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Percy Lehmann

Publications and source records attributed to Percy Lehmann.

16 recordsLinked to original sources
PubMed2006

Accumulation of apoptotic cells in the epidermis of patients with cutaneous lupus erythematosus after ultraviolet irradiation.

OBJECTIVE: To examine whether apoptosis contributes to the pathogenesis of skin lesions in patients with cutaneous lupus erythematosus (CLE) after ultraviolet (UV) irradiation. METHODS: In situ nick translation and TUNEL were performed to detect apoptosis in 85 skin biopsy specimens from patients with various subtypes of CLE. Specimens from normal healthy donors and patients with polymorphous light eruption were used as controls. In addition to assessment of primary lesions, provocative phototesting was carried out to investigate events occurring secondary to UV irradiation during a very early stage of lesion formation. RESULTS: A significant increase in apoptotic nuclei was found in the upper epidermal layer of primary and UV light-induced skin lesions of CLE patients compared with controls. In tissue sections obtained from control subjects at 24 hours after a single exposure to UV light, a slight increase in the count of epidermal apoptotic nuclei was present as compared with skin tissue from CLE patients obtained under the same conditions before lesion formation. In sections obtained from controls at 72 hours after irradiation, a significant decrease in the apoptotic nuclei count was observed, consistent with a proper clearance of apoptotic cells in the period between 24 and 72 hours after irradiation. In striking contrast, the number of apoptotic nuclei increased significantly within this period in tissue sections from patients with CLE. CONCLUSION: These data support the hypothesis that apoptotic cells accumulate in the skin of patients with CLE after UV irradiation, as a result of impaired or delayed clearance. The nonengulfed cells may undergo secondary necrosis and release proinflammatory compounds and potential autoantigens, which may contribute to the inflammatory micromilieu that leads to formation of skin lesions in this disease.

Adult↗
PubMed2005

Evaluation of phototoxic and photoallergic potentials of 13 compounds by different in vitro and in vivo methods.

Phototoxic side effects of pharmaceutical and cosmetic products are of increasing concern for patients, dermatologists and the chemical industry. Moreover, the need of new chemicals and drugs puts pressure on pre-clinical test methods for side effects, especially interactive adverse-effects with UV-light. So, the predictive potential of different established test methods, which are used regularly in our departments in order to detect the phototoxic potential of chemicals, were analyzed. Namely the fibroblast 3T3 test, the photo hen's egg test, a guinea pig test for measuring acute photoreactions, and a modified Local Lymph Node Assay, the Integrated Model for the Differentiation of Skin Reactions. Various agents with different photoreactive potential were tested: quinolones like Bay y 3118, ciprofloxacin, enoxacin, lomefloxacin, moxifloxacin, ofloxacin, sparfloxacin, as well as promethazine, chlorpromazine, 8-methoxypsoralen and olaquindox serving as control. Special emphasis was taken to evaluate the capability of the employed test procedures to predict phototoxic side effects in patients. Following our results, both in vitro assays were useful tools to detect photoirritancy while the photoallergic potentials of tested compounds were exclusively detected by an in vivo assay. As long as no in vitro model for photoallergy is available, the UV-IMDS should be considered to evaluate photoallergic properties of a supposed photoreactive agent.

Animals↗
PubMed2005

Ultraviolet radiation-induced injury, chemokines, and leukocyte recruitment: An amplification cycle triggering cutaneous lupus erythematosus.

OBJECTIVE: To investigate the activation and recruitment pathways of relevant leukocyte subsets during the initiation and amplification of cutaneous lupus erythematosus (LE). METHODS: Quantitative real-time polymerase chain reaction was used to perform a comprehensive analysis of all known chemokines and their receptors in cutaneous LE lesions, and the cellular origin of these chemokines and receptors was determined using immunohistochemistry. Furthermore, cytokine- and ultraviolet (UV) light-mediated activation pathways of relevant chemokines were investigated in vitro and in vivo. RESULTS: In the present study, we identified the CXCR3 ligands CXCL9 (interferon-gamma [IFNgamma]-induced monokine), CXCL10 (IFNgamma-inducible protein 10), and CXCL11 (IFN-inducible T cell alpha chemoattractant) as being the most abundantly expressed chemokine family members in cutaneous LE. Expression of these ligands corresponded with the presence of a marked inflammatory infiltrate consisting of mainly CXCR3-expressing cells, including skin-homing lymphocytes and blood dendritic cell antigen 2-positive plasmacytoid dendritic cells (PDCs). Within cutaneous LE lesions, PDCs accumulated within the dermis and were activated to produce type I IFN, as detected by the expression of the IFNalpha-inducible genes IRF7 and MxA. IFNalpha, in turn, was a potent and rapid inducer of CXCR3 ligands in cellular constituents of the skin. Furthermore, we demonstrated that the inflammatory CXCR3 ligands cooperate with the homeostatic chemokine CXCL12 (stromal cell-derived factor 1) during the recruitment of pathogenically relevant leukocyte subsets. Moreover, we showed that UVB irradiation induces the release of CCL27 (cutaneous T cell-attracting chemokine) from epidermal compartments into dermal compartments and up-regulates the expression of a distinct set of chemokines in keratinocytes. CONCLUSION: Taken together, our data suggest an amplification cycle in which UV light-induced injury induces apoptosis, necrosis, and chemokine production. These mechanisms, in turn, mediate the recruitment and activation of autoimmune T cells and IFNalpha-producing PDCs, which subsequently release more effector cytokines, thus amplifying chemokine production and leukocyte recruitment, finally leading to the development of a cutaneous LE phenotype.

Cells, Cultured↗
PubMed2004

[Actinic prurigo].

Explore the source record for details and available documents.

Dermatologic Agents↗
PubMed2004

Phototoxicity of exogenous protoporphyrin IX and delta-aminolevulinic acid in the photo hen's egg test.

BACKGROUND: Oxygen, appropriate light sources, and special photosensitizers are necessary to induce photochemical damage in tumor cells via photodynamic therapy (PDT) delta-aminolevulinic acid (ALA) is increasingly used in PDT, because topical or systemic administration of ALA induces accumulation of endogenous porphyrins preferentially in neoplastic tissues. Subsequent radiation with light of approximately 630 nm leads to selective damage of tumor cells. PDT should optimally leave peritumoral tissues unaffected, but only few data are reported on the effects and the time course of ALA-induced porphyrins in tumor-free tissues. METHODS: Therefore, we studied the phototoxic effects of protoporphyrin IX (PP) and ALA-induced porphyrins in a recently established phototoxic model based on tumor-free tissue, the photo hen's egg test (PHET). RESULTS: Employing this test procedure, PP provoked strong phototoxic reactions when irradiated with Ultraviolet A immediately and up to 30 h after substance application. In contrast, ALA induced a significant phototoxic effect only if irradiated 24 h after application. CONCLUSION: Thus, we observed a delayed phototoxic effect of ALA in tumor-free tissue of the yolk sac (YS) blood vessel system. This delayed phototoxic response 24 h after ALA application is probably caused by endogenously synthesized porphyrins. In contrast, epithelial tumors show a maximum porphyrin accumulation 4-8 h after ALA application whereas in healthy human skin porphyrin synthesis is less intensive but prolonged with maximum levels 24-48 h after ALA application. Thus, ALA induced virtually the same delayed phototoxic effect in the tumor-free YS blood vessel tissue as in healthy human skin. These results show that the PHET is a useful model for the predictive preclinical risk assessment of exogenous or endogenous photosensitizers.

Aminolevulinic Acid↗
PubMed2004

[Pemphigoid gestationis--first sign of metastatic choriocarcinoma].

A 29-year-old woman developed pruritic urticarial plaques and vesicles 3 months after delivery of a healthy daughter. Two months later pemphigoid gestationis (PG) was diagnosed based on histopathological and immunopathological findings. At the same time elevated serum levels for beta-HCG and a large mass in the liver were noted. A liver biopsy confirmed the diagnosis of metastatic choriocarcinoma, which was responsible for the PG metastasis. Upon initiation of chemotherapy, complete healing of the PG was observed within 4 weeks and autoantibodies to BP180NC16A could no longer be identified. In parallel, both a decrease of beta-HCG levels and tumor size was observed.

Adult↗
PubMed2003

Histopathologic findings in lupus erythematosus tumidus: review of 80 patients.

BACKGROUND: In a recent study, we demonstrated that lupus erythematosus (LE) tumidus (LET) is a distinct subset of cutaneous LE (CLE), which is clinically characterized by erythematous, urticaria-like, nonscarring plaques in sun-exposed areas. OBJECTIVE: Our purpose was to analyze skin biopsy specimens from 80 patients with this disease and to determine whether it could be differentiated from other variants of CLE on histopathologic grounds. METHODS: Skin biopsy specimens from 53 primary and 38 UVA- and/or UVB-induced lesions of 80 patients with LET were examined and compared with skin biopsy specimens from patients with discoid LE (DLE) and subacute CLE (SCLE). RESULTS: Specimens from LET lesions showed a characteristic and diagnostic pattern of perivascular and periadnexal cellular infiltrates in the papillary and reticular dermis composed almost entirely of lymphocytes. In some cases, few scattered neutrophils were present. Furthermore, interstitial mucin deposition was observed in all specimens, as confirmed by colloidal iron staining. In contrast to discoid LE and subacute CLE lesions, epidermal atrophy or alteration at the dermoepidermal junction was not detected. CONCLUSION: Skin lesions of patients with LET present with specific histopathologic features, and the differences compared with subacute CLE and discoid LE further support the concept to consider LET as a separate entity of CLE.

Dermis↗
PubMed2003

Three-dimensional localization of sentinel lymph nodes using combined emission and transmission SPECT data.

PURPOSE: With conventional planar imaging, preoperative anatomic localization of a sentinel lymph node is possible in only two dimensions. To improve spatial localization of sentinel lymph nodes, a dual-head camera equipped with a transmission source was used to create combined transmission-emission SPECT images in a patient with a malignant melanoma of the left forearm. METHODS: Lymph node scintigraphy was performed after injection of Tc-99m-labeled nanocolloid around the tumor site 1 day before operation. SPECT was performed using a gamma camera equipped with a transmission collimator system originally designed to correct attenuation. Transmission and emission images were created simultaneously, matched, and displayed in three dimensions. RESULTS: In the combined emission-transmission images, the sentinel lymph node was clearly located in the left axilla. The lymph nodes could be identified during operation at the same location as that detected by SPECT. Based on preoperative information, the sentinel lymph node was identified rapidly and the extent and duration of the operation were minimized. CONCLUSIONS: This method provides better anatomic information, especially in deep structures such as the axilla or pelvis. With accurate three-dimensional preoperative information, intraoperative access is quicker and less invasive for the patient.

Aged↗
PubMed2003

Papulonodular mucinosis associated with subacute cutaneous lupus erythematosus.

Mucin deposition is a common histopathologic finding in lupus erythematosus (LE) but is rarely present in sufficient quantity to produce clinically apparent skin lesions. Until now, fewer than 40 cases of papulonodular mucinosis associated with LE have been reported in the literature, and it was associated with either systemic LE or discoid LE. For the first time, to our knowledge, we describe 2 patients with subacute cutaneous LE who presented with papulonodular mucinosis as a major clinical manifestation of their disease.

Adult↗
PubMed2003

Lupus erythematosus tumidus in childhood. Report of 3 patients.

Lupus erythematosus (LE) is a rare disorder in childhood. Most patients reported in the literature present with systemic manifestations, and, to date, fewer than 20 children with chronic cutaneous LE have been documented. In this article, we describe 3 patients with childhood LE tumidus, an uncommon but distinct subtype of chronic cutaneous LE. The lesions are characterized by erythematous, urticaria-like, nonscarring plaques in sun-exposed areas and, unlike in other variants of chronic cutaneous LE, there is no epidermal involvement. The clinical, photobiological, and histologic features as well as the differential diagnoses of childhood LE tumidus are discussed and compared with the adult form of this disease.

Child↗
PubMed2002

Characterization of the inflammatory infiltrate and expression of endothelial cell adhesion molecules in lupus erythematosus tumidus.

Lupus erythematosus tumidus (LET) is a disease with characteristic clinical and histopathologic features that has not always been considered a subset of cutaneous lupus erythematosus (CLE). Although LET was first mentioned in the literature in 1930, it has rarely been documented, and immunohistochemical studies have never been performed. The aim of the present study was to characterize the inflammatory infiltrate and to analyze the expression of endothelial cell adhesion molecules in skin specimens from patients with LET and to compare the results with those from patients with other variants of CLE, such as discoid lupus erythematosus (DLE) and subacute cutaneous lupus erythematosus (SCLE). Cryostat sections of lesional skin specimens from ten patients with LET demonstrated an infiltrate composed of more than 75% CD4+, CD8+, and HLA-DR+ cells. Interestingly, CD45RO+ cells, in contrast to CD45RA+ cells, were the prevailing inflammatory cell population. Compared with skin specimens from patients with DLE and SCLE, the mean expression of CD4+ and CD8+ cells was higher (but not significantly so) in LET, and no differences were observed with the other three antibodies. Furthermore, in contrast to controls, intercellular adhesion molecule-1, vascular adhesion molecule-1, E-selectin, and P-selectin showed the same expression pattern in skin specimens from patients with DLE, SCLE, and LET. In conclusion, the inflammatory infiltrate of LET primarily consists of CD4+/CD8+ lymphocytes. Furthermore, expression of endothelial cell adhesion molecules was equally upregulated in LET compared with the expression in DLE and SCLE, suggesting a similar immunopathomechanism of these subtypes of CLE.

Amine Oxidase (Copper-Containing)↗
PubMed2002

CCL27-CCR10 interactions regulate T cell-mediated skin inflammation.

The skin-associated chemokine CCL27 (also called CTACK, ALP and ESkine) and its receptor CCR10 (GPR-2) mediate chemotactic responses of skin-homing T cells in vitro. Here we report that most skin-infiltrating lymphocytes in patients suffering from psoriasis, atopic or allergic-contact dermatitis express CCR10. Epidermal basal keratinocytes produced CCL27 protein that bound to extracellular matrix, mediated adhesion and was displayed on the surface of dermal endothelial cells. Tumor necrosis factor-alpha and interleukin-1beta induced CCL27 production whereas the glucocorticosteroid clobetasol propionate suppressed it. Circulating skin-homing CLA+ T cells, dermal microvascular endothelial cells and fibroblasts expressed CCR10 on their cell surface. In vivo, intracutaneous CCL27 injection attracted lymphocytes and, conversely, neutralization of CCL27-CCR10 interactions impaired lymphocyte recruitment to the skin leading to the suppression of allergen-induced skin inflammation. Together, these findings indicate that CCL27-CCR10 interactions have a pivotal role in T cell-mediated skin inflammation.

Animals↗
PubMed2002

Methotrexate treatment for refractory subacute cutaneous lupus erythematosus.

Methotrexate is beneficial in rheumatoid arthritis and has been used in small studies of patients with systemic lupus erythematosus. We describe a patient with severe subacute cutaneous lupus erythematosus refractory to therapy with antimalarials and corticosteroids. Treatment with methotrexate resulted in complete clearing of the skin lesions without any side effects.

Adult↗