[Treatment of refractory leukemia by combined chemotherapy and halpotype lymphocytes infusion].

BACKGROUND & OBJECTIVE: The complete remission of refractory leukemia treated with conventional chemotherapy is below 50 percent. The high dose chemotherapy can cause more mortality of patients with refractory leukemia. Cytolysis of leukemia cells induced by halpotype lymphocytes was observed in vitro in our previous experiment. In order to improve the complete remission of refractory leukemia and decrease the complication of chemotherapy,the authors treated the patients with refractory leukemia by combined chemotherapy and halpotype lymphocytes infusion and to assess the therapeutic effects and the side effects of this modality. METHODS: Sixteen patients with refractory leukemia were treated by combined chemotherapy. Halpotype lymphocytes irradiated by 7.5 Gygamma radial were infused when patient's white cells count was at the lowest after the chemotherapy. A mean number of 1x10(8)/kg (range:0.8-1.2x10(8)/kg) of halpotype lymphocytes irradiated by 7.5 Gygamma radial was infused. The side effects of infusion of halpotype lymphocyte and completed remission rate were observed. RESULTS: Out of thirteen patients with refractory acute non-lymphocyte leukemia, eleven cases got complete remission and two partial remissions. Out of three patients with refractory acute lymphocyte leukemia, two got complete remission and one no reaction. The total remission rate was 81.2%. No severe side effects and no transfusion related graft versus host disease was observed. CONCLUSION: The results show that chemotherapy combined with 7.5 Gy irradiated halpotype lymphocyte infusion could improve the complete remission of refractory leukemia and decrease the complications caused by chemotherapy.

[Effect of activation of cellular immunity on p58+ cells expressing killer-cell-inhibitory receptor cells].

UNLABELLED: The purpose of this study was to evaluate the effects of cellular immunity activation on P58(+) cells expressing killer cell inhibitory receptor (KIR) and their regulatory function on cellular immunity, and provid theoretical data for preventing graft-vers-host disease (GVHD) in stem cell transplantation therapy. The mononuclear cells from human peripheral blood were incubated with IL-2, Con A and Lipostin (LP) for 72 hours. The KIR expressing cells, P58.1(+) and P58.2(+) cells, were analyzed by flow cytometry. The results showed that the percentages of CD3(+), CD4(+), CD8(+), CD16(+)CD56(+), P58.1(+) and P58.2(+) cells were greatly increased after treated with IL-2, Con A and LP, separately or in combination, and the percentages of above cells in combined treatment groups were higher than those of single stimulated groups, especially the percentage of cells in the IL-2 + LP group was significantly higher than those in IL-2 and LP singly treated groups. IN CONCLUSION: IL-2, Con A and LP possess the ability to induce the expression of KIR and stimulate proliferation of P58.1(+) and P58.2(+) cells while to activate the celluar immunity response, the expression of P58 gene may be regulated by the activation of cellular immunity.

In vitro culture of human bone marrow mesenchymal stem cell clonies and induced differentiation into neuron-like cells.

OBJECTIVE: To study the long-term in vitro culture of human bone marrow mesenchymal stem cells (hMSC) and their phenotypical and functional properties. METHODS: Adherent hMSC colonies were digested by 0.25% trypsin-EDTA with a clone cycle for in vitro subculture. Flow cytometry was employed to examine the phenotypes of the cells. Their committed differentiation potential to neurons, clone-forming ability and growth curves were all investigated. RESULTS: hMSCs could be subcultured under this culture condition for 20 passages, expressing CD13, CD29 and CD59 but not CD11, CD14, CD31, CD34, CD45, CD80, CD86, CD117 and HLA-DR. The cells could be induced to differentiate into neurons when subcultured for 17 passages. CONCLUSION: hMSCs can be efficiently expanded under this culture condition, and the colony-derived hMSCs can maintain the differentiation potentials and retain their biological characteristics.

[Association of platelet endothelial cell adhesion molecule-1 gene polymorphism with coronary heart disease].

OBJECTIVE: To investigate the association of Leu125Val and Ser563Asn polymorphism of the gene encoding platelet endothelial cell adhesion molecule-1(PECAM-1) with coronary heart disease. METHODS: This study included 156 patients with the diagnoses of coronary heart disease (CHD) and coronary lesions derived from electrocardiography, myocardial enzyme analysis and coronary angiography as the CHD group, and another 75 in-patients admitted within the same period who showed no signs of CHD in the above examinations constituted the control group. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was employed to examine the missense polymorphism of PECAM-1gene in the position of Leu125Val and Ser563Asn. RESULTS: There were significant differences between CHD and control group in terms of the allele frequencies and genotype distributions of PECAM-1 gene, and the differences were especially conspicuous in the allele frequencies of 125Val and 563Asn (P<0.05) and genotype distributions of 125Val/Val and 563Asn/Asn. CONCLUSION: PECAM-1 gene polymorphism 1 may be a genetic risk factor for coronary heart disease.

[Modulation of the rate of CD158a+/b+ cells by Th1-and Th2-like cytokines].

AIM: To explore modulation of CD158+ cells in human peripheral blood by Th1-and Th2-like cytokines and provide basic data for inducing immune tolerance and preventing graft-versus-host disease (GVHD) in stem cells transplantation. METHODS: Peripheral blood mononuclear from healthy adults were cultured with Th1-like cytokines IL-2, IFN-gamma and Th2-like cytokines IL-4, IL-6 for 72 hours, rates of CD3+, CD4+, CD8+ cells, CD16+ CD56+ cells and CD158a+/b+ cells were analyzed by FACS. RESULTS: (1) The effects of cytokines on CD3+, CD4+, CD8+ and CD16+ CD56+ cells: the rates of above cells were greatly increased after being treated with IL-2 or IFN-gamma(P< 0.05), but efficacy of IL-2 was higher than that of IFN-gamma(P< 0.05). The rates of above cells in IL-2+IFN-gamma treated cells were higher than that in IL-2 or IFN-gamma treated alone. The rates of above cells were greatly decreased after being treated with IL-4+IL-6(P< 0.05), but efficacy of combination of IL-2+IL-4 was higher than that of IL-4 alone, lower than that of IL-2 alone (P< 0.05). (2) The effects of cytokines on CD158a+/b+ cells: the rates of CD158a+/b+ cells in total mononuclear and in CD3+, CD4+, CD8+ and CD16+ CD56+ cells were significantly raised after being treated with IL-2 (P< 0.01), but had no significance changes after being treated with IFN-gamma. The rates of CD158a+/b+ cells were decreased after being treated with IL-4+IL-6, whereas increased after being treated with IL-2+IFN-gamma(P< 0.05), but efficacy of being treated with IL-2+IL-4 was lower than that with IL-2(P< 0.05). CONCLUSION: IL-2 plays an important role in the regulation of CD158a/b expression or proliferation of CD158a+/b+ cells. It may involve in controlling NK cells and T cells activity via expression of regulating these molecules or stimulating proliferating of CD158a+/b+ cells. IL-4 and IL-6 have a slight ability to decrease the rates of CD158a+/b+ cells and IL-4 can partially reverse the effect of IL-2 on CD158a+/b+ cells.

[Construction of MHC I gene retroviral expression vector and its expression in hematopoietic cells].

OBJECTIVE: To construct the retroviral expression vector of BALB/c mouse H-2Dd gene and study its expression in C57BL/6 mouse hematopoietic cells (MHC). METHODS: A retroviral vector pMSCV encoding H-2Dd gene was transduced into the packaging cell line PT67 by lipofectin, and the hematopoietic cells of C57BL/6(H-2Dd negative) were infected by the above viral supernatant. Reverse transcriptase-polymerase chain reaction and flow cytometry were employed to examine the expression of H-2Dd on the infected cells. RESULTS: The cDNA encoding H-2Dd was correctly inserted into the vector pMSCV, as confirmed by restriction endonuclease digestion. The H-2Dd gene was integrated into the C57BL/6 mouse hematopoietic cell genome and expressed on the cell surface. CONCLUSION: Recombinant H-2Dd of BALB/c mouse retroviral expression vector has been successfully constructed and its expression obtained in C57BL/6 mouse hematopoietic cells, which may facilitate further study of the function of MHC in transplantation immunology.