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1.
Immune responses are elicited through antigen presentation and recognition by macrophages and T-lymphocytes, respectively. The immunomodulatory effect of vitamin D(3) on macrophage phagocytic potential with live Mycobacterium tuberculosis, spontaneous and M. tuberculosis culture filtrate antigen induced lymphocyte responses were studied in pulmonary tuberculosis patients (PTBPs) ( n = 31) and normal healthy subjects (NHSs) ( n = 43). Vitamin D(3) at a concentration of 10(-7) M significantly enhanced the macrophage phagocytosis of live M. tuberculosis in normal subjects with low phagocytic potential (less than 10%) ( p = 0.015). No such increase was observed in PTBPs. Vitamin D(3) significantly decreased the spontaneous lymphoproliferative response ( p = 0.022) and increased the apoptosis of peripheral blood mononuclear cells in PTBPs ( p = 0.024). In normals, vitamin D(3) increased the spontaneous lymphoproliferative response. An inverse correlation between macrophage phagocytosis and spontaneous response was observed in NHSs, whereas a direct correlation was seen between vitamin D(3)-treated cells in normal subjects under in vitro condition. Vitamin D(3) decreased the M. tuberculosis culture filtrate antigen induced lymphocyte response significantly in normal subjects ( p = 0.0003), while it had no influence on the lymphocyte response in PTBPs. The present study suggests that exposure to vitamin D(3) increases the phagocytic potential and spontaneous lymphoproliferative response but brings down the antigen-induced response in normals. In tuberculosis, addition of vitamin D(3) has no significant effect on antigen-induced lymphoproliferative response. This may be due to the unresponsive nature of the cells to the action of vitamin D(3) by virtue of the disease, which renders them inactive.  相似文献   

2.
Introduction  Vitamin D3, which exerts its effect through vitamin D receptor (VDR), is known for its potent immunomodulatory activities. Associations between low serum vitamin D3 levels and increased risk of tuberculosis have been reported. Study Subjects and Methods  Plasma 1,25 dihydroxy vitamin D3 levels (1,25(OH)2 D3) and ex vivo levels of VDR protein from peripheral blood mononuclear cells were studied in 65 pulmonary tuberculosis (PTB) patients and 60 normal healthy subjects (NHS) using enzyme-linked immunosorbent assay-based methods. Using real-time polymerase chain reaction (PCR), induction of VDR, cathelicidin, and CYP27B1 mRNA were studied in live Mycobacterium tuberculosis-stimulated macrophage cultures treated with or without 1,25 dihydroxy vitamin D3. VDR and CYP27B1 (-1077 A/T) gene polymorphisms were studied using PCR-based methods. Results  1,25(OH)2 D3 were significantly increased (p = 0.0004), while ex vivo levels of VDR protein were significantly decreased in PTB patients (p = 0.017) as compared to NHS. 1,25(OH)2 D3 levels were not different between variant genotypes of CYP27B1. A trend towards decreased levels of VDR protein was observed among NHS with BsmI BB and TaqI tt genotypes compared to NHS with other genotypes. Relative quantification of mRNA using real-time PCR revealed increased VDR mRNA expression in live M. tuberculosis-stimulated culture in PTB patients (p < 0.01) than normal healthy subjects. Cathelicidin mRNA expression was significantly increased in vitamin D3-treated cultures compared to unstimulated and M. tuberculosis-stimulated culture in both patients (p < 0.001) and NHS (p < 0.05). Conclusions  The present study suggests that PTB patients may have increased 1,25(OH)2 D3 levels, and this might lead to downregulation of VDR expression. Decreased VDR levels could result in defective VDR signaling. Moreover, addition of 1,25(OH)2 D3 might lead to increased expression of cathelicidin which could enhance the immunity against tuberculosis.  相似文献   

3.
We performed this study to investigate the possible association between vitamin D receptor (VDR) gene polymorphism and the focal bone erosion in rheumatoid arthritis (RA) patients in Korea. One hundred and fifty-seven RA patients were enrolled and two control groups were selected. The focal bone erosion score was assessed by modified Sharp's method. Genotyping of VDR polymorphisms was performed by polymerase chain reaction and restriction fragment length polymorphism analysis using two restriction enzyme Taq I and Bsm I. Notably, the distribution of VDR genotype in Korean population was different from Caucasians. The frequencies of "tt" and "BB" genotypes were very rare both in RA patients and in control groups. The frequency distribution of the Taq I and Bsm I genotype was not different between RA patients (TT, 93.6%; Tt, 6.4%; tt, 0%; BB, 0.6%; Bb, 5.1%; bb, 94.3%) and control groups (TT, 90.8%; Tt, 7.5%; tt, 1.7%; BB, 1.4%; Bb, 8.1%; bb, 90.5%). There was no significant difference in the focal bone erosion score (mean +/- SD) according to the VDR genotypes of RA patients (TT, 0.92 +/- 1.79; Tt, 0.4 +/- 0.79; Bb, 0.43 +/- 0.80; bb, 0.92 +/- 1.79; p > 0.05). In conclusion, these results suggest that VDR gene polymorphisms are not associated with the focal bone erosion in RA patients in Korea.  相似文献   

4.
The presence of certain vitamin D receptor (VDR) genotypes has been associated with low bone mineral density (BMD) in elderly populations as well as with accelerated bone loss in patients with rheumatoid arthritis (RA). In the present study, VDR genotypes from 120 Spanish patients with RA were investigated. Three VDR gene polymorphisms (BsmI, ApaI and TaqI) were investigated using polymerase chain reaction followed by enzymatic digestion. The distributions of VDR allelic frequencies were similar in patients and controls and therefore no influence of VDR polymorphisms on rheumatoid arthritis susceptibility could be demonstrated. However, in an analysis of the clinical features of the different VDR‐related genetic subgroups, the BB/tt genotype, defined by the BsmI and TaqI restriction site polymorphisms, was identified to be weakly associated with an early onset RA in female patients. This VDR genotype has been associated with a low BMD level in various studies. When patients were stratified according to the presence of the shared HLA epitope SE, it was found that SE + female patients bearing the BB/tt genotype showed the earliest disease onset. The mechanisms by which the VDR polymorphism is associated with RA is unknown, but they could be related to the immunoregulatory properties of vitamin D.  相似文献   

5.
Vitamin D receptor (VDR) gene variants are shown to regulate immune response in tuberculosis. We studied the influence of VDR promoter (Cdx-2 and A1012G), 3' untranslated region (Apa I, Bsm I, and Taq I) and start codon (Fok I) polymorphisms on 1,25(OH)(2)D(3)-modulated IL-12p40, IFN-gamma, IL-10, and IL-5 response to live Mycobacterium tuberculosis and its culture filtrate antigen (CFA) in 60 normal healthy subjects and 51 pulmonary tuberculosis patients. In peripheral blood mononuclear cell cultures with CFA and 1,25(OH)(2)D(3), IL-12p40, and IFN-gamma levels were significantly decreased (p < 0.05) and IL-10 levels were significantly increased (p < 0.05) in patients with GG genotype. The extended genotype bbaaTT (baT haplotype) was associated with decreased IL-12p40 and IFN-gamma levels and significantly increased IL-10 levels (p < 0.05). The Cdx-2 GG genotype and baT haplotype are associated with a suppressed Th1 and increased IL-10 response, which suggests that 1,25(OH)(2)D(3) probably through the VDR polymorphic variants augments the anti-inflammatory response at the site of M. tuberculosis infection.  相似文献   

6.
The presence of certain vitamin D receptor (VDR) genotypes has been associated with low bone mineral density (BMD) in elderly populations as well as with accelerated bone loss in patients with rheumatoid arthritis (RA). In the present study, VDR genotypes from 120 Spanish patients with RA were investigated. Three VDR gene polymorphisms (BsmI, ApaI and TaqI) were investigated using polymerase chain reaction followed by enzymatic digestion. The distributions of VDR allelic frequencies were similar in patients and controls and therefore no influence of VDR polymorphisms on rheumatoid arthritis susceptibility could be demonstrated. However, in an analysis of the clinical features of the different VDR-related genetic subgroups, the BB/tt genotype, defined by the BsmI and TaqI restriction site polymorphisms, was identified to be weakly associated with an early onset RA in female patients. This VDR genotype has been associated with a low BMD level in various studies. When patients were stratified according to the presence of the shared HLA epitope SE, it was found that SE + female patients bearing the BB/tt genotype showed the earliest disease onset. The mechanisms by which the VDR polymorphism is associated with RA is unknown, but they could be related to the immunoregulatory properties of vitamin D.  相似文献   

7.
Osteoporosis (OP) is an important public issue affecting more than 150 millions all over the world, mainly post-menopausic women. Epidemiological studies have shown that the genetic factors could be involved in 80-90% of the bone mineral density variabiblity and therefore, related to the risk of OP manifestations. The vitamin D receptor (VRD) gene has been extensively studied, but its relationship with OP has been controversial. The aim of this investigation was to study the association of Bsm I, Apa I and Taq I VDR gene polymorphism with OP in 147 post-menopausic women; 71 with OP and 76 without the disease (control). The molecular gene analysis was performed using the polymerase chain reaction (PCR). The genotypes BB, AA, and tt were found in 56.33, 50.70 and 25.35% and in 21.05, 28.95 and 10.53% of OP patients and controls respectively. The haplotype BBAAtt was observed in 23.94% of OP patients and 5.26% of the controls. This haplotype was a risk factor for OP, since a odds ratio (OR) of 5.66 was found, while, haplotype BbaaTT was a protection factor (OR: 0.10). These findings support the association of the vitamin D receptor gene BBAAtt haplotype with OP.  相似文献   

8.
目的测定汉族人维生素D受体基因TruⅠ酶切位点多态性分布并探讨其对BsmⅠ酶切位点多态性分布测定的影响。方法收集80名健康汉族人外周静脉血标本,提取基因组DNA,用限制性片段多态性长度酶切法测定80名汉族人维生素D受体基因TruⅠ、BsmⅠ酶切位点多态性;换用常规引物再次测定上述标本BsmⅠ酶切位点多态性;分析维生素D受体基因TruⅠ、BsmⅠ酶切位点多态性及两次测定的BsmⅠ位点的一致性。结果测得TruⅠ基因型频率为TT68.7%,Tt26.3%,tt5.0%;同一PCR片段上测得BsmⅠ位点基因型频率为BB6.2%,Bb52.5%,bb41.3%,多态性分布均符合Hardy-Weinberg平衡;换用常规引物测定同批标本BsmⅠ位点多态性,基因型分布为BB20.0%,Bb26.2%,bb53.8%,不符合Hardy-Weinberg平衡(r=13.29,P〈0.01)。与第1次测定相比,有22个标本基因型由Bb型变成BB型或bb型,发生基因型丢失。结论汉族人VDR基因存在TruⅠ多态性,其多态性分布与其它种族不同;TruⅠ酶切位点多态性可引起BsmⅠ位点多态性测定时等位基因的丢失。  相似文献   

9.
《Human immunology》2016,77(6):498-505
Vitamin D receptor (VDR) gene variants have been shown to be regulating the immune response in tuberculosis. We studied the regulatory role of VDR promoter Cdx-2 and 3′UTR TaqI gene variants on chemokine levels from culture filtrate antigen (CFA) stimulated with or without 1,25(OH)2D3 treated peripheral blood mononuclear cells of 50 pulmonary tuberculosis patients (PTB) and 51 normal healthy controls (HCs). In CFA with 1,25(OH)2D3 treated cultures, the MIP-1α, MIP-1β, RANTES levels were significantly decreased in Cdx-2 AA genotype compared to GG genotype, while a significantly increased MIG level was observed in Cdx-2 AA genotype (p < 0.05). In TaqI polymorphism, tt genotype significantly decreased MIP-1β and RANTES levels compared to TT genotype. Moreover, a significantly increased level of IP-10 and MIG was observed in TaqI tt genotype compared with TT genotype (p < 0.05). The results suggests that the 1,25(OH)2D3 may alter the chemokine response through the VDR polymorphic variants during infection.  相似文献   

10.
目的:了解广州地区绝经后妇女维生素D受体基因多态性的分布,并进一步研究其与骨密度的关系。 方法:应用聚合酶链反应-限制性片段长度多态性(PCR-RFCP)等生物学技术检测203例绝经后广州地区妇女维生素D受体(VDR)基因型,同时用双能X线骨密度测量仪检测腰椎、股骨颈、瓦氏三角、大转子处骨密度(BMD)。 结果:203例受试对象中,VDR基因型分别为BB型17例(占8.3%)、Bb型60例(占29.6%),bb型126例(占62.1%), b等位基因频率为76.85%、B等位基因频率为23.05%,基因型分布符合Hardy-Weinberg定律。分析其基因型与骨密度的关系显示:只有bb与Bb、BB基因型在腰椎骨密度存在差异(P<0.05)、Bb与BB的腰椎BMD无差异(P>0.05),其余部位3种基因型骨密度无差异(P>0.05)。 结论: VDR基因型与BMD间存在着一定关联,但尚不能作为预测广州绝经后妇女发生骨质疏松危险性的遗传标志。  相似文献   

11.
OBJECTIVES: Osteoporosis is a common condition in postmenopausal women. Bone mineral density (BMD), the major determinant of osteoporotic fracture risk, has a particular genetic background. However, consensus on the association of BMD with specific gene locus has not been reached. The race and ethnicity specific divergence in association studies must be assessed to predict the susceptibility and therapeutic response of associated genes. We investigated the potential association of Vitamin D receptor (VDR) gene polymorphisms ApaI, BsmI, FokI and TaqI with BMD in 246 postmenopausal Indian women (average age 54.2+/-3.4 years). METHODS: The subjects were genotyped by PCR-RFLP and underwent BMD measurements at spine and hip by dual energy X-ray absorptiometery. RESULTS: The average BMD at spine and hip of women with genotypes aa, bb (presence of restriction sites for ApaI and BsmI), FF and TT (absence of restriction sites for FokI and TaqI) was more than 10% higher than those with genotypes AA, BB, ff and tt, respectively. The interaction between BsmI, ApaI and TaqI genotypes showed significant effect of BsmI-ApaI genotypes (p=0.052) in this combination on BMD. However, presence of T allele in combination showed positive influence on BMD. Within the group, genotypes BB, ff and tt were significantly prevalent in women with osteoporotic bone mass, tt and BB had significantly higher adjusted odd ratio (OR) for age more than 55years. CONCLUSION: Study reveals that VDR gene polymorphisms are associated with BMD in Indian women and perhaps, influence some determinant of bone metabolism. Ethnicity may attribute to frequency variation, however, allele impact remains same.  相似文献   

12.
Vitamin D receptor (VDR) genotypes have been shown to be associated with differential susceptibility or resistance to tuberculosis. The influence of FokI, BsmI, ApaI and TaqI variants of VDR gene on 1, 25(OH)2 D3 modulated granzyme A expression of cytotoxic lymphocytes induced by culture filtrate antigen (CFA) of Mycobacterium tuberculosis was studied in 40 pulmonary tuberculosis (PTB) patients and 49 normal healthy subjects (NHS) by flow cytometry. In both the study groups, addition of 1, 25(OH)2 D3 (10− 7M) significantly reduced the percentage of granzyme A positive cells in both unstimulated (NHS, p < 0.0001; PTB, p = 0.02) and stimulated culture conditions (CFA, NHS, p < 0.0001; PTB, p = 0.0001) which correlated positively with the IFN-γ levels (unstimulated, p = 0.01; CFA stimulated, p = 0.004) in NHS. The ApaI aa genotype and bbaaTT extended genotype were associated with a significantly decreased percentage of granzyme A positive cells in NHS (p < 0.05). Our results suggest that 1, 25(OH)2 D3 suppresses granzyme A probably by down-regulating Th1 cytokine response. Moreover, the VDR gene variants might regulate cytotoxic T-cell response via 1, 25(OH)2 D3 mediated suppression of granzyme A expression in tuberculosis.  相似文献   

13.
维生素D受体基因多态性与乳腺癌的相关性   总被引:2,自引:0,他引:2  
目的:研究维生素D受体基因的多态性与乳腺癌的关系。方法:收集86例乳腺癌患者及134名对照,用聚合酶链反应-限制性片段长度多态性方法,在维生素D受体基因的3’端分析了两个限制性酶切位点(ApaI及TaqI)的多态分布。结果:发现TaqI位点等位基因在两个群体间分布的差异有显著性(P=0.0004)。进一步对基因型进行分析发现,Tt、tt基因型与乳腺癌相关。而ApaI位点两等位基因未发现在两群体中存在差异。对ApaI及TaqI两座位的单体型进行分析,发现tA间存在连锁不平衡。在两群体中分析单体型的分布发现tA在病例中的比例明显高于对照人群,提示tA单体型与乳腺癌相关。两个位点等位基因及单体型与临床指标的分析均未发现阳性结果。结论:维生素D受体基因的多态怀与乳腺癌有关,提示维生素D受体基因与乳腺癌有关。  相似文献   

14.
OBJECTIVE: Vitamin D has been shown to exert multiple immunomodulatory effects and is known to suppress T-cell activation by binding to the vitamin D receptor (VDR). To determine whether VDR gene polymorphisms are related to the susceptibility to celiac disease, we investigated its implication as a candidate gene in the Basque population. Because celiac disease and type 1 diabetes share common susceptibility loci, we also analyzed families with type 1 diabetes mellitus. METHODS: A total of 37 families with celiac disease and 64 type 1 diabetic families of Basque origin with at least one affected offspring were genotyped for four VDR restriction-site polymorphisms (Fok I, Bsm I, Apa I and Taq I). The AFBAC approach was used to test for association. RESULTS: Comparison of VDR genotypes of the patients with those of 88 healthy individuals identified "ff" as a risk genotype for celiac disease [p = 0.01; OR = 3.45 (1.12-10.79)]. On the other hand, a significantly higher frequency of haplotype "fBAt" was observed in the type 1 diabetic group [p(c) = 0.02; OR = 4.4 (1.5-15.3)]. CONCLUSION: Our findings suggest that polymorphisms within the vitamin D receptor gene are markers of susceptibility to or protection from autoimmune diseases, although, at least in the Basque population, association of VDR variants with celiac disease and type 1 diabetes seems to be heterogeneous.  相似文献   

15.
16.
Among genes implied on the osteoporosis genetics, the most studied gene worldwide is the receptor gene of D vitamin (VDR), through the characterization of Bsm I polymorphism. The main objective of this research was to analyze the Bsm I polymorphism of the VDR gene in a sample of 133 postmenopausal women distributed in three groups: 54 with osteoporosis, 24 with osteopenia and 55 normal controls for the disease. 28 of the women with osteoporosis presented the BB genotype, which is related in other countries to bone mineral density decrease, 20 had the Bb genotype, and 6 the bb genotype. Of the control group only 11 women presented the BB genotype, 36 showed the heterozygote genotype and 8 the bb genotype. The frequencies of the B and b alleles in the analyzed population were 0.6 and 0.4 respectively. The BB genotype was found in 52% of the group with osteoporosis, and in 20% of the control group, these findings are statistically significant, which suggest an association between the BB genotype and osteoporosis.  相似文献   

17.
Since bone mineral density may be influenced by the polymorphisms of the vitamin D receptor (VDR) gene, we studied whether VDR genotypes might drive the progression toward hyperparathyroidism or hypoparathyroidism in patients with end-stage renal disease. On the basis of their parathyroid hormone (PTH) levels, we divided 99 patients undergoing dialysis into 2 groups: 56 patients with hypoparathyroidism (PTH < 104 pg/mL [< 11 pmol/L]) and 43 with hyperparathyroidism (PTH > 261 pg/mL [> 27.5 pmol/L]). The BB polymorphism was more frequent in patients with hypoparathyroidism (34%) than in patients with hyperparathyroidism (16%), but the difference did not reach statistical significance. Patients with the B allele and BB genotype had a significantly lower dialytic age and serum PTH and alkaline phosphatase levels than patients with the b allele and bb genotype. These results suggest that in end-stage renal disease, the BB genotype may mark a higher risk of developing hypoparathyroidism and diminished bone turnover.  相似文献   

18.
Ultraviolet radiation (UVR) exposure may protect against prostate cancer development via a mechanism involving vitamin D. The vitamin D receptor (VDR) gene is therefore a candidate susceptibility factor for prostate cancer. This possibility has been previously investigated with conflicting results. We examined the association of VDR genotypes (variants at the CDX-2, Fok1, and Taq1 sites), haplotypes, and genotype combinations with risk by studying 368 prostate cancer and 243 benign prostatic hypertrophy (BPH) patients. CDX-2, Fok1, and Taq1 genotype and haplotype frequencies were not significantly different in cancer and BPH patients. As the impact of VDR polymorphisms may depend on UVR exposure, we studied associations of variants with risk in men stratified into low (below median) and high (above median) cumulative exposure/year groups. In men with UVR exposure above the median (1,100 hr/year), CDX-2 GA and AA (odds ratios [OR] = 2.11 and 2.02, respectively) and Fok1 ff (OR = 2.91) were associated with increased prostate cancer risk. No associations were observed for Taq1 genotypes. Of the genotype combinations, relative to all other CDX-2 and Taq1 and combinations, GGTT (P = 0.022, OR = 0.30), and relative to all other Fok1 and Taq1 combinations, FFTT (P = 0.026, OR = 0.35) were associated with reduced prostate cancer risk in the presence of the main effects. None of the other two- or three-genotype combinations was associated with risk. These data indicate that VDR variants influence prostate cancer risk and that this association is dependent on the extent of UVR exposure.  相似文献   

19.
目的:探讨在重庆市区生活10年以上的汉族绝经妇女骨质疏松症与维生素D受体基因多态性的关系。方法:用聚合酶链反应-限制性片段长度多态性技术检测了40例绝经后患骨质疏松症的妇女和21名同龄绝经后无骨质疏松症的妇女的维生素D受体基因多态性。结果:骨质疏松组维生素D受体基因型bb、Bb、BB频率分别为82.5%、17.5%及0,无骨质疏松组分别为85.71%、14.29%及0,两组差异无显著性(P>0.05)。结论:就目前调查例数看,重庆地区汉族妇女骨质疏松与BB基因型无明显相关性。  相似文献   

20.
阿昌族与汉族维生素D受体基因FokⅠ多态性   总被引:4,自引:1,他引:4  
目的 了解维生素D受体基因多态性在中国不同民族中的分布。方法 应用聚合酶链反应一限制性片段长度多态性分析、基因测序等技术检测68名阿昌族人和92名汉族人的维生素D受体基因Fok Ⅰ多态性,比较两组维生素D受体基因型和等位基因的分布频率。结果在68名阿昌族人中FF基因型占18%、Ff基因型占35%、ff基因型占47%,而在92名汉族人中FF基因型占22%、Ff基因型占52%、ff基因型占26%。两组维生素D受体基因型的分布频率差异有显著性(x^2=7.716,P=0.021)。结论 阿昌族与汉族维生素D受体基因Fok Ⅰ多态性分布频率差异有显著性。  相似文献   

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