Objective: The aim in this study was to identify the allelicfrequencies of the chemokine (SDF1-3'A) and chemokinereceptor (CCR5△32, CCR5m303 and CCR2-64I) genesresistant to HIV-1 infection and/or disease progress...Objective: The aim in this study was to identify the allelicfrequencies of the chemokine (SDF1-3'A) and chemokinereceptor (CCR5△32, CCR5m303 and CCR2-64I) genesresistant to HIV-1 infection and/or disease progression inindigenous Chinese populations. Methods: By using QIAamp DNA Blood Mini Kit, thegenomic DNA samples were purified from whole peripheralblood of healthy individuals (n=2067) from Han, Uygur,Mongolian and Tibetan ethnic groups, as well as Han patientsincluding HIV-1 carriers (n=330), patients with other sexuallytransmitted diseases (STDs, n=259) and intravenous drugusers (IVDUs, n=125). The allelic polymorphisms wereidentified by means of PCR or PCR-RFLP analyses. Thesequences of randomly selected amplified PCR products werefurther confirmed by direct DNA sequencing. Results: The mutant frequencies were identified to be0%～3.48% for CCR5△32, 0% for CCR5m303,19.15%～28.79% for CCR2-64 and 19.10%～28.73% for SDF1-3'A alleles, respectively, in Chinese healthy individuals fromfour ethnic groups. Our findings indicated the allelicfrequencies vary among the different ethnic groups.Furthermore, the HIV-1 carriers, STD cases and IVDUs (all ofHan ethnicity) were found to have the allelic frequencies of0%～0.19% (CCR5△32), 0% (CCR5m303), 19.31%～20.45%(CCR2-64) and 25.61%～26.83% (SDF1-3'A) with minorvariations in their frequencies between the patients andhealthy Han groups. There was no CCR5-m303 mutationfound in any subject in this study. Conclusion: The examined subjects of four Chinese ethnicorigins showed lower frequencies of CCR5△32 andCCR5m303 alleles, but higher frequencies of mutant CCR2-64I and SDF1-3'A alleles compared to those identified innorthern-European and American Caucasians. Thesignificance of the different frequencies and polymorphisms ofthe above alleles in Chinese populations needs to be furtherexamined in HIV-1/AIDS diseases.展开更多
To investigate the phenotypic knockout of HIV-1 chemokine coreceptor CXCR4 and CCR5 by intrakines and its inhibitory effect on HIV-1 infection. Primary human PBLs were transduced with the recombinant vector pLNCX-R-K-...To investigate the phenotypic knockout of HIV-1 chemokine coreceptor CXCR4 and CCR5 by intrakines and its inhibitory effect on HIV-1 infection. Primary human PBLs were transduced with the recombinant vector pLNCX-R-K-S-K followed by anti-NGFR/anti-IgG-magnetic bead method selection and FCM detection. The transduced PBI.S were infected with DP1 HFV-1 virus thereafter envelope-mediated syncytium formation and p24 detection were carried out to study the blockage of HIV-1 infection by co-inactivation of CCR5 and CXCR4. pLNCX-R-K-S-K -transduced PBLs were isolated with an anti-NGFR/anti-IgG-magnetic bead method. After isolation, about 70% of the PBI.S were posi- tive for the NGFR marker. When the transduced PBLs were infected with DP1 HIV-1 virus, envelop-mediated syncytium for- mation was almost completely inhibited by pLNCX-R-K-S-K transfection. Also, p24 antigen was very low in the cultures of pLNCX-R-K-S-K transduced PBLs. pLNCX-R-K-S-K transduction inhibited the produc- tion of DP1 p24 antigen by 15%, 43% and 19% on days 4, 7 and 10 respectively. The lymphocytes with the phenotypic knockout of CCR5 and CXCR4 could protect primary human PBLs from DP1 HIV-1 virus infection.展开更多
Epstein-Barr virus(EBV)-associated gastric cancer(EBVaGC)cells originate from a single-cell clone infected with EBV.However,more than 95%of patients with gastric cancer have a history of Helicobacter pylori(H.pylori)i...Epstein-Barr virus(EBV)-associated gastric cancer(EBVaGC)cells originate from a single-cell clone infected with EBV.However,more than 95%of patients with gastric cancer have a history of Helicobacter pylori(H.pylori)infection,and H.pylori is a major causative agent of gastric cancer.Therefore,it has long been argued that H.pylori infection may affect the development of EBVaGC,a subtype of gastric cancer.Atrophic gastrointestinal inflammation,a symptom of H.pylori infection,is observed in the gastric mucosa of EBVaGC.Therefore,it remains unclear whether H.pylori infection is a cofactor for gastric carcinogenesis caused by EBV infection or whether H.pylori and EBV infections act independently on gastric cancer formation.It has been reported that EBV infection assists in the oncogenesis of gastric cancer caused by H.pylori infection.In contrast,several studies have reported that H.pylori infection accelerates tumorigenesis initiated by EBV infection.By reviewing both clinical epidemiological and experimental data,we reorganized the role of H.pylori and EBV infections in gastric cancer formation.展开更多
To lay background for studying rejection mechanisms in xenotransplantation and developing the strategies for intervention, class I genes of swine leukocyte antigens (SLA) of three Chinese pig strains Bm, Gz and Yn wer...To lay background for studying rejection mechanisms in xenotransplantation and developing the strategies for intervention, class I genes of swine leukocyte antigens (SLA) of three Chinese pig strains Bm, Gz and Yn were cloned and sequenced. The cDNA of the class I loci P1 and P14 were amplified by RT-PCR and subjected to insert into sequencing vectors. All six allelic sequences we examined, each two for one Chinese strain, are not identical to those reported, which allows these novel sequences receiving their accession numbers AY102467- AY102472 from GenBank. This study further reveals that the homologies of MHC class I genes in their primary structures and the deduced amino acids between Chinese pigs (SLA) and human (HLA-A*0201) are better than those between pigs and mice (H-2Db/H-2Kb). The comparison also indicates that the amino acid residues critical for recognition by human KIRs are altered in the swine class I molecules. The amino acids responsible for binding human CD8 coreceptor are largely conserved although there are two critical residues substituted. A functional test indicated that the human T cells specific for the prokaryotically expressed SLA Plprotein could respond quite well in vitro to the class I-positive swine chon-drocytes and PBMCs in presence of human APCs. This implies that, due to the substitution of two critical residues, the inaccessibility of human CD8 coreceptor to swine class I molecule might be contributable to the indirect pathway that the human T cells have to use for recognizing the SLA class I xenogeneic antigens.展开更多
Objective Although HIV-1 infection is prevalent in many regions in China, it remains largely unknown on the biological characteristics of dominant circulating isolates. This study was designed to isolate the circulati...Objective Although HIV-1 infection is prevalent in many regions in China, it remains largely unknown on the biological characteristics of dominant circulating isolates. This study was designed to isolate the circulating viral strains from different prevalent regions and to characterize their biological properties and neutralization sensitivity. Methods Primary viruses were isolated from fresh PBMCs using the traditional co-culture method and their capacity of inducing syncytium was tested in MT-2 cells. Meanwhile, their coreceptor usage was determined with two cell lines: Magi and GHOST (3) stably expressing CD4 and the chemokine receptor CCR5 or CXCR4. Furthermore, the sensitivity of these viruses to neutralization by HIV-1-infected patients’ plasma which were highly active to neutralize SF33 strain, was quantified in GHOST cell-based neutralization assay. Results Six primary viral strains were isolated from 4 separated regions. Isolates LTG0213,LTG0214 and XVS032691 induced syncytia in MT-2 cells, and used CXCR4 as coreceptor. Isolates XJN0021, XJN0091, or SHXDC0041 did not induce syncytia, and used CCR5 as coreceptor. Overall neutralization sensitivity differed among four representative strains: HIV-1 XVS032691>LTG0214>XJN0091≈SHXDC0041. Conclusion The neutralization sensitivity of HIV isolates is linked with the phenotype of isolates, in which syncytium-inducing (SI) or CXCR4-tropic (X4) viruses are more easily neutralized than non-syncytium-inducing (NSI) or CCR5-tropic (R5) viruses. The genetic subtypes based on the phylogeny of env sequences are not classical neutralization serotypes.展开更多
CD8 engagement with class I major histocompatibility antigens greatly enhances T-cell activation, but it is not clear how this is achieved. We address the question of whether or not the antibody-mediated ligation of C...CD8 engagement with class I major histocompatibility antigens greatly enhances T-cell activation, but it is not clear how this is achieved. We address the question of whether or not the antibody-mediated ligation of CD8 alone induces transcriptional remodeling in a T-cell clone, using serial analysis of gene expression. Even though it fails to induce overt phenotypic changes, we find that CD8 ligation profoundly alters transcription in the T-cell clone, at a scale comparable to that induced by antibody-mediated ligation of CD3. The character of the resulting changes is distinct, however, with the net effect of CD8 ligation being substantially inhibitory. We speculate that ligating CD8 induces weak, T-cell receptor （TCR）-mediated inhibitory signals reminiscent of the effects of TCR antagonists. Our results imply that CD8 ligation alone is incapable of activating the T-cell clone because it fails to fully induce NFAT-dependent transcription.展开更多
Objective: To construct bicistronic expression vector with RANTES and SDF-1 genes, the ligands of HIV-1 principal coreceptors, and identify its expression. Methods: RANTES-KDEL was amplified from plasmid pCMV-R-K by P...Objective: To construct bicistronic expression vector with RANTES and SDF-1 genes, the ligands of HIV-1 principal coreceptors, and identify its expression. Methods: RANTES-KDEL was amplified from plasmid pCMV-R-K by PCR and cloned into eukaryotic expression vector pCMV-S/K. Gene transfection into HeLa cells was carried out by lipofectin. Indirect immumofluorescence and radioimmunoprecipitation were used to confirm the expression of RANTES and SDF-1. Results: The construction of pCMV-R-K-S-K was confirmed by enzymatic digestion and sequencing. RANTES and SDF-1 were shown expressed in HeLa cells by indirect immumofluorescence and radioimmunoprecipitation. Conclusion: pCMV-R-K-S-K was constructed and expressed in cell line Hela successfully, which will contribute to further study of gene therapy of AIDS by HIV-1 coreceptors knockout.展开更多
HIV-1 infection requires the expression of CD4＋ molecules in colligation with C-C chemokine receptor type 5 （CCR5） and C-X-C chemokine receptor type 4 （CXCR4） as the major coreceptors. The role of SNP in 3＇ untr...HIV-1 infection requires the expression of CD4＋ molecules in colligation with C-C chemokine receptor type 5 （CCR5） and C-X-C chemokine receptor type 4 （CXCR4） as the major coreceptors. The role of SNP in 3＇ untranslated region ofSDF-1 （SDF1-3 ＇A） and low copy number （CN） of the CCL3L1 gene is reported to confer increased resistance to HIV-1 infection. The aim of the present study was to analyze the combinatorial effect of both the variations in protection towards HIV-1 infection in Indian population. The combinatorial effect of genetic variation in terms of SNP in SDF-1 gene and CCL3L1 CN was investigated in 105 healthy individuals and 78 HIV-I patients. Genotyping of SDF-1 was performed by RFLP-PCR and CCL3L1 by real-time PCR using TaqMan chemistry. The genotype frequency distribution of SDF-1 was found to be （SDF-1/SDF-I： 65.4%, SDF-1/SDF1-3＇A： 29.5% and SDFI-3＇A/SDF1-3＇A- 5.1%） in HIV patients as compared to （SDF-1/SDF-I： 64.8%, SDF-1/SDF1-3＇A： 30.5% and SDF1-3 ＇A/SDF1-3 ＇A： 4.7%） in healthy individuals, whereas a range of 1 to 6 copies per diploid genome was observed for CCL3L1 gene.展开更多
Objective: Allelic polymorphisms of CCR5△32CCR2b-64I,CX3CR1-2491280M and SDF1-3'A associatedwith HIV-1 infection and disease progression wereinvestigated in indigenous Uygur populations from theXinjiang Uygur Aut...Objective: Allelic polymorphisms of CCR5△32CCR2b-64I,CX3CR1-2491280M and SDF1-3'A associatedwith HIV-1 infection and disease progression wereinvestigated in indigenous Uygur populations from theXinjiang Uygur Autonomous Region of China. Methods: The study population comprised 316 healthyUygur subjects with an age range of 1-80 years old, fromwhom whole peripheral blood samples were collected andnone were HIV-1 seropositive. Genomic DNA samples werepurified using a Qiagen Blood Kit. Genotyping of theaforementioned four alleles was performed using PCR orPCR/RFLP assay, and further confirmed by direct DNAsequencing. Results: The allelic frequencies in Chinese Uygurpopulation were as follows: 3.48% for CCR5△32; 19.45% forCCR2b-64I; 13.8% for CX3CR1-2491280M haplotype, and20.41% for SDF1-3'A. Mutant allele distributions amongUygur populations were in accordance with theHardy-Weinberg equilibrium. No statistical difference wasfound between the frequency of the three HIV coreceptors andtheir respective ligand genes. Conclusion: The frequency of SDF1-3'A andCX3CR1-2491280M haplotypes in these Uygur populationswas similar to that of Caucasian people, while the frequency ofthe CCR2b-64I haplotype more closely matched the HanChinese. The frequency of CCR5△A32 in Uygur populationswas between Caucasian and Hall frequencies, the more closelymatching the frequency in Medi-Asia people. No geneticlinkage between any two of the three HIV coreceptor geneswas found, but obvious genetic linkages existed betweenCX3CR1-249I and CX3CR1-280M,with even higher linkagedegrees than Caucasian people.展开更多
Limited genetic information is available concerning the polymorphisms of HIV-1 resistant genes in indigenous Chinese populations. The aim of this study is to identify the allelic frequencies of the chemokine and chemo...Limited genetic information is available concerning the polymorphisms of HIV-1 resistant genes in indigenous Chinese populations. The aim of this study is to identify the allelic frequencies of the chemokine and chemokine receptor genes in the Chinese mainland. Genomic DNA samples extracted from whole blood of 2318 subjects were analyzed by using PCR or PCR/restriction fragment length polymorphism (RFLP) assays, and further confirmed by direct DNA sequencing. Higher frequencies of mutant CCR2-64I (19.15%-28.79%) and SDF1-3’A (19.10% -29.86%) alleles were found in subjects of 8 ethnic groups in the Chinese mainland. In contrast, the △32 mutation in CCRS gene occurs at a very low frequency (0.0016, n=1287) in Han population. A relatively high frequency of CCR5-wt/△32 heterozygotes was observed in Uygurian and Mongolian populations. No A32 mutation allele was detected in Tibetan and other 4 ethnic groups in Yunnan Province. There was no CCR5-m303 mutation in subjects of any ethnic group in the Chinese展开更多
The chemokine receptors CCR5 and CXCR4 play an important role as coreceptors for human immunodeficiency virus type 1 （HIV-1） entring into cells. HIV-1 isolates can be distinguished by the chemokine coreceptors. Nons...The chemokine receptors CCR5 and CXCR4 play an important role as coreceptors for human immunodeficiency virus type 1 （HIV-1） entring into cells. HIV-1 isolates can be distinguished by the chemokine coreceptors. Nonsyncytium inducing （NSI）, macrophage tropic viruses utilizing CCR5, are called R5 viruses; syncytium inducing （SI） isolates use CXCR4 and known as X4 viruses. R5 viruses generally are associated with latent stage of infection and X4 viruses with later,展开更多
To elucidate the structures of SLA-DR(swine leukocyte antigen DR)genes of three Chinese pig strains (Gz,Bm and Yn),the SLA-DRA and SLA-DRB cDNA were amplified by RT-PCR and subjected to determine the sequences.The who...To elucidate the structures of SLA-DR(swine leukocyte antigen DR)genes of three Chinese pig strains (Gz,Bm and Yn),the SLA-DRA and SLA-DRB cDNA were amplified by RT-PCR and subjected to determine the sequences.The whole structures of SLA-DRA alleles are identical among three strains,consisting of 759 nucleotides including an open reading frame(ORF),and are shared with those reported from NIH minipigs SLA-DRA^c and SLA-DRA^d.The same length of the ORF-containing SLA-DRB genes of three Chinese pig strains was also identified.They are composed of 801 nucleotides encoding a xenogeneic antigen molecule of 266 amino acid residues.The nucleotide sequences of the SLA-DRB genes,however,are different when compared either among the three strains or with the published data of SLA-DRB sequences,which allowed our novel SLA-DRB alleles receiving their accession numbers AY102479,AY102480 and AY102481 from the GenBank.This study further reveals that the phylogenic homologies of MHC DR or DR-like genes in structures of nucleotides and deduced amino acids between Chinese pigs(SLA)and human(HLA-DRB1*0901)are better than those between pigs and mice (H-2~b Eβ).High similarities were also found for DRα-DRβ heterodimers between Chinese pigs and human in terms of amino acids sequences critical for binding with human CD4 coreceptor molecule,which are better than those between SLA-DR and H-2 I-E molecules.A functional test indicated that,by cotransfection with Bm-DRA and Bm-DRB genes,the Bm-DR molecule-expressed L929 cells could stimulate human T cells quite well in a xenogeneic reaction in presence of human APCs.Cellular & Molecular Immunology.2004;1 (3):212-218.展开更多
基金This project was supported by grant from National Natural Sciences Foundation of the PR China(39770683)
文摘Objective: The aim in this study was to identify the allelicfrequencies of the chemokine (SDF1-3'A) and chemokinereceptor (CCR5△32, CCR5m303 and CCR2-64I) genesresistant to HIV-1 infection and/or disease progression inindigenous Chinese populations. Methods: By using QIAamp DNA Blood Mini Kit, thegenomic DNA samples were purified from whole peripheralblood of healthy individuals (n=2067) from Han, Uygur,Mongolian and Tibetan ethnic groups, as well as Han patientsincluding HIV-1 carriers (n=330), patients with other sexuallytransmitted diseases (STDs, n=259) and intravenous drugusers (IVDUs, n=125). The allelic polymorphisms wereidentified by means of PCR or PCR-RFLP analyses. Thesequences of randomly selected amplified PCR products werefurther confirmed by direct DNA sequencing. Results: The mutant frequencies were identified to be0%～3.48% for CCR5△32, 0% for CCR5m303,19.15%～28.79% for CCR2-64 and 19.10%～28.73% for SDF1-3'A alleles, respectively, in Chinese healthy individuals fromfour ethnic groups. Our findings indicated the allelicfrequencies vary among the different ethnic groups.Furthermore, the HIV-1 carriers, STD cases and IVDUs (all ofHan ethnicity) were found to have the allelic frequencies of0%～0.19% (CCR5△32), 0% (CCR5m303), 19.31%～20.45%(CCR2-64) and 25.61%～26.83% (SDF1-3'A) with minorvariations in their frequencies between the patients andhealthy Han groups. There was no CCR5-m303 mutationfound in any subject in this study. Conclusion: The examined subjects of four Chinese ethnicorigins showed lower frequencies of CCR5△32 andCCR5m303 alleles, but higher frequencies of mutant CCR2-64I and SDF1-3'A alleles compared to those identified innorthern-European and American Caucasians. Thesignificance of the different frequencies and polymorphisms ofthe above alleles in Chinese populations needs to be furtherexamined in HIV-1/AIDS diseases.
文摘To investigate the phenotypic knockout of HIV-1 chemokine coreceptor CXCR4 and CCR5 by intrakines and its inhibitory effect on HIV-1 infection. Primary human PBLs were transduced with the recombinant vector pLNCX-R-K-S-K followed by anti-NGFR/anti-IgG-magnetic bead method selection and FCM detection. The transduced PBI.S were infected with DP1 HFV-1 virus thereafter envelope-mediated syncytium formation and p24 detection were carried out to study the blockage of HIV-1 infection by co-inactivation of CCR5 and CXCR4. pLNCX-R-K-S-K -transduced PBLs were isolated with an anti-NGFR/anti-IgG-magnetic bead method. After isolation, about 70% of the PBI.S were posi- tive for the NGFR marker. When the transduced PBLs were infected with DP1 HIV-1 virus, envelop-mediated syncytium for- mation was almost completely inhibited by pLNCX-R-K-S-K transfection. Also, p24 antigen was very low in the cultures of pLNCX-R-K-S-K transduced PBLs. pLNCX-R-K-S-K transduction inhibited the produc- tion of DP1 p24 antigen by 15%, 43% and 19% on days 4, 7 and 10 respectively. The lymphocytes with the phenotypic knockout of CCR5 and CXCR4 could protect primary human PBLs from DP1 HIV-1 virus infection.
基金Supported by Grant-in-Aid for Scientific Research From the Ministry of Education,Culture,Science and Technology of Japan,No.21K07054(Hironori Yoshiyama)and No.22K07101(Hisashi Iizasa).
文摘Epstein-Barr virus(EBV)-associated gastric cancer(EBVaGC)cells originate from a single-cell clone infected with EBV.However,more than 95%of patients with gastric cancer have a history of Helicobacter pylori(H.pylori)infection,and H.pylori is a major causative agent of gastric cancer.Therefore,it has long been argued that H.pylori infection may affect the development of EBVaGC,a subtype of gastric cancer.Atrophic gastrointestinal inflammation,a symptom of H.pylori infection,is observed in the gastric mucosa of EBVaGC.Therefore,it remains unclear whether H.pylori infection is a cofactor for gastric carcinogenesis caused by EBV infection or whether H.pylori and EBV infections act independently on gastric cancer formation.It has been reported that EBV infection assists in the oncogenesis of gastric cancer caused by H.pylori infection.In contrast,several studies have reported that H.pylori infection accelerates tumorigenesis initiated by EBV infection.By reviewing both clinical epidemiological and experimental data,we reorganized the role of H.pylori and EBV infections in gastric cancer formation.
基金supported by the grants from National Natural Science Foundation of China(No.39993430-2,30000157)
文摘To lay background for studying rejection mechanisms in xenotransplantation and developing the strategies for intervention, class I genes of swine leukocyte antigens (SLA) of three Chinese pig strains Bm, Gz and Yn were cloned and sequenced. The cDNA of the class I loci P1 and P14 were amplified by RT-PCR and subjected to insert into sequencing vectors. All six allelic sequences we examined, each two for one Chinese strain, are not identical to those reported, which allows these novel sequences receiving their accession numbers AY102467- AY102472 from GenBank. This study further reveals that the homologies of MHC class I genes in their primary structures and the deduced amino acids between Chinese pigs (SLA) and human (HLA-A*0201) are better than those between pigs and mice (H-2Db/H-2Kb). The comparison also indicates that the amino acid residues critical for recognition by human KIRs are altered in the swine class I molecules. The amino acids responsible for binding human CD8 coreceptor are largely conserved although there are two critical residues substituted. A functional test indicated that the human T cells specific for the prokaryotically expressed SLA Plprotein could respond quite well in vitro to the class I-positive swine chon-drocytes and PBMCs in presence of human APCs. This implies that, due to the substitution of two critical residues, the inaccessibility of human CD8 coreceptor to swine class I molecule might be contributable to the indirect pathway that the human T cells have to use for recognizing the SLA class I xenogeneic antigens.
文摘Objective Although HIV-1 infection is prevalent in many regions in China, it remains largely unknown on the biological characteristics of dominant circulating isolates. This study was designed to isolate the circulating viral strains from different prevalent regions and to characterize their biological properties and neutralization sensitivity. Methods Primary viruses were isolated from fresh PBMCs using the traditional co-culture method and their capacity of inducing syncytium was tested in MT-2 cells. Meanwhile, their coreceptor usage was determined with two cell lines: Magi and GHOST (3) stably expressing CD4 and the chemokine receptor CCR5 or CXCR4. Furthermore, the sensitivity of these viruses to neutralization by HIV-1-infected patients’ plasma which were highly active to neutralize SF33 strain, was quantified in GHOST cell-based neutralization assay. Results Six primary viral strains were isolated from 4 separated regions. Isolates LTG0213,LTG0214 and XVS032691 induced syncytia in MT-2 cells, and used CXCR4 as coreceptor. Isolates XJN0021, XJN0091, or SHXDC0041 did not induce syncytia, and used CCR5 as coreceptor. Overall neutralization sensitivity differed among four representative strains: HIV-1 XVS032691>LTG0214>XJN0091≈SHXDC0041. Conclusion The neutralization sensitivity of HIV isolates is linked with the phenotype of isolates, in which syncytium-inducing (SI) or CXCR4-tropic (X4) viruses are more easily neutralized than non-syncytium-inducing (NSI) or CCR5-tropic (R5) viruses. The genetic subtypes based on the phylogeny of env sequences are not classical neutralization serotypes.
文摘CD8 engagement with class I major histocompatibility antigens greatly enhances T-cell activation, but it is not clear how this is achieved. We address the question of whether or not the antibody-mediated ligation of CD8 alone induces transcriptional remodeling in a T-cell clone, using serial analysis of gene expression. Even though it fails to induce overt phenotypic changes, we find that CD8 ligation profoundly alters transcription in the T-cell clone, at a scale comparable to that induced by antibody-mediated ligation of CD3. The character of the resulting changes is distinct, however, with the net effect of CD8 ligation being substantially inhibitory. We speculate that ligating CD8 induces weak, T-cell receptor （TCR）-mediated inhibitory signals reminiscent of the effects of TCR antagonists. Our results imply that CD8 ligation alone is incapable of activating the T-cell clone because it fails to fully induce NFAT-dependent transcription.
文摘Objective: To construct bicistronic expression vector with RANTES and SDF-1 genes, the ligands of HIV-1 principal coreceptors, and identify its expression. Methods: RANTES-KDEL was amplified from plasmid pCMV-R-K by PCR and cloned into eukaryotic expression vector pCMV-S/K. Gene transfection into HeLa cells was carried out by lipofectin. Indirect immumofluorescence and radioimmunoprecipitation were used to confirm the expression of RANTES and SDF-1. Results: The construction of pCMV-R-K-S-K was confirmed by enzymatic digestion and sequencing. RANTES and SDF-1 were shown expressed in HeLa cells by indirect immumofluorescence and radioimmunoprecipitation. Conclusion: pCMV-R-K-S-K was constructed and expressed in cell line Hela successfully, which will contribute to further study of gene therapy of AIDS by HIV-1 coreceptors knockout.
文摘HIV-1 infection requires the expression of CD4＋ molecules in colligation with C-C chemokine receptor type 5 （CCR5） and C-X-C chemokine receptor type 4 （CXCR4） as the major coreceptors. The role of SNP in 3＇ untranslated region ofSDF-1 （SDF1-3 ＇A） and low copy number （CN） of the CCL3L1 gene is reported to confer increased resistance to HIV-1 infection. The aim of the present study was to analyze the combinatorial effect of both the variations in protection towards HIV-1 infection in Indian population. The combinatorial effect of genetic variation in terms of SNP in SDF-1 gene and CCL3L1 CN was investigated in 105 healthy individuals and 78 HIV-I patients. Genotyping of SDF-1 was performed by RFLP-PCR and CCL3L1 by real-time PCR using TaqMan chemistry. The genotype frequency distribution of SDF-1 was found to be （SDF-1/SDF-I： 65.4%, SDF-1/SDF1-3＇A： 29.5% and SDFI-3＇A/SDF1-3＇A- 5.1%） in HIV patients as compared to （SDF-1/SDF-I： 64.8%, SDF-1/SDF1-3＇A： 30.5% and SDF1-3 ＇A/SDF1-3 ＇A： 4.7%） in healthy individuals, whereas a range of 1 to 6 copies per diploid genome was observed for CCL3L1 gene.
基金This project was funded by the National Natural Science Foundation of China(No:397706830)
文摘Objective: Allelic polymorphisms of CCR5△32CCR2b-64I,CX3CR1-2491280M and SDF1-3'A associatedwith HIV-1 infection and disease progression wereinvestigated in indigenous Uygur populations from theXinjiang Uygur Autonomous Region of China. Methods: The study population comprised 316 healthyUygur subjects with an age range of 1-80 years old, fromwhom whole peripheral blood samples were collected andnone were HIV-1 seropositive. Genomic DNA samples werepurified using a Qiagen Blood Kit. Genotyping of theaforementioned four alleles was performed using PCR orPCR/RFLP assay, and further confirmed by direct DNAsequencing. Results: The allelic frequencies in Chinese Uygurpopulation were as follows: 3.48% for CCR5△32; 19.45% forCCR2b-64I; 13.8% for CX3CR1-2491280M haplotype, and20.41% for SDF1-3'A. Mutant allele distributions amongUygur populations were in accordance with theHardy-Weinberg equilibrium. No statistical difference wasfound between the frequency of the three HIV coreceptors andtheir respective ligand genes. Conclusion: The frequency of SDF1-3'A andCX3CR1-2491280M haplotypes in these Uygur populationswas similar to that of Caucasian people, while the frequency ofthe CCR2b-64I haplotype more closely matched the HanChinese. The frequency of CCR5△A32 in Uygur populationswas between Caucasian and Hall frequencies, the more closelymatching the frequency in Medi-Asia people. No geneticlinkage between any two of the three HIV coreceptor geneswas found, but obvious genetic linkages existed betweenCX3CR1-249I and CX3CR1-280M,with even higher linkagedegrees than Caucasian people.
文摘Limited genetic information is available concerning the polymorphisms of HIV-1 resistant genes in indigenous Chinese populations. The aim of this study is to identify the allelic frequencies of the chemokine and chemokine receptor genes in the Chinese mainland. Genomic DNA samples extracted from whole blood of 2318 subjects were analyzed by using PCR or PCR/restriction fragment length polymorphism (RFLP) assays, and further confirmed by direct DNA sequencing. Higher frequencies of mutant CCR2-64I (19.15%-28.79%) and SDF1-3’A (19.10% -29.86%) alleles were found in subjects of 8 ethnic groups in the Chinese mainland. In contrast, the △32 mutation in CCRS gene occurs at a very low frequency (0.0016, n=1287) in Han population. A relatively high frequency of CCR5-wt/△32 heterozygotes was observed in Uygurian and Mongolian populations. No A32 mutation allele was detected in Tibetan and other 4 ethnic groups in Yunnan Province. There was no CCR5-m303 mutation in subjects of any ethnic group in the Chinese
基金This study was supported by the grants from the Ministry of Science and Technology of People's Republic of China(No.2005CB523103 and No.2005CB522903)the US NIH grants(No.U19AIS1915-03)
文摘The chemokine receptors CCR5 and CXCR4 play an important role as coreceptors for human immunodeficiency virus type 1 （HIV-1） entring into cells. HIV-1 isolates can be distinguished by the chemokine coreceptors. Nonsyncytium inducing （NSI）, macrophage tropic viruses utilizing CCR5, are called R5 viruses; syncytium inducing （SI） isolates use CXCR4 and known as X4 viruses. R5 viruses generally are associated with latent stage of infection and X4 viruses with later,
基金supported by the grants from the National Natural Science Foundation of China(39993430-2)the National 863 Foundation(2003AA205009)the Foundation of Shanghai Sci-Tech Committee(04JC14085).
文摘To elucidate the structures of SLA-DR(swine leukocyte antigen DR)genes of three Chinese pig strains (Gz,Bm and Yn),the SLA-DRA and SLA-DRB cDNA were amplified by RT-PCR and subjected to determine the sequences.The whole structures of SLA-DRA alleles are identical among three strains,consisting of 759 nucleotides including an open reading frame(ORF),and are shared with those reported from NIH minipigs SLA-DRA^c and SLA-DRA^d.The same length of the ORF-containing SLA-DRB genes of three Chinese pig strains was also identified.They are composed of 801 nucleotides encoding a xenogeneic antigen molecule of 266 amino acid residues.The nucleotide sequences of the SLA-DRB genes,however,are different when compared either among the three strains or with the published data of SLA-DRB sequences,which allowed our novel SLA-DRB alleles receiving their accession numbers AY102479,AY102480 and AY102481 from the GenBank.This study further reveals that the phylogenic homologies of MHC DR or DR-like genes in structures of nucleotides and deduced amino acids between Chinese pigs(SLA)and human(HLA-DRB1*0901)are better than those between pigs and mice (H-2~b Eβ).High similarities were also found for DRα-DRβ heterodimers between Chinese pigs and human in terms of amino acids sequences critical for binding with human CD4 coreceptor molecule,which are better than those between SLA-DR and H-2 I-E molecules.A functional test indicated that,by cotransfection with Bm-DRA and Bm-DRB genes,the Bm-DR molecule-expressed L929 cells could stimulate human T cells quite well in a xenogeneic reaction in presence of human APCs.Cellular & Molecular Immunology.2004;1 (3):212-218.
