In vitro study of the influence of GST-π gene transfer on drug-resistance of human cord blood CD34^+ cells

Objective:To investigate the influence of GST-π gene transfer on drug-resistance of human cord blood CD34 + cells.Methods:CD34 + cells were purified from cord blood from normal full-term pregnancy.Gene transduction into human cord blood CD34 + cells was carried out using GST-π gene containing retrovirus vector.The GST-π gene expression in transduced CD34 + cell was confirmed by RT-PCR.After confirmation of GST-π gene transfer,the transfected CD34 + cells were cultured by colony assay in the presence of carboplatin.Results:GST-π mRNA was detected in 30% of CFU-GM derived from GST-π gene transduced CD34 + cells.In vitro drug resistance test showed that the number of CFU-GM formed was significantly higher (2～3 fold) in GST-π gene transduced CD34 + cells than untransduced CD34 +cells.Conclusion:GST-π gene transfer can confer resistance to hematopoietic progenitors against carboplatin in vitro.

The invivo study of myeloprotection by GST-π gene transfected human cord blood hematopoietic stem cells transplantation

Objective :To investigate the influence of GST πgenetransferintohumancord blood hematopoie ticstem cellson their drugres is tanceagains tanti tumordrugs invivo .Methods: GST πgenetran sfectionin to human cord blood CD 34+cells was carried outusing are trovirusvec torPLJ GST πwith the aido f fibronect in .Succes sfulgenetransfer was confirmed by invitrocolony assay and RT PCR .GST πgenetrans duced human cord blood CD34+cells were the nengrafted in to 4 week old total body irradiated NOD/Scid mice and carboplatin was intraperitoneally admin is tered sequentially at 4 weeks interval 4 week saftereng raftment.Results :Peripheral blood (PB) WBC was significantly higher in GST πmice than control mice after 2 course of car boplat in .Retroviral GST π expression in bone marrow hematopoietic progenitor cells of recipient mice was detected by RT PCR 16 weeks after Xenotransplantation .Conclusion :The transfection of GST π gene could confer ,to some extent ,resistance to cord blood stem cells against carboplatin in vivo .

The effect of interleukin-6 gene transfer on human cord blood megaka ryopoiesis

Objective:To investigate the effect of IL-6 gene transfe r into human cord blood hematopoietic stem cells on the production of megakaryocy t ic progenitors.Methods:IL-6 gene was transfected into human c o rd blood CD34+ cells using a retrovirus vector with the aid of recombinant fibro nectin fragments in the presence of a cocktail of cytokines (SCF,IL-6,sIL-6R,F L,and TPO).Colony-forming units-megakaryocyte (CFU-MK) assays were performed as IL-6 gene transduced CD34+ cells were incubated alone or in combination with I L -3 or sIL-6R, controlled with neoR gene transduced CD34+ cells.Result s :IL-6 alone or sIL-6R alone stimulated few CFU-MK colonies,the addit ion of sIL-6R to IL-6 gene transduced CD34+ cells significantly enhanced the prod uction of CFU-MK colonies.IL-6 gene transduced CD34+ cells showed a modest syn er gistic effect with IL-3.Conclusion:These results suggest that IL-6 gene transfer may protect patients from chemotherapy-induced thrombocytop en ia.

Study of cellular immunity response of mB7-1 gene transfected mouse ovarian cancer cell line and its tumorigenecities in vivo

Objective:To investigate the cellular immunity response in vitro and the tumorigenecities in vivo of mB7 1 gene transfected murine ovarian cancer cell line.Methods:mB7 1 gene was transfected into the NuTu 19 cell line by retrovirus vector, and the expression of mB7 1 gene was confirmed by flow cytometry(FCM).NuTu 19/neo and NuTu 19/mB7 1 cells were injected subcutaneously into syngeneic Fischer 344 rats respectively,and their tumorigenecities were recorded.Proliferation indices of lymphocyte were assayed after syngenieic mixed tumor lymphocyte cultures(MTLCs).The lysis activity of CTL toward tumor cells was determined using methyl thiazolyl tetrazolium(MTT) assay.Results:Successful transfection of mB7 1 gene into NuTu 19 cell line was comfirmed with FCM.In vitro study showed that there was no obvious changes in cell growth of gene transfected cell line,compared with the cell line NuTu 19.NuTu 19/mB7 1 cells could induce more effective proliferation of effector lymphocytes(P<0.05). The lysis activity of CTL activated by NuTu 19/mB7 1 was stronger than that of NuTu 19/neo (P<0.01).Tumor sizes were smaller in the NuTu 19/mB7 1 receptance syngeneic Fischer 344 rats compared with those in the control group.Conclusion:mB7 1 genetically modified ovarian cancer cells could induce the cellular immunity response in vitro and the tumorigenecitiy of NuTu 19 cells was decreased after inoculation with the experimental vaccine.