A 421 bp PCR product from a cDNA fragment spanning exons 1,2 and 3 was sequenced. The HLA type wes assayed by standard ELISA in 43 HCC patients. Results Thirty-two of 45 tumor tissues from HCC patients expressed MAGE-1 mRNA (71.1%).In contrast, MAGE-1 mRNA was not detected in adjacent tissues. Three were found to have point mutations at 3 idntical sites resulting in the substitution of two amino acid residues.The most frequent HLA types in 43 HCC patients were: HLA-A2, 53.5%; A11, 25.6%; A24, 20.9%; A33, 20.9%; HLA-B13, 28.3% and B35, 23.2%. Expression of HLA-A33 (20.9%) was higher in HCC patients than that predicted in the normal Chinese population (8.8%). There was no discemable correlation between MAGE-1 expression and α-FP level, tumor size and hepatitis B or C virus infection.The identification of peptides which are restricted by haploptypes other than A1 should increase the opportunity for paptide based immunotherapy. Conclusions This study shows that MAGE-1 mRNA is highly expressed in HCC tumor tissue in Chinese patients. Previously unreported point mutations in the MAGE-1 gene are described and may also provide additional opportunities for immunotherapy.