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At least 469 records · Page 26Linked to original sources
PubMed1999

Primary immune response in skin and skin-associated lymphoid tissue of interleukin-4 transgenic mice.

The interleukin-4 transgenic mice investigated here exhibit a ubiquitous expression of interleukin-4 in all organs, including the skin. In this study, the induction phase of oxazolone-induced local primary contact hypersensitivity and croton oil-induced irritant contact dermatitis in transgenic and wild-type mice was analysed. Compared to wild-type mice, the transgenic mice showed a decreased activation of the skin-draining lymph nodes but a strong hyperreactivity in the skin after topical sensitisation. In contrast to this, both the transgenic and the wild-type mice developed a strong and comparable inflammatory skin reaction after topical irritation. A striking increased expression level of tumour necrosis factor-alpha and macrophage inflammatory protein-2 genes were found in the skin of the transgenic mice during primary local contact hypersensitivity, while both the transgenic and the wild-type mice developed comparable expression levels of these cytokines during irritant contact dermatitis. Compared to wild-type mice, a strongly enhanced expression level of interleukin-6 transcripts derived from epidermal antigen presenting cells were detected in the skin of IL-4 transgenic mice, whereas in the skin-draining lymph nodes of transgenic mice significantly lower levels were detected. We conclude that the migration of epidermal antigen-presenting cells towards the skin-draining lymph nodes is reduced in transgenic mice, which could be due to the different cytokine balance in these mice strains. The atypical irritant-like reaction observed in transgenic mice after topical sensitisation is a phenomenon comparable to atopic diseases and therefore this transgenic strain might be a helpful model for investigating the immunopathophysiological features of these diseases.

Animals↗
PubMed2000

Survey of infectious skin diseases and skin infestations among primary school students of Taitung County, eastern Taiwan.

BACKGROUND: There are no complete records on the prevalence of childhood skin diseases in Taiwan. We conducted a survey of infectious skin diseases and skin infestations among primary school children in Taitung County, which is located in southeastern Taiwan. METHODS: From March 1998 through October 1998, a total of 3,029 students from four rural districts (Changbin, Yanping, Lanyu, and Dawu) and one urban area (Taitung City of Taitung County) were examined by dermatologists. Treatment and instructions for disease care were given immediately after the diagnosis of dermatoses, when appropriate. RESULTS: The most common infectious skin diseases and infestations were pediculosis capitis (12.9%), verruca vulgaris (5.1%), tinea versicolor (4.4%), tinea pedis (4.1%), verruca plantaris (1.8%), and scabies (1.4%). Most skin diseases, including pediculosis capitis, scabies, verruca vulgaris, verruca plantaris, folliculitis, pyoderma, tinea pedis, and tinea versicolor, were significantly more common in rural areas than in the urban area (p < 0.05 for all). Pediculosis capitis was more common among girls (p < 0.001), but tinea pedis and tinea versicolor were more common among boys (p < 0.05). CONCLUSIONS: The prevalence of most skin infections and infestations are much higher in rural Taitung County than in Taitung City. Prevention and treatment of these skin diseases should be reemphasized in the education of teachers, as well as students and their families. Adequate dermatologic training of nurses and physicians and the development of teleconsultation and teledermatology in rural areas might decrease the prevalence of these skin diseases in school children.

Child↗
PubMed2002

[Influence of the stratum corneum and dermis of the skin on the percutaneous absorption of fluorouracil delivered through skin patch].

OBJECTIVE: To investigate the respective influence of skin layers, specifically the stratum corneum (SC) and the viable layer, and isopropyl myristate (IPM), an absorption enhancer, on the permeability (K(p)) of drug. METHODS: Patches saturated with fluorouracil (5-FU), which was used as a test drug, were prepared. The Franz diffusion experiment via different rat skin layers was carried out, and high-performance liquid chromatography (HPLC) or gas chromatography (GC) was employed to determine the contents of 5-FU and IPM. K(p) of 5-FU in various conditions was calculated. RESULTS: The K(p) of 5-FU via SC -stripped skin was 2.3 times that via intact skin, and in the presence of IPM, K(p) was 1.8 times that via intact skin and 2.4 times that via SC-stripped skin. CONCLUSION: The permeability of 5-FU is enhanced after the SC is stripped, and IPM can overcome the barrier of SC in intact skin to facilitate 5-FU absorption, but can not enhance the K(p) of 5-FU via SC-stripped skin.

Administration, Cutaneous↗
PubMedDate not supplied

Activation of Akt and mTOR in CD34+/K15+ keratinocyte stem cells and skin tumors during multi-stage mouse skin carcinogenesis.

BACKGROUND: The goal of the present studies was to localize two proteins known to be involved in regulation of cell proliferation and survival in specific cell populations in normal SENCAR mouse skin and during multi-stage skin carcinogenesis. The proteins evaluated included activated Akt, as defined by phosphorylation of Akt at Serine-473 (pAkt) and mammalian target of rapamycin (pmTOR), defined by phosphorylation of mTOR at Serine-2448 (pmTOR). The cell populations examined included mouse keratinocyte stem cells (KSCs) within hair follicles and preneoplastic papilloma cells. MATERIALS AND METHODS: Immunochemical staining analysis as well as triple color immunofluorescence in combination with confocal microscopy were used to evaluate the presence of activated Akt and mammalian target of rapamycin (mTOR) in KSCs within the bulge niche of hair follicles, as identified by expression of the specific markers of mouse KSCs, CD34 and cytokeratin 15 (K15). Western blot analysis was used to examine CD34 and K15 protein levels in dorsal skin isolated from SENCAR mice during multi-stage skin carcinogenesis. RESULTS: CD34+/K15+ KSCs were located only in the outer root sheath (ORS) of a specific niche within hair follicles defined as "the bulge". The location of CD34+/K15+ KSCs remained restricted to the bulge region throughout the 22-week time-period examined during which pre-malignant papillomas developed and rapidly expanded. There was a significant decrease in K15 protein levels at 24 h and 15 weeks in dorsal skin treated with DMBA/TPA compared to CD34 protein levels. CD34+ cells within the numerous hair follicles in hyperplastic skin were found to undergo proliferation during the process of multi-stage skin carcinogenesis based on their staining with antibodies directed against proliferating cell nuclear antigen (PCNA). While pAkt was present within the bulge region of hair follicles, pmTOR was present in cells in the ORS of the bulge region as well as the upper infundibulum of hair follicles in dorsal skin treated with acetone. Within papillomas tissues isolated at 15 weeks following DMBA/TPA treatment, pAkt was localized to suprabasal cells with nominal staining of pAkt in the basal cell layer. There were fewer cells within the basal cell layer that contained pmTOR, in addition to the presence of pmTOR in suprabasal cells within papillomas. CONCLUSION: These results provide first time evidence for pAkt and pmTOR in CD34+/K15+ KSCs localized to the outer root sheath niche of the bulge region of mouse hair follicles. Taken together, the present observations suggest that pAkt and pmTOR may allow this cell population to evade terminal differentiation and to persist for long periods of time in their specific niche. Strategies that target pAkt and pmTOR may deplete both cells within the CD34+/K]5+ KSCs compartment, as well as impacting the survival of nonproliferating suprabasal cells within pre-malignant papillomas.

Animals↗
PubMed1986

A finite element model of skin deformation. I. Biomechanics of skin and soft tissue: a review.

Skin flap design has traditionally been based on geometric models which ignore the elastic properties of skin and its subcutaneous attachments. This study reviews the theoretical and experimental mechanics of skin and soft tissues (I) and proposes a mathematical model of skin deformation based on the finite element method (III). Finite element technique facilitates the modeling of complex structures by analyzing them as an aggregate of smaller elements. This paper gives the results of an animal model developed to study the deformation and mechanical properties of skin, including its viscoelastic properties (hysteresis, creep, and stress relaxation). A new skin extensometer, constructed with digital stepper motors and controlled with a microcomputer, is described to measure these properties for both skin and its subcutaneous attachments. Deformation grids quantitated from photographs with a digitalizing tablet are presented, and computer software is introduced to standardize and analyze them (II). The mathematical model is used to simulate wound closures such as the ellipse and rectangular advancement flap. In addition, a series of mathematical experiments performed to simulate deformation of a strip of skin are described; the relationships between the various elastic constants are investigated; and a comparison of these simulations with actual deformation is presented. Limitations of the model and areas for future investigation are discussed (III).

Animals↗
PubMed1986

A finite element model of skin deformation. II. An experimental model of skin deformation.

Skin flap design has traditionally been based on geometric models which ignore the elastic properties of skin and its subcutaneous attachments. This study reviews the theoretical and experimental mechanics of skin and soft tissues (I) and proposes a mathematical model of skin deformation based on the finite element method (III). Finite element technique facilitates the modeling of complex structures by analyzing them as an aggregate of smaller elements. This paper gives the results of an animal model developed to study the deformation and mechanical properties of skin, including its viscoelastic properties (hysteresis, creep, and stress relaxation). A new skin extensometer, constructed with digital stepper motors and controlled with a microcomputer, is described to measure these properties for both skin and its subcutaneous attachments. Deformation grids quantitated from photographs with a digitalizing tablet are presented, and computer software is introduced to standardize and analyze them (II). The mathematical model is used to simulate wound closures such as the ellipse and rectangular advancement flap. In addition, a series of mathematical experiments performed to simulate deformation of a strip of skin are described; the relationships between the various elastic constants are investigated; and a comparison of these simulations with actual deformation is presented. Limitations of the model and areas for future investigation are discussed (III).

Animals↗
PubMed1996

[Use of thermographic methods for estimation of skin prick test results. II. Evaluation of skin prick test results with histamine solutions of different concentration using liquid crystal mixtures].

The aim of the study was to evaluate the usefulness of liquid crystal thermography in interpretation of skin prick tests with selected allergens and different solutions of histamine. The study group consisted of 35 young adults with indications for skin prick tests, and in whom skin tests with different solutions of histamine were also carried out (10 mg of histamine per 1 ml diluted to a concentration of 1:1, 1:10, 1:100). The skin reaction was assessed visually after 15 minutes, measuring flare and wheal diameter and utilizing the liquid crystal thermographic method--assessing the diameter of each colour green, blue, violet. For statistical purposes the area was also calculated. A correlation of each area was performed with the wheal and flare diameter. The area of the skin reaction was largest for both methods using the undiluted solution of histamine, the smallest using the 1:100 dilution. The liquid crystal thermographic method showed larger areas of skin lesions than those using only the visual method by analyzing the size of the wheal and flare. Due to this fact skin tests should be carried out at lest 9 cm apart from each other. The largest correlation was found between diameter of the flare and area of blue colour of the liquid crystal thermographic method (registering the temperature of 34.3 degrees C-36.3 degrees C). Using the thermographic method a joint temperature analysis of the wheal and flare lesions are performed. The results of this study correspond with the earlier, preliminary studies showing the usefulness of the liquid crystal thermographic method in assessing skin reactions to different allergens and histamine solutions.

Adolescent↗
PubMed1996

Pixe analysis of pathological skin with special reference to psoriasis and atopic dry skin.

The nuclear microprobe is used for element analysis of human skin cross sections, providing new insight into the physiology of normal and pathological conditions. Special interest is focused on trace elements as they work as secondary messengers or regulatory substances. The distribution of ions in normal tissues serves as reference for pathological changes. Calcium (Ca2+) is assumed to take an important role in the differentiation process of the epidermis. This paper presents new data on elemental and trace elemental distributions in skin. Samples are prepared from skin biopsies obtained from patients with skin disorder and from individuals with no records of skin disorder serving as controls. Using the nuclear microprobe, both elemental maps and quantitative depth profiles are obtained. Previous findings of abnormal Fe distribution in psoriatic skin are confirmed, and new observations of altered Zn and Ca profiles in atopic skin are reported. The relation to possible physiological/biochemical mechanisms and apoptosis ("programmed cell death") is discussed. The study is a part in a larger survey aiming at an understanding of the formation of a mature stratum corneum with a functional barrier, and its changed properties in cases of skin disorder.

Apoptosis↗
PubMed1986

Carcinogen metabolism in human skin grafted onto athymic nude mice: a model system for the study of human skin carcinogenesis.

Human skin grafted onto athymic nude mice maintains its major histological features and may provide a useful system with which to assess the carcinogen interaction with human skin. Significant differences were observed in basal levels of cytochrome P-450 and cytochrome P-448-dependent monooxygenase activities between human grafted and nude mouse epidermis. Topical application of crude coal tar (CCT) to human skin transplanted onto nude mice resulted in 3.9 & 3.5; 3.2 & 2.9 and 1.1 & 1.2 fold increases in mouse and human epidermal aryl hydrocarbon hydroxylase (AHH), ethoxyresorufin deethylase (ERD) and ethoxycoumarin deethylase (ECD) activities, respectively. CCT applied topically to mouse skin resulted in 27.8 & 6.4; 12.8 & 3.3 and 1.7 & 2.6 fold increases in mouse and human epidermal AHH, ERD and ECD activities, respectively. Topical application of coal tar either onto human transplanted skin or to mouse skin also resulted in substantial induction of hepatic and pulmonary AHH and ERD activities. These studies indicate that human skin grafted onto nude mice preserves its metabolic capacity and offers a useful model system with which to assess the effects of polycyclic aromatic hydrocarbons and CCT on cutaneous xenobiotic metabolism in the human population.

7-Alkoxycoumarin O-Dealkylase↗
PubMed1996

Non-melanoma skin cancer and solar keratoses. I. Methods and descriptive results of the South Wales Skin Cancer Study.

This study aimed to describe the prevalence and incidence of solar keratoses and skin cancers and the natural history of solar keratoses in a random population sample. It was a cross-sectional study, with follow-up, conducted in South Wales, and involved 1034 subjects aged 60 years and over drawn from the Family Health Services Authority register. The main outcome measures were detection of the presence of solar keratoses and skin cancers on sun-exposed skin and photographic validation of solar keratoses and biopsy confirmation of cancers wherever possible. We found that solar keratosis prevalence was 23% (95% confidence interval 19.5-26.5) and that of skin cancer (all types) 2% (95% confidence interval 1.0-3.5). The incidence rate of solar keratoses was 149 lesions per 1000 person-years and of non-melanoma skin cancer 9 per 1000 person-years. In all 21% (95% CL 16-26) of solar keratoses regressed spontaneously during follow-up. None underwent malignant change. We believe that the failure of individuals to seek medical advice and the variable under-registration of non-melanoma skin cancer makes population-based study important. The high prevalence and incidence of malignant and pre-malignant skin lesions in this random sample raise major public health concerns. The high rate of spontaneous regression of solar keratoses and the low rate of malignant change challenges conventional views about the need for routine treatment of these lesions.

Adult↗
PubMed1991

Calcium deposition in the skin of a hemodialysis patient with widespread skin necrosis.

Rapidly progressive skin necrosis involving large areas of the skin associated with extensive vascular calcification was observed in a 39-year-old male patient on chronic hemodialysis. Histological examination of the periphery of a skin ulcer showed that subepidermal arterioles were occluded with fibrin deposits and that calcification was demonstrated in subcutaneous small arteries and arterioles. Electron microscopically, electron-dense materials, granular, crystal-like, vacuolar, or laminated, were found not only in arterial walls of the periphery of an ulcer but also, to a lesser extent, in those of normal-appearing skin. The skin necrosis gradually healed with antiseptic topical treatments and the injection of recombinant erythropoietin. The relationship between the vascular lesions in hemodialysis patients and progressive skin necrosis is not well known, although a combination of local and systemic factors may play an important role in the development of vascular calcification and skin necrosis in uremic and hemodialysis patients.

Adult↗
PubMedDate not supplied

Assessment with the dermal torque meter of skin pliability after treatment of burns with cultured skin substitutes.

The assessment of visco-elastic (V-E) properties in cutaneous scars is critical to reduction of impairment and restoration of function after grafting of excised burns. Cultured skin substitutes (CSS) that consist of autologous keratinocytes and fibroblasts attached to biopolymer substrates are alternatives for permanent closure of excised, full-thickness burns, but assessment of scarring has been subjective. V-E properties of CSS were measured with a Dia-Stron Dermal Torque Meter (DTM 310, Dia-Stron, Ltd, Broomall, Pa), which applies a constant torque (10 mNm) for a fixed interval (10 seconds) and measures rotational deformation and recovery. Parameters of skin deformation were measured in patients (n = 10) after grafting of CSS or meshed skin autograft. Native human skin (NHS) of healthy volunteers (n = 13) served as the control. Skin healed after treatment with CSS or autograft was evaluated for 1 year or longer after grafting. Elastic stretch (Ue), viscous stretch (Uv), total extensibility (Uf), elastic recovery (Ur), total recovery (Ua), and residual plasticity (R) were measured as degrees of rotation, were tested for significance (P < .05) by Student t test comparisons between treatment groups and controls, and were subjected to regression analysis. Assessment of burn scar with the Dermal Torque Meter detected time-dependent increases of all individual parameters of V-E properties for both CSS and autograft during the first year after grafting. At 1 year or later, no statistical differences were found between CSS and autograft for individual parameters, but Ue and Ur for autograft were significantly lower than for NHS. At 1 year or longer, autograft was significantly different from CSS or NHS, with a greater ratio of Uv to Ue, and both graft types had a lower ratio of Ur to Uf than NHS had. These results suggest that instrumental measurement of scar pliability may increase objectivity in assessment of patient recovery and establish an absolute scale for quantitative analysis of V-E properties in skin after grafting of conventional or alternative skin substitutes.

Biocompatible Materials↗
PubMed1993

A skin-stretching device for the harnessing of the viscoelastic properties of skin.

A skin-stretching device that is designed to harness the viscoelastic properties of the skin using incremental traction is presented as an addition to the surgeon's armamentarium. It has proved to be of value in helping to close problematic areas of skin shortage which would otherwise have required more complicated procedures for their solution. It is simple in application and can even be put to use at the bedside. It consists of two pins that are threaded through the dermis of the wound margins on either side of the defect and which are in turn engaged by the hooks of the stretching device. The stretching force on the skin margins is spread over a wide area, thus preventing damage to the skin itself that individual hooks applied to the skin might cause. The device is employed over a duration of 20 to 30 minutes to 1 to 3 days depending on the condition of the skin adjoining the defect. The device can be applied over three different periods of time: (1) preoperatively (presuturing), lasting 1 to 2 days, (2) intraoperatively, extending over a period of 20 to 30 minutes, and (3) postoperatively (or delayed), which takes place over a time span of hours to 1 to 3 days. Five illustrative cases are presented.

Adult↗
PubMed1990

The effects of an abrasive agent on normal skin and on photoaged skin in comparison with topical tretinoin.

Two studies were designed to assess the effect of abrasive preparations on the skin and to test the specificity of the effect of topical tretinoin in the management of chronic photodamage to the skin. In the first study two abrasive preparations (Brasivol fine and Brasivol medium) were compared with white soft paraffin and no treatment in eight volunteer subjects for their effects on the epidermis. The study was conducted over 3 days and measurements were taken of the effects on dansyl chloride-induced fluorescence to assess desquamation, epidermal thickness, and the tritiated thymidine autoradiographic labelling index. The abrasives were found to increase the desquamation rate significantly and to increase epidermal thickness and the epidermal labelling index compared to white soft paraffin and no treatment. In the second study the effect of one of the abrasive preparations (Brasivol medium) was compared with 0.05% tretinoin cream (Retin A) on the photodamaged skin of the dorsal aspects of the forearms of 12 subjects over an 8-week period. Cutaneous blood flow measured by the laser-Doppler flowmeter was found to be significantly increased in the abrasive-treated sites, but there was only a non-significant trend to increased blood flow in the tretinoin-treated sites. Measurements of skin thickness using pulsed A-scan ultrasound demonstrated that both treatments produced significant increases in thickness over the 8-week period but the increase was greater for the abrasive treated site. Measurements of the skin extensibility at the treated sites were made using a uniaxial extensometer. Forces needed for 30% skin extension were increased in the abrasive-treated sites only. Measurements of epidermal thickness and of [3H]-thymidine autoradiographic labelling indices showed greater increases in the abrasive-treated sites than in tretinoin-treated sites compared to untreated sites, but these increases were not statistically significant. No significant inflammation and no changes in the degree of elastosis or the presence of a 'repair zone' were found in any of the post-treatment biopsies. The results indicate that some of the changes produced in the skin by topical tretinoin that are taken to indicate a specific antiphotoageing effect may not in fact be specific and can be achieved by an abrasive preparation.

Adult↗
PubMed1999

A role for T helper 2 cells in mediating skin fibrosis in tight-skin mice.

Mice heterozygous for the tight-skin (Tsk) mutation develop skin fibrosis. Previous studies have implicated a role for the immune system and, specifically, CD4(+) T cells, in the etiology of skin fibrosis in Tsk/+ mice. We have recently shown that the administration of neutralizing anti-IL-4 antibodies to Tsk/+ mice prevented the development of skin fibrosis in these mice. Since IL-4 is a major cytokine produced by T helper 2 (Th2) cells, we investigated the role of Th2 cells in mediating skin fibrosis in Tsk/+ mice. Previous studies have shown that the development of Th2 cells in non-Tsk mice is abrogated in mice with null mutation for either the IL-4 or the Stat6 gene. In this study we showed that the polarization of CD4(+) T cells from Tsk/+ mice toward the Th2 lineage is also dependent on a functioning IL-4 or Stat6 gene. More importantly, the development of skin fibrosis in Tsk/+ mice was abrogated by the IL4(-/-) or the Stat6(-/-) mutation. We also determined whether alteration of the TCR repertoire in Tsk/+ mice, achieved by the introduction of TCR transgenes, was able to prevent the development of skin fibrosis in Tsk/+ mice. We found that the exclusive usage of the Vbeta8.2 gene segment by T cells was sufficient to prevent skin fibrosis in Tsk/+ mice. This result suggests that the exclusive use of this Vbeta gene segment by T cells may have prevented the development of fibrosis-causing Th2 cells.

Animals↗
PubMed2003

[Reconstruction of the urethral plate or ventral penile skin with foreskin or penile skin island flaps].

PURPOSE: Reconstruction of urethral plate with hairless skin. Reconstruction of ventral penile skin in patients with hypospadia. MATERIAL AND METHODS: Utilization of foreskin or a circular penile island flap to form the urethral plate. Second stage urethral reconstruction with buccal mucosa. Resurfacing of the ventral surface of the penis with a foreskin island flap using the buttonhole technique. An innovation in contrast to previously described procedures is the resection of a transversal strip of dorsal penile skin to avoid bulky wedges of skin on the sides of the penis. MATERIAL AND RESULTS: The urethral plate was reconstructed in 2 hypospadia-scripples and in one patient with penoscrotal hypospadia. Urethra reconstruction with buccal mucosa was accomplished without complications in 2 patients in a second stage. Partial necrosis of the most distal port of penile skin was observed as a complication after the first operation in one patient. Functional and cosmetic results were good after treatment with split skin thickness grafts. The penis was straightened in 2 patients with hypospadis sine hypospadis and the urethra reconstructed according to Mathieu in 3 patients with distal urethral defects. The ventral skin defect was covered with an outer leaflet of foreskin island flap using the buttonhole technique. Complications were not observed postoperatively or in later follow-ups. Functional and cosmetic results were good in all patients. CONCLUSION: The foreskin island flap is excellent for reconstruction of missing skin on the ventral shaft of the penis.

Adolescent↗
PubMed1998

Eccentric skin resection and purse-string closure for skin reduction with mastectomy for gynecomastia.

Skin redundancy following mastectomy for gynecomastia does not shrink and resolve in a predictable manner. Excess skin can be addressed best with resection at the time of the original operation if the scar can be minimized. Previously described techniques for resection of skin have shortcomings that include unacceptable scars, poor nipple positioning, and bulkiness of redundant, folded dermal tissue. The current technique for grade 2 and some grade 3 gynecomastias is performed with the creation of a 20-mm-diameter nipple-areolar complex based as a cephalad flap and designed eccentrically around the existing nipple. Eccentric skin resection in the vertical and horizontal planes is performed below the areolar flap. Wide access for completion of mastectomy is gained. The wound is then closed with a subcutaneous purse-string suture and inset of the areolar flap so that the scars are confined to the circumareolar area. This allows immediate skin recontouring with minimal skin scar. The patient does not have to endure prolonged anxiety while awaiting skin contracture, and this procedure eliminates the possible need for secondary surgery to resect redundant skin.

Anesthesia, Local↗
PubMed1993

C3d,g deposits in inflammatory skin diseases: use of psoriatic skin as a model of cutaneous inflammation.

Recent studies in our laboratories have shown that human keratinocytes synthesize and secrete complement components including C3. Moreover, human keratinocyte-derived C3 is regarded as a potential source of C3d,g, a recently described constituent of the sublamina densa region of normal epidermal basement membrane. Additionally, human keratinocyte-derived C3 may also contribute to epidermal basement membrane deposits of C3 in autoimmune or inflammatory skin disorders. To further our understanding of the specificity and origin of epidermal basement membrane C3 deposits in normal and diseased skin, we have characterized in situ deposits of C3 and C3 cleavage fragments in various inflammatory skin diseases and utilized a skin equivalent model to assess the deposition of C3 cleavage fragments in neo-basement membrane of epidermal outgrowths from normal or diseased human skin. C3d,g reactivity was found to be greater in all samples of inflamed skin, and typically associated with C3c reactivity at these sites. No immunoglobulins or other complement components were detected. When lesional psoriatic skin rich in epidermal basement membrane C3c was used in our organ culture system, C3 incorporation within neo-basement membrane was observed. These results show that human keratinocyte-derived C3 may contribute to inflammatory reactions in skin as well as account for deposits of C3d,g in normal epidermal basement membrane.

Basement Membrane↗