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T Rustemeyer

Publications and source records attributed to T Rustemeyer.

At least 19 recordsLinked to original sources

[Insulin allergy: background, diagnosis and treatment].

An allergic reaction develops in 2.4% of patients that use insulin. This ranges in severity from erythema and pruritus to life-threatening anaphylaxis. llergic reactions to insulin usually occur within a few hours after an injection and are usually due to a local or systemic type I IgE-mediated hypersensitivity reaction. Despite considerable research into the immunogenicity of insulin, this has not yet been clarified completely and allergic reactions to insulin still occur. A systematic diagnostic approach is essential for an adequate treatment plan. A blood test for anti-insulin antibodies and intradermal skin tests are of great importance. There are many options available for the treatment of insulin allergy and each patient must therefore be evaluated individually.

Anaphylaxis↗

CXCL8 secretion by dendritic cells predicts contact allergens from irritants.

Monocyte-derived dendritic cell functions have been explored for identification of contact allergens in vitro. Current methods, including measurement of changes in cell surface marker expression (e.g. CD83, CD86) do not provide a sensitive method for detecting the sensitising potential of a chemical. In this study, we investigated whether chemokine production by monocyte-derived dendritic cells is increased upon maturation and whether chemokine production can provide methodology for the detection of allergens. Monocyte-derived dendritic cells were exposed to allergens (nickel sulphate, cobalt chloride, palladium chloride, copper sulphate, chrome-(III)-chloride, potassium dichromate, p-phenylenediamine and dinitrochlorobenzene) and irritants (sodium dodecyl sulphate, dimethylsulphoxide, benzalkoniumchloride and propane-1-ol). CD83 and CD86 expression was analysed by flow cytometry and chemokine production (CXCL8, CCL5, CCL17, CCL18, CCL19, CCL20, CCL22) was determined by ELISA. Significant up regulation of CD83 and CD86 expression could only be induced by three out of seven and five out of seven allergens, respectively. In contrast, CXCL8 production was significantly increased after stimulation with all allergens tested, whereas irritant exposure led to decreased CXCL8 production. All other chemokines tested, failed in identifying contact allergens. In conclusion, CXCL8 production, next to CD83 and CD86 up regulation, by monocyte-derived dendritic cells provides a promising in vitro tool for discrimination between allergens and irritants.

Allergens↗

Regulation of nickel-induced T-cell responsiveness by CD4+CD25+ cells in contact allergic patients and healthy individuals.

In this study, we investigated the capacity of CD4+CD25+ regulatory T cells to suppress nickel-specific effector T cells, both in nickel-allergic patients and healthy controls. CD4+ cells isolated from allergic patients showed an increased proliferative response to nickel, whereas CD4+ cells from negative controls did not respond to allergen. When CD4+CD25+ cells were depleted, nickel-specific responsiveness was strongly increased both in allergic and in non-allergic individuals, with the most pronounced effect in allergic patients. These regulatory T cells were anergic to nickel but inhibited nickel-specific CD4+CD25- effector T cells in coculture experiments. CD4+CD25+ cells from nickel-allergic patients showed only a limited capacity to suppress effector T-cell responsiveness, because an increased nickel reactivity could still be detected in these cocultures. None of the isolated CD4+CD25+ cells, either isolated from healthy controls or allergic patients, produced IL-10 in response to nickel. Overall, these results support the view that CD4+CD25+ cells can control the activation of nickel-specific effector T cells in non-allergic individuals, whereas this regulatory capacity is impaired in allergic patients. To investigate the presence of allergen-specific regulatory T cells in truly naïve, non-sensitized individuals, T-cell reactivity should also be studied with non-environmental contact allergens, such as para-phenylenediamine.

CD4-Positive T-Lymphocytes↗

Induction of cytokine (interleukin-1alpha and tumor necrosis factor-alpha) and chemokine (CCL20, CCL27, and CXCL8) alarm signals after allergen and irritant exposure.

The immune system is called into action by alarm signals generated from injured tissues. We examined the nature of these alarm signals after exposure of skin residential cells to contact allergens (nickel sulfate and potassium dichromate) and a contact irritant [sodium dodecyl sulfate (SDS)]. Nickel sulfate, potassium dichromate, and SDS were applied topically to the stratum corneum of human skin equivalents. A similar concentration-dependent increase in chemokine (CCL20, CCL27, and CXCL8) secretion was observed for all three chemicals. Exposure to nickel sulfate and SDS was investigated in more detail: similar to chemokine secretion, no difference was observed in the time- and concentration-dependent increase in pro-inflammatory cytokine [interleukin-1alpha (IL-1alpha) and tumor necrosis factor-alpha (TNF-alpha)] secretion. Maximal increase in IL-1alpha secretion occurred within 2 h after exposure to both nickel sulfate and SDS and prior to increased chemokine secretion. TNF-alpha secretion was detectable 8 h after chemical exposure. After allergen or irritant exposure, increased CCL20 and CXCL8, but not CCL27, secretion was inhibited by neutralizing human antibodies to either IL-1alpha or TNF-alpha. Our data show that alarm signals consist of primary and secondary signals. IL-1alpha and TNF-alpha are released as primary alarm signals, which trigger the release of secondary chemokine (CCL20 and CXCL8) alarm signals. However, some chemokines, for example, CCL27 can be secreted in an IL-1alpha and TNF-alpha independent manner. Our data suggest that skin residential cells respond to both allergen and irritant exposure by releasing mediators that initiate infiltration of immune responsive cells into the skin.

Allergens↗

Nickel-responding T cells are CD4+ CLA+ CD45RO+ and express chemokine receptors CXCR3, CCR4 and CCR10.

BACKGROUND: Whereas T lymphocytes are widely accepted as effector cells determining the pathogenesis of allergic contact dermatitis, contradictory results have been found regarding the roles of different T-cell subsets. The use of various experimental models, involving long-term cultured T-cell lines or clones, may explain these contradictory results. OBJECTIVE: To investigate the involvement of distinct T-cell subsets in patients with nickel contact allergy. METHODS: Different T-cell subsets were directly isolated from peripheral blood mononuclear cells (PBMCs) of nickel-allergic patients, and their proliferative capacity, type-1 or type-2 cytokine secretion [measured by interferon (IFN)-gamma or interleukin (IL)-5 release] and phenotypical marker expression were analysed after stimulation with nickel. RESULTS: Only CD4+ CLA+ CD45RO+ and not CD8+ T cells proliferate and produce both type-1 (IFN-gamma) and type-2 (IL-5) cytokines in response to nickel. Moreover, cells expressing the marker CLA in combination with CD4, CD45RO or CD69 are increased after nickel-specific stimulation. Interestingly, in addition, CD45RA+ CLA+ cells showed an increased frequency after allergen-specific stimulation. Analysis of nickel-reactive T cells for expression of distinct chemokine receptors showed that both proliferative capacity and cytokine production are restricted to subsets expressing CXCR3, CCR4 but not CCR6. Fluorescence-activated cell sorting analysis of chemokine receptors expressed on nickel-stimulated T cells confirmed these results; a subset of T cells expressing CLA and CXCR3, CCR4 and, most importantly, CCR10 increased in response to allergen, while these CLA+ nickel-reactive T cells were all negative for CCR6. CONCLUSIONS: These findings demonstrate that freshly isolated nickel-reactive T cells can be characterized as CD4+ CLA+ memory T cells which express the chemokine receptors CXCR3, CCR4 and CCR10, but not CCR6.

Antigens, CD↗

Analysis of effector and regulatory immune reactivity to nickel.

BACKGROUND: Diagnostic patch testing in allergic contact dermatitis faces the risk of boosting existing hypersensitivities or active sensitization. Risk-free and reliable in vitro assays using peripheral blood are, therefore, wanted. OBJECTIVES: Here, we studied new approaches for in vitro monitoring of nickel-specific effector ad regulatory cell functions in allergic patients and potentially tolerized individuals. METHODS: Lymphocyte proliferation assays were carried out with the allergen and additional IL-12/IL-7 or IL-4/IL-7 cytokine supplements. Release of IFN-gamma and IL-5 were assessed as measures for type-1 and type-2 effector T cell function, respectively, and IL-10 and TGF-beta1 to monitor possible regulatory T cell function reflecting immunological tolerance. After optimization of in vitro cut-off values, potency of these parameters was evaluated as compared with conventional nickel patch testing. RESULTS: One hundred and fifty six outpatients were included in this study, 74 of whom presenting with a positive history of nickel allergy. Nickel-sulphate patch test results showed positive reactions in 43 patients, of whom 40 had a positive history (test sensitivity 54%; specificity 96%; overall accuracy 76%). Proliferation tests without cytokine supplementation showed an accuracy of 68%, which was further improved by supplementing IL-4/IL-7 (82%). IFN-gamma and IL-5 cytokine production, as revealed in IL-12/IL-7 and IL-4/IL-7 supplemented cultures, respectively, showed accuracies of 70% and 83%. As to the production of putatively immunoregulatory cytokines, IL-10 was most informative, with highest production rates in nickel-skin test negative individuals with long-lasting mucosal metal contact preceding skin piercing. CONCLUSIONS: These results indicate that measuring both T cell proliferation and cytokine secretion profiles, in particular IL-5 release using IL-4/IL-7 supplemented medium, offers a promising improvement of the in vitro diagnostic options in monitoring nickel contact sensitization. Since oral nickel contact has been shown earlier to induce active tolerization, nickel-induced in vitro IL-10 production may help identify nickel-tolerized individuals.

Adolescent↗

Identification of anti-inflammatory drugs according to their capacity to suppress type-1 and type-2 T cell profiles.

BACKGROUND: Down-regulation or modulation of T cell activity by immunosuppressive drugs is an effective treatment in diseases where exaggerated T cell responses play a role. A primary effect of the anti-inflammatory drugs (AIDs) is inhibition of the synthesis of growth factors, such as IL-2, thereby down-regulating T cell proliferation. However, it is still largely unknown to what extent these AIDs are able to down-regulate specifically type-1 or type-2 T cell cytokine production, and whether they can down-modulate chemokine receptor expression, thereby preventing migration of T cells to the site of inflammation. OBJECTIVE: We investigated the suppressive effect of dermatologically used AID (cyclosporin A (CsA), lactoferrin (LF), 1 alpha, 25-dihydroxyvitamin D(3) (VD(3)), hydrocortisone (HC), di-methyl-fumarate (DMF), diclofenac (DF)) on both type-1 and type-2 T cells. Since allergic contact dermatitis is a skin disorder in which an exaggerated T cell response of both types of T cell subsets can be observed, we used this disorder as a model to study the capacity of AID to suppress type-1 or type-2 T cell responses. METHODS: Peripheral blood mononuclear cells of nickel allergic patients were cultured in the presence of allergen and increasing concentrations of AID. Proliferation was determined by measuring (3)H thymidine incorporation; chemokine receptor (CCR10, CCR4, CXCR3) expression was studied by flow cytometric analysis and IFN-gamma or IL-5 cytokine production was measured by ELISA. RESULTS: Three major patterns can be distinguished regarding the effect of AID on T cell responses. The first group, including CsA and LF, inhibited non-selectively T cell proliferation, chemokine receptor expression and cytokine production, with CsA as the most potent drug tested. A second group of AID, which included VD(3), HC and DMF, suppressed mainly type-1 T cell responses, as revealed by strong interference with IFN-gamma production and CXCR3 expression, and limited effects on either or both IL-5 and CCR4 expression. The third pattern was displayed by DF, which down-regulated IL-5 production and CCR4 expression, whereas IFN-gamma and CXCR3 were unaltered. CONCLUSIONS: Using a contact allergy model, we have demonstrated that various AIDs show distinct pharmacological profiles in that either type-1 or type-2 or both T cell responses are suppressed. These results should contribute to a more rational selection of AID in treating inflammatory skin diseases mediated by either or both of these T cell subsets.

Anti-Inflammatory Agents↗

Comparison of two in vitro dendritic cell maturation models for screening contact sensitizers using a panel of methacrylates.

Allergen-induced emigration and maturation of dendritic cells (DC) are pivotal steps in sparking off allergic contact dermatitis. In vitro models, reflecting these steps, may provide tools for assessment of sensitizing capacities of putative contact allergens. Here, we evaluated the applicability of such models for a panel of methacrylate congeners, the sensitizing properties of which were established previously in clinical and experimental animal studies. First, using interleukin-4 (IL-4)/granulocyte-macrophage colony-stimulating factor (GM-CSF)-induced, blood monocyte-derived DC, hapten-induced up-regulation of maturation/ activation markers, including CD80, CD83, CD86, chemokine receptors CXCR4 and CCR5, as well as the drug resistance related molecules P-glycoprotein (Pgp) and lung resistance protein (LRP), were monitored by flow cytometry. Of note, whereas CD86 and CXCR4 were most sensitive in discriminating between the contact sensitizers and irritants included in the panel, i.e. sodium dodecyl sulphate (SDS) and croton oil (CO), assessment of CD83 and LRP expression reflected the relatively lower sensitizing capacity of methyl methacrylate. Second, using ex vivo skin explant cultures, allergen-induced LC migration from epidermal to basal membranous and dermal skin structures was most reliably monitored by CDla, as compared with Pgp, LRP, HLA-DR or CD54 staining. The extent of CD1a+ LC migration was found to closely correlate with the sensitizing capacities of the panel of test compounds. These results support the view that both in vitro models can provide valuable data on contact sensitizing properties, and add chemokine receptors and drug resistance related molecules to the list of DC membrane markers revealing allergenic signaling.

Cell Movement↗

Induction of tolerance and cross-tolerance to methacrylate contact sensitizers.

Induction of immunological tolerance to contact allergens might prevent undesired sensitization, in particular to occupational sensitizers, e.g., methacrylates (MA). Here, using a guinea pig model, we studied to which extent tolerance to one methacrylate might result in cross-tolerance to other congeners. Strong tolerance to the monomethacrylates hydroxy-ethyl MA (HEMA) and methyl MA, but not to the dimethacrylate ethylene-glycol MA (EGDMA) could be induced. The induced tolerance was stable, could not be broken by repeated sensitization attempts, and was mediated by specific suppressor cells, as demonstrated in T cell transfer experiments. In HEMA-tolerized animals, strong cross-tolerance to methacrylate congeners, including EGDMA, itself being nontolerogenic and showing the lowest cross-reactivity to HEMA, was found. Thus, oral application of contact allergens, to which skin contact cannot be avoided, e.g., in occupational settings, can induce broad cross-tolerance to related substances and might offer a promising preventive approach.

Allergens↗

Circulating V(alpha24+) Vbeta11+ NKT cell numbers are decreased in a wide variety of diseases that are characterized by autoreactive tissue damage.

Natural killer T (NKT) cells have been implicated as playing an important role in regulating immune responses. Defects in the NKT cell population were reported in animal autoimmune disease models and in distinct human autoimmune diseases. Here, we report that circulating V(alpha24+) Vbeta11+ NKT cell numbers are decreased in a broad variety of disorders with (auto)immune-mediated pathology, affecting the skin, bowel, central nervous system, and joints, regardless of disease duration or activity. Remarkably, normal circulating V(alpha24+) Vbeta11+ NKT cell numbers were found in Graves disease and coeliac disease. Since earlier studies noted a rise in NKT cells in myasthenia gravis, the picture emerges in which a defective NKT cell population is associated with autoreactive tissue damage rather than with the propensity to develop autoimmune disease. The present data support the idea that therapies aiming at the in vivo expansion of regulatory NKT cells might help to control immune-mediated damage in autoimmune disease.

Antigens, CD1↗

Human T lymphocyte priming in vitro by haptenated autologous dendritic cells.

Dendritic cells (DC), generated from adherent peripheral blood mononuclear cells (PBMC) by culturing with granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-4, were used to study in vitro sensitization of naive, hapten-specific T cells and to analyse cross-reactivities to related compounds. DC were hapten-derivatized with nickel sulphate (Ni) or 2-hydroxyethyl-methacrylate (HEMA), followed by tumour necrosis factor-alpha (TNF-alpha)-induced maturation, before autologous T cells and a cytokine cocktail of IL-1beta, IL-2 and IL-7 were added. After T cell priming for 7 days, wells were split and challenged for another 7 days with Ni or HEMA, and potentially cross-reactive haptens. Hapten-specificity of in vitro priming was demonstrated by proliferative responses to the haptens used for priming but not to the unrelated haptens. Highest priming efficiencies were obtained when both IL-4 and IL-12 were added to the cytokine supplement. Marked interferon-gamma (IFN-gamma) release (up to 4 ng/ml) was found when IL-12 was included in the cultures, whereas IL-5 release (up to 500 pg/ml) was observed after addition of IL-4 alone, or in combination with IL-12. Nickel-primed T cells showed frequent cross-reactivities with other metals closely positioned in the periodic table, i.e. palladium and copper, whereas HEMA-primed T cells showed distinct cross-reactivities with selected methacrylate congeners. Similar cross-reactivities are known to occur in allergic patients. Thus, in vitro T cell priming provides a promising tool for studying factors regulating cytokine synthesis, and cross-reactivity patterns of hapten-specific T cells.

Cells, Cultured↗

Contact allergy to calcipotriol does exist. Report of an unequivocal case and review of the literature.

A 64-year-old woman developed an itchy papulovesicular dermatitis at the periphery of psoriatic plaques on the lower legs after the daily application of calcipotriol ointment (Psorcutan Salbe) for 2 weeks. She had used the same ointment for 4 weeks 6 months before. Patch testing revealed strongly positive reactions to the marketed product and to the active ingredient calcipotriol in a concentration series (2.0, 10.0 and 50.0 microg/ml in isopropyl alcohol). A repeated open application test (ROAT) on the forearms showed a vesicular dermatitis after 4 days on the side that received the calcipotriol ointment, whereas the control with the placebo ointment remained completely negative. Histologic examination of the + + patch test reaction was in line with the picture of contact allergy. Retesting after 6 months confirmed the hypersensitivity, with a positive reaction even at 0.4 microg/ml. For comparison, the ROAT with calcipotriol ointment was performed for 2 weeks on both forearms of 15 volunteers never exposed to calcipotriol before. Only 2 subjects developed a slight reaction on days 5 and 11, respectively. Based on this case and on previous reports in the literature, calcipotriol must now be regarded as both a contact allergen and an irritant. For patch testing, a concentration of 2 microg/ml in isopropyl alcohol is the most suitable. If the reaction is only weakly positive and not reproducible after some time, it might be of the irritant type. In unclear cases, a ROAT should be performed. A severe papulovesicular dermatitis within 1 week will confirm the presence of contact allergy.

Administration, Cutaneous↗

Cross-reactivity patterns of contact-sensitizing methacrylates.

Methacrylates are well-known contact sensitizers with increasing frequency of contact leading to occupational skin disease. Here, we developed an animal model to facilitate studies on the sensitizing capacities and cross-reactivity patterns between four clinically most important allergens: methacrylate (MMA), 2-hydroxyethyl methacrylate (2-HEMA), 2-hydroxypropyl methacrylate (2-HPMA) and ethyleneglycol dimethacrylate (EGDMA). Inbred guinea pigs were immunized by ic injections of 300 microliters of 1.0 M methacrylate solutions in Freund's complete adjuvant into both flanks, both ears, and the neck. After 14 days open skin tests were performed with 50% MMA, 2-HEMA, or 2-HPMA or 10% EGDMA solutions in 40% DMSO in ethanol. Cross-reactivities were investigated 14 days later by skin testing with all four methacrylates. Using this newly developed protocol, strongly positive skin tests for methacrylates could be induced in almost all guinea pigs (MMA 26/26, 2-HEMA 16/18, 2-HPMA 15/16 and EGDMA 11/11). Whereas EGDMA induced only weak or infrequent cross-reactivities, 2-HEMA sensitization led to strong cross-reactions to all other methacrylates. Both MMA and 2-HPMA induced strong cross-reactivity to EGDMA but only weak to moderate reactivities to the other methacrylates. The absence of strong cross-reactions with monomethacrylates in EGDMA (dimethacrylate)-sensitized animals may be explained by the predominance of highly EGDMA-specific T-cells in these animals. In contrast, sensitization with MMA, 2-HEMA, and 2-HPMA would lead to recruitment of T-cells cross-reactive to the other monomethacrylates, according to their molecular similarities. The strong skin hypersensitivities observed for EGDMA in these latter groups are ascribed to enzymatic degradation into monomethacrylate compounds, notably 2-HEMA, at a rate sufficient to elicit cognate effector T-cells. The results of this study offer new insights in the development of methacrylate hypersensitivities and common cross-sensitization patterns in clinical practice.

Allergens↗

Contact allergies in healthcare workers. Results from the IVDK.

Healthcare workers often suffer from occupational skin disease frequently caused by allergic sensitization. Therefore the patch-test results and important patient history items of 31,849 patients recorded between 1992 and 1995 in the 24 allergy departments participating in the Information Network of Departments of Dermatology (IVDK) were evaluated. Significantly increased sensitization rates common to the healthcare sector as a whole were found for the vaccine preservative thiomersal (12.6% vs. 4.9%), the surface and instrument disinfectants glutardialdehyde (9.9% vs. 2.6%), formaldehyde (3.6% vs. 2.1%) and glyoxal (4.2% vs. 1.4%), and for the compounds of the thiuram mix (6.7% vs. 2.6%) present in protective gloves. Formaldehyde seems to lose its importance, but glyoxal must be added to the list of occupational allergens in the healthcare sector. In addition, occupation-specific sensitization was observed, with fragrances in massage therapists (16.1% vs. 10.6%) and nurses (13.8% vs. 11.4%), as well as with methacrylates in dental technicians. The often assumed importance of drugs as type-IV allergens was not confirmed, at least in terms of quantity. The identification of subgroups of increased risk and of occupation-specific allergens could be the basis of targeted preventive action in the healthcare sector.

Adult↗

Tree-pollen allergy is efficiently treated by short-term immunotherapy (STI) with seven preseasonal injections of molecular standardized allergens.

The efficacy and tolerance of short-term immunotherapy (STI) by seven preseasonal injections of tree-pollen allergens (ALK7 Frühblühermischung) was investigated in a double-blind, placebo-controlled, multicenter study with 111 rhinoconjunctivitis patients. Nasal and bronchial symptoms simultaneously analyzed, and nasal symptoms as a single end point, but not the overall score of nasal, bronchial, and conjunctival symptoms, showed a significantly lower increase with STI during birch-pollen exposure (both P=0.033, n=105, Mann-Whitney U-test). However, a selective analysis with patients from centers with high recruitment figures (n> or =10 patients, n=29 STI, n=32 placebo) showed a significantly lower increase of nasal, bronchial, and overall symptom score (STI 11.0 vs placebo 18.0, P=0.001, U-test). STI had equidirected effects on conjunctival, nasal, and bronchial symptoms analyzed as multiple end points, although conjunctival symptoms were not significantly different as a single end point. The seasonal increase in drug use was reduced by 62% in the STI group compared with placebo (P=0.032, t-test). Specific IgG4 increased only after STI (P<0.001); IgE was not significantly different. Eosinophil cationic protein remained unchanged with STI, but significantly increased with placebo in the pollen season (P=0.003). STI was well tolerated. In conclusion, STI was shown to be efficacious and safe for the treatment of patients with tree-pollen rhinoconjunctivitis.

Adolescent↗