AIM: Allo-cell transplant rejection and autoimmune responses were associated with the presence of class Ⅱmajor histocompatibility complex (MHC Ⅱ) molecules on cells.This paper studied the effect of Ribonuclease P (R...AIM: Allo-cell transplant rejection and autoimmune responses were associated with the presence of class Ⅱmajor histocompatibility complex (MHC Ⅱ) molecules on cells.This paper studied the effect of Ribonuclease P (RNase P)against CIITA, which was a major regulator of MHCII molecules, on repressing the expression of MHCII molecules on hepatocyte.METHODS: M1-RNA is the catalytic RNA subunit of RNase P from Escherichia coli. It were constructed that M1-RNA with guide sequences (GS) recognizing the 452, 3408 site of CIITA by PCR from pTK117 plasmid, then were cloned into the EcoRI/Bg/II or EcoR//SalIsite of vector psNAV (osNAV-M1-452-GS, psNAV-M1-3408-GS) respectively. The target mould plate (3176-3560) of CIITA was obtained from Raji cell by RT-PCR, and then inserted into the XhoI/EcoRIof pGEM-7zf(+) plasmid (pGEM-3176). These recombinant plasmids were screened out by sequence analysis. psNAV-M 1-452-GS, psNAV-M1-3408-GS and its target RNA pGEM-3176 were transcribed and then mixed up and incubated in vitro. It showed that M1-3408-GS could exclusively cleave target RNA that formed a base pair with the GS. Stable transfectants of hepatocyte cell line with psNAVl-M1-3408-GS were tested for expression of class Ⅱ MHC through FCM, for mRNA abundance of MHCII, Ii and CIITA by RTPCR., for the level of IL-2 mRNA on T cell by mixed lymphocyte reaction.RESULTS: When induced with recombinant human interferon-gamma (IFN-γ), the expression of HLA-DR, -DP,-DQ on psNAV-M1-3408-GS+ hepatocyte was reduced 83.27 %, 88.93 %, 58.82 % respectively, the mRNA contents of CIITA, HLA-DR, -DP, -DQ and Ii decreased significantly.While T cell expressed less IL-2 mRNA in the case of psNAV-M1-3408-GS+ hepatocyte.CONCLUSION: The Ribonuclease P against CIITA-M1-3408-GS could effectively induce antigen-specific tolerance through cleaving CIITA. These results provided insight into the future application of M1-3408-GS as a new nucleic acid drug against allo-transplantation rejection and autoimmune diseases.展开更多
A novel fluorene-based conjugated copolymer containing cyclobutenedione unit was synthesized by Suzuki reaction. Its structure and properties were characterized by FTIR, 1HNMR, elemental analysis, PL spectroscopy, DSC...A novel fluorene-based conjugated copolymer containing cyclobutenedione unit was synthesized by Suzuki reaction. Its structure and properties were characterized by FTIR, 1HNMR, elemental analysis, PL spectroscopy, DSC, TGA and cyclic voltammetry. The resulting polymer shows strong yellow PL emission (561 nm) and good solubility in polar aprotic solvents, i.e. THF, DMF, DMAC, DMSO, etc. DSC and TGA studies reveal that the novel polymer possesses excellent thermal stability with high glass transition temperature of 127℃ and onset decomposition temperature of 411℃. Cyclic voltammetry measurement demonstrated that the polymer has both hole and electron-transporting property.展开更多
基金the Science and Technology Development Foundation of Shanghai municipality,No.0143nm068the Great Branch Project of the Science and Technology Development Foundation of Shanghai Municipality,No.00DJ14001-8
文摘AIM: Allo-cell transplant rejection and autoimmune responses were associated with the presence of class Ⅱmajor histocompatibility complex (MHC Ⅱ) molecules on cells.This paper studied the effect of Ribonuclease P (RNase P)against CIITA, which was a major regulator of MHCII molecules, on repressing the expression of MHCII molecules on hepatocyte.METHODS: M1-RNA is the catalytic RNA subunit of RNase P from Escherichia coli. It were constructed that M1-RNA with guide sequences (GS) recognizing the 452, 3408 site of CIITA by PCR from pTK117 plasmid, then were cloned into the EcoRI/Bg/II or EcoR//SalIsite of vector psNAV (osNAV-M1-452-GS, psNAV-M1-3408-GS) respectively. The target mould plate (3176-3560) of CIITA was obtained from Raji cell by RT-PCR, and then inserted into the XhoI/EcoRIof pGEM-7zf(+) plasmid (pGEM-3176). These recombinant plasmids were screened out by sequence analysis. psNAV-M 1-452-GS, psNAV-M1-3408-GS and its target RNA pGEM-3176 were transcribed and then mixed up and incubated in vitro. It showed that M1-3408-GS could exclusively cleave target RNA that formed a base pair with the GS. Stable transfectants of hepatocyte cell line with psNAVl-M1-3408-GS were tested for expression of class Ⅱ MHC through FCM, for mRNA abundance of MHCII, Ii and CIITA by RTPCR., for the level of IL-2 mRNA on T cell by mixed lymphocyte reaction.RESULTS: When induced with recombinant human interferon-gamma (IFN-γ), the expression of HLA-DR, -DP,-DQ on psNAV-M1-3408-GS+ hepatocyte was reduced 83.27 %, 88.93 %, 58.82 % respectively, the mRNA contents of CIITA, HLA-DR, -DP, -DQ and Ii decreased significantly.While T cell expressed less IL-2 mRNA in the case of psNAV-M1-3408-GS+ hepatocyte.CONCLUSION: The Ribonuclease P against CIITA-M1-3408-GS could effectively induce antigen-specific tolerance through cleaving CIITA. These results provided insight into the future application of M1-3408-GS as a new nucleic acid drug against allo-transplantation rejection and autoimmune diseases.
文摘A novel fluorene-based conjugated copolymer containing cyclobutenedione unit was synthesized by Suzuki reaction. Its structure and properties were characterized by FTIR, 1HNMR, elemental analysis, PL spectroscopy, DSC, TGA and cyclic voltammetry. The resulting polymer shows strong yellow PL emission (561 nm) and good solubility in polar aprotic solvents, i.e. THF, DMF, DMAC, DMSO, etc. DSC and TGA studies reveal that the novel polymer possesses excellent thermal stability with high glass transition temperature of 127℃ and onset decomposition temperature of 411℃. Cyclic voltammetry measurement demonstrated that the polymer has both hole and electron-transporting property.
