[Expression and gene mutation of cluster of differentiation 9 in lung cancer cells induced by mineral powder in Gejiu].

OBJECTIVE: To investigate the expression and gene mutation of cluster of differentiation 9 (CD9) in the pathway of the mineral powder induced malignant transformation in immortalized human bronchial epithelial cells (BEAS-2B) in Gejiu. METHODS: BEAS-2B cells served as the control group and its malignant transformation cells induced by mineral powder in Gejiu were considered as experiment group. The expression of CD9 protein in 20 bottles of BEAS-2B cells and 20 bottles of malignant transformation cells was evaluated by immunocytochemistry. The mRNA expression of CD9 in 10 bottles of BEAS-2B cells and 10 bottles of malignant transformation cells was examined by reverse transcriptase polymerase chain reaction (RT-PCR). Gene mutation was detected in the products of RT-PCR by DNA sequencing. RESULTS: There was significant difference between the expression of CD9 protein in BEAS-2B cells (100%, 20/20) and that in its malignant transformation cells (35%, 7/20 P < 0.01). The expression of CD9 mRNA in BEAS-2B cells 0.91 +/- 0.09 was significantly higher than that in its malignant transformation cells (0.34 +/- 0.14) (P < 0.01). Two point mutation of CD9 gene was detected in the malignant transformation cells of BEAS-2B by DNA sequencing. The change of G-->T in the base of 231 led to the change of Gln-->His in the amino acids of 40. The change of T-->A in the base of 119 led to the change of Val-->Asp in the amino acids of 3. CONCLUSION: The absence or down-regulation of CD9 expression and point mutation in the malignant transformation cells of BEAS-2B may play a considerable role in the pathway of the malignant transformation in the BEAS-2B cells induced by mineral powder in Gejiu.

[Generation of specific cytotoxicity T lymphocytes induced by tumor-derived heat shock protein 90-peptide complexes in vitro].

OBJECTIVE: To investigate the specific induction of cytotoxic lymphocyte (CTL) by tumor-derived heat shock protein 90-peptide complexes (HSP90-PC). METHODS: Heat shock protein 90-peptide complex (HSP90-PC) was isolated and purified by liquid chromatography after precipitation by 50% - 70% (NH4) 2SO4 saturation from 10 specimens of renal carcinoma resected from 10 patients aged 40 - 60 during operation. The component containing HSP90-PC was filtered and sterilized. The molecular weight and the identity of the purified HSP90-PC were confirmed by SDS-PAGE and Western blotting. 10 - 15 ml peripheral blood was extracted from these patients. T cells were amplified. Flow cytometry was used to detect the phenotype of dendritic cells (DCs). The DCs in the experimental group were cultured for 5 days and then HSP90-PC and tumor necrosis factor (TNF)-alpha was added into the culture. The HSP90-PC pulsed DCs were collected and co-cultured with auto-T cells for 72 hours. Flow cytometry was used to detect the content of CD8(+) T cells. The DC of the control group were mixed directly with auto-T cells and the content of CD8(+) T cells was examined by flow cytometry. RESULTS: The proliferation of T cells co-cultured with the HSP90-PC pulsed DCs was significantly remarkable and the content of CD8(+) CTLs was significantly more in comparison with the control DC (P < 0.01). CONCLUSION: HSP90-PC prepared from tumor tissues has strong immunogenicity and the DC sensitized thereby effectively induces the proliferation of CTL. Application of HSP90-PC provides a new approach in tumor immunotherapy.

[Study on the attenuation of graft versus host disease by methoxy polyethylene glycol modification of donor lymphocytes].

AIM: To find out why mPEG modification of donor's lymphocytes can attenuate the occurrence of graft versus host disease(GVHD), but not affect the hemopoietic reconstitution of stem/progenitor cells after transplanting the mPEG-modified mononuclear cells from human cord blood into the SCID mice. METHODS: The followings were observed: (1) Changes of CD4(+) and CD8(+) T cells and the ratio of CD4(+)/CD8(+) T cells were examined by flow cytometry before and after mononuclear cells from human cord blood were modified with mPEG. (2) The difference in forming the CFU-GM in-vitro between the mPEG modified-stem/progenitor cell group and non-modified cell group was observed. (3) The time of appearance of GVHD and the survival of the SCID mice were observed after the pre- and post-modification mononuclear cells were transplanted. (4) The number of humanized CD45(+) cells in the mouse's bone marrow was detected about 7 weeks after transplantation. RESULTS: (1) mPEG nearly completely covered up the CD4 and CD8 antigens on T cells, while the number of CFU-GM did not show any obvious change between the modified and non-modified cell groups. (2) GVHD appeared later in the modified mononuclear cell group than in the non-modified group, and the survival rate was elevated in the modified group than in the non-modified group. (3) Humanized CD45 cells were found in mouse's bone marrow at the 47th day after transplantation of both mPEG-modified and non-modified mononuclear cells. CONCLUSION: After CD4 and CD8 antigens were covered up with mPEG, the graft's immune response against host was weakened, but the proliferation and differentiation of transplanted hemopoietic stem/progenitor cells were not affected.