新疆妇女宫颈炎中TAP基因与HPV16的相关性

目的初步探讨TAP基因与HPV16在宫颈炎中的相关性。方法以宫颈炎(汉族84例,维族90例)为病例组,对照组为正常女性全血标本(汉族57例,维族58例)提取DNA采用PCR-扩增阻碍突变系统(PCR-ARMS)扩增TAP1和TAP2基因,同时PCR扩增HPV16特异性引物。结果 TAP1A,TAP1C在宫颈炎中单倍体型分布频率明显低于正常对照组(P0.05),TAP2D,TAP2E在宫颈炎中单倍体型分布频率明显高于正常对照组(P0.05),TAP1A,TAP1C,TAP2D,TAP2E在宫颈炎中单倍体型分布频率与HPV16无相关性。结论 TAP1A,TAP1C,TAP2D,TAP2E在宫颈炎中单倍体型分布频率与HPV16无相关性,这可能是地理分布及种族差异有关。     

Biological function of the soluble CEACAM1 protein and implications in TAP2-deficient patients

Interactions of natural killer (NK) cells with MHC class I proteins provide the main inhibitory signals controlling NK killing activity. It is therefore surprising to learn that TAP2-deficient patients suffer from autoimmune manifestations only occasionally in later stages of life. We have previously described that the CEACAM1-mediated inhibitory mechanism of NK cytotoxicity plays a major role in controlling NK autoreactivity in three newly identified TAP2-deficient siblings. This novel mechanism probably compensates for the lack of MHC class I-mediated inhibition. The CEACAM1 protein can also be present in a soluble form and the biological function of the soluble form of CEACAM1 with regard to NK cells has not been investigated. Here we show that the homophilic CEACAM1 interactions are abrogated in the presence of soluble CEACAM1 protein in a dose-dependent manner. Importantly, the amounts of soluble CEACAM1 protein detected in sera derived from the TAP2-deficient patients were dramatically reduced as compared to healthy controls. This dramatic reduction does not depend on the membrane-bound metalloproteinase activity. Thus, the expression of CEACAM1 and the absence of soluble CEACAM1 observed in the TAP2-deficient patients practically maximize the inhibitory effect and probably help to minimize autoimmunity in these patients.     

Polymorphisms of TAP 1 and TAP2 genes in Graves' disease

Graves' disease is an autoimmune disorder in which HLA DQA1*0501 and DQB1*0201 confer predisposition. The genes for transporters associated with antigen processing (TAP1 and TAP2) locate near to HLA DQ coding regions and display only a limited degree of polymorphism. Since polymorphisms of TAP might influence susceptibility to Graves' disease by a possibly different selection of antigenic peptides, we investigated sequence variants of TAP1 and TAP2 genes in 235 patients with Graves' disease and 218 random healthy controls by polymerase chain reaction (PCR) followed by sequence specific oligonucleotide analysis (SSO), single strand conformational polymorphism (SSCP) analysis and amplification refractory mutation system (ARMS). TAP1*0301 (Val-333/Asp-637: 71% vs. 55% in controls. p< .0008, RR=2.05) and TAP2*0101 (Val-379/Ala-565/Thr-665/stop-687: 83% vs. 69% in controls, p< .003, RR=2.20) showed a positive association with Graves' disease whereas TAP1*0401 a negative (Ile-333/Gly-637: 4% vs. 13% in controls, p< .001, RR=0.25). After selection of patients and controls for HLA DQA1*0501 a similar association was found for TAP1*0301 (72% vs. 50% in controls, p< .002, RR=2.63) and TAP1*0401 (4% vs. 16% in controls, p< .004, RR=0.22), when matching for HLA DQB1*0201 as well as for TAP1*0401 (3% vs. 16% in controls, p< .005, RR=0.18). Our findings indicate that the positive association of TAP1*0301 and the negative of TAP1*0401 with Graves' disease cannot only be explained by linkage disequilibrium between TAP alleles and HLA DQ. Therefore, these TAP alleles contribute to genetic susceptibility in Graves' disease as additional permissive and protective factors.     

Association of TAP 1 and 2 gene polymorphisms with human immunodeficiency virus-tuberculosis co-infection

Major histocompatibility complex (MHC) class I binding peptides are carried from cytosol to the lumen of the endoplasmic reticulum (ER) by transporter associated with antigen processing (TAP), an integral ER membrane protein composed of two subunits, TAP1 and TAP2. Polymorphism in TAP genes may influence these proteins further affecting the antigen peptide presentation, indirectly resulting in the viral escape mechanism from cell-mediated immunity in human immunodeficiency virus (HIV). Our aim was to study the influence of these polymorphism in study groups with HIV-tuberculosis (TB) (n = 110), TB (n = 105), and HIV (n = 130) compared with healthy controls (n = 183), using the tetraprimer amplification refractory mutation system (ARMS)-polymerase chain reaction method. Our results demonstrated that the GG genotype at TAP1 position 333 and GA genotype at TAP1 position 637 were positively associated with HIV-TB co-infection and these genotypes may act as a risk factor for developing TB co-infection in HIV-positive individuals.     

Abnormal Development at Early Postimplantation Stage in Mouse Embryos After Preimplantation Genetic Diagnosis

Preimplantation genetic diagnosis (PGD) is an established procedure for the genetic analysis of embryos. To assess the effect of the procedure on early embryonic development, we generated a murine experimental system, including mice implanted with biopsied in vitro cultured embryos, control mice implanted with in vitro cultured embryos without biopsy, and mice with naturally conceived embryos. Embryos at the 7.5‐dpc stage were isolated from all three groups and the embryo implantation rate, the survival rate of implanted embryos, and the developmental stage of surviving embryos were carefully assessed and compared among all three groups. We found the implantation rate was similar between biopsied and control group embryos (67.92% vs. 66.67%). However, the survival rate of implanted embryos in the biopsied group (49.31%) was significantly lower than that of the control (60.91%) and normal groups (96.24%) at 7.5 dpc. In addition, the survival rate of control group embryos was significant lower than that of normal group embryos. Classification of the precise developmental stages of randomly selected live implanted embryos at 7.5 dpc revealed no differences among the three groups. Our results indicate that blastomere biopsy does not adversely affect embryo implantation. The PGD procedure, in particular blastomere biopsy, increases the rate of embryo death at 4.5–7.5 dpc, but does not affect the development of surviving 7.5 dpc embryos. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.     

An update meta-analysis and systematic review of TAP polymorphisms as potential biomarkers for judging cancer risk

Objective

Transporter associated with antigen processing protein (TAP) is a heterodimer protein consist of TAP1 and TAP2, act a pivotal part in the immune surveillance. In recent days, controversial relationships were reported between TAP polymorphisms and cancer risk, thus, a systematic meta-analysis was performed to resolve this discrepancy.

TAP1 and TAP2 gene polymorphisms in Korean patients with allergic rhinitis

Antigen peptides are actively transported across the endoplasmic reticulum by the transporters associated with antigen presentation (TAP). TAP genes polymorphism could influence the selection process that determines which antigen peptides play a role in the pathogenesis of allergic rhinitis. The aim of this study was to investigate the association of TAP genes polymorphism with allergic rhinitis. TAP1 and TAP2 genotyping were performed on 110 allergic rhinitis patients and 107 healthy controls. TAP1 polymorphic residues at codons 333 and 637, and TAP2 polymorphic residues at codons 379, 565, 651, and 665 were analyzed by the amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). Analysis of TAP1 gene polymorphism demonstrated decreased frequencies of Ile/Val genotype at codon 333, Asp/Gly genotype at codon 637, and haplotype A and B in allergic rhinitis patients when compared to controls (p<0.05). However, there was no significant difference in the genotype, phenotype, or allele frequencies at four TAP2 codons between controls and allergic rhinitis patients. In conclusion, TAP1 gene polymorphism may be an important factor contributing to the genetic susceptibility in the development of allergic rhinitis in the Korean population.     

New TAP2 polymorphisms in Africans

Abstract: Polymorphisms in genes encoding transporters associated with antigen processing (TAP) have been associated with heterogeneity of disease progression in HTV-l-infected homosexual men. In our recent AIDS-related studies of cohorts from Rwanda and Zambia, four new polymorphic sites in the TAP2 coding region were detected by single-strand conformation polymorphism (SSCP) and confirmed by bi-directional nucleotide sequencing and restriction enzyme digestion. The first, a substitution of Thr (GCC) for Ala (ACC) at codon position 374 in exon 5, was found in about 13% of Rwandans and Zambians ( n =213). The remaining 3 new polymorphisms were seen in the 7th exon with changes of 458Thr-ACG to ACA, 466Gly-GGG to GGA, and 467Val-GTT to Ile-ATT, respectively. These 3 variants occurred exclusively on the same chromosome and appeared to have arisen together from the 374Thr-bearing allele. Analyses of the relationship between the 374Thr-457Ile segment and the nearby markers in DQB1 and DRB1 suggested the existence of a unique extended haplotype related to these newly identified variants.     

Mammalian Expression Cloning of Two Human Trophoblast Suppressors of Major Histocompatibility Complex Genes

PROBLEM: Human trophoblasts suppress interferon-gamma (IFN-gamma)-simulated expression of major histocompatibility complex (MHC) class II genes and thereby protect the conceptus from maternal immune attack. The mechanism of this suppression is poorly understood. METHOD OF STUDY: IFN-gamma-responsive HeLa cells were stably transfected with trophoblast cDNA expression libraries and screened by negative immunoselection with an antibody to HLA-DR. RESULTS: Two suppressor cDNAs were isolated. One encoded the untranslated RNA trophoblast STAT utron (TSU), which blocked STAT1 nuclear translocation and can theoretically form triplex RNA-DNA at the class II transactivator gene promoters. The other encoded the N-terminal 28 residues of chorionic somatomammotropin (hCS). TSU-related genes were detected in human and macaque but not in mouse, genomic DNA. CONCLUSIONS: The genetics of two human trophoblast MHC suppressors suggest that these functions have been gained in human placenta in recent evolutionary history. TSU and hCS play critical roles in suppression of MHC genes, which may lead to silencing by DNA methylation.     

Analysis of allelic variation of the TAP2 gene in sarcoidosis

Sarcoidosis is a systemic granulomatous disease and the DRB1 gene of the DR subregion has been implicated for determining the genetic susceptibility to the disease. We evaluated the allelic variation of the TAP2 gene using the PCR-RFLP method as well as the mismatched PCR-RFLP method in 82 Japanese patients with sarcoidosis and 92 healthy controls. A new allele, TAP2*0103 and a new polymorphic variation at codon 577 in addition to TAP2*0101, TAP2*0102 and TAP2*0201 have been recognized in the Japanese subjects. No significant differences were observed in the frequencies of any TAP2 alleles or dimorphism at codon 577 between the patients and healthy controls. Polymorphic variation of the TAP2 gene does not confer the susceptibility to sarcoidosis.     

Susceptibility to Murine Experimental Autoimmune Oophoritis Is Associated With Genes Outside the Major Histocompatibility Complex (MHC)

PROBLEM: Neonatal thymectomy induces experimental autoimmune oophoritis in certain strains of mice, and this serves as a model for human autoimmune oophoritis. Because strong MHC associations have been noted in human autoimmune conditions, we investigated the role of MHC in determining susceptibility to murine experimental autoimmune oophoritis. Strain A mice are highly susceptible to post-thymectomy autoimmunity, whereas strain B10 mice are relatively resistant. The availability of congenic strains of mice makes it possible to separate the effects of genetic background and specific H-2 haplotype. METHODS: We neonatally thymectomized A and B10 background female mice, and their H-2 congenic counterparts, and then evaluated the resulting ovarian disease at age 6 weeks. RESULTS: A. By mice, which have the A background and the H-2^b haplotype, developed severe disease equivalent to strain A mice. Similarly, B10.A mice, which have the B background and the H-2^a haplotype, failed to develop disease. Thus, H-2^a haplotype did not convey disease susceptibility. CONCLUSIONS: Our findings suggest that immune-regulatory regions outside the H-2 locus play an important role in determining susceptibility to murine post-thymectomy autoimmune oophoritis. This is in accord with our previous findings in women that showed no association between MHC and premature ovarian failure. Thus, in this respect this model is similar to human autoimmune ovarian failure. This suggests that the non-MHC genes conveying susceptibility to autoimmune oophoritis in mice might represent similar predisposing genes for premature ovarian failure in women.     

Polymorphism of TAP1 and TAP2 in Japanese patients with rheumatoid arthritis

Contribution of polymorphism of transporter associated with antigen processing 1 and 2 (TAP1 and 2) alleles to pathogenesis of Japanese rheumatoid arthritis (RA) was studied in 92 RA patients by PCR-RFLP. The allele frequency of TAP2A was slightly low (38.0%) and the frequencies of TAP2B and TAP2C were slightly high (39.7% and 17.9%) in RA, but these differences were not significant. These increases and decrease were due to the positive or negative associations with HLA-DRB1*0405. It was very likely that slight differences in TAP2A, TAP2B and TA2C in RA were secondary phenomenon reflecting an increase in HLA-DRB1*0405. The prevalence of TAP2E allele was low (3.3%, P <0.01, P_c=not significant) and not correlated with HLA-DRB1*0405.     

Analysis of TAP1 and TAP2 polymorphism of mother-infant in Chinese patients with pre-eclampsia

To analyze the polymorphism of TAP gene and the shared rates of alleles between mothers and their infants inChinese patients with pre-eclampsia,TAP1 and TAP2 genotyping was performed by the amplification refractorymutation system-polymerase chain reaction(ARMS-PCR)in 42 patients,106 normal pregnant women,and theirneonates.The allelic frequency of TAP and the alleles shared in maternal-fetus were compared and analyzed in thetwo groups.Our results showed that,with totally eight alleles of TAP1 and TAP2 examined in the samples,nosignificant difference was found in allelic frequencies between pre-eclampsia group and control group,as well asbetween mothers and their neonates.Similar finding was obtained in the comparison with shared alleles.Inconclusion,our results do not support a role for the polymorphisms of TAP in the etiology of pre-eclampsia.Cellular & Molecular Immunology.2005;2(2):141-144.     

Transporter associated with antigen processing (TAP) 1 gene polymorphisms in patients with hypersensitivity pneumonitis

Hypersensitivity pneumonitis (HP) is a lung inflammatory disease caused by the inhalation of a variety of antigens. Previous studies support the role of the major histocompatibility complex (MHC) class II genes in the susceptibility to develop HP. However, the putative role of other MHC loci has not been elucidated. Transporters associated with antigen processing (TAP) genes are located within the MHC class II region and play an important role transporting peptides across the endoplasmic reticulum membrane for MHC class I molecules assembly. The distribution of single nucleotide polymorphisms (SNPs) in TAP1 genes was analyzed in 73 hypersensitivity pneumonitis (HP) patients and 58 normal subjects. We found a significant association of the allele Gly-637 (GGC) (p=0.00004, OR=27.30, CI=3.87-548.04) and the genotypes Asp-637/Gly-637 (p=0.01, OR=16.0, CI=2.19-631.21), Pro-661/Pro-661 (p=0.006, OR=11.30, CI=2.28-75.77) with HP. A significant decrease in the frequency of the allele Pro-661 (CCA) (p=0.008, OR=0.06, CI=0-0.45), the genotype Asp-637/Asp-637 (p=0.01, OR=0.17, 95% CI=0.05-0.58) and the haplotype [Val-333 (GTC), Val-458 (GTG), Gly-637 (GGC), Pro-661 (CCA)] was detected in HP patients compared with controls (p=0.002, OR=0.07, CI=0.0-0.57). These findings suggest that TAP1 gene polymorphisms are related to HP risk, and highlight the importance of the MHC in the development of this disease.     

Differential Expression and Regulation of Angiopoietin‐2 in Mouse Uterus During Preimplantation Period

Angiogenesis is crucial to successful implantation and decidualization, however, as an important angiogenic growth factor, the effect of Ang‐2 in the process of implantation and decidualization is still unknown. This study is to investigate the differential expression of Ang‐2 in mouse uterus during early pregnancy and its regulation by steroid hormones using in situ hybridization and RT‐PCR. There is no detectable Ang‐2 mRNA signal on days 1–5 of pregnancy by in situ hybridization. On days 6–8, Ang‐2 mRNA is mainly expressed in the primary decidua of mesometrial side, and the expression gradually increases. By RT‐PCR, a significantly higher level of Ang‐2 expression is observed on day 8 of pregnancy, although Ang‐2 expression can be found through days 1–8. Similarly, Ang‐2 is highly expressed in decidualized cells under artificial decidualization. In the ovariectomized mouse uterus, Ang‐2 expression gradually increases after estrogen injection and with peak levels at 12 hr, while progesterone injection can cause a decline in uterine Ang‐2 mRNA level, which reaches a nadir at 12 hr. These results suggest that Ang‐2 may play a key role in the process of mouse decidualization. Estrogen can induce the expression of Ang‐2 while progesterone can inhibit its expression in the ovariectomized mouse uterus. Anat Rec, 2012. © 2011 Wiley Periodicals, Inc.     

Major histocompatibility complex class I molecules interact with both subunits of the transporter associated with antigen processing,TAP1 and TAP2

Prior to loading antigenic peptides, assembled major histocompatibility complex (MHC) class I molecules associate with the transporter associated with antigen processing (TAP) in a complex which also includes calreticulin and a recently described component, tapasin. The interaction of MHC class I molecules has been characterized as occurring exclusively with the TAP1 chain of the TAP heterodimer. In contrast, as described here, in the TAP-deficient human cell line T2, MHC class I molecules interact with a transfected rat TAP2 polypeptide in addition to rat TAP1. Furthermore, this interaction with TAP2 also involves calreticulin and tapasin. An association with both TAP polypeptides would presumably further enhance the efficiency of peptide loading of MHC class I molecules by allowing more than one MHC class I allele proximity to the site of peptide supply on each TAP complex.     

TAP1真核表达载体的构建及其对GES-1细胞HLA-I分子表达的影响

目的:构建抗原加工相关转运蛋白TAP1真核表达载体,并观察其对HLA-I分子表达的影响。方法:采用基因重组技术,构建含人TAP1基因全长的pcDNA3.1/V5-His-TAP1真核表达质粒,并采用细胞转染、RT-PCR、Western blot以及流式细胞术(FCM)观察TAP1转染对胃黏膜上皮(GES-1)细胞HLA-I分子表达的影响。结果:以人外周血单个核细胞总RNA为模板,经RT-PCR反应获得人全长TAP1基因,以pcDNA3.1/V5-HisB为载体,经酶切、连接、转化等基因重组技术,构建了含人TAP1基因全长的pcDNA3.1/V5-His-TAP1质粒,并经测序结果证实。以GES-1作为靶细胞进行转染,经RT-PCR和Westernblot证实,转染后TAP1基因表达明显增加,细胞适于所构建的TAP1质粒的转染。进一步检测了TAP1转染对GES-1细胞HLA-I类分子表达的影响。结果发现,TAP1转染组HLA-A、HLA-B、HLA-C(重链)在mR-NA水平表达明显增加,β2m(轻链)mRNA水平无明显影响。FCM及Western blot检测结果表明,TAP1转染可以上调HLA-I蛋白的表达。结论:成功构建了TAP1真核表达质粒,细胞转染后TAP1表达的增加,可引起细胞表面HLA-I分子表达的相应增加,从而证实了TAP1在HLA-I抗原表达以及抗原递呈途径中的重要作用。     

Expression of Major Histocompatibility Complex Class II Subregion Products by Jejunal Epithelium in Patients with Coeliac Disease

The MHC class II subregion products (HLA-DR), HLA-DP, and HLA-DQ) were located by immunofluorescence in serial sections of ethanol-fixed, paraffin-embedded jejunal mucosa from control subjects and patients with coeliac disease (CD). DR staining was seen in a granular luminal distribution and basolaterally on surface epithelial cells in both untreated and treated CD patients and in controls. In untreated CD the crypt epithelium was positive for DR almost to the bottom of the glands. This contrasted with virtually absent glandular DR staining in controls and weak staining including only the upper part of the crypts in 5 out of 11 treated patients. HLA-DP was present apically in the surface epithelium in all untreated patients, in 5 out of 11 treated patients, and in 4 out of 11 controls. HLA-DQ appeared only in three untreated patients and was restricted to patches of surface epithelium. The number of intraepithelial T lymphocytes per millimetre of surface epithelium was significantly higher in untreated than in treated CD patients or controls; it was also significantly higher in specimens with epithelial DP expression than in those without. This suggested that intraepithelial lymphocytes modulate epithelial class II expression.