Interleukin-18 exacerbates skin inflammation and affects microabscesses and scale formation in a mouse model of imiquimod-induced psoriasis / 中华医学杂志(英文版)

BACKGROUND@#As a potent pro-inflammatory cytokine of the interleukin (IL)-1 family, IL-18 was elevated in early active and progressive plaque-type psoriatic lesions and that serum or plasma levels of IL-18 correlated with the Psoriasis Area and Severity Index (PASI). Although results from previous studies have established that IL-18 may aggravate psoriatic inflammation, the mechanisms of this process remain unknown. In this study, IL-18 knock out (KO) mice and wild-type (WT) mice were used to investigate the effects of IL-18 within a mouse model of psoriasis.@*METHODS@#WT and IL-18 KO mice were divided into four groups, including imiquimod (IMQ)-treated IL-18 KO group (n = 11) and WT group (n = 13) as well as their respectively gene-matched control mice (receiving vaseline; n = 12). PASI scores were used to evaluate psoriatic lesions in IMQ-treated mice. Pathological features and dermal cellular infiltration were investigated by hematoxylin and eosin staining. The levels of psoriasis-related cytokines including IL-23, IL-17, IL-12, IL-1β, IFNγ, IL-15, IL-27, and IL-4 were tested by real-time polymerase chain reaction (PCR). The protein level of IL-1β, IL-27, CXCL1, and Ly6 g were investigated by immunohistochemistry (IHC).@*RESULTS@#Acanthosis (98.46 ± 14.12 vs. 222.68 ± 71.10 μm, P < 0.01) and dermal cell infiltration (572.25 ± 47.45 vs. 762.47 ± 59.59 cells/field, P < 0.01) were significantly milder in IMQ-induced IL-18 KO mice compared with that in WT mice. IMQ-induced IL-18 KO mice manifested larger areas of Munro microabscesses (11,467.83 ± 5112.09 vs. 4093.19 ± 2591.88 μm, P < 0.01) and scales (100,935.24 ± 41,167.77 vs. 41,604.41 ± 14,184.10 μm, P < 0.01) as compared with WT mice. In skin lesions of IL-18 KO mice, the expressions of IL-1β, IL-4, and IL-27 were all significantly upregulated but IL-17 was decreased. Histologically, strong positive signals of Ly6g were observed within the epidermis of IL-18 KO mice but expressions of CXCL1 were decreased.@*CONCLUSIONS@#IL-18 may exacerbate prominent inflammation and influence pathological features in IMQ-induced mouse model of psoriasis. IL-18 may upregulate pro-inflammatory cytokines and reduce protective cytokines, thus aggravating psoriatic inflammation. In addition, IL-18 may be involved in the formation of Munro microabscesses and scales.

HighColonization and Impaired Permeability Barrier in Facial Seborrheic Dermatitis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Seborrheic dermatitis (SD) is a common inflammatory skin condition. The etiology is unclear, although overgrowth of Malassezia on the skin has been suggested to cause SD. This study investigated whether colonization with Staphylococcus plays a role in facial SD, which was not well addressed previously.</p><p><b>METHODS</b>The study was conducted from September 1, 2011 to February 20, 2012 in the First Hospital of China Medical University. In the first phase, the study evaluated the level of transepidermal water loss (TEWL) and the number of colony-forming units (CFU) of Staphylococcus in defined skin areas of SD patients who were human immunodeficiency virus (HIV) seropositive (HIV [+] SD [+] group, n = 13), classical SD (HIV [-] SD [+] group, n = 24) patients, HIV seropositive-non-SD (HIV [+] SD [-] group, n = 16) patients, and healthy volunteers (HIV [-] SD [-] group, n = 16). In the second phase, we enrolled another cohort of HIV (-) SD (+) patients who applied topical fusidic acid (n = 15), tacrolimus (n = 16), or moisturizer (n = 12). Changes in the Seborrheic Dermatitis Area Severity Index (SDASI), TEWL, and Staphylococcus density were evaluated 2 weeks later. Comparisons of each index were performed using analysis of variance (ANOVA) and least significant difference method.</p><p><b>RESULTS</b>The level of TEWL was greater through lesional sites in the HIV (+) SD (+) group than that in HIV (+) SD (-) and HIV (-) SD (-) groups (95% confidence interval [CI]: 18.873-47.071, P < 0.001 and 95% CI: 28.755-55.936, P < 0.001, respectively). The number of CFU of Staphylococcus was greater in the HIV (+) SD (+) group than that in HIV (+) SD (-) and HIV (-) SD (-) groups (95% CI: 37.487-142.744, P = 0.001 and 95% CI: 54.936-156.400, P < 0.001, respectively). TEWL was significantly more improved in patients treated with tacrolimus and fusidic acid than that in those treated with moisturizers (95% CI: 7.560-38.987, P = 0.004 and 95% CI: 4.659-37.619, P = 0.011, respectively). Topical tacrolimus and fusidic acid were significantly associated with decreased SDASI as compared with moisturizer (95% CI: 0.03-0.432, P = 0.025 and 95% CI: 0.033-0.44, P = 0.024, respectively).</p><p><b>CONCLUSIONS</b>High colonization with Staphylococcus epidermidis, along with impaired skin permeability barrier function, contributes to the occurrence of SD.</p>

T Helper 1 and T Helper 2 Cytokines Differentially Modulate Expression of Filaggrin and its Processing Proteases in Human Keratinocytes / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Atopic dermatitis (AD) is characterized by defective skin barrier and imbalance in T helper 1/T helper 2 (Th1/Th2) cytokine expression. Filaggrin (FLG) is the key protein to maintaining skin barrier function. Recent studies indicated that Th1/Th2 cytokines influence FLG expression in keratinocytes. However, the role of Th1/Th2 cytokines on FLG processing is not substantially documented. Our aim was to investigate the impact of Th1/Th2 cytokines on FLG processing.</p><p><b>METHODS</b>HaCaT cells and normal human keratinocytes were cultured in low and high calcium media and stimulated by either interleukin (IL)-4, 13 or interferon-γ (IFN-γ). FLG, its major processing proteases and key protease inhibitor lymphoepithelial Kazal-type-related inhibitor (LEKTI) were measured by both real-time quantitative polymerase chain reaction and Western blotting. Their expression was also evaluated in acute and chronic AD lesions by immunohistochemistry.</p><p><b>RESULTS</b>IL-4/13 significantly reduced, while IFN-γ significantly up-regulated FLG expression. IL-4/13 significantly increased, whereas IFN-γ significantly decreased the expression of kallikreins 5 and 7, matriptase and channel-activating serine protease 1. On the contrary, IL-4/13 significantly decreased, while IFN-γ increased the expression of LEKTI and caspase-14. Similar trends were observed in AD lesions.</p><p><b>CONCLUSIONS</b>Our results suggested that Th1/Th2 cytokines differentially regulated the expression of major FLG processing enzymes. The imbalance between Th1 and Th2 polarized immune response seems to extend to FLG homeostasis, through the network of FLG processing enzymes.</p>

Temporal effect of local hyperthermia on murine contact hypersensitivity / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The sensitization and elicitation phases are involved in the immunopathogenesis of contact hypersensitivity (CHS). Langerhans cells (LCs) are believed to play pivotal roles in the sensitization stage of CHS. Local hyperthermia on skin induces the migration as well as maturation of epidermal LCs. Although fever-range whole body hyperthermia and local hyperthermia at 43°C prior to sensitization were reported to suppress CHS, the effects of different temperatures and the timing sequence of local hyperthermia on CHS have not been tackled.</p><p><b>METHODS</b>Local hyperthermia was applied to murine dorsal skin 3 days prior to, concurrent with, or 2 days post sensitization with fluorescein isothiocyanate (FITC) in BALB/c mice. Local hyperthermia temperatures at 37°C, 39°C, 41°C and 43°C were applied to mouse dorsal skin and the severity of CHS was calculated by measuring the swelling response of the challenged ears.</p><p><b>RESULTS</b>Local hyperthermia at 39°C, 41°C and 43°C prior to sensitization reduced the severity of CHS, as compared with that at 37°C. The suppression of CHS was temperature dependent in that higher temperature had a stronger effect. On the contrary, the hyperthermia treatments, either concurrent with or post-sensitization, resulted in an enhanced temperature-dependent ear swelling response.</p><p><b>CONCLUSIONS</b>The severity of murine CHS could be influenced by local hyperthermia at the sensitization stage in a temperature dependent manner. The temporal effect of local hyperthermia suggested a novel factor in interpreting the severity of allergic contact dermatitis.</p>

Effects of local hyperthermia on maturation of Langerhans cells in HPV-infected skin / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigate the possible mechanism of local hyperthermia in the treatment of warts through detecting the differences in CD1a/CD83 of Langerhans cells (LCs) in émigrés from HPV-infected skin, as compared to normal skin.</p><p><b>METHODS</b>Confocal microscopy were performed on Condyloma Accuminatum (CA)and normal skin; Freshly taken biopsies of CA and normal skin were subjected to surface heating at 37 degrees C, 42 degrees C and 45 degrees C respectively, for 30 mins. Flow cytometry was used to determine the CD1a/ CD83 changes of LCs in émigrés from CA and normal skin.</p><p><b>RESULTS</b>By confocal microscopic observation, there were practically no CD1a+ LCs that expressed CD83 in the epidermis of both normal skin and CA. The proportions of CD1a+/CD83 LCs were significantly increased with increased temperatures in émigrés from both normal skin and CA. At each given temperature, the numbers of LCs in émigrés from CA were greater than those from normal skin.</p><p><b>CONCLUSION</b>Local hyperthermia can promote migration and maturation of LCs in HPV-infected skin and accordingly stimulate the immune system to treat warts.</p>

Regulation of haptoglobin expression in a human keratinocyte cell line HaCaT by inflammatory cytokines and dexamethasone / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Haptoglobin (Hp) is one of the acute-phase proteins. Recent studies have demonstrated that Hp exerts immunoregulatory and anti-inflammatory actions and may be one of the inhibitory factors of immune reactions in the skin. In this study we investigated the regulation of Hp expression in a human keratinocyte cell line HaCaT by various cytokines and glucocorticoid.</p><p><b>METHODS</b>HaCaT cells were cultured with IL-6 (50 ng/ml), TNF-alpha (20 ng/ml), IFN-gamma (20 ng/ml) or IL-4 (20 ng/ml) with or without 1 micromol/L dexamethasone in 6-well plates for 12, 24 and 48 hours. Both the cells and the supernatants were collected to detect the changes of Hp expression by reverse-transcription PCR, ELISA and immunohistochemistry.</p><p><b>RESULTS</b>The results showed that Hp expression were elevated at both the mRNA and protein level by the combination of IL-6, TNF-alpha or IL-4 with dexamethasone, whereas the three cytokines alone did not upregulate the Hp expression. IFN-gamma showed no effect on the Hp expression in HaCaT cells.</p><p><b>CONCLUSIONS</b>These findings suggest that different inflammatory cytokines as well as glucocorticoid may be involved in the regulation of Hp expression in keratinocytes, and this may be one of the negative feedback mechanisms in inflammatory skin diseases.</p>

ssociation of HLA class I and II alleles with generalized vitiligo in Chinese Hans in north China / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the association of HLA class I and II alleles with generalized vitiligo in ethnic Han Chinese in north China.</p><p><b>METHODS</b>By employing polymerase chain reaction sequence-specific primer (PCR-SSP) procedure 34 generalized vitiligo patients in north China were studied for HLA I and II alleles and were compared with 102 healthy controls.</p><p><b>RESULTS</b>The allelic frequencies of HLA-A*30, Cw*06, DRB1*07, and DQB1*0201 were increased significantly in generalized vitiligo and especially in the patients without family history compared with the controls.</p><p><b>CONCLUSION</b>These alleles positively associated with generalized vitiligo in Chinese Han patients in north China, might provide clues to reveal the susceptibility gene(s) of vitiligo in Chinese and as well as the immunnogenetic mechanisms of disease.</p>

Association between pemphigus vulgaris and human leukocyte antigen in Han nation of northeast China / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the relationship between pemphigus vulgaris (PV) and human leukocyte antigen (HLA) in Han nation of northeast China.</p><p><b>METHODS</b>Standard microcytotoxicity test and polymerase chain reaction-sequence specific primers method were used to detect the HLA class I antigens and HLA-DRB1 and DQB1 alleles in 27 patients with PV and results were compared with control group.</p><p><b>RESULTS</b>Gene and phenotype frequencies of HLA-A3, A26(10), B60(40), and B13 (27.99%, 48%; 16.11%, 30%; 23.02%, 41%; 16.11%, 30%, respectively) increased significantly in PV group compared with control (1.01%, 2%; 0.5%, 1%; 4.61%, 9%; 5.13%, 10%, respectively). After P value correction, the difference of A3, A26 (10), and B60 (40) between the two groups was still significant. The gene frequencies of HLA-DRB1*140x (1401, 1404, 1405, 1407, 1408), DRB1*120x, and DQB1*0503 alleles in PV group (42.26%, 25.46%, and 23.02%) were significantly higher than control group (5.09%, 7.74%, and 1.89%). After P value correction, the difference was still significant between the two groups.</p><p><b>CONCLUSION</b>PV significantly relates with HLA in PV patients of Han nation of northeast China.</p>