Sex,constancy, and skin bacteria

Summary Quantitative studies of the aerobic flora of seven skin sites in 16 volunteers were repeated after 3 months. The total aerobic densities of the sites differed, male carried more organisms than females and also more biotypes. Qualitative differences in the flora could be detected.     

Immunohistochemical localization of type V collagen in normal human skin

Summary Tissue distribution of type V collagen in normal human skin was studied using an indirect immunofluorescent technique to determine whether type V collagen is present in the interstitium or in the basement membrane. Type V collagen was isolated from the human placenta by pepsin digestion and was purified with fractioning salt precipitations. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that type V collagen contained 1(V) and 2(V) chains, but not the 3(V) chain. Specificity of the rabbit antibodies to type V collagen was assessed using enzyme-linked immunosorbent assay (ELISA) and an immunoblotting method. Antibodies showed no cross-reactivity to other collagens, laminin, and fibronectin. With an indirect immunofluorescent technique, type V collagen was found to be widely distributed throughout the dermis. Intense fluorescent staining was noted in the papillary dermis and adnexal dermis surrounding hair follicles and eccrine glands. The basement membrane of the dermoepidermal junction, skin appendages, and capillaries was not stained. By indirect immunoperoxidase double staining, type V collagen was not found to be deposited on type IV collagen present in the basement membrane. Immunoelectron microscopic studies showed that type V collagen was not located in the basal lamina. These results suggest that type V collagen is distributed in the interstitium, but not in the basement membrane of normal human skin.     

Heat-separation of normal human skin for epidermal and dermal prostaglandin analysis

Summary Heat-separation was introduced as a simple, reliable method of obtaining pure epidermis and dermis for prostaglandin (PG) analysis. Heating of normal human skin at 60°C for 1 min resulted in a distinct separation of the epidermis from the dermis. After heat-separation the mean concentration ±SEM of PGE₁ activity in normal epidermal tissue was 2906±281 pg/mg dry weight. The PGE₁ level in the corresponding dermal samples was 30±4 pg/mg dry weight and the mean leakage of PGE₁ from the tissue into the buffer used during heating was 426±54 pg/ml.This work was supported by grant 512-8125 from the Danish State Research Foundation     

Distribution of carbohydrate residues in normal skin

Summary Sections of biopsies of normal skin obtained from 11 individuals were incubated with 8 lectins using an avidin-biotin complex (ABC). All sections when incubated with the appropriate lectin showed the presence of the following carbohydrate residues: l-fucose, -(1–4)-d-GlcNAc)₂ (N-acetylglucosamine), acetylneuraminic acid, Gal--(1–3)-GalNAc (N-acetyl-galactosamine), -d-galactose, -d-glucose, and -d-mannose. In addition, sections of individuals with blood group A showed -d-GalNAc and sections of individuals with blood group B showed -d-galactose. In the stratum (str.) basale, carbohydrates were present in small quantities, but as the cells matured and moved upward, the incorporation of carbohydrates into the cell membranes increased considerably. In the str. granulosum, lectin reactivity was absent in many sections, probably due to masking by phospholipids. The dark cells in the eccrine glands showed reactivity with all lectins except in the one nonsecretor with blood group A₁, whose dark cells showed no l-fucose and -d-GalNAc. The endothelial cells of the blood vessels showed lectin reactivity except when incubated with concanavalin A. The sebaceous glands showed both cytoplasmic and membrane staining when incubated with various lectins.     

Prostaglandin E1 in normal human skin: Methodological evaluation,topographical distribution and data related to sex and age

Summary A methodological evaluation of a radioimmunoassay technique for PGE₁ measurement was applied to normal human skin. The detection limit of the assay was 15 pg and recovery (mean±SD) was 90±6%. The mean value of PGE₁ (±SEM) in nine punch biopsy specimens (4 mm in diameter) from a piece of skin surgically removed from one person was 117±14 pg/mg dry weight. The individual variation of PGE₁ activity in biopsy specimens from the same topographical area in ten persons belonging to the same sex and age group was 33±4 pg/mg dry weight. The influence has been elucidated of temperature and tissue processing, local anaesthesia, sex, age and topographical distribution on endogenous PGE₁ activity.Supported by grant 512–8125, 512–15539 and 12–1690 from the Danish Medical Research Council     

非特应性的湿疹皮炎患者皮肤菌群的测定与分析

目的：探讨非特应性的湿疹皮炎患者携带细菌尤其是金黄色葡萄球菌（金葡菌）的携带情况。方法：选取正常人30名及门诊非特应性的湿疹皮炎患者186例，以棉签法分别在正常人及皮损部位反复擦拭后进行细菌培养及鉴定。结果：正常人未检出金葡菌；湿疹继发感染患者皮损金葡菌及细菌总检出率均为92.9%；非特应性的湿疹皮炎患者金葡菌检出率和细菌总检出率分别为30.1%和67.7%；临床无感染的湿疹皮炎患者金葡菌检出率和细菌总检出率分别为25.0%和65.7%，后两者金葡菌及细菌总检出率均显著低于湿疹继发感染患者，而金葡菌检出率显著高于正常人。结论：金葡菌与一部分非特应性的湿疹皮炎可能有一定的关系。     

Xenobiotic metabolizing enzymes in human skin and SkinEthic reconstructed human skin models

Skin metabolism is becoming a major consideration in the development of new cosmetic ingredients, skin being the first organ exposed to them. In order to replace limited samples of Excised human skin (EHS), in vitro engineered human skins have been developed. 3D models are daily used to develop and evaluate new cosmetic ingredients and have to be characterized and compared with EHS in terms of metabolic capabilities. This work presents the determination of apparent catalytic parameters (apparent Vmax, Km and the ratio Vmax/Km) in 3D models compared with EHS for cytochrome P450 dependent monooxygenase isoforms involved in drug metabolism, esterases, alcohol dehydrogenases, aldehyde dehydrogenases, peroxidases, glutathione S‐transferases, N‐acetyl transferases, uridinyl diphosphate glucuronyl transferases and sulfotransferases. Results show that all these enzymes involved in the metabolism of xenobiotics are expressed and functional in the EHS and 3D models. Also, the Vmax/Km ratios (estimating the intrinsic metabolic clearances) show that the metabolic abilities are the most often comparable between the skin models and EHS. These results indicate that the 3D models can substitute themselves for EHS to select cosmetic ingredients on the basis of their metabolism, efficacy or/and safety.     

Effect of UVB 311 nm irradiation on normal human skin

Ultraviolet radiation B (UVB) on the skin induces erythema, inflammation and modifications of the immune system. These changes have been reported after excessive short-term or long-term exposure to broad spectrum UVB. In this study, we examined the effects of local repetitive UVB irradiation of 311 nm wavelength on the skin of seven young volunteers. Skin biopsies were taken before and after UVB irradiation, and we immunohistochemically analyzed the expression of CD1a and HLA-DR antigens of Langerhans cells (LC), the possible infiltration of dermis/epidermis by CD11b macrophages, the modifications or the induction of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) involved in the binding of leukocytes to the endothelial surface and the development of perivascular infiltrates of LFA-1⁺ mononuclear cells. We also determined the expression of substance P receptors (SPR) using biotinylated substance P (SPB). Exposure of UVB 311 nm induced a drastic reduction of CD1a⁺ cells and a moderate increase of HLA-DR⁺ dendritic cells in the epidermis without infiltration by CD11b macrophages. An increase of the binding of SPB to upper layer epidermal cells was noted in five of seven biopsies. In the dermis, vessel-associated ICAM-1 expression increased and an induction of E-selectin occurred on nearly 20 to 40% of endothelial cells, but VCAM-1 expression remained undetectable. The percentage of LFA-1⁺ cells did not change significantly after irradiation. These observations may be compatible with a selective role of UVB 311 nm on the skin immune response.     

Intra- and inter-individual variations in cornified envelope peptide composition in normal and psoriatic skin

Summary Cornified envelopes from the stratum corneum of healthy volunteers and from the involved and uninvolved skin of psoriatic patients were electrophoretically purified, and their peptide composition analysed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE) after cyanogen bromide cleavage. The resulting envelope peptide patterns (EPPs) were compared. In normal subjects, mainly quantitative minor differences in the EPPs were observed between different individuals. In the same individual, palms and soles could be distinguished from other body sites by their EPPs. The palm and sole samples presented identical patterns which were different from the patterns found with samples from other body sites. In psoriatic patients, EPPs of uninvolved skin resembled closely those of healthy epidermis, but showed striking differences from those of lesional skin. The EPPs of psoriatic lesional skin showed a characteristic accumulation of small peptides with molecular weights of 3–11 kDa. The EPP of lesional skin returned to normal during PUVA therapy, indicating that the changes in the biochemical composition of the cornified envelope are correlated with the clinical status of the disease.     

The subbasement membrane distribution of type IV collagen in normal human skin

Samples of normal human skin were obtained from 48 sites in 26 subjects ranging in age from 2 to 85 years. The samples were examined by indirect immunofluorescence and immunoelectron microscopy using anti-human type IV collagen antibodies produced by immunizing rabbits with type IV collagen extracted from human placenta. Fluorescence was observed as granular or fine fibrous patterns, not only in the basement membrane at the dermo-epidermal junction, around the vessels, and the accessory organs of the skin, but also in the dermal regions in the vicinity of the basement membranes. This suggests the presence of type IV collagen in the dermis deep to the basement membrane. Ultrastructurally, the extrabasal lamina distribution of type IV collagen was noted as a partial distribution around the fibroblasts that existed close to the basal lamina. These findings are considered to be important in examining the function of this collagen in the dermis and the dynamics and metabolism of the basement membrane under normal and abnormal conditions.     

Increased risk of skin cancer associated with the presence of epidermodysplasia verruciformis human papillomavirus types in normal skin

BACKGROUND: Human papillomaviruses (HPVs) are found in normal skin and in benign and malignant skin conditions. Epidermodysplasia verruciformis (EV) HPV types are those most plausibly linked to the development of squamous cell carcinomas of the skin. OBJECTIVES: To assess the risk of nonmelanoma skin cancer (NMSC) associated with the presence of EV HPV in normal skin in immunocompetent (IC) individuals and renal transplant recipients (RTRs). METHODS: Using a degenerate and nested polymerase chain reaction technique, HPV DNA was sought in 124 normal skin samples from sun-exposed and nonsun-exposed sites, from 39 IC individuals and 38 RTRs, both with and without NMSC. Data were analysed using the Mantel-Haenszel test and by logistic regression analysis. RESULTS: HPV DNA was detected in 58/67 (87%) and 20/57 (35%) samples from renal transplant and IC patients, respectively. There was no difference in either the prevalence or spectrum of HPV types found in sun-exposed and nonsun-exposed normal skin. However, there was significant association between NMSC and the presence of EV HPV DNA. Multivariate analysis provided an odds ratio of 6.41 (95% confidence interval 1.79-22.9) for the association of EV HPV DNA in normal skin (irrespective of site) and NMSC status, even after stratifying for patient group and adjusting for the clustering effect of multiple sampling. Conversely, there was no association between skin cancer status and the presence of cutaneous or mucosal HPV types in either sun-exposed or nonsun-exposed skin. CONCLUSIONS: HPV DNA is widespread in normal adult skin, particularly in transplant patients. In our study, the presence of EV but not cutaneous HPV DNA in normal skin was significantly associated with NMSC status and may prove to be of predictive value for skin cancer risk. These data provide reason to focus on EV HPV types as causal agents in skin cancer.     

Expression of transferrin receptor in normal human skin, psoriatic skin and various skin tumors

The distribution of transferrin receptor in normal human skin and its expression in psoriatic skin and various skin tumors have been investigated. Immuno-peroxidase staining was performed on biopsy specimens using monoclonal OKT 9 antibody, which reacts with transferrin receptor. Normal human skin showed positive staining with OKT 9 in eccrine glands and outer root sheaths of the hair. Sebaceous glands were also strongly positive. The basal layer stained very weakly. Psoriatic skin expressed OKT 9 strongly in the epidermis, especially in the area of the rete ridge. In squamous cell carcinoma, Bowen's disease, and malignant melanoma, a widespread and strong labelling reaction was found. Basal cell epithelioma and genital Paget's disease were partially and moderately positive in their staining pattern. No such positive staining pattern could be found in either nevus cell nevi or seborrhoic keratosis. These findings indicate that, in normal skin, transferrin receptor exists in eccrine glands, sebaceous glands, and outer root sheaths of the hair in greater amounts. High amounts of expression of this receptor in psoriatic epidermis and malignant tumors suggests that immunohistochemical demonstration of transferrin receptor parallels the proliferating activity of the tissue or tumor of the skin and may provide an useful aid for detecting such conditions.     

Distribution density of intraepidermal nerve fibers in normal human skin

A total of 74 specimens was obtained from the normal human skin of patients from 3 to 90 years old. The specimens were roughly classified into 5 groups: 15 for the face group from the face; 15 for the abdomen group from the abdomen; 13 for the back group from the back; 14 for the arm group from the upper arm and forearm; and 17 for the leg group from the thigh and lower leg. They were all fixed in 4% paraformaldehyde and 14% saturated picric acid. Cryostat sections were examined by the immunoperoxidase method and indirect immunofluorescence (IF). Primary antibodies against neurofilament, neuron-specific enolase, protein gene product 9.5 (PGP 9.5) and S-100 protein were used. The most effective method was found to be the combination of IF with PGP 9.5; it visualized the intraepidermal nerve fibers easily and clearly. Of the 74 specimens, 32 (43%) had intraepidermal PGP 9.5-immunoreactive (or nerve) fibers (IPIF), and 42 (57%) did not have any. With reference to the different skin locations, the maximal rate of specimens having IPIF was 57% in the arm group, and the minimum was 23% in the back group. IPIF positive specimens had approximate surface lengths of 6 mm, in which the existence number of the IPIF was 1 to 75. Their distribution density per 1000 epidermal basal cells was highest at 9.63 in the arm group and lowest at 2.89 in the back group. Their thickness was 2.94 +/- 0.83 microns with no significant differences among the five groups. We concluded that intraepidermal nerve fibers may not be distributed evenly in the hairy portions of normal human skin, but they may be present focally. Physiologically, two-point discrimination of itch may be explained by the distribution mode of intraepidermal nerve fibers.     

Reproducible pattern of microRNA in normal human skin

Please cite this paper as: Reproducible pattern of microRNA in normal human skin. Experimental Dermatology 2010; 19 : e201–e205. Abstract: MicroRNAs (miRNAs) regulate cell growth, differentiation and apoptosis via specific targeting of messenger RNA (mRNA). Aberrant mRNA expression contributes to pathological processes such as carcinogenesis. To take advantage of miRNA profiling in skin disease it is essential to investigate miRNA expression pattern in normal human skin. Here we investigated miRNA expression profiles from skin biopsies of 8 healthy volunteers taken from sun protected and mildly photo damaged skin using the modified protocol for miRNA extraction. We were able to show a constant pattern of miRNA expression between different individuals. We did not find any significant differences in miRNA expression between sun protected and mildly photodamaged skin. These results may be valuable for future design of studies on miRNA expression in skin disease.     

Remittance spectroscopy mapping of human skin in vivo

Remittance spectroscopy of human skin may be influenced by probe application pressure and body site.

Methods:

We investigated remittance spectroscopy qualities of human skin in vivo in different areas: a) forearm, b) frontal, c) back, d) back of the hand, e) palms and f) cheek. Twenty volunteers of skin type 2–3 free of inflammatory skin diseases, were enrolled into the study. Spectroscopy readings were performed with a fiber optic spectrometer (Ocean Optics, USA). The readings were taken with standardized force (0 and 100 pont) by applying the probe vertically to the skin surface. The remittance in relation to wavelength was registered. White light with wavelengths from 420 to 750 nm were used. Individual remittance values and their standard deviations were obtained from 20 readings each.

Results/Conclusions:

Spectroscopic patterns of skin are influenced by external force and regional factors. Standardization remains critical for the use of this approach in bioengineering of skin.     

Immunolocalization of aquaporin-5 in normal human skin and hypohidrotic skin diseases

Aquaporin (AQP)‐5 has been shown to be expressed in the secretory parts of mouse, rat and horse sweat glands. However, the precise localization of AQP‐5 in normal and diseased human skin has not been fully determined. The aim of the present study was to further clarify the immunolocalization of AQP‐5 in normal human skin and hypohidrotic skin diseases. Normal human scalp skin and biopsies from skin affected by hypohidrotic diseases were analyzed for AQP‐5 and/or dermcidin expression by immunohistochemistry, immunofluorescence and/or immunoelectronmicroscopy. AQP‐5 was expressed on the apical and basolateral plasma membranes of the clear cells in eccrine sweat coils, but not in ductal components or apocrine glands. Numbers of AQP‐5‐positive coils in the secretory part of eccrine sweat glands were decreased in Sjögren’s syndrome, but not in skin affected by idiopathic segmental anhidrosis or idiopathic pure sudomotor failure. AQP‐5 was mostly localized to the plasma membranes of clear cells in the secretory coils of eccrine sweat glands, suggesting that it plays a role in producing the primary sweat fluid.     

Effect of betamethasone valerate on the normal human facial skin flora

Eighteen volunteers were randomly divided into two groups and allocated either an active corticosteroid preparation (Betamethasone valerate) or the basal formulation only (placebo). The cream was applied to the face twice daily for one month. The treated area was sampled by the scrub-wash method immediately before treatment began and after 2 and 4 weeks, and microorganisms were enumerated and identified. Application of either cream produced a very slight increase (less than or equal to 0.5 log cycle) in the skin flora during the first 2 weeks of treatment. There were no significant differences in the changes occurring between volunteers treated with placebo and those on the steroid formulation. The results are discussed in relation to theories of pathogenesis of perioral dermatitis and steroid acne.     

Comparative biochemistry of human skin: glycosaminoglycans from different body sites in normal subjects and in patients with localized scleroderma

OBJECTIVES: The aim of this investigation is to compare the relative proportions of disaccharides of chondroitinase-digestible glycosaminoglycans (GAGs) among the different body sites in control human skin and in the skin lesions of patients with localized scleroderma. METHODS: The disaccharide relative proportions were determined using high-performance liquid chromatography (HPLC). RESULTS: DeltaDi-4S, the main disaccharide unit of dermatan sulphate (DS), was the major skin GAG disaccharide (approximately 70% of the total) in control skin among all different body sites studied here. In scleroderma there was an increase in the relative proportion of both deltaDi-HA, the main disaccharide unit of hyaluronic acid (HA), and deltaDi-diS(B) (alpha-deltaUA(2SO4)-1-->3-GalNAc(4SO4)), derived from DS, and a decrease in deltaDi-4S, as compared with the uninvolved skin or the site-matched control skin. CONCLUSION: DS is the major GAG species in normal skin from different body sites. In addition, our results suggest a decrease and also a structural change in DS and an increase in the proportion of HA in scleroderma skin.