Dendritic cells(DCs) are professinal antigen-presenting cells with the ability to initiate primary Tcell responses. While it iswell known that inflammatory stimuli induce the functional maturation of immature DCs, whe...Dendritic cells(DCs) are professinal antigen-presenting cells with the ability to initiate primary Tcell responses. While it iswell known that inflammatory stimuli induce the functional maturation of immature DCs, whether adhesion molecule selectins regulate DCmaturation is poorly understood. Using anti-P-selectin lectin-EGF domain monoclonal antibody (PsL-EGFmAb) that blocks the adhesionof P-, E-, and L-selectin, we demonstrate herein that selectins play important role in stimulating functional maturation of immature DCs.Immature DCs are generated from human cord blood CD34+hematopoietic stem/progenitor cells that were cultured in the presence of stemcell factor, Fms-like tyrosine-kinase-3 ligand, granulocyte-macrophage colony stimulating factor, and transform growth factor-β1. Whenstimulated with tumor necrosis factor-alpha(TNF-α), immature DCs differentiated into mature DCs, producing increased levels of costim-ulatory molecules and interleukin (IL)-12 and obtaining the ability to potently activate naive Tcells. Interestingly, in contrast to matureDCs derived from TNF-α-induced immature DC cultures without PsL-EGFmAb, immature DCs treated with PsL-EGFmAb for7 days werecompletely blocked their maturation, as evidenced by decreased expression of costimulatory molecules CD80, CD86, and CD83, inhibi-ted production of IL-12, and inability to activate naive Tcellsin vitro. Thus, blockade of selectins using PsL-EGFmAb will prove to bea valuable tool for the study of the molecuar mechanisms of DC maturation, as well as for the prevention and treatment of DC-mediated au-toimmunity.展开更多
Anti-HER2 monoclonal antibody （Sc7301）-paclitaxel （TAX） immunoconjugate was pre- pared and its specific binding to tumor cells was investigated in this study. Sc7301 was conjugated to TAX by the active ester metho...Anti-HER2 monoclonal antibody （Sc7301）-paclitaxel （TAX） immunoconjugate was pre- pared and its specific binding to tumor cells was investigated in this study. Sc7301 was conjugated to TAX by the active ester method and then the TAX-Sc7301 immunoconjugate was obtained. After purification and labeling by Cyano-fluorescein isothiocyanate （FITC）, the specific binding of TAX-Sc7301 to HER2-positive tumor cells （SKOV3） and HER2-negative tumor cells （HepG2） was evaluated respectively. TAX-Sc7301 （20 nmol/L） showed distinct specific binding to SKOV3 cells rather than HepG2 cells. And the uptake of the immunoconjugate by SKOV3 cells was increased with the TAX-So7301 concentration （3-48 nmol/L） and the incubation time （P〈0.05）. It was concluded that the TAX-Sc7301 immunoconjugate is ootentially applicable as a targeted agent against HER2-10ositive tumor cells.展开更多
A hybridoma cell line secreting monoclonal antibody to idiotope of the monoclonalantibody 94D1 specific for asexual erythrocytic stages of Plasmodium falciparum was established byfusion of SP2/0 mouse myeloma cells wi...A hybridoma cell line secreting monoclonal antibody to idiotope of the monoclonalantibody 94D1 specific for asexual erythrocytic stages of Plasmodium falciparum was established byfusion of SP2/0 mouse myeloma cells with spleen cells of Wistar rats immunized with monoclonalIgG of 94D1 purified from ascitic fluid of BALB/C mouse by affinity chromatography on ProteinA- Sepharose CL- 4B. Specificity of the anti - idiotope antibody (anti - Id), 41RF5, was deter-mined with indirect enzyme-linked immunosorbent assay (ELISA). The results showedthat 41RF5 reacted only with 94D1 IgG2b, not with normal mouse IgG and other seven mousemonoclonal antibodies - five specific for erythrocytic stages of P. falciparum, one for erythrocyticstages of P. inui, and one for Dengue fever virus type III, which indicates that 41RF5 does recognizespecifically the idiotope of 94D1 monoclonal antibody. In 41RF5 heterohybrid culture supernatant,anti-Id titre measured by ELISA was above 1:1 280. Up to the present, the heterohybrid cell linehas been cultured stably for 16 months.展开更多
Objective:To evaluate the immunosuppressive effect of monoclonal antibodies (McAb) against cell surface adhesion molecules on transplant rejection. Methods: C57BL/6 (H-2b) mouse cardiac grafts were transplanted into B...Objective:To evaluate the immunosuppressive effect of monoclonal antibodies (McAb) against cell surface adhesion molecules on transplant rejection. Methods: C57BL/6 (H-2b) mouse cardiac grafts were transplanted into BALB/c(H- 2d) mice. This model was used to investigate the possibility of immunosuppressive induction with CD44 McAb, leukocyte function associated antigen (LFA-1) and intercellular adhesion molecule (ICAM-1). Results: Treatment of the allograft recipients with CD44 McAb alone, or both LFA-1 and ICAM-1 or combination of these 3 McAb significantly prolonged the cardiac allografts survival as compared with PBS controls (P<0.01). The combination of anti-CD44 and ICAM-1 and LFA-1 McAb was shown to produce more significant prolongation of grafts survival than anti-CD44 McAb alone or both anti-ICAM- 1 and LFA-1 McAb (P < 0.01). Histological examination of the grafts treated with the McAb displayed greatly reduced mononuclear cell infiltration. The proliferation of spleen cells from recipient BALB/c with McAb treatment was significantly inhibited in response to the stimulators of C57BL/6 spleen cells, but increased upon the stimulation of C3H/He (H-2k) spleen cells, as demonstrated by mixed lymphocyte reaction. Similarly, the cytotoxic activity against donor H-2-compatible (H-2b) target cells, EL-4 cells, was significantly suppressed. The spleen cells from allografted recipient BALB/c mice with McAb treatment induced specific tolerance for C57BL/6 cardiac grafts in allografted recipients, whereas those from allografted BALB/c mice without McAb treatment induced acute rejection. Conclusion: These results indicate that antiadhesion therapy using a combination of McAb to adhesion molecules can induce specific immunosuppression of transplant rejection.展开更多
From the mouse hybridoma cell line secreting an anti-CD4 monoclonal antibody (McAb), total RNA was prepared. The VH and VL genes were amplified by RT-PCR with family specific primer pairs. The PCR products were cloned...From the mouse hybridoma cell line secreting an anti-CD4 monoclonal antibody (McAb), total RNA was prepared. The VH and VL genes were amplified by RT-PCR with family specific primer pairs. The PCR products were cloned into pGEM-T vectors, then tranfected into JM109. The VH and VL genes were snalyzed by automatic DNA sequencer. According to Kabat classification, the VH and VL genes belong to the mouse ig heavy subgroup Ⅱ(A) and x chain subgroupⅢ, respectively. The VH and VL genes were subcloned into pr1-Expr and Pk Expr respectively, then transfected into XL2-Blue. The VH- Pr1 and VL- pk were trans feeted by electroporation into mouse myeloma cell X63Ag8. 653. The transfectoma cells were selected by G418 screening, and then supernatant of cultured transfectoma were analyzed by ELISA and immunofluorescence techniques.We have acquired transfectoma cells secreting anti-CD4 chimeric antibodies.These chimeric antibodies are able to kill tumor cells specifically in vitro.展开更多
文摘Dendritic cells(DCs) are professinal antigen-presenting cells with the ability to initiate primary Tcell responses. While it iswell known that inflammatory stimuli induce the functional maturation of immature DCs, whether adhesion molecule selectins regulate DCmaturation is poorly understood. Using anti-P-selectin lectin-EGF domain monoclonal antibody (PsL-EGFmAb) that blocks the adhesionof P-, E-, and L-selectin, we demonstrate herein that selectins play important role in stimulating functional maturation of immature DCs.Immature DCs are generated from human cord blood CD34+hematopoietic stem/progenitor cells that were cultured in the presence of stemcell factor, Fms-like tyrosine-kinase-3 ligand, granulocyte-macrophage colony stimulating factor, and transform growth factor-β1. Whenstimulated with tumor necrosis factor-alpha(TNF-α), immature DCs differentiated into mature DCs, producing increased levels of costim-ulatory molecules and interleukin (IL)-12 and obtaining the ability to potently activate naive Tcells. Interestingly, in contrast to matureDCs derived from TNF-α-induced immature DC cultures without PsL-EGFmAb, immature DCs treated with PsL-EGFmAb for7 days werecompletely blocked their maturation, as evidenced by decreased expression of costimulatory molecules CD80, CD86, and CD83, inhibi-ted production of IL-12, and inability to activate naive Tcellsin vitro. Thus, blockade of selectins using PsL-EGFmAb will prove to bea valuable tool for the study of the molecuar mechanisms of DC maturation, as well as for the prevention and treatment of DC-mediated au-toimmunity.
基金supported by a grant from the National Natural Science Foundation of China(No.30300429)
文摘Anti-HER2 monoclonal antibody （Sc7301）-paclitaxel （TAX） immunoconjugate was pre- pared and its specific binding to tumor cells was investigated in this study. Sc7301 was conjugated to TAX by the active ester method and then the TAX-Sc7301 immunoconjugate was obtained. After purification and labeling by Cyano-fluorescein isothiocyanate （FITC）, the specific binding of TAX-Sc7301 to HER2-positive tumor cells （SKOV3） and HER2-negative tumor cells （HepG2） was evaluated respectively. TAX-Sc7301 （20 nmol/L） showed distinct specific binding to SKOV3 cells rather than HepG2 cells. And the uptake of the immunoconjugate by SKOV3 cells was increased with the TAX-So7301 concentration （3-48 nmol/L） and the incubation time （P〈0.05）. It was concluded that the TAX-Sc7301 immunoconjugate is ootentially applicable as a targeted agent against HER2-10ositive tumor cells.
文摘A hybridoma cell line secreting monoclonal antibody to idiotope of the monoclonalantibody 94D1 specific for asexual erythrocytic stages of Plasmodium falciparum was established byfusion of SP2/0 mouse myeloma cells with spleen cells of Wistar rats immunized with monoclonalIgG of 94D1 purified from ascitic fluid of BALB/C mouse by affinity chromatography on ProteinA- Sepharose CL- 4B. Specificity of the anti - idiotope antibody (anti - Id), 41RF5, was deter-mined with indirect enzyme-linked immunosorbent assay (ELISA). The results showedthat 41RF5 reacted only with 94D1 IgG2b, not with normal mouse IgG and other seven mousemonoclonal antibodies - five specific for erythrocytic stages of P. falciparum, one for erythrocyticstages of P. inui, and one for Dengue fever virus type III, which indicates that 41RF5 does recognizespecifically the idiotope of 94D1 monoclonal antibody. In 41RF5 heterohybrid culture supernatant,anti-Id titre measured by ELISA was above 1:1 280. Up to the present, the heterohybrid cell linehas been cultured stably for 16 months.
文摘Objective:To evaluate the immunosuppressive effect of monoclonal antibodies (McAb) against cell surface adhesion molecules on transplant rejection. Methods: C57BL/6 (H-2b) mouse cardiac grafts were transplanted into BALB/c(H- 2d) mice. This model was used to investigate the possibility of immunosuppressive induction with CD44 McAb, leukocyte function associated antigen (LFA-1) and intercellular adhesion molecule (ICAM-1). Results: Treatment of the allograft recipients with CD44 McAb alone, or both LFA-1 and ICAM-1 or combination of these 3 McAb significantly prolonged the cardiac allografts survival as compared with PBS controls (P<0.01). The combination of anti-CD44 and ICAM-1 and LFA-1 McAb was shown to produce more significant prolongation of grafts survival than anti-CD44 McAb alone or both anti-ICAM- 1 and LFA-1 McAb (P < 0.01). Histological examination of the grafts treated with the McAb displayed greatly reduced mononuclear cell infiltration. The proliferation of spleen cells from recipient BALB/c with McAb treatment was significantly inhibited in response to the stimulators of C57BL/6 spleen cells, but increased upon the stimulation of C3H/He (H-2k) spleen cells, as demonstrated by mixed lymphocyte reaction. Similarly, the cytotoxic activity against donor H-2-compatible (H-2b) target cells, EL-4 cells, was significantly suppressed. The spleen cells from allografted recipient BALB/c mice with McAb treatment induced specific tolerance for C57BL/6 cardiac grafts in allografted recipients, whereas those from allografted BALB/c mice without McAb treatment induced acute rejection. Conclusion: These results indicate that antiadhesion therapy using a combination of McAb to adhesion molecules can induce specific immunosuppression of transplant rejection.
文摘From the mouse hybridoma cell line secreting an anti-CD4 monoclonal antibody (McAb), total RNA was prepared. The VH and VL genes were amplified by RT-PCR with family specific primer pairs. The PCR products were cloned into pGEM-T vectors, then tranfected into JM109. The VH and VL genes were snalyzed by automatic DNA sequencer. According to Kabat classification, the VH and VL genes belong to the mouse ig heavy subgroup Ⅱ(A) and x chain subgroupⅢ, respectively. The VH and VL genes were subcloned into pr1-Expr and Pk Expr respectively, then transfected into XL2-Blue. The VH- Pr1 and VL- pk were trans feeted by electroporation into mouse myeloma cell X63Ag8. 653. The transfectoma cells were selected by G418 screening, and then supernatant of cultured transfectoma were analyzed by ELISA and immunofluorescence techniques.We have acquired transfectoma cells secreting anti-CD4 chimeric antibodies.These chimeric antibodies are able to kill tumor cells specifically in vitro.
