抗菌肽LL37在银屑病发病机制中的研究现状

银屑病是一种常见的慢性炎症性皮肤病,与自身反应性T细胞的局部活化及表皮角质形成细胞的异常增殖分化密切相关.银屑病患者皮损中含有大量免疫活性物质,包括多种细胞因子、趋化因子以及抗菌肽LL37等.正常情况下,细胞凋亡产生的少量DNA/RNA可被自身降解,并不引起炎症反应,但角质形成细胞的过度增殖活化,可在皮损局部产生大量自体DNA及RNA.LL37可以破坏机体对自身DNA/RNA的天然免疫耐受,并与之结合形成免疫复合物.该复合物运送至浆细胞样树突细胞早期内体单元中,在Toll样受体的介导下,浆细胞样树突细胞产生大量干扰素-α,而干扰素-α是银屑病中的关键性炎症因子,可以导致银屑病的发病与持续.     

红斑、丘疹及鳞屑性皮肤病

20130125银屑病患者皮损和外周血中CD123+BD-CA-2+浆细胞样树突细胞的表达/陈静(河南省人民医院皮肤科),王豫平,李家文…∥中华皮肤科杂志.-2012,45(7).-478～480收集22例寻常性银屑病、15例健康人皮肤组织和外周血,免疫组化检测患者皮损和健康人组织中浆细     

树突细胞在特应性皮炎发病中的研究进展

特应性皮炎是一种慢性复发性炎症性皮肤病,具有血清IgE水平升高、Th2型免疫过度反应以及对多种病原微生物易感性增加等特点.研究表明,朗格汉斯细胞和表皮炎症样树突细胞是在特应性皮炎皮损中出现的两种树突细胞.其中表皮炎症样树突细胞是炎症性皮肤病所特有的一种树突细胞,仅在炎症性皮肤中表达,被激活后可释放大量炎症因子和趋化因子,而在皮炎得到成功控制后逐步消失.在特应性皮炎的病理生理机制中,表皮炎症样树突细胞不仅在炎症的持续和发展中起着重要作用,还可能与皮损局部Th2反应向Thl反应漂移有关.     

抑制树突细胞MMP-13基因对咪喹莫特诱导的小鼠银屑病样炎症模型的影响

目的：明确抑制树突细胞MMP-13基因对咪喹莫特诱导的小鼠银屑病样炎症模型的影响。方法：构建树突细胞MMP-13基因特异性敲除的小鼠模型（MMP-13^LOX/LOX）,应用咪喹莫特诱导小鼠银屑病样皮损的发生。将小鼠分为野生型对照组、MMP-13^LOX/LOX对照组、咪喹莫特诱导的野生型实验组和咪喹莫特诱导的MMP-13^LOX/LOX实验组,分析不同组别小鼠皮损临床表现并记录PASI评分,检测各组小鼠皮损中IL-1β、IL-6、IL-23和IL-17A表达。结果：与咪喹莫特诱导的野生型实验组小鼠比较,咪喹莫特诱导的MMP-13^LOX/LOX实验组银屑病皮损表现相比更加温和,仅有轻度的棘层肥厚和真皮细胞浸润,皮损中IL-1β、IL-6表达下调,而IL-23和IL-17A表达无明显改变。结论：抑制树突细胞MMP-13基因可降低炎症因子IL-6、IL-1β的表达及减弱小鼠皮肤银屑病炎症反应。     

抗菌肽LL-37在银屑病发病机制中的作用

银屑病是一种以T淋巴细胞异常活化和浸润为主要特征的慢性炎性反应皮肤病。抗菌肽LL-37的表达在银屑病的发病机制中可能处于上游地位,并成为新的治疗靶标。LL-37过度表达可导致浆细胞样树突状细胞异常活化,并激活Th1,Th17细胞与角质形成细胞间的循环刺激网络,是银屑病皮损炎症反应持续存在的重要基础。     

银屑病患者皮损和外周血中CD123+BDCA-2+ 浆细胞样树突细胞的表达

目的 探讨CD123+BDCA-2+浆细胞样树突细胞（PDC）在寻常性银屑病患者皮损和外周血中的表达及意义。方法 收集22例寻常性银屑病患者和15例健康人皮肤组织和外周血,免疫组化法检测患者皮损和健康人皮肤组织中PDC的表达水平,流式细胞仪检测外周血中PDC的比例。结果 免疫组化结果显示,银屑病皮损中PDC的表达水平为（10.1 ± 2.1）/mm2,健康对照组为（0.4 ± 0.6） /mm2,银屑病组显著高于健康对照组（t = 17.34,P < 0.01）。银屑病患者外周血中CD123+BDCA-2+PDC占外周血单一核细胞的比例为（0.17 ± 0.07）%,健康对照组为（0.33 ± 0.20）%,银屑病组显著低于健康对照组（t = 4.48,P < 0.01）。结论 PDC通过在皮损中重新分布,在银屑病外周血中下降,可能与银屑病的发生、发展相关。     

母细胞性浆细胞样树突细胞肿瘤

报告1例母细胞性浆细胞样树突细胞肿瘤。患者女,26岁。面部结节、斑块半年。皮肤科检查:右颧部可见约4 cm×6 cm暗红色浸润性斑块,类圆形分叶状,境界清楚,皮损中央破溃。皮损组织病理检查:真皮全层及皮下脂肪间见较多致密的异形淋巴细胞浸润,细胞中等大小,核膜薄,染色质细,核分裂象易见。免疫组化:CD4(+)、CD56(+)、CD123(+)、CD43(+)、CD34(+),Ki-67(60%阳性);CD20、CD79a、丝氨酸蛋白酶(granzyme)B、CD3、CD45RO、CD68、末端脱氧核苷酸转移酶(TDT)、髓过氧化物酶(MPO)、T细胞内抗原(TIA)-1均阴性。诊断:母细胞性浆细胞样树突细胞肿瘤。     

自行消退的皮肤母细胞性浆细胞样树突细胞肿瘤

报告1例皮肤母细胞性浆细胞样树突细胞肿瘤。患者女,33岁,孕32+1周。全身多发紫红色结节及斑块1个月,无痛痒,外周血WBC及单核细胞均增多。皮肤科检查:躯干及四肢散在紫红色结节及斑块,表面光滑,质韧。皮损组织病理检查:真皮全层胶原束间单个核细胞浸润,可见核异形。骨髓穿刺示骨髓增生Ⅱ级,粒系0.27,红系0.29,单核细胞比例偏高,原幼单细胞占0.31,可见Auer小体。外周血涂片:单核细胞比例偏高,可见中幼粒细胞。免疫组化示CD56(+)及CD4部分(+)。诊断:皮肤母细胞性浆细胞样树突细胞肿瘤。患者未行任何治疗,剖宫产后皮损、血象及骨髓象均暂时好转。3个月后病情复发,进展为急性单核细胞白血病。血液科行CLAG方案化疗达到完全缓解。     

银屑病患者皮损中浆细胞样树突细胞和Toll样受体9、干扰素调节因子7及干扰素αmRNA的表达

浆细胞样树突细胞(plasmaeytoid dendritic cells,pDC)是最近发现的具有特征性的树突细胞(dendritie cell,DC)的一个亚类,来源于淋巴样前体DC,有浆细胞样形态,CD123为其特征性表面标记^[1],是最强大的干扰素α(IFN-α)产生细胞^[2],而干扰素调节因子7(IFN regulatory factor 7,IRF-7)是IFN-α基因的主要诱导和活化者^[3].pDC产生IFN-α依赖于Toll样受体9(TLR9)^[4].为了探讨它们在银屑病发病中的作用,我们采用免疫组织化学方法和逆转录-聚合酶链反应(RT-PCR),对寻常性银屑病患者皮损中的pDC,TLR9、IRF-7和IFN-α mRNA进行了检测.     

树突细胞成熟分化状态在炎症性皮肤病中作用机制的研究进展

树突细胞作为最主要的抗原提呈细胞,是连接固有免疫和适应性免疫的桥梁.树突细胞具有激活免疫应答和诱导免疫耐受的双重功能,其发挥免疫调节作用的功能与其所处的发育阶段及表型变化有着密切的关系.未成熟树突细胞具有较强的抗原摄取、处理及加工能力,抗原提呈能力弱,倾向于诱导机体免疫耐受;成熟树突细胞抗原提呈能力增强,可活化T、B淋巴细胞,倾向于激活免疫应答.髓系树突细胞主要启动和参与细胞免疫应答;而浆细胞样树突细胞则主要与体液免疫应答有关.目前认为,树突细胞成熟状态及表型变化在感染、肿瘤、自身免疫性疾病的发生发展中起着关键的作用.     

New fillers for the new man

ABSTRACT:  Two new collagen-based lidocaine-containing dermal fillers, ArteSense™/ArteFill™ (Artes Medical, San Diego, CA) and Evolence® (Colbar LifeScience Ltd., Herzliya, Israel), have proved to be of particular interest to men, many of whom seek a long-lasting or permanent correction. ArteFill™ has been available in the United States since 2006, and it is expected that Evolence® will reach the American market in 2008. The properties of the two products will be described, and experience based on the administration of many hundreds of syringes of both products by a Canadian dermatologist will be detailed here, with tips and precautions to optimize patient outcomes.     

Outcomes and adverse effects of ablative vs nonablative lasers for skin resurfacing: A systematic review of 1093 patients

It is generally believed that ablative laser therapies result in prolonged healing and greater adverse events when compared with nonablative lasers for skin resurfacing. To evaluate the efficacy of ablative laser use for skin resurfacing and adverse events as a consequence of treatment in comparison to other modalities, a PRISMA‐compliant systematic review (Systematic Review Registration Number: 204016) of twelve electronic databases was conducted for the terms “ablative laser” and “skin resurfacing” from March 2002 until July 2020. Studies included meta‐analyses, randomized control trials, cohort studies, and case reports to facilitate evaluation of the data. All articles were evaluated for bias. The search strategy produced 34 studies. Of 1093 patients included in the studies of interest, adverse events were reported in a total of 106 patients (9.7%). Higher rates of adverse events were described in nonablative therapies (12.2% ± 2.19%, 31 events) when compared with ablative therapy (8.28% ± 2.46%, 81 events). 147 patients (13.4%) reported no side effects, 68 (6.22%) reported expected, transient self‐resolving events, and five (0.046%) presented with hypertrophic scarring. Excluding transient events, ablative lasers had fewer complications overall when compared with nonablative lasers (2.56% ± 2.19% vs 7.48% ± 3.29%). This systematic review suggests ablative laser use for skin resurfacing is a safe and effective modality to treat a range of pathologies from photodamage and acne scars to hidradenitis suppurativa and posttraumatic scarring from basal cell carcinoma excision. Further studies are needed, but these results suggest that ablative lasers are a superior, safe, and effective modality to treat damaged skin.     

Genetic alterations in RAS‐regulated pathway in acral lentiginous melanoma

Studies integrating clinicopathological and genetic features have revealed distinct patterns of genomic aberrations in Melanoma. Distributions of BRAF or NRAS mutations and gains of several oncogenes differ among melanoma subgroups, while 9p21 deletions are found in all melanoma subtypes. In the study, status of genes involved in cell cycle progression and apoptosis was evaluated in a panel of 17 frozen primary acral melanomas. NRAS mutations were found in 17% of the tumors. In contrast, BRAF mutations were not found. Gains of AURKA gene (20q13.3) were detected in 37.5% of samples, gains of CCND1 gene (11q13) or TERT gene (5p15.33) in 31.2% and gains of NRAS gene (1p13.2) in 25%. Alterations in 9p21 were identified in 69% of tumors. Gains of 11q13 and 20q13 were mutually exclusive, and 1p13.2 gain was associated with 5p15.33. Our findings showed that alterations in RAS‐related pathways are present in 87.5% of acral lentiginous melanomas.     

Self‐resolving superficial primary cutaneous mucormycosis in a 7‐week‐old infant

A 7‐week‐old girl, born at 30 weeks' gestational age, presented to clinic for evaluation of a crop of vesicular lesions that were noted after removal of a bandage that had been in place for 4 days. A punch biopsy of the lesion revealed fungal elements that were later identified as Rhizopus spp. The lesion began to self‐resolve, and no further treatment was needed, with full resolution of the lesion by 1 month after presentation. Clinicians should be aware of the variable presentations of mucormycosis and consider fungal infection in the differential diagnosis when evaluating vulnerable patients with skin eruptions.     

Pathogenic role of IL-17 in psoriasis and psoriatic arthritis

Psoriasis is a chronic inflammatory skin disorder resulting from a complex network of cytokines and chemokines produced by various immune cell types and tissue cells. Emerging evidence suggests a central role of IL-17 and IL-23/T17 axis in the pathogenesis of psoriasis, giving a rationale for using IL-17-blocking agents as therapeutics.Three agents targeting IL-17 signaling are being studied in Phase III clinical trials: secukinumab and ixekizumab (IL-17 neutralizing agents), and brodalumab (IL-17 receptor antagonist). Preliminary results are highly promising for all anti-IL17 agents, creating fair expectations on this class of agents as the new effective therapeutic approach for the treatment of psoriasis.