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It is likely that alopecia areata is a multifactorial disease determined by a combination of genetic and environmental factors. The interaction of susceptibility genes with environmental factors gives rise to the disease phenotype, and then genetic modifying factors determine the extent of the inflammatory response and thereby the clinical outcome. Cytokines regulate the inflammatory response. Polymorphisms in these genes may therefore determine the amount of a cytokine that is produced in response to an environmental trigger such as a bacterial or viral infection.

Background: Severe atopic dermatitis (AD) remains difficult to treat. Cyclosporine is effective in adults but has not previously been investigated in children with AD., Objective: The aims were to investigate the efficacy, safety, and tolerability of cyclosporine in severe refractory childhood AD., Methods: Subjects 2 to 16 years of age were treated for 6 weeks with cyclosporine, 5 mg/kg per day, in an open study. Disease activity was monitored every 2 weeks by means of sign scores, visual analogue scales for symptoms, and quality-of-life questionnaires. Adverse events were monitored. Efficacy and tolerability were assessed with five-point scales., Results: Twenty-seven children were treated. Significant improvements were seen in all measures of disease activity. Twenty-two showed marked improvement or total clearing. Quality of life improved for both the children and their families. Tolerability was considered good or very good in 25 subjects., Conclusion: Cyclosporine may offer an effective, safe, and well-tolerated short-term treatment option for children with severe AD.

Dermatitis herpetiformis is a chronic subepidermal vesicular autoimmune skin disease characterized by a strong association with the human leukocyte antigen A1-B8-DR3-DQ2 haplotype. Although the strongest major histocompatibility complex association has been shown to be with the DQw2 (DQB1*0201/DQA1*0501) heterodimer, recent evidence has suggested that there may be up to three susceptibility loci within the major histocompatibility complex. Tumor necrosis factor-alpha (TNF-alpha) is a cytokine with a broad range of proinflammatory, immunomodulating, and catabolic activities. We have recently described the first known polymorphism in the human TNF-alpha gene, which is biallelic and lies in the promoter region. The rare allele, TNF2, is in strong linkage disequilibrium with the human leukocyte antigen A1-B8-DR3-DQ2 haplotype. We therefore examined TNF-alpha genotypes in patients with dermatitis herpetiformis and controls and compared the association with that of the class II alleles. Although TNF2 is strongly associated with dermatitis herpetiformis, this was weaker than the association with the class II loci, with DQw2 (DQB1*0201/DQA1*0501) showing the strongest disease association. Of the four patients negative for this marker, only one carried the TNF2 allele. These results indicate that TNF2 is not a major disease susceptibility marker, although our results do not exclude a minor role.

Cytokines play key roles in immune responses, inflammation and fibrosis. The balance between levels of cytokines, their receptors and specific inhibitors controls inflammatory reactions in tissues. The pathogenesis of lichen sclerosus is unknown but probably involves cytokine mediators such as interleukin 1 (IL-1) and interleukin 1 receptor antagonist (IL-1ra). The IL-1ra is a competitive inhibitor of IL-1 alpha and IL-1 beta, and therefore is a powerful endogenous anti-inflammatory molecule. The gene encoding IL-1ra (designated IL-1RN) has a variable number tandem repeat polymorphism in intron 2. There are five alleles of the gene corresponding to 2, 3, 4, 5 and 6 repeats of an 86-bp sequence. We have determined allele frequencies in a control population and a group of 78 patients with lichen sclerosus. The frequency of one of the alleles is related to increasing disease severity. Thus, IL-1RN may be a candidate gene or severity factor for lichen sclerosus or may possibly be a linked marker to another, as yet undefined, gene.

Objective: We have previously described associations between an allele of the interleukin-1 receptor antagonist gene (IL1RN) and several inflammatory diseases. In this study we tested the IL1RN gene as a possible marker in patients with systemic lupus erythematosus (SLE)., Methods: Eighty-one SLE patients and 261 ethnically matched control subjects were genotyped by polymerase chain reaction., Results: We found an increase in both frequency and carriage rate of IL1RN*2 in the SLE group. This association strengthened with extensive disease and particularly with the presence of photosensitivity and discoid skin lesions., Conclusion: We describe a novel association between IL1RN*2 and SLE. Carriage of the allele seems to influence severity rather than susceptibility to SLE. We postulate that the association of this polymorphism with disease severity is a widespread feature of common inflammatory and autoimmune diseases.

One of the most potent pro-inflammatory mediators is the early-acting cytokine interleukin-1. Its actions are regulated by a structurally related anti-inflammatory cytokine known as the interleukin-1 receptor antagonist. We have previously characterized a DNA polymorphism in this gene (IL-1rn) and have found associations between allele 2 and several chronic inflammatory diseases. In the present study, we tested the frequency of allele 2 of the IL-1rn gene in 90 patients with alopecia areata compared with 261 healthy controls. There was a significant association between allele 2 of the polymorphism and the severity of alopecia areata. The frequency of allele 2 increased from 24.1% in the control population to 25.9% in patchy alopecia areata, 36.1% in alopecia totalis, and 47.2% in alopecia universalis (p = 0.005). This severity association is similar to that found in other epithelial-related diseases, including inflammatory bowel disease, lichen sclerosus, and systemic lupus erythematosus.

Normal murine bone marrow was incubated with medium conditioned by liver cells from human fetuses of 11-17 weeks gestational age. This treatment increased the proportion of murine haemopoietic stem cells (CFU-S) which were synthesizing DNA from less than 10% to more than 30%. The human fetal liver cell supernatants were fractionated using Amicon filters to obtain nominal molecular weight ranges of 10-30,000, 30-50,000 and 50-100,000 daltons. The stimulator was present only in the 30-50,000 dalton fraction. When human fetal liver cells were separated by adherence to plastic, medium conditioned by the adherent, but not the non-adherent, cells produced the stimulator. A population of non-cycling GM-CFC was not switched into cycle during incubation with this CFU-S proliferation stimulator. Human fetal livers of all gestational ages tested contain a specific stimulator of CFU-S proliferation. This appears to have properties similar to that demonstrated in murine fetal liver and regenerating murine bone marrow. Human and murine haemopoietic stem cell proliferation may therefore be regulated by similar mechanisms.