The frequency of phospholipase A2 binding of basophilic granulocytes does not decrease during bee-venom-specific immunotherapy.

Background: The major allergenic component of bee venom is phospholipase A2 (PLA2).

Methods: In this study, PLA2 was used to analyze and enrich PLA2-binding cells from peripheral blood by high gradient magnetic cell sorting.

Results: In normal donors, the frequency of allergen (PLA2)-binding cells among peripheral blood mononuclear cells (PBMC) as determined by flow cytometry is below 0.

Correlation analysis between frequencies of circulating antigen-specific IgG-bearing memory B cells and serum titers of antigen-specific IgG.

Recent studies in mice have indicated that the long-lasting specific antibody responses seen after vaccination are probably due to the existence of long-lived plasma cells. Therefore, because the maintenance of humoral immunity does not necessarily reflect continuous restimulation of long-lived memory B cells, the question arises as to what degree antibody immunity, as determined by measuring serum immunoglobulin titers against a particular antigen, and memory B cell immunity, as determined by counting circulating memory B cells with specificity for that same antigen, correlate. Here, using a new assay combining two-step immunomagnetic enrichment with multiparameter flow cytometry to detect, enumerate and characterize antigen-specific memory B cells, we show for tetanus toxin C-fragment in blood of normal tetanus toxoid vaccinized donors, and for wasp venom phospholipase A1B in blood of wasp venom-allergic donors undergoing an immune therapy with wasp venom, that there is no statistically significant linear correlation between the frequencies of circulating antigen-specific IgG-bearing memory B cells and the serum titers of antigen-specific IgG.

Inhibition of allergic contact dermatitis to DNCB but not to oxazolone in interleukin-4-deficient mice.

The role of interleukin-4 as a regulator of immune responses in the skin is investigated with regard to the outcome of contact hypersensitivity reaction in interleukin-4-deficient BALB/C mice. In previous studies conflicting results were obtained concerning the role of interleukin-4 in contact hypersensitivity reactions supporting either a proinflammatory or rather an inhibitory function of this cytokine. Interleukin-4 deficient BALB/C mice sensitized to 2,4-dinitrochlorobenzene showed after challenge a significant reduction in magnitude and duration of the contact hypersensitivity response in comparison with wild-type mice.

Circulating type I collagen degradation products: a new serum marker for clinical severity in patients with scleroderma?

Systemic sclerosis (SSc; scleroderma) results in the excessive deposition of extracellular matrix components in affected organs. This is partly due to enhanced synthesis; however, the role of degradative processes in this disease is still poorly understood. Sera of 32 patients with SSc (22 with the diffuse, 10 with the limited form) and of six patients with morphoea were assessed using radioimmunoassays for the cross-linked carboxy terminal telopeptide of type I collagen (ICTP) and for the amino terminal propeptide of type I procollagen (PINP) reflecting type I collagen degradation and synthesis, respectively.

Immediate reaction to roxithromycin and prick test cross-sensitization to erythromycin and clarithromycin.

Allergic reactions to macrolides appear to be very rare. Only a few cases of fixed drug eruption or urticaria due to the administration of erythromycin have been reported. Cross-reaction between the different macrolides have not yet been published.

Systemic T-cell unresponsiveness during rush bee-venom immunotherapy.

By rush bee-venom immunotherapy, subjects reacting allergically to the venom can be effectively anergized, although the mechanism of action is not known. Here we analyzed the systemic effects of rush desensitization on the T cells of allergic patients. In most patients, we found reduced frequencies of T cells recalled to express CD69 and the cytokines interleukin (IL)-4 and interferon-gamma (IFN-gamma) after stimulation of peripheral blood mononuclear cells with phorbol 12-myristate 13-acetate (PMA) and ionomycin, as compared with normal donors.

Management of localized scleroderma.

Localized scleroderma denotes a spectrum of conditions characterized by circumscribed fibrotic areas involving different levels of the dermis, subcutis, and sometimes underlying soft tissue and bone. Although the clinical course of the disease is often benign, widespread lesions and disabling joint contractures may lead to significant complications. The pathogenesis of the different types of localized scleroderma is still unknown.

Bath-PUVA therapy in three patients with scleredema adultorum.

Background: Scleredema adultorum (SA) is a rare connective tissue disorder for which no treatment has proven to be effective.

Objective: Our purpose was to determine the effect of bath-PUVA therapy on SA.

Methods: Three patients were treated.

BM-40 (osteonectin, SPARC) is expressed both in the epidermal and in the dermal compartment of adult human skin.

BM-40 (Osteonectin, SPARC) is the most abundant glycoprotein secreted by human osteoblasts. In situ hybridization studies on the expression of BM-40 mRNA in murine tissues have demonstrated the highest levels of transcripts in bone, but expression was also observed in several other mesenchymal tissues. In contrast, little is known about the expression of BM-40 in human tissues, especially in skin.

Cutaneous adverse reaction to ciprofloxacin: demonstration of specific lymphocyte proliferation and cross-reactivity to ofloxacin in vitro.

Ciprofloxacin (CPFX) is a widely used fluoroquinolone antibiotic, inducing cutaneous adverse drug reactions in about 1 to 2% of the treated patients. Conclusive diagnosis of drug allergy, however, still remains a major problem in daily clinical practice. Here, we present 2 patients with drug allergy to CPFX.

Systemic scleroderma. Multicenter trial of 1 year of treatment with recombinant interferon gamma.

Objective: To confirm significant improvement of the skin score in systemic sclerosis by treatment with interferon gamma in a larger group of patients and to investigate on a molecular level the influence of interferon gamma on collagen type I messenger RNA expression.

Design: Open, noncontrolled multicenter study.

Setting: Five outpatient clinics specializing in the care of systemic scleroderma.

Double-blind, placebo-controlled study of intralesional interferon gamma for the treatment of localized scleroderma.

Background: Localized scleroderma is characterized by circumscribed fibrotic plaques and may progress to widespread skin involvement and fibrosis. Interferon gamma (IFN-gamma) has been shown to be a potent inhibitor of collagen synthesis and of the migration and proliferation of dermal fibroblasts.

Objective: Our purpose was to determine whether IFN-gamma is effective in the treatment of localized scleroderma.

Transforming growth factor-beta reverses deficient expression of type (I) collagen in cultured fibroblasts of a patient with metageria.

Metageria is a generalized form of acrogeria belonging to the group of premature aging syndromes and is characterized by loss of subcutaneous fat, thinning of the dermis, multiple teleangiectasias and mottled hyperpigmentation. The skin changes present suggest that an altered formation of extracellular matrix might be involved in the pathogenesis of this disease. Fibroblasts obtained from the skin of a patient with this disease revealed a marked reduction of type I collagen expression to about 20% of control levels both at the mRNA and protein level.

Co-ordinate induction of collagen type I and biglycan expression in keloids.

Proteoglycans are macromolecules displaying structural roles as well as regulatory functions in the maintenance of the extracellular matrix. Biglycan/PG-I and decorin/PG-II are two small proteoglycans that are structurally related but differ considerably in their localization in vivo and behaviour in vitro. Decorin and, to a minor extent, biglycan, can be located at the surface of type I collagen fibrils and have been shown to influence collagen fibrillogenesis.

Regulation of collagen expression by interleukin-1 beta is dependent on donor age.

Cultured skin fibroblasts derived from old (> 60 years) donors differ in various morphological and functional aspects from cells obtained from young (< 20 years) donors. We were interested in whether fibroblasts obtained from old and young donors differ in their cellular response to interleukin-1 beta, a cytokine which has been shown to affect the synthesis of extracellular matrix proteins in human dermal fibroblasts. Therefore the expression of interstitial collagen (type I), minor collagen (type VI) and interstitial collagenase genes was investigated, using fibroblasts derived from either old or young donors.

Quantitative analysis of alpha 1 (I) procollagen transcripts in vivo by competitive polymerase chain reaction.

Due to the limited amount of RNA obtainable from punch biopsies, few data exist on the human alpha 1 (I) procollagen mRNA steady state level in vivo. Therefore, we established a competitive PCR method to quantitate this mRNA in human biopsies. In our approach, the target template and the standard share the same sequence except for a 69 bp deletion, thus competing for the same primer pair and subsequently amplifying at the same rate.

Isolation and characterization of allergen-binding cells from normal and allergic donors.

Background: Flow cytometry of the immune system so far has been limited to the analysis of subpopulations according to lineage markers. The cells involved in a particular immune response could not be assayed due to their low frequency. Here we show the potential of antigen-specific high gradient magnetic cell sorting to enrich cells for visualisation in multiparameter cytometry, functional studies and immortalization.

Altered immunohistochemical expression of small proteoglycans in the tumor tissue and stroma of basal cell carcinoma.

Small proteoglycans have been shown to act as receptors for matrix molecules or growth factors and to influence the attachment and the migration of cells. We therefore report here on the immunocytochemical expression of three small proteoglycans, i.e.

Expression of type VI collagen mRNA during wound healing.

During the highly regulated process of wound healing the expression of the interstitial collagens I and III is increased in a time-dependent fashion. Although ultrastructural and in vitro studies suggest a physiologic role of collagen VI in the organization of extracellular matrix deposition, nothing is known about its role in wound healing. Therefore, we studied collagen VI gene expression during wound healing in humans compared to that of collagens I and III.