Jadeja Shahnawaz D, Mansuri Mohmmad Shoab, Singh Mala, Dwivedi Mitesh, Laddha Naresh C, Begum Rasheedunnisa
Department of Biochemistry, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara, Gujarat, India.
PLoS One. 2017 Jul 10;12(7):e0180958. doi: 10.1371/journal.pone.0180958. eCollection 2017.
Autoimmunity has been implicated in the destruction of melanocytes from vitiligo skin. Major histocompatibility complex (MHC) class-II linked genes proteasome subunit beta 8 (PSMB8) and transporter associated with antigen processing 1 (TAP1), involved in antigen processing and presentation have been reported to be associated with several autoimmune diseases including vitiligo.
To explore PSMB8 rs2071464 and TAP1 rs1135216 single nucleotide polymorphisms and to estimate the expression of PSMB8 and TAP1 in patients with vitiligo and unaffected controls from Gujarat.
PSMB8 rs2071464 polymorphism was genotyped using polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) and TAP1 rs1135216 polymorphism was genotyped by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) in 378 patients with vitiligo and 509 controls. Transcript levels of PSMB8 and TAP1 were measured in the PBMCs of 91 patients and 96 controls by using qPCR. Protein levels of PSMB8 were also determined by Western blot analysis.
The frequency of 'TT' genotype of PSMB8 polymorphism was significantly lowered in patients with generalized and active vitiligo (p = 0.019 and p = 0.005) as compared to controls suggesting its association with the activity of the disease. However, TAP1 polymorphism was not associated with vitiligo susceptibility. A significant decrease in expression of PSMB8 at both transcript level (p = 0.002) as well as protein level (p = 0.0460) was observed in vitiligo patients as compared to controls. No significant difference was observed between patients and controls for TAP1 transcripts (p = 0.553). Interestingly, individuals with the susceptible CC genotype of PSMB8 polymorphism showed significantly reduced PSMB8 transcript level as compared to that of CT and TT genotypes (p = 0.009 and p = 0.003 respectively).
PSMB8 rs2071464 was associated with generalized and active vitiligo from Gujarat whereas TAP1 rs1135216 showed no association. The down-regulation of PSMB8 in patients with risk genotype 'CC' advocates the vital role of PSMB8 in the autoimmune basis of vitiligo.
自身免疫被认为与白癜风皮肤中黑素细胞的破坏有关。据报道，参与抗原加工和呈递的主要组织相容性复合体（MHC）II类连锁基因蛋白酶体亚基β8（PSMB8）和抗原加工相关转运体1（TAP1）与包括白癜风在内的多种自身免疫性疾病有关。
探究PSMB8 rs2071464和TAP1 rs1135216单核苷酸多态性，并评估古吉拉特邦白癜风患者和未受影响对照中PSMB8和TAP1的表达。
采用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）对378例白癜风患者和509例对照进行PSMB8 rs2071464多态性基因分型，采用扩增阻滞突变系统-聚合酶链反应（ARMS-PCR）对TAP1 rs1135216多态性进行基因分型。通过qPCR检测91例患者和96例对照外周血单个核细胞（PBMC）中PSMB8和TAP1的转录水平。通过蛋白质印迹分析测定PSMB8的蛋白质水平。
与对照相比，泛发型和活动期白癜风患者中PSMB8多态性“TT”基因型的频率显著降低（p = 0.019和p = 0.005），表明其与疾病活动有关。然而，TAP1多态性与白癜风易感性无关。与对照相比，白癜风患者中PSMB8在转录水平（p = 0.002）和蛋白质水平（p = 0.0460）均显著降低。患者和对照之间TAP1转录本无显著差异（p = 0.553）。有趣的是，与CT和TT基因型相比，PSMB8多态性易感CC基因型个体的PSMB8转录水平显著降低（分别为p = 0.009和p = 0.003）。
PSMB8 rs2071464与古吉拉特邦泛发型和活动期白癜风有关，而TAP1 rs1135216无相关性。风险基因型“CC”患者中PSMB8的下调表明PSMB8在白癜风自身免疫基础中起重要作用。
