Andrea Szegedi

The complex role of vitamin D in autoimmune diseases.

Vitamin D, besides having well‐known control functions of calcium and phosphorus metabolism, bone formation and mineralization, also has a role in the maintenance of immune‐homeostasis. The immune‐regulatory role of vitamin D affects both the innate and adaptive immune system contributing to the immune‐tolerance of self‐structures. Impaired vitamin D supply/regulation, amongst other factors, leads to the development of autoimmune processes in animal models of various autoimmune diseases. The administration of vitamin D in these animals leads to improvement of immune‐mediated symptoms. Moreover, in human autoimmune diseases, such as multiple sclerosis, or rheumatoid arthritis the pathogenic role of vitamin D has been described. The review aims at describing the complex immune‐regulatory role of vitamin D from the cellular level through autoimmune animal models and depicting the known contribution of vitamin D in the pathogenesis of human autoimmune diseases.

Elevated rate of Thelper1 (TH1) lymphocytes and serum IFN-γ levels in psoriatic patients

Abstract Several disorders are known to be associated with altered Thelper1/Thelper2 (T H 1/T H 2) cytokine balance. Psoriasis is characterized by increased systemic and local production of T H 1 and pro-inflammatory cytokines. Furthermore recent data indicate the dominant presence of T H 1 lymphocytes in the circulation and T H 1 and Tcytotoxic1 (T C 1) cells in lesional skin of psoriatic patients. In order to assess the systemic T H 1/T H 2 imbalance in psoriasis most of the studies so far tested isolated peripheral mononuclear cells. As a new approach we applied a whole blood flow cytometric assay to determine the rate of circulating T H 1/T H 2 and T C 1/Tcytotoxic2 (T C 2) lymphocytes based on their intracellular IFN-γ, IL-4 and IL-10 expression. Besides, serum levels of these cytokines were determined in healthy controls and psoriatic patients by commercial ELISAs. In psoriatic patients we found significantly ( P + /IFN-γ + lymphocytes (30.3±8.8%) while the percent of CD4 + /IL-4 + cells (0.37±0.31%) were significantly ( P + /IFN-γ + : 20.1±7.3% and CD4 + /IL-4 + : 0.78±0.44%). The IL-10-positive CD4 + and CD8 + cells also had higher rate in psoriasis, but the difference between patients and controls was not significant, similarly to the rate of CD8 + /IFN-γ + and CD8 + /IL-4 + lymphocytes. Beside cellular expression, serum IFN-γ levels were also significantly higher (control: 4.9±6.4 pg/ml; psoriatic patients: 35.9±47.0 pg/ml; P H 1/T H 2 balance in psoriasis measured in non-separated whole blood T cells.

Peripheral blood gene expression patterns discriminate among chronic inflammatory diseases and healthy controls and identify novel targets

BackgroundChronic inflammatory diseases including inflammatory bowel disease (IBD; Crohns disease and ulcerative colitis), psoriasis and rheumatoid arthritis (RA) afflict millions of people worldwide, but their pathogenesis is still not well understood.It is also not well known if distinct changes in gene expression characterize these diseases and if these patterns can discriminate between diseased and control patients and/or stratify the disease. The main focus of our work was the identification of novel markers that overlap among the 3 diseases or discriminate them from each other.MethodsDiseased (n = 13, n = 15 and n = 12 in IBD, psoriasis and RA respectively) and healthy patients (n = 18) were recruited based on strict inclusion and exclusion criteria; peripheral blood samples were collected by clinicians (30 ml) in Venous Blood Vacuum Collection Tubes containing EDTA and peripheral blood mononuclear cells were separated by Ficoll gradient centrifugation. RNA was extracted using Trizol reagent. Gene expression data was obtained using TaqMan Low Density Array (TLDA) containing 96 genes that were selected by an algorithm and the statistical analyses were performed in Prism by using non-parametric Mann-Whitney U test (P-values < 0.05).ResultsHere we show that using a panel of 96 disease associated genes and measuring mRNA expression levels in peripheral blood derived mononuclear cells; we could identify disease-specific gene panels that separate each disease from healthy controls. In addition, a panel of five genes such as ADM, AQP9, CXCL2, IL10 and NAMPT discriminates between all samples from patients with chronic inflammation and healthy controls. We also found genes that stratify the diseases and separate different subtypes or different states of prognosis in each condition.ConclusionsThese findings and the identification of five universal markers of chronic inflammation suggest that these diseases have a common background in pathomechanism, but still can be separated by peripheral blood gene expression. Importantly, the identified genes can be associated with overlapping biological processes including changed inflammatory response. Gene panels based on such markers can play a major role in the development of personalized medicine, in monitoring disease progression and can lead to the identification of new potential drug targets in chronic inflammation.

Regulatory T cells in atopic dermatitis: epidermal dendritic cell clusters may contribute to their local expansion

Background  Regulatory T cells (Tregs) have an essential role in tolerance and immune regulation. However, few and controversial data have been published to date on the role and number of these cells in atopic dermatitis (AD).

Increased frequency of intracellular interleukin (IL)-13 and IL-10, but not IL-4, expressing CD4+ and CD8+ peripheral T cells of patients with atopic dermatitis.

Summary Background  A number of studies exist demonstrating the increased expression of type 2 cytokines and decreased capacity to produce interferon‐γ (IFN‐γ) in peripheral blood mononuclear cells (PBMCs) of patients with atopic dermatitis (AD).

Basophil CD63 expression assay on highly sensitized atopic donor leucocytes—a useful method in chronic autoimmune urticaria

Background  The autoimmune subclass of chronic idiopathic urticaria (CU) has been characterized by the occurrence of biologically relevant IgG antibodies against the IgE molecule or the α chain of the high‐affinity Fcɛ receptor (FcɛRIα) on basophils and mast cells. These antibodies are usually detected by autologous serum skin testing and confirmed by histamine release studies, immunoblotting, or enzyme‐linked immunosorbent assay, but not always.

Significant correlation between the CD63 assay and the histamine release assay in chronic urticaria

Background  Antibodies directed to the α subunit of the high affinity IgE receptor and the IgE molecule are proposed to be of pathogenetic relevance in a group of patients with chronic urticaria (CU). The diagnosis of autoimmune chronic urticaria (ACU) is difficult; the autologous serum skin test (ASST) seems to be a useful screening test, but reliable, additional confirmatory methods are needed.

Altered cytokine expression of peripheral blood lymphocytes in polymyositis and dermatomyositis

Objective: To investigate the intracellular and soluble cytokine levels and T cell subsets in peripheral blood of patients with active and inactive polymyositis and dermatomyositis. Methods: The frequencies of T and B lymphocytes, T helper (Th), and T cytotoxic (Tc) cells and of interferon γ (IFNγ), interleukin (IL)4, and IL10 expression of CD4+ or CD8+ cells were determined by flow cytometry. The concentrations of soluble cytokines were measured with commercial enzyme linked immunosorbent assays. Results: In active dermatomyositis there was a decreased percentage of T (CD3+) lymphocytes and Tc (CD8+) lymphocytes, decreased IFNγ expression of CD4+ and CD8+ cells, but an increase in B and IL4 producing CD4+ lymphocyte frequencies. These prominent changes disappeared in the inactive stage of the disease. In polymyositis no significant change in these lymphocyte subsets or in intracellular cytokine expression could be detected in either the active or the inactive form. The frequency of IL4+/IFNγ+ Th cells was calculated and a significantly increased Th2/Th1 frequency was found in active dermatomyositis, and a decreased frequency in inactive dermatomyositis, compared with the control population. Conclusions: There appears to be a difference between polymyositis and dermatomyositis in the level of peripheral blood lymphocytes and their intracellular cytokine content. These findings provide further evidence for a difference in the pathogenesis of polymyositis and dermatomyositis.

Immunological and Clinical Effects of Alphacalcidol in Patients with Psoriatic Arthropathy: Results of an Open, Follow-up Pilot Study

The aim of this study was to describe the effect of systemic alphacalcidol (1 OH vitamin D3) treatment on clinical and immunological parameters in patients with psoriatic arthropathy. Among the 19 patients investigated, 10 were treated with 0.25 microg oral alphacalcidol twice daily for 6 months, while 9 other patients served as controls. In the peripheral blood of the treated group but not in the controls, a statistically significant decrease was observed in the percentage of CD3/CD69-positive activated and CD8-positive interferon-gamma-producing T cells and in the serum level of interferon-gamma during the first 3 months and also in the clinical activity of the disease during the whole 6-month follow-up period. Our results show that systemic alphacalcidol treatment has an immunomodulatory effect on patients with psoriatic arthropathy. This effect is manifested by a short-term temporary decrease in type 1 immune responses and a continuous decrease in disease activity.

Multicentre study of fragrance allergy in Hungary. Immediate and late type reactions.

The authors followed the frequency of fragrance contact sensitization in Hungary in a multicentre study in the years 1998 and 1999. A total of 3604 patients were tested with fragrance mix (FM), and positive reactions were observed in 294 (8.2%). In 160 FM hypersensitive patients, the study was continued with patch testing of the mix constituents (cinnamic alcohol, cinnamic aldehyde, eugenol, amyl cinnamic aldehyde, hydroxycitronellal, geraniol, isoeugenol, oak moss absolute). Of the patients tested, 70.6% produced positive reactions to the constituents. FM contact sensitization was mainly observed in female patients (74.4%). The incidence of contact urticaria in FM hypersensitive patients was 6.1%. Simultaneous patch test trials of other environmental contact allergens, in both early and late evaluations, mainly confirmed hypersensitivity reactions to balsams. Female dominance of hypersensitivity reactions observed during testing the individual components of the mix was striking (82.4%). In positive skin reactions, cinnamic alcohol, isoeugenol and oak moss provoked skin symptoms most frequently. We also tested the 104 patients who produced negative reactions to FM with the constituent individual allergens, with 11.9% positive incidence. The clinical symptoms of the patients were above all manifest in the form of contact eczema, located on the hands, face, eyelids and axillae. With this study, the authors, members of the Hungarian Contact Dermatitis Research Group, call attention to one of the most frequent allergens in the environment.