PubMed Health⌕ Search

Biomedical subjects

Johannes M Weiss

Publications and source records attributed to Johannes M Weiss.

5 recordsLinked to original sources
PubMed2006

[Post-marketing surveillance on treatment of 5,665 patients with atopic dermatitis using the calcineurin inhibitor pimecrolimus: positive effects on major symptoms of atopic dermatitis and on quality of life].

BACKGROUND: Topical application of the calcineurin inhibitors pimecrolimus and tacrolimus is a current major advance in the therapy of atopic dermatitis. The aims of this post-marketing surveillance were: a) to acquire data on the efficacy and tolerability of pimecrolimus ointment (Elidel) on a very large cohort of patients from outpatient clinics, and b) to assess changes in their quality of life, a parameter not often considered in previous studies. PATIENTS AND METHODS: Included were 5,665 patients with atopic dermatitis. During the observation period, data on efficacy and tolerability were obtained at the beginning of the study, 3 to 10 days after initiation of therapy and after 4 to 6 weeks. Evaluation of symptoms as well as assessment of efficacy and tolerability were based on linear scales and on the percentage of the body surface area (% BSA) involved. Quality of life was assessed by the German version of the "Dermatology Life Quality Index (DLQI)" or the "Children's Dermatology Life Quality Index (CDLQI)". RESULTS: In this largest post-marketing surveillance hitherto performed in Germany, the efficacy of pimecrolimus was judged as "good" by 79.3 % of physicians and by 76.5 % of patients. Tolerability was assessed as "good" by 87.2 % of physicians and by 83.1 % of patients. Major symptoms of atopic dermatitis such as pruritus, erythema or lichenification showed marked reduction after just 3 to 10 days, signalling general improvement of the skin disease. In addition, application of pimecrolimus resulted in a significant improvement of the quality of life scores in both children and adults. CONCLUSION: The present study demonstrates that the good efficacy and tolerability of pimecrolimus ointment which had been shown in controlled trials: i) could also be demonstrated on a very large cohort of patients with atopic dermatitis when used in the outpatient setting, and ii) were paralleled by a significant improvement in the quality of life.

Adolescent↗
PubMed2005

Osteopontin functionally activates dendritic cells and induces their differentiation toward a Th1-polarizing phenotype.

Osteopontin (OPN) has been shown to have T helper 1 (Th1) cytokine functions in cell-mediated immunity. Deficiency of OPN is linked to a reduced Th1 immune response in autoimmunity, infectious disease, and delayed-type allergy. Dendritic cells (DCs) are central for the induction of T-cell-mediated immunity, when initially flexible DCs are instructed by priming signals and tissue-derived factors to adopt Th1, Th2, or regulatory T-cell-inducing phenotypes. Although OPN influences the cytokine secretion of T cells and macrophages, its effects on DC polarization remain an important missing link in the understanding of OPN functions in Th1 immunity. Here we demonstrate that OPN promotes the emigration of human DCs from the epidermis and functionally activates myeloid-type DCs, augmenting their expression of HLA-DR, costimulatory, and adhesion molecules. OPN induces their Th1-promoting tumor necrosis factor alpha (TNF-alpha) and interleukin-12 (IL-12) secretion, and enhances their allostimulatory capacity. In mixed lymphocyte reactions (MLRs), OPN stimulates IL-12 secretion by DCs, inducing elevated interferon-gamma (IFN-gamma) production by T cells. Naive Th cells stimulated by OPN-activated DCs show a Th1-polarized cytokine production. Our findings identify OPN as an important tissue-derived factor that DCs encounter when traveling from peripheral sites of activation to secondary lymphatic organs, which induces DC maturation toward a Th1-promoting phenotype.

Cell Differentiation↗
PubMed2005

Solitary cutaneous dendritic cell tumor in a child: role of dendritic cell markers for the diagnosis of skin Langerhans cell histiocytosis.

We describe a child with a solitary dendritic cell (DC) tumor positive for S-100 protein, CD1a, and HLA-DR with the clinical and histopathologic features of a so-called solitary variant of congenital self-healing Hashimoto-Pritzker reticulohistiocytosis (CSHRH). CSHRH is a spontaneously regressing, benign form of Langerhans cell histiocytosis (LCH) and was thought to be a histiocytosis consisting of precursor Langerhans cells. In our study the tumor cells did not express CD68, indicating that they represent mature DCs. Because of the negative finding for Langerin, it cannot be assessed whether the tumor consists of terminally mature Langerhans cells that have lost Langerin expression upon maturation or of mature dermal DCs. This case demonstrates that the progress in DC biology necessitates reevaluation of our knowledge of LCH to better understand the different variants of the disease. Therefore the literature on CSHRH is reviewed in light of present knowledge on cutaneous DC immunology.

Dendritic Cells↗
PubMed2004

Effect of osteopontin alleles on beta-glucan-induced granuloma formation in the mouse liver.

The granuloma formation is a host defense response against persistent irritants. Osteopontin is centrally involved in the formation of granulomas. Three osteopontin alleles, designated a, b, and c, have been found in mice. Here we used a murine model of zymosan (beta-glucan)-induced granuloma formation in the liver to determine possible functional differences between the osteopontin alleles in cell-mediated immunity. In contrast to mice with alleles a or c, mice with the allele b was defective in granuloma formation. As detected by mRNA expression, cytokines and chemokines known to be critically involved in granuloma formation were elicited in liver tissue, regardless of the osteopontin allele expressed. Alignment of the deduced amino acid sequences showed that unlike osteopontin c, b differs from a in 11 amino acids. All three osteopontin alleles had normal cell-binding properties. However, only the b allelic form was defective in the induction of cell migration as tested with dendritic cells. In conclusion, generation of a granulomatous response in mice depends critically on the presence of a functional osteopontin allele. Defective granuloma formation in mice with allele b is likely to be because of an impaired chemotactic function of the osteopontin b protein on immunocompetent cells.

Alleles↗