OBJECTIVETo evaluate the association of cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) + 49A/G polymorphism with type 1 diabetes mellitus (T1DM) in children.

METHODSPapers about the association of CTLA4+49A/G polymorphism with T1DM in children were collected by searching PubMed, EBSCO, CBM, CNKI, and Wanfang Data. A meta-analysis was performed to examine differences in the genotypes (AG, GG, and GG+AG) and G allele at position 49 of the CTLA-4 gene between a childhood T1DM group and a control group.

RESULTSA total of 10 papers involving 1084 T1DM children and 1338 healthy children were included. The Meta-analysis was performed to evaluate the association of the genotypes (AG, GG, and GG+AG) and the G allele at position 49 of the CTLA-4 gene with T1DM using a fixed effect model according to the heterogeneity test results of all studies. The pooled OR values (95% CI) were 1.13 (0.97-1.33), 1.42 (1.16-1.75), 1.20 (1.03-1.40), and 1.21 (1.09-1.33), suggesting a significant difference in genotypes (AG, GG, and GG+AG) and the G allele at position 49 of the CTLA-4 gene between the two groups.

CONCLUSIONSCTLA-4 +49A/G polymorphism is associated with T1DM in children.

CTLA-4 Antigen ; genetics ; Diabetes Mellitus, Type 1 ; genetics ; Genotype ; Humans ; Polymorphism, Genetic

OBJECTIVETo investigate the expression of cytotoxic T lymphocyte associated antigen-4 (CTLA-4) in patients with idiopathic dilated cardiomyopathy (IDC) and to explore genetic susceptibility to IDC caused possibly by single nucleotide polymorphism (SNP) of CTLA-4 gene promoter.

METHODSPCR-restriction fragment length polymorphism techniques were used to analyze the SNPs of CTLA-4 gene at position -1772, -1661 and -318 in the promoter region. Serum sCTLA-4, IFN-gamma and IL-4 were tested by ELISA.

RESULTSsCTLA-4 levels of IDC patients were associated with the haplotype and genotype. Patients with -1772 TC genotype or -1772 TC -1661 AA, -1772 TC -1661 AG haplotypes had higher sCTLA-4 levels than patients with other haplotypes did. The frequency of -1772 TC genotype was significantly high in patients with low ejection factor(EF) values. Whereas the frequencies of -1661 G allele and -1661 GG genotype were lower in IDC patients. Levels of IL-4 were increased in IDC group.

CONCLUSIONPatients with IDC have an aberrant expression of the CTLA-4 products, and the -1772 C/T and -1661 A/G polymorphisms. The two SNPs may function as genetic markers for disease susceptibility.

Antigens, CD ; genetics ; CTLA-4 Antigen ; Cardiomyopathy, Dilated ; genetics ; Female ; Haplotypes ; Humans ; Male ; Polymorphism, Single Nucleotide ; Promoter Regions, Genetic ; genetics

OBJECTIVETo investigate the association between CTLA-4 gene polymorphism and Henoch-Schönlein purpura (HSP) in children.

METHODSSixty children who were diagnosed with HSP were enrolled as the case group, consisting of 33 males and 27 females. Thirty healthy children were enrolled as the control group. The patients were further divided into HSP nephritis (HSPN) and non-HSPN groups (n=30 each) according to the presence or absence of nephritis. Polymerase chain reaction-restriction fragment length polymorphism was used to analyze the genotype and allele frequencies at +49 and -1722 loci.

RESULTSAA, AG, and GG genotypes were detected at +49; neither genotype nor allele frequencies showed significant differences between the case and control groups, between the HSPN and non-HSPN groups, and between male and female patients (P>0.05). TT, TC, and CC genotypes were detected at -1722; neither genotype nor allele frequencies showed significant differences between the case and control groups and between male and female patients (P>0.05). There were significant differences in CC genotype frequency and T and C allele frequencies between the HSPN and non-HSPN groups (P<0.05). Combinational analysis of +49 A/G and -1722 T/C showed no significant differences in the genotype frequency between the case and control groups and between male and female patients (P>0.05). GG-CC combination showed a significant difference between the HSPN and non-HSPN groups (P<0.05).

CONCLUSIONSCTLA-4 +49 A/G polymorphism is not associated with HSP. CC genotype and C allele of CTLA-4 -1722 and the combination of GG at +49 A/G and CC at -1722 T/C may be risk factors for HSPN.

CTLA-4 Antigen ; genetics ; Child ; Child, Preschool ; Female ; Genotype ; Humans ; Male ; Polymorphism, Genetic ; Purpura, Schoenlein-Henoch ; genetics

OBJECTIVETo investigate the association of cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) gene A/G polymorphism with susceptibility to diabetes mellitus in Han Chinese.

METHODSAn A/G transition at position 49 of exon 1 was analyzed in 31 patients with type 1 diabetes, 31 patients with type 2 diabetes, and 36 controls were analyzed by polymerase chain reaction-restriction fragment length polymorphism analysis.

RESULTSA highly significant increase in the frequency of the G allele was seen in patients with type 1 diabetes compared with controls (66.1 % vs. 34.7%, respectively; P < 0.0005; OR = 3.670) . This reflected an increase in the GG genotype in patients (48.4% vs. 22.2%, respectively; P =0.025; OR =3.281) and a significant decrease in the AA genotype (16.1 % vs. 52.8%, respectively; P = 0.002). The allele frequencies of A and G in patients with type 2 diabetes were not significantly different from controls(A/G, 50.0/50.0% vs. 65.3/34.7%; P = not significant) . The distribution of genotype, however, differed significantly. This difference reflected an increase in the AG genotype in patients (54.8% vs.25.0%, respectively; P=0.012; OR=3.643) and a decrease in the AA genotype (22.6% vs. 52.8%, respectively; P=0.011).

CONCLUSIONSCTLA-4 49 AA is protective from diabetes mellitus, whereas, CTLA-4 49 G allele (both as homozygotes and as heterozygotes ) confers an increased risk of diabetes mellitus.

Abatacept ; Antigens, CD ; Antigens, Differentiation ; genetics ; CTLA-4 Antigen ; China ; ethnology ; Diabetes Mellitus ; genetics ; Humans ; Immunoconjugates ; Polymorphism, Genetic

Antigens, CD ; genetics ; metabolism ; Apoptosis ; genetics ; CTLA-4 Antigen ; Child ; Female ; Glomerulonephritis ; genetics ; pathology ; Humans ; Male ; Nephrosis, Lipoid ; genetics ; pathology ; Polymorphism, Genetic

OBJECTIVETo investigate and compare the expression pattern and level of targeted anti-caries plasmids encoding different-size antigens in eukaryotic cells.

METHODSThe A-P fragment of PAc (surface protein antigen) was removed from pGJA-P encoding the signal peptide, extracellular domains of human CTLA-4, human Ig hinge, CH2 and CH3 domains, A-P fragment of PAc and GLU (glucan binding domain) region of GTF-I of Streptococcus mutans, to obtain the plasmid pGJGLU. pCI vector skeleton of pGJA-P or pGJGLU was replaced by pVAX1 to construct plasmids pGJA-P/VAX and pGJGLU/VAX. CTLA4-Ig-GLU fragment was removed from pGJGLU and inserted into the vector pEGFP-N1 to obtain the recombinant plasmid pGJGLU/GFP. The CHO cells were transfected with those plasmids by using liposome and the expression of fusion protein was observed with fluorescence microscope. ELISA was used to detect the expression level of fusion proteins in cultured supernatants.

RESULTSSpecific vesicles with green fluorescence could be observed in the CHO cells transfected with pGJGLU/GFP. The recombinant fusion protein could be detected in the cultured supernatants of CHO cells transfected with pGJA-P/VAX, pGJGLU/VAX and pGJGLU/GFP, of which the concentration was different. The highest concentration of recombinant fusion protein was observed in the supernatants of CHO cells transfected with pGJGLU/VAX.

CONCLUSIONSCTLA-4 targeted fusion protein could be expressed and secreted by eukaryotic cells. The size of antigen may affect the expression level of CTLA-4 targeted anti-caries DNA vaccine.

Animals ; Antigens, CD ; genetics ; immunology ; metabolism ; CTLA-4 Antigen ; Cricetinae ; Dental Caries ; prevention & control ; Humans ; Recombinant Fusion Proteins ; genetics ; immunology ; metabolism ; Vaccines, DNA ; genetics ; immunology

OBJECTIVETo investigate the influence of local application of cytotoxic lymphocyte antigen 4-Ig (CTLA4-Ig) adenovirus on the burn wound with alloskin grafting upon the murine immune function.

METHODSSixty BALB/c mice were randomly divided into A (operation control), B (CTLA4-Ig transfection) and C (normal control) groups, with 20 mice in each group. Skin wounds (full-thickness loss) sized 1.5 cm x 1.5 cm were created on the backs of mice in A and B groups. Then the skin grafts of the same size obtained from C57BL mice were grafted into the skin wounds. 0.1 g of cross-linking polyacrylic resin (carbomer cream) without adenovirus was daubed onto the wounds in A group, and the same amount of carbomer cream with adenovirus in titers of 5 x 10(9)/L was daubed onto the wounds in B group, while no treatment was given in C group. 1 ml of 10% SRBC (sheep red blood cell) was injected intraperitoneally to all the mice of the three groups on the 1st post injury day (PID). Splenocytes from BALB/c, C57BL and Kunming mice were harvested for mixed lymphocyte culture on 7, 14, 21 and 28 PIDs. Agglutination assay was used in the same time to detect the SRBC antibody titers.

RESULTSThe reaction of murine splenocytes in B group to the donor (C57BL) splenocytes was suppressed in a specific way (P < 0.05) within 14 PIDs. There was no difference in the titers of anti-SRBC antibody among the 3 groups (P > 0.05).

CONCLUSIONLocal application of CTLA4-Ig recombinant adenovirus exhibited no influence on the murine humoral immunity, but might induce systemic and specific T cell tolerance in immunity system.

Adenoviridae ; genetics ; Animals ; Antigens, CD ; immunology ; CTLA-4 Antigen ; Immune Tolerance ; immunology ; Male ; Mice ; Mice, Inbred BALB C ; Skin Transplantation ; immunology ; Transplantation, Homologous ; immunology

OBJECTIVETo explore the role of indirect antigen presentation pathway on the immunogenecity of epidermal cells.

METHODSHuman epidermal cells (HEC), allogeneic human peripheral blood lymphocytes (PBL) and mononuclear cells (PBM, including monocytes) were isolated and cultured in vitro. HECs were transfected by human-originated CTLA4Ig-adenovirus vector. The CTLA4Ig expression was observed. Allogeneic PBLs or PBMs were added to the transfected and non-transfected HECs with simple cultured PBLs and PBMs as the control. The proliferation of PBL and PBM was determined by (3)H-TdR incooperation.

RESULTSHECs could be successfully transfected by CTLA4Ig-adenovirus vector and expressed corresponding proteins. The non-transfected HECs could stimulate slight proliferation of allogeneic PBLs (P < 0.05) and stimulate remarkable proliferation of PBMs (including monocytes) (P < 0.05). The proliferation reaction of PBLs and PBMs decreased significantly (P < 0.05) after being stimulated by HEC which was modulated by CTLA4Ig genes.

CONCLUSIONIndirect antigen presentation pathway might play important roles in the HEC immunogenicity which could be evidently inhibited by CTLA4Ig.

Adenoviridae ; genetics ; Antigen Presentation ; immunology ; physiology ; Antigens, CD ; Antigens, Differentiation ; genetics ; immunology ; CTLA-4 Antigen ; Cell Division ; immunology ; Cells, Cultured ; Coculture Techniques ; Epidermis ; cytology ; immunology ; metabolism ; Genetic Vectors ; genetics ; Humans ; Leukocytes, Mononuclear ; cytology ; immunology ; Lymphocytes ; cytology ; immunology ; Signal Transduction ; Transfection

To evaluate the efficiency of three in vitro refolding methods for a humanized single-chain Fv antibody against human CTLA4(CD152) expressed in E. coli, the denatured and purified inclusion bodies (IBS) were refolded by dilution, dialysis and in situ refolding via Immobilized Metal-Ion-Affinity Chromatography (IMAC), respectively. The concentration of refolded scFvs was examined by Bradford method. And the antigen binding activity of the refolded scFvs was analyzed by indirect cell-ELISA. The highest and lowest refolding yields could be obtained by dialysis and in situ refolding via IMAC, respectively. The binding activity of the refolded scFv by dialysis was 1.95-fold higher than that by dilution, 4.13-fold higher than that by in situ refolding via IMAC (GSH/GSSH excluded) and 3.63-fold higher than that by in situ refolding via IMAC (GSH/GSSH included), respectively. In conclusion, a high refolding yield and binding activity of scFv with natural conformation could be obtained by dialysis in the condition of 0. 15 mol/L sodium chloride, 50 mmol/L Tirs-HCl, pH 8. 0 buffer containing 3 mmol/L reduced glutathione and 1 mmol/L oxidized glutathione for 48 hours at 4 degrees C.
Antigens, CD ; biosynthesis ; genetics ; immunology ; Antigens, Differentiation ; biosynthesis ; genetics ; immunology ; CTLA-4 Antigen ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Humans ; Immunoglobulin Fc Fragments ; biosynthesis ; genetics ; immunology ; Immunoglobulin Variable Region ; biosynthesis ; genetics ; immunology ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; immunology

OBJECTIVETo construct and detect the targeted anti-caries fusion DNA vaccine pGJA-P encoding the A-P fragment of pac, glu fragment of gtfB and extracellular region of the human CTLA4 and the Fc region of human Iggamma(1) gene for the targeting antigen to APC.

METHODSThe extracellular region of the human CTLA4 and the Fc region of human Iggamma(1) genes were amplified by RT-PCR from human lymphocytes, and the genes were cloned into pUC(m-T) vector respectively. After sequencing, Fc region of human Iggamma(1) gene was cloned to the downstream of CTLA4 gene fragment as the recombinant plasmid pGJ. The fusion gene was then inserted into the plasmid pGLUA-P to get the recombinant plasmid pGJA-P. The CHO cells were transfected with liposome and the expression of fusion protein in cultured supernatants were detected using Western blotting.

RESULTSThe plasmids pGJ and pGJA-P carried the CTLA4-Ig fusion gene and CTLA4-Ig fusion gene, A-P fragment of pac gene and glu fragment of gtfB gene respectively. The expressed protein could response to specific anti-PAc antibody.

CONCLUSIONThe targeted fusion anti-caries DNA vaccine pGJA-P is constructed successfully and expressed in eukaryotic cells correctly.

Animals ; Antigens, CD ; Antigens, Differentiation ; genetics ; immunology ; CHO Cells ; CTLA-4 Antigen ; Cricetinae ; Dental Caries ; prevention & control ; Glucosyltransferases ; genetics ; immunology ; Humans ; Recombinant Fusion Proteins ; genetics ; immunology ; Streptococcus mutans ; genetics ; immunology ; Vaccines, DNA ; genetics ; immunology