Secretory leukocyte protease inhibitor regulates nerve reflex-mediated skin barrier function in psoriasis.

BACKGROUND: Secretory leukocyte protease inhibitor (SLPI), a ~12 kDa protein is an important regulator of innate and adaptive immunity and a component of tissue regenerative programmes. SLPI expression is markedly elevated in chronically inflamed skin, including that of individuals suffering from psoriasis. However, the role of SLPI in these diseases remains elusive. OBJECTIVES: The poor understanding of the early stages of the development of psoriasis is a major obstacle to successful intervention in the skin pathology. We hypothesized that SLPI and peripheral nerves that might be activated early in the progression of the disease likely form a functional relationship to maintain skin barrier homeostasis and respond to a variety of threats. METHODS: We used skin biopsies of healthy donors and individuals with psoriasis to show expression pattern of SLPI. A role of SLPI in psoriasis was mechanistically assessed using SLPI-deficient mice and an imiquimod (IMQ)-induced experimental model of psoriasis. RESULTS: We show that mice lacking SLPI had exaggerated skin alterations that extended beyond the treatment site in an imiquimod-induced psoriasis. The spatiotemporally distinct skin responses in SLPI-deficient mice, compared to their wild-type littermates, resulted from a compromised skin barrier function that manifested itself in heightened transepidermal water loss through the larger skin area surrounding the IMQ-challenged skin. The increased pathogenic skin changes in the absence of SLPI were reversible through pharmacological treatment that blocks a nerve-reflex arc. CONCLUSIONS: Together, these data indicate that SLPI plays a protective role in psoriasis through preventing skin dryness, inherent in the pathogenesis of psoriasis and that this SLPI action depends on neuronal input operating in a reflex manner. These findings reveal a previously unrecognized mechanism that maintains cutaneous homeostasis, which involves a crosstalk between the nervous system and a protein anatomically poised to fortify the epidermal permeability barrier.

In vitro drug causality assessment in Stevens-Johnson syndrome - alternatives for lymphocyte transformation test.

BACKGROUND: Patients with Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN) are often exposed simultaneously to a few potentially culprit drugs. However, both the standard lymphocyte transformation tests (LTT) with proliferation as the assay end-point as well as skin tests, if done, are often negative. OBJECTIVE: As provocation tests are considered too dangerous, there is an urgent need to identify the relevant drug in SJS/TEN and to improve sensitivity of tests able to identify the causative drug. METHODS: Fifteen patients with SJS/TEN with the ALDEN score ≥ 6 and 18 drug-exposed controls were included. Peripheral blood mononuclear cells (PBMC) were isolated and cultured under defined conditions with drugs. LTT was compared to the following end-points: cytokine levels in cell culture supernatant, number of granzyme B secreting cells by ELISpot and intracellular staining for granulysin and IFNγ in CD3(+) CD4(+), CD3(+) CD8(+) and NKp46(+) cells. To further enhance sensitivity, the effect of IL-7/IL-15 pre-incubation of PBMC was evaluated. RESULTS: Lymphocyte transformation tests was positive in only 4/15 patients (sensitivity 27%, CI: 8-55%). Similarly, with granzyme B-ELISpot culprit drugs were positive in 5/15 patients (sensitivity 33%, CI: 12-62%). The expression of granulysin was significantly induced in NKp46(+) and CD3(+) CD4(+) cells (sensitivity 40%, CI: 16-68% and 53%, CI: 27-79% respectively). Cytokine production could be demonstrated in 38%, CI: 14-68% and 43%, CI: 18-71% of patients for IL-2 and IL-5, respectively, and in 55%, CI: 23-83% for IFNγ. Pre-incubation with IL-7/IL-15 enhanced drug-specific response only in a few patients. Specificities of tested assays were in the range of 95 (CI: 80-99%)-100% (CI: 90-100%). CONCLUSIONS AND CLINICAL RELEVANCE: Granulysin expression in CD3(+) CD4(+) , Granzyme B-ELISpot and IFNγ production considered together provided a sensitivity of 80% (CI: 52-96%) and specificity of 95% (80-99%). Thus, this study demonstrated that combining different assays may be a feasible approach to identify the causative drug of SJS/TEN reactions; however, confirmation on another group of patients is necessary.

In vitro diagnosis of T cell-mediated drug allergy.

Diagnosis of drug hypersensitivity relies on history, skin tests, in vitro tests and provocation tests. In vitro tests are of great interest, due to possible reduction of drug provocation tests. In this review we focus on best investigated in vitro techniques for the diagnosis of T cell-mediated drug hypersensitivity reactions. As drug hypersensitivity relies on different pathomechanisms and as a single diagnostic test usually does not cover all possible reactions, it is advisable to combine different tests to increase the overall sensitivity. Recently, proliferation-based assays have been supplemented by a panel of novel in vitro tests including analysis of cytotoxic potential of effector cells (granzyme B, granulysin, CD107a), evaluation of cytokine secretion (IL-2, IL-5, IL-13, and IFN-γ) and up-regulation of cell surface activation markers (CD69). We discuss the latest findings and readout systems to identify causative drugs by detecting functional and phenotypic markers of drug-reacting cells, and their ability to enable a more conclusive diagnosis of drug allergy.

[Occupational allergic diseases in the steel industry. Population studies]. / Alergiczne choroby zawodowe w hutnictwie. Badania populacyjne.

The aim of this study was to evaluate the occurrence of occupational allergic diseases of the respiratory system and skin. The study was carried out in a population of 17,600 employees of Huta im. T. Sendzimira (T. Sendzimir Steelworks) in 1992-96. During this period 543 employees were referred to the Occupational Diseases Department with a suspection of occupational allergy. Connection between the kind of occupation and disease was confirmed in 215 cases. 104 (48%) suffered from upper respiratory tract diseases or bronchial asthma and 111 patients (52%) suffered from allergic skin disease as contact dermatitis of the hand or generalized dermatitis. The analysis showed that allergic skin diseases occurred more frequently in 1992-94 and allergenic respiratory diseases were more frequent in 1995-96. Industrial dust containing metals (nickel, chrome, iron, cooper) turned out to be the main allergic factor. The highest prevalence was observed in the Rolling-Mill Department, Chemistry of Coke Department and Incombustible Materials Department. 33% of patients suffering from allergic respiratory diseases and 10% suffering from allergic skin diseases had a family predisposition to allergy (features of atopy).