Are Podoplanin Gene Polymorphisms Associated with Atopic Dermatitis in Koreans?

Background

The histologic characteristics of atopic dermatitis (AD) include perivascular edema and dilated tortuous vessels in the papillary dermis. A single nucleotide polymorphism (SNP) of the fms-related tyrosine kinase 4 (FLT4) gene is associated with AD.

Objective

To investigate the associations between podoplanin (PDPN) gene SNPs and AD.

Methods

We genotyped 9 SNPs from 5 genes of 1,119 subjects (646 AD patients and 473 controls). We determined the promoter activity of 1 SNP (rs355022) by luciferase assay; this SNP was further investigated using 1,133 independent samples (441 AD patients and 692 controls).

Results

The rs355022 and rs425187 SNPs and the C-A haplotype in the PDPN gene were significantly associated with intrinsic AD in the initial experiment. The rs355022 SNP significantly affected promoter activity in the luciferase assay. However, these results were not replicated in the replication study.

Conclusion

Two SNPs and the C-A haplotype in the PDPN gene are significantly associated with intrinsic AD; although, the results were confirmed by luciferase assay, they could not be replicated with independent samples. Nevertheless, further replication experiments should be performed in future studies.     

Irradiation of light emitting diode at 850nm inhibits T cell-induced cytokine expression

Background

An anti-inflammatory effect of light obtained from light-emitting diodes (LEDs) has been discovered, however, limited ranges of wavelengths have been used and the action mechanism has been rarely demonstrated.

Objective

We sought to analyze the immunomodulatory effect of LED on Jurkat T cells and human T cells.

Methods

Jurkat T cells with/without stimulation were irradiated once or five times using seven ranges of LED wavelengths, from 415 nm to 940 nm. Cytotoxic effects were examined by an MTT assay. Changes in T cell-induced cytokines, including IL-2, IL-4, IL-10, IL-12 and IFN-gamma, and their upstream signaling molecules, ZAP-70 and PKCθ, were examined by real-time PCR, ELISA, and Western blot analysis. The effect of the LED wavelength, whose effect was identified on Jurkat T cells, was also examined in human CD3+ T cells with/without stimulation and in Dermatophagoides farinae-induced atopic dermatitis (AD) NC/Nga mice.

Results

Lower doses of LED irradiation at 850 nm inhibited T cell-derived cytokines without inducing cell death in both Jurkat T cells and human T cells. Repeated exposure resulted in a greater increase of inhibitory effects than that observed with a single exposure, and these effects were identified in the NC/Nga AD model.

Conclusions

Although more remains to be clarified, these results may support the clinical application of LED for immune regulation.     

Toll样受体9基因多态性与尖锐湿疣的研究

目的探讨Toll样受体9的单核苷酸多态性与尖锐湿疣(CA)发病的相关性.方法抽取63例CA患者和23例正常人对照组的外周静脉血,采用TLR9基因直接测序的方法分析TLR9受体的单核苷酸多态性.结果 TLR9基因自翻译起始点第1 174、1635、1269、1724位均存在单核苷酸多态性位点,分别称为SNP1、SNP2、SNP3和SNP4,其中SNP3、SNP4为新发现位点,SNP1、SNP2为NCBI数据库中公布的位点,登录号分别为rs352139、rs352140.CA患者与正常人对照组的SNP1位点的等位基因A的频率分别为0.690、0.609,等位基因G的频率0.309、0.391,两组间比较差异均无统计学意义(P>0.05).SNP2位点的等位基因A的频率分别为0.302、0.369,等位基因G的频率0.698、0.630,两组间比较差异无统计学意义(P>0.05).SNP1、SNP2两个多态性位点存在4种单倍体型,分别为AA、AG、GA、GG.每种单倍体型在CA患者组和正常人对照组间比较差异均无统计学意义(P>0.05).结论 TLR9基因在广东汉族人群中存在4个单核苷酸多态性位点,分别为SNP1、SNP2、SNP3、SNP4.SNP1、SNP2两位点与CA的发病易感性可能无相关性.     

Toll样受体9基因多态性与尖锐湿疣的研究

目的探讨Toll样受体9的单核苷酸多态性与尖锐湿疣(CA)发病的相关性.方法抽取63例CA患者和23例正常人对照组的外周静脉血,采用TLR9基因直接测序的方法分析TLR9受体的单核苷酸多态性.结果 TLR9基因自翻译起始点第1 174、1635、1269、1724位均存在单核苷酸多态性位点,分别称为SNP1、SNP2、SNP3和SNP4,其中SNP3、SNP4为新发现位点,SNP1、SNP2为NCBI数据库中公布的位点,登录号分别为rs352139、rs352140.CA患者与正常人对照组的SNP1位点的等位基因A的频率分别为0.690、0.609,等位基因G的频率0.309、0.391,两组间比较差异均无统计学意义(P>0.05).SNP2位点的等位基因A的频率分别为0.302、0.369,等位基因G的频率0.698、0.630,两组间比较差异无统计学意义(P>0.05).SNP1、SNP2两个多态性位点存在4种单倍体型,分别为AA、AG、GA、GG.每种单倍体型在CA患者组和正常人对照组间比较差异均无统计学意义(P>0.05).结论 TLR9基因在广东汉族人群中存在4个单核苷酸多态性位点,分别为SNP1、SNP2、SNP3、SNP4.SNP1、SNP2两位点与CA的发病易感性可能无相关性.     

Toll样受体9基因多态性与尖锐湿疣的研究

目的探讨Toll样受体9的单核苷酸多态性与尖锐湿疣(CA)发病的相关性.方法抽取63例CA患者和23例正常人对照组的外周静脉血,采用TLR9基因直接测序的方法分析TLR9受体的单核苷酸多态性.结果 TLR9基因自翻译起始点第1 174、1635、1269、1724位均存在单核苷酸多态性位点,分别称为SNP1、SNP2、SNP3和SNP4,其中SNP3、SNP4为新发现位点,SNP1、SNP2为NCBI数据库中公布的位点,登录号分别为rs352139、rs352140.CA患者与正常人对照组的SNP1位点的等位基因A的频率分别为0.690、0.609,等位基因G的频率0.309、0.391,两组间比较差异均无统计学意义(P>0.05).SNP2位点的等位基因A的频率分别为0.302、0.369,等位基因G的频率0.698、0.630,两组间比较差异无统计学意义(P>0.05).SNP1、SNP2两个多态性位点存在4种单倍体型,分别为AA、AG、GA、GG.每种单倍体型在CA患者组和正常人对照组间比较差异均无统计学意义(P>0.05).结论 TLR9基因在广东汉族人群中存在4个单核苷酸多态性位点,分别为SNP1、SNP2、SNP3、SNP4.SNP1、SNP2两位点与CA的发病易感性可能无相关性.     

Association of polymorphisms in genes encoding IL-4, IL-13 and their receptors with atopic dermatitis in a Korean population

Th2-dominated immune responses are believed to contribute to the pathogenesis of atopic dermatitis (AD). IL-4 and IL-13 are typical pleiotropic Th2 cytokines that play a central role in IgE-dependent inflammatory reactions. Single-nucleotide polymorphisms (SNPs) in IL-4 and IL-13 have been reported in patients with allergic disease from numerous countries. Gene-gene interactions among genes have been identified in patients with asthma, although negative results have been reported. To investigate the associations of SNPs in these genes and the interactions between these genes in AD, we genotyped 23 SNPs of the IL-4, IL-13, IL-4R, IL-13Rα1 and IL-13Rα2 genes for 1089 case-control samples (631 AD patients and 458 controls) and analysed the SNPs and haplotypes in these genes. We also searched for gene-gene interactions among these five genes. Our data identified an association between rs3091307 and rs20541 in the IL-13 gene and between rs2265753 and rs2254672 in the IL-13Rα1 gene and the AD phenotype. In particular, three of the four SNPs were especially predictive of the allergic type of AD (ADe), and the haplotype TCGG in the IL-13Rα1 gene showed significant association with AD, especially ADe. Furthermore, the combination of rs3091307 GG/ rs2265753 GG (IL-13/IL-13Rα1) conveyed a significantly higher risk for developing ADe. However, we did not identify any SNPs in the IL-4, IL-4R and IL-13Rα2 genes that were associated with AD. As IL-13Rα1 is most likely expressed in Th17 cells rather than in Th2 cells, these data suggest diversity in the classification of Th cells that needs to be verified in future studies.     

Podoplanin expression in wound and hyperproliferative psoriatic epidermis: regulation by TGF-β and STAT-3 activating cytokines, IFN-γ, IL-6, and IL-22

Background

Podoplanin (PDPN)/T1α/aggrus/PA2.26 antigen, a transmembranous glycoprotein, is a well-known lymphatic endothelial marker. Recent evidence indicates that PDPN is also expressed in keratinocytes especially of sebaceous glands.

Objective

To verify expression-pattern and the regulatory mechanism of PDPN in human epidermal keratinocytes.

Methods

PDPN-expression pattern was analyzed in normal and psoriatic epidermis by immunostaining. The regulatory mechanism of PDPN-expression of keratinocytes by cytokines was analyzed using specific inhibitors, siRNA, and adenoviral shRNA of signaling pathways.

Results

In normal skin, PDPN was expressed on the basal cell layer of sebaceous glands and on the outer root sheath of hair follicles. While no expression was detected in the normal interfollicular epidermis, PDPN was detected in the basal cell layer of wound and hyperproliferative psoriatic epidermis, where the granular layer is lacking. TGF-β1 and IFN-γ independently upregulated PDPN-expression of keratinocytes via TGF-β receptor-Smad pathway and JAK-STAT pathway, respectively. IL-6 and IL-22 also stimulated PDPN-expression of keratinocytes accompanied by STAT-3 phosphorylation. siRNA of STAT-1, inhibitors of STAT-3 signaling, AG490, STAT-3 inhibitor VI, and si/shRNA of STAT-3 inhibited the PDPN-expression of keratinocytes induced by IFN-γ, IL-6 and IL-22 but not by TGF-β1.

Conclusion

These results indicate that TGF-β1, IFN-γ, IL-6, and IL-22 induce PDPN-expression of keratinocytes, which might be significantly involved in the wound healing process as well as in the pathomechanism of hyperproliferative psoriatic epidermis.     

IL-33和IL1RL1基因单核苷酸多态性与特应性皮炎相关性研究

目的：分析IL-33和IL1RL1基因单核苷酸多态性(SNPs)与特应性皮炎（AD）的相关性。方法：PCR-SSP方法检测89例AD患者和138名正常对照组受试者IL-33和IL1RL1编码基因的等位基因和基因型频率。结果：AD患者的IL-33 rs1800925 C等位基因的频率高于对照组，而T等位基因和rs764706552等位基因G低于对照组（均P＜0.001）。IL-33 rs1800925基因型CC和rs764706552基因型CG与AD显著正相关（均P＜0.001）。两组患者的IL1RL1基因的等位基因和基因型频率无明显差异（均P＞0.05）。结论：IL-33基因可能与AD的发病相关。     

Raf kinase inhibitor protein expression correlates with differentiation but not with ERK phosphorylation in cutaneous squamous cell carcinoma

BackgroundThe acute skin lesions of atopic dermatitis (AD) are associated with Th2 cells; however, the chronic skin lesions of AD are associated with Th1 cells via the action of IL-12.ObjectiveWe evaluated the associations of single nucleotide polymorphisms (SNPs) and haplotype in the IL-12 and IL-12 receptor genes, and determined the gene–gene interactions between the SNPs of these genes and the SNPs of the IL-18 gene that we previously reported.MethodWe genotyped 24 SNPs from 4 IL-12/IL-12R genes for 1089 case–control samples (631 AD patients and 458 normal controls). We measured the serum IL-12 concentrations in 89 individuals (79 AD patients and 10 controls) by ELISA. We analyzed the SNPs and haplotypes in each gene and also searched for the gene–gene interactions.ResultThe rs582504 (IVS ? 798A/T) SNP and the haplotype TA (rs582054 and rs2243151) in the IL-12A gene, and the rs438421 (IVS12 + 1266T/C) SNP and the haplotype CCA (rs375947, rs438421, and rs1870063) in the IL-12RB1 gene were significantly associated with the AD phenotype. We showed that the rs438421 polymorphism in the IL-12RB1 (TT) gene and the rs2066446 polymorphism in the IL-12RB2 (AA) gene had a significant interaction to develop the ADe phenotype (allergic type of AD), and those individuals with the risk alleles, TT/AA/CC (IL-12RB1/IL-12RB2/IL-18), have more than a 10-fold increased risk to develop ADe.ConclusionThis study provides evidence for a significant interaction between the IL-12RB1 and IL-12RB2 genes that contribute to a 4-fold increased risk for developing ADe. In addition to the IL-12R interaction, we suggest that the IL-18 gene can significantly interact with the IL-12R gene to develop ADe. In addition to the interaction, the SNPs and haplotypes in the IL-12A and IL-12RB1 genes are independently and significantly associated with the AD phenotype, and especially with the ADe phenotype. This data may contribute to our understanding of AD genetic interactions and account for the additional risk of certain patients to develop AD.     

Toll样受体9基因多态性与尖锐湿疣的研究

目的 探讨Toll样受体9的单核苷酸多态性与尖锐湿疣（CA）发病的相关性。方法 抽取63例CA患者和23例正常人对照组的外周静脉血,采用TLR9基因直接测序的方法分析TLR9受体的单核苷酸多态性。结果 TLR9基因自翻译起始点第1174、1635、1269、1724位均存在单核苷酸多态性位点,分别称为SNP1、SNP2、SNP3和SNP4,其中SNP3、SNP4为新发现位点,SNP1、SNP2为NCBI数据库中公布的位点,登录号分别为rs352139、rs352140。CA患者与正常人对照组的SNP1位点的等位基因A的频率分别为0.690、0.609,等位基因G的频率0.309、0.391,两组间比较差异均无统计学意义（P ＞ 0.05）。SNP2位点的等位基因A的频率分别为0.302、0.369,等位基因G的频率0.698、0.630,两组间比较差异无统计学意义（P ＞ 0.05）。SNP1、SNP2两个多态性位点存在4种单倍体型,分别为AA、AG、GA、GG。每种单倍体型在CA患者组和正常人对照组间比较差异均无统计学意义（P ＞ 0.05）。结论 TLR9基因在广东汉族人群中存在4个单核苷酸多态性位点,分别为SNP1、SNP2、SNP3、SNP4。SNP1、SNP2两位点与CA的发病易感性可能无相关性。     

Differential expression of matrix metalloproteinases and proteoglycans in Juvenile Hyaline Fibromatosis

Background

Juvenile Hyaline Fibromatosis (JHF) is a rare autosomal recessive disorder, histologically characterized by the production and deposition of an unidentified hyaline material in the skin and other organs. Extracellular matrix molecules are implicated in the development of skin lesion which is debilitating and recurrent and, so far, no treatment is satisfactory.

Objective

To investigate the expression of matrix metalloproteinases (MMPs), their tissue inhibitors (TIMPs) and proteoglycans in lesional as compared to site-matched lesion-free skin tissue specimens of a JHF patient, aiming to elucidate the aetiopathological mechanisms involved in the development of JHF skin lesions.

Methods

Gelatinase activity of MMP-2 and MMP-9 was investigated by gelatine zymography. Protein levels of MMP-2, MMP-9, TIMP-1 and TIMP-2 in skin tissue extracts were measured by ELISA. Gene expression of MMPs, TIMPs and proteoglycans was examined by quantitative RT-PCR.

Results

JHF lesions exhibited significantly higher activity as well as elevated protein and gene expression of MMP-2 and MMP-9, as compared to lesion-free skin tissue specimens. Decorin was downregulated and aggrecan was upregulated in lesional skin, as compared to normal skin.

Conclusion

The results presented in this study indicate that MMPs and proteoglycans may be involved in the pathogenesis of JHF and therefore these molecules may offer alternative targets for pharmacological intervention to achieve more radical and effective treatment.     

Exclusion of CTSB and FDFT1 as positional and functional candidate genes for keratolytic winter erythema (KWE)

Background

Keratolytic winter erythema (KWE) or Oudtshoorn skin disease is a rare autosomal dominant monogenic disorder of epidermal keratinisation characterized clinically by cyclical peeling of the palms and soles. Due to a founder effect many KWE families have been identified in South Africa and the gene has been localized to 8p23.1-22, but the causal gene has yet to be identified.

Objective

To examine two compelling positional and functional candidate genes within the critical region on 8p: cathepsin B (CTSB), a lysosomal cysteine protease localized to pericellular spaces between keratinocytes, possibly playing a role in cell-cell adhesion; and farnesyl-diphosphate farnesyltransferase (FDFT1), a membrane-associated enzyme in cholesterol biosynthesis which, among its many functions, plays a role in barrier permeability and integrity.

Method

Mutation screening of the coding regions, 5′UTRs and intron/exon boundaries of CTSB and FDFT1 in genomic DNA and cDNA of patients affected with KWE. Relative gene expression profiles of CTSB and FDFT1 in palmoplantar skin biopsies were assessed by real-time RT-PCR.

Results

No DNA variants that segregate exclusively with KWE were identified. There was no significant difference in the CTSB expression profiles but a trend towards increased expression of FDFT1 was observed in the skin of affected individuals (p = 0.063). This observation prompted analysis of the FDFT1 promoter region; however, no genetic variants segregating with the KWE phenotype were observed and it is likely that the increased expression was triggered in response to skin inflammation and peeling.

Conclusion

CTSB and FDFT1 are excluded as candidates for KWE.     

Variants in MHC, LCE and IL12B have epistatic effects on psoriasis risk in Chinese population

Background

Psoriasis has long been considered as a complex disease, and gene-gene or gene-environment interactions may jointly influence the etiology for psoriasis.

Objective

We evaluated the associations of single nucleotide polymorphisms (SNPs) in MHC region, and determined the epistasis and combined effects of MHC locus and IL12B, LCE on risk for psoriasis.

Methods

We genotyped SNP rs1265181 (MHC) in 5067 cases and 6404 controls, combining with the prior GWAS data (1139 cases and 1132 controls), we explored the genetic interaction among MHC locus, LCE and IL12B by using logistic regression analysis. We evaluated the combined effects of MHC locus and two non-MHC loci in the combined sample of 6206 cases and 7536 controls.

Results

Extremely high significance of association was detected between rs1265181 and psoriasis (p combined <10E−300, OR = 16.52, 95% CI: 15.28-18.44). We observed significant interactions between MHC and LCE (p = 0.0016) and between MHC and IL12B (p = 0.0036). The risk increased some 26-fold in individuals with risk alleles in both MHC and LCE as compared with those without risk alleles, and individual carrying risk alleles of MHC and IL12B has around 36-fold higher risk of psoriasis than those with protective alleles.

Conclusions

This study provides evidence for the epistatic effects between MHC locus and LCE, IL12B genes. Besides, we suggest that MHC might be the main effect gene on the risk for psoriasis. This data may contribute to our understanding of psoriasis genetic interactions and account for the additional risk of certain patients to develop psoriasis.     

An environmental contaminant, benzo(a)pyrene, induces oxidative stress-mediated interleukin-8 production in human keratinocytes via the aryl hydrocarbon receptor signaling pathway

Background

Benzo(a)pyrene (BaP) is an environmental contaminant found in cigarette smoke. It is well known that cigarette smoking exacerbates interleukin-8 (IL-8)-related inflammatory skin diseases such as psoriasis, palmoplantar pustulosis and acne. Although BaP has been shown to exert its biological effects via the aryl hydrocarbon receptor (AhR) signaling pathway, the mechanism of its inflammatory effects on skin remains unanswered.

Objective

To elucidate whether or not BaP cause AhR activation and subsequent oxidative stress leading to IL-8 production in normal human epidermal keratinocytes (NHEKs).

Methods

NHEKs exposed to BaP were analyzed. Immunofluorescence, real-time PCR, Western blotting, ELISA, reactive oxygen species (ROS) detection using H2DCFDA and RNA interference using si (small interfering) RNA were employed.

Results

Immunofluorescence analysis clearly demonstrated that BaP induced nuclear translocation of AhR from cytoplasm. The AhR activation subsequently induced CYP1A1 mRNA and protein expression in a dose-dependent manner. In addition, ROS and IL-8 production were coordinately augmented by BaP, whereas this was not the case in IL-1α, IL-6, TNF-α or GM-CSF production. Knockdown of AhR expression using siRNA transfection inhibited BaP-induced-ROS and IL-8 production, suggesting that these responses are strongly dependent on the AhR signaling pathway. Furthermore, the addition of N-acetyl cystein or catalase cancelled the IL-8 production by BaP, indicating that ROS production is essential for IL-8 production.

Results

This data highlights AhR-ROS-dependent regulation of IL-8 in NHEKs by BaP, providing a plausible explanation, at least in part, for why cigarette smoking exacerbates IL-8-related skin diseases such as psoriasis, palmoplantar pustulosis and acne.     

IL-12B和IL-23R基因多态性与中国汉族人银屑病易感性关联研究

目的 探讨中国汉族人群中IL-12B和IL-23R基因多态性与银屑病易感性的关系。方法 在217例银屑病患者和288例正常人对照中,采用DNA直接测序法对IL-12B和IL-23R基因的多态性位点进行基因分型,并将阳性结果在一个更大的包括578例银屑病患者和1422例正常人对照的整合样本群中,使用Taqman探针荧光PCR技术进行重复检验。实验数据进行Hardy-Weinberg平衡检验、卡方检验、单倍型分析和Logistic回归模型分析。结果 IL-12B rs6887695位点等位基因频率在病例组与对照组之间差异有统计学意义,OR = 1.33（95% CI 1.03 ~ 1.73）,P = 0.028;IL-23R rs11465817和rs1343152位点等位基因频率在病例组与对照组之间差异无统计学意义（P > 0.05）。连锁不平衡分析发现,rs11465817和rs1343152位点之间有一定的连锁不平衡（D′ = 0.744,r2 = 0.281）。对2个位点进行单倍型分析发现,A-A ∶ OR = 2.890,P = 0.0018,提示这一单倍型具有显著的发病风险。结论 IL-12B基因rs6887695多态性与中国汉族人群银屑病易感性相关;IL-23R基因rs11465817、IL-23R基因rs1343152位点多态性与中国汉族人群银屑病易感性无显著相关性,但是,IL-23R基因rs11465817-rs1343152位点A-A单倍型的中国汉族人具有更高的银屑病发病风险。     

Oculocutaneous albinism type 3: a Japanese girl with novel mutations in TYRP1 gene

Background

Oculocutaneous albinism (OCA) type 3 caused by mutations of the TYRP1 gene is an autosomal recessive disorder of pigmentation characterized by reduced biosynthesis of melanin pigment in the skin, hair, and eye. The clinical phenotype has been reported as mild in Caucasian OCA3 patients.

Objective

We had the opportunity to examine a Japanese girl with OCA3 and investigated activity of TYRP1 protein derived from the mutant allele detected in the patient.

Methods

Mutation search for OCA responsible genes was done. A mutant allele with a missense mutation was analyzed using melanocyte cultures (b cells) established from a mouse model of OCA3.

Results

Compound heterozygous mutations, p.C30R and p.367fsX384, were detected in the Japanese girl. Then we revealed that the missense mutation, p.C30R, was functionally incapable of melanin synthesis with in vitro experiments.

Conclusion

This is the first report of the occurrence of OCA3 in Japanese population.     

Cathepsin K-upregulation in fibroblasts promotes matrigel invasive ability of squamous cell carcinoma cells via tumor-derived IL-1α

Background

Cathepsin K (CTSK), a cysteine protease with strong collagenolytic properties, is involved in extracellular matrix turnover. In the previous studies, CTSK expression was detected in peritumoral fibroblasts (Fbs) around squamous cell carcinoma (SCC), but not in those surrounding benign epidermal tumors. However, the mechanism governing CTSK expression in epidermal tumors remains unclear.

Objective

To study the regulatory mechanisms of fibroblastic CTSK expression in the SCC-stromal interaction.

Methods

We examined dynamic interactions of Fbs with tumorigenic SCC cells (A431 and A253) or normal human keratinocytes.

Results

SCC cells and normal keratinocytes did not synthesize CTSK, while Fbs constitutively expressed CTSK. When cocultured, SCC cells upregulated fibroblastic CTSK expression more potently than did normal keratinocytes, which was mainly attributable to SCC-derived IL-1α. Coculturing Fbs with SCC cells significantly augmented the matrigel invasive ability of SCC cells, which was downregulated when cocultured with CTSK knockdown Fbs or in the presence of neutralizing anti-IL-1α antibody.

Conclusion

The CTSK-upregulated Fbs generated by SCC-derived IL-1α may play a crucial role in the progression and invasion of SCC.