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1.
J Dermatol ; 51(5): 691-695, 2024 May.
Article En | MEDLINE | ID: mdl-38351529

Allergic contact dermatitis has been established as the most frequent cause of eyelid dermatitis, but it is often misdiagnosed. The purpose of this study was to evaluate the characteristics of patients with eyelid dermatitis who were referred for patch testing. The patients were divided into three subgroups in this retrospective study: patients with only eyelid involvement, patients with involvement of eyelids and other areas, and patients without eyelid involvement. Data was collected on diagnoses, medical history, personal care products and make-up use, occupational dermatitis, and positive allergens. An independent t-test, one-way ANOVA, and chi-squared test were used to analyze the data. A total of 427 patients who referred for patch tests were included in the study. Of these, 139 patients had eyelid dermatitis. Allergic contact dermatitis (ACD) was the most common diagnosis in all three groups referred for patch tests. Use of shaving cream and hair conditioner was significantly higher in patients with only eyelid involvement and nickel sulfate was the most common allergen among them. Patch testing is the gold standard tool in the evaluation of eyelid contact dermatitis, and it is a necessity in the treatment of eyelid dermatitis, for the accurate identification of responsible allergens.


Allergens , Dermatitis, Allergic Contact , Eyelid Diseases , Patch Tests , Humans , Retrospective Studies , Dermatitis, Allergic Contact/diagnosis , Dermatitis, Allergic Contact/immunology , Dermatitis, Allergic Contact/etiology , Male , Female , Adult , Middle Aged , Allergens/immunology , Allergens/adverse effects , Eyelid Diseases/diagnosis , Eyelid Diseases/immunology , Eyelid Diseases/etiology , Aged , Young Adult , Nickel/adverse effects , Nickel/immunology , Eyelids/pathology , Cosmetics/adverse effects
2.
Nutrients ; 13(8)2021 Aug 23.
Article En | MEDLINE | ID: mdl-34445054

BACKGROUND: Restrictions due to the COVID-19 pandemic limited patients' access to hospital care. The aims of this study were to assess dietary nutritional status, quality of life (QoL), and adherence to dietary therapy before and after 30-day personalized diet therapy through telenutrition tools in patients with systemic nickel allergic syndrome (SNAS). METHODS: Each SNAS patient underwent the following allergological procedures: (a) face-to-face visit (nutritional visit and QoL evaluation) with prescription of one out of five personalized and balanced dietary plans different for calorie intake, (b) video call visit for dietary evaluation and assessment of adherence to diet after 15 days, and (c) video call visit for dietary and QoL evaluation and assessment of adherence to diet therapy after 30 days (end of study). RESULTS: We enrolled 20 SNAS patients. After 15 and 30 days, we found a statistically significant improvement in anthropometric findings after diet therapy, a significant adherence rate to low-nickel diet (60% and 80%, respectively), and an improvement in QoL with an increase in almost all psychometric indices. CONCLUSIONS: Our study demonstrates that telenutrition can be a valid tool to monitor nutritional status and adherence to balanced low-Ni diet positively affecting QoL in SNAS patients during the COVID-19 pandemic.


COVID-19/epidemiology , Diet , Hypersensitivity/diet therapy , Nickel/immunology , Telemedicine/methods , Adult , Female , Food Hypersensitivity , Humans , Hypersensitivity/etiology , Hypersensitivity/immunology , Male , Middle Aged , Pandemics , Quality of Life , SARS-CoV-2/isolation & purification , Young Adult
4.
Front Immunol ; 12: 676048, 2021.
Article En | MEDLINE | ID: mdl-34305906

The binding of nickel by immune proteins can manifest as Type IV contact dermatitis (Ni-specific T cells mediated) and less frequently as Type I hypersensitivity with both mechanisms remaining unknown to date. Since there are reports of patients co-manifesting the two hypersensitivities, a common mechanism may underlie both the TCR and IgE nickel binding. Focusing on Trastuzumab and Pertuzumab IgE variants as serendipitous investigation models, we found Ni-NTA interactions independent of Her2 binding to be due to glutamine stretches. These stretches are both Ni-inducible and in fixed pockets at the antibody complementarity-determining regions (CDRs) and framework regions (FWRs) of both the antibody heavy and light chains with influence from the heavy chain constant region. Comparisons with TCRs structures revealed similar interactions, demonstrating the possible underlying mechanism in selecting for Ni-binding IgEs and TCRs respectively. With the elucidation of the interaction, future therapeutic antibodies could also be sagaciously engineered to utilize such nickel binding for biotechnological purposes.


Hypersensitivity/etiology , Immunoglobulin E/immunology , Nickel/immunology , Superantigens/immunology , Antibodies, Monoclonal, Humanized/chemistry , Complementarity Determining Regions , HEK293 Cells , Humans , Immunoglobulin E/chemistry , Immunoglobulin Heavy Chains/chemistry , Immunoglobulin Variable Region/chemistry , Nickel/chemistry , Receptors, Antigen, T-Cell/immunology , Trastuzumab/chemistry
5.
Int J Mol Sci ; 22(5)2021 Feb 28.
Article En | MEDLINE | ID: mdl-33670995

Nickel (Ni2+) is one of the most common allergens, affecting around 10-15% of the general population. As the demand for orthopedic implant surgery rises, the number of surgical revisions due to joint implant failure also increases. There is evidence that some patients develop joint failure due to an immune response to a component of the implant, and we have found that Ni2+ is an especially important cause. Hence, understanding the mechanisms by which Ni2+ allergy induces joint implant failure becomes a critical research question. The structural basis of Ni2+ activation of pathogenic T cells is still not clear. The purpose of this study was to characterize Ni2+-reactive T cell repertoires derived from the peripheral blood of joint failure patients due to Ni2+ sensitization using single-cell sequencing techniques. We stimulated the proliferation of Ni2+ -reactive T cells from two implant failure patients in vitro, and sorted them for single-cell VDJ sequencing (10× genomics). We identified 2650 productive V-J spanning pairs. Both TCR α chains and ß chains were enriched. TRBV18 usage is the highest in the P7 CD4+ population (18.1%), and TRBV5-1 usage is the highest in the P7 CD8+ population (12.1%). TRBV19 and TRBV20-1 segments are present in a high percentage of both P7 and P9 sequenced T cells. Remarkably, the alpha and beta chain combination of TRAV41-TRBV18 accounts for 13.5% of the CD4+ population of P7 patient. Compared to current Ni specific T cell repertoire studies of contact dermatitis, the Vα and Vß usages of these joint implant failure patients were different. This could be due to the different availability of self-peptides in these two different tissues. However, TRBV19 (Vß17) was among frequently used TCR ß chains, which are common in previous reports. This implies that some pathogenic T cells could be similar in Ni2+ hypersensitivities in skin and joints. The alignment of the TCR CDR3ß sequences showed a conserved glutamic acid (Glu) that could potentially interact with Ni2+. The study of these Ni2+ specific TCRs may shed light on the molecular mechanism of T cell activation by low molecular weight chemical haptens.


Haptens , Hypersensitivity/metabolism , Joint Prosthesis , Nickel/immunology , Prosthesis Failure/etiology , Receptors, Antigen, T-Cell/genetics , T-Lymphocytes/immunology , Female , Humans , Hypersensitivity/complications , Hypersensitivity/genetics , Hypersensitivity/immunology , Sequence Analysis, DNA , Single-Cell Analysis , T-Lymphocytes/metabolism , VDJ Exons/genetics
6.
Contact Dermatitis ; 85(1): 7-16, 2021 Jul.
Article En | MEDLINE | ID: mdl-33576045

BACKGROUND: Patch testing is the gold standard for identifying culprit allergens in allergic contact dermatitis; however, it is laborious and positive reactions are difficult to quantitate. Development of complementary in vitro tests is, therefore, of great importance. OBJECTIVES: This study aimed to improve the in vitro lymphocyte proliferation test (LPT) to detect allergic responses to nickel (Ni), cobalt (Co), and chromium (Cr). METHODS: Twenty-one metal allergic patients with a positive patch test to Ni (n=16), Co (n=8), and Cr (n=3) and 13 controls were included. All were tested by a flow cytometric LPT. RESULTS: Metal-reactive cells were identified as T helper (Th) cells with high expression of the memory marker CD45RO. Skin-homing (cutaneous lymphocyte-associated antigen positive [CLA+]) Ni-reactive memory Th (Thmem hi ) cells identified individuals with a positive patch test for Ni with 100% sensitivity (95% confidence interval [CI] 81%-100%) and 92% specificity (95% CI 67%-100%). Moreover, Co-specific Thmem hi cells expressing CCR6 identified patients with a positive patch test for Co with 63% sensitivity (95% CI 31%-86%) and 100% specificity (95% CI 77%-100%). In Cr allergic individuals, Cr-reactive Thmem hi cells tended to increased CLA and CCR6 expression. CONCLUSION: Metal-reactive Th cells with high expression of CD45RO and coexpression of CLA and CCR6 improved the LPT, making it an attractive supplement to the patch test.


Chromium/immunology , Cobalt/immunology , Dermatitis, Allergic Contact/diagnosis , Dermatitis, Allergic Contact/immunology , Nickel/immunology , T-Lymphocyte Subsets/immunology , Adult , Female , Flow Cytometry , Humans , Immunologic Memory , Male , Middle Aged , Patch Tests
7.
Int J Immunopathol Pharmacol ; 34: 2058738420974895, 2020.
Article En | MEDLINE | ID: mdl-33242297

Nickel (Ni), the main responsible for allergic contact dermatitis worldwide, is also involved in systemic condition called "Systemic Nickel Sulfate Allergy Syndrome (SNAS)." Likewise, IgE-mediated reactivity to Lipid Transfer Protein (LTP) represents the main cause of primary food allergy in adults of Mediterranean countries. We evaluated the prevalence of SNAS in LTP allergic patients and investigated patients' clinical features with double sensitization (LTP and Ni). A retrospective, single-center, observational study was conducted performing a complete allergological work-up including: (1) skin prick tests; (2) serum specific IgE for plant food allergens and rPru p3 (LTP); (3) patch test with 5% Ni sulfate in petrolatum. We enrolled 140 LTP allergic patients of which 36 patients (25.7% of sample) showed additional positivity to Ni patch test. Patients with double sensitization were more frequently females and reported fewer cutaneous symptoms. Higher values of sIgE for peach, apple, peanut, walnut, grain, corn, and garlic were found in LTP allergic patients, while higher values for hazelnut in the other subgroup. The prevalence of SNAS in the LTP allergic population is clinically relevant. Moreover, the clinical and immunological profiles of patients with double sensitization were different from patients monosensitized to LTP.


Antigens, Plant/adverse effects , Carrier Proteins/adverse effects , Food Hypersensitivity/epidemiology , Fruit/adverse effects , Hypersensitivity/epidemiology , Nickel/adverse effects , Plant Proteins/adverse effects , Adult , Antigens, Plant/immunology , Biomarkers/blood , Carrier Proteins/immunology , Female , Food Hypersensitivity/diagnosis , Food Hypersensitivity/immunology , Fruit/immunology , Humans , Hypersensitivity/diagnosis , Hypersensitivity/immunology , Immunoglobulin E/blood , Intradermal Tests , Italy/epidemiology , Male , Middle Aged , Nickel/immunology , Plant Proteins/immunology , Prevalence , Retrospective Studies , Risk Assessment , Risk Factors , Syndrome , Young Adult
8.
Sci Immunol ; 5(52)2020 10 16.
Article En | MEDLINE | ID: mdl-33067380

Adaptive features of natural killer (NK) cells have been reported in various species with different underlying mechanisms. It is unclear, however, which NK cell populations are capable of mounting antigen-specific recall responses and how such functions are regulated at the molecular level. Here, we identify and characterize a discrete population of CD49a+CD16- NK cells in the human liver that displays increased epigenetic potential to elicit memory responses and has the functional properties to exert antigen-specific immunity in the skin as an effector site. Integrated chromatin-based epigenetic and transcriptomic profiling revealed unique characteristics of hepatic CD49a+CD16- NK cells when compared with conventional CD49a-CD16+ NK cells, thereby defining active genomic regions and molecules underpinning distinct NK cell reactivity. In contrast to conventional NK cells, our results suggest that adaptive CD49a+CD16- NK cells are able to bypass the KIR receptor-ligand system upon antigen-specific stimulation. Furthermore, these cells were highly migratory toward chemokine gradients expressed in epicutaneous patch test lesions as an effector site of adaptive immune responses in the skin. These results define pathways operative in human antigen-specific adaptive NK cells and provide a roadmap for harnessing this NK cell subset for specific therapeutic or prophylactic vaccine strategies.


Adaptive Immunity/genetics , Dermatitis, Contact/immunology , Epigenesis, Genetic/immunology , Killer Cells, Natural/immunology , Lymphocyte Subsets/immunology , Adult , Aged , Aged, 80 and over , Biopsy , Cell Line, Tumor , Cell Separation , Dermatitis, Contact/genetics , Dermatitis, Contact/pathology , Female , Flow Cytometry , Humans , Integrin alpha1/metabolism , Killer Cells, Natural/metabolism , Liver/cytology , Lymphocyte Subsets/metabolism , Male , Middle Aged , Nickel/administration & dosage , Nickel/immunology , Patch Tests , Primary Cell Culture , RNA-Seq , Single-Cell Analysis , Skin/cytology , Skin/immunology , Skin/pathology
9.
Int Arch Allergy Immunol ; 181(6): 456-461, 2020.
Article En | MEDLINE | ID: mdl-32316004

BACKGROUND: The etiology of ulcerative colitis (UC) remains elusive even though many genetic and environmental pathogenic factors have been reported. Aberrant inflammatory responses mediated by specific subsets of T cells have been observed in ulcerative lesions of UC patients. OBJECTIVES: To elucidate the involvement of a delayed-type hypersensitivity reaction in UC, we focused on dental metal hypersensitivity, a T cell-mediated, delayed-type allergic reaction that causes oral contact mucositis and systemic cutaneous inflammation. METHOD: We recruited 65 Japanese UC patients and 22 healthy controls (HC) and used the in vitro lymphocyte stimulation test to quantify their sensitivity to zinc, gold, nickel, and palladium - the metals that have been widely used in dentistry. All subjects were users of metallic dental implants and/or prostheses containing zinc, gold, nickel, and/or palladium as major constituents. RESULTS: Sixty percent of the UC patients were hypersensitive to at least one metal species, whereas 32% of the HC were hypersensitive to only a single metal species. The overall incidence of metal hypersensitivity was significantly higher for UC patients than for HC. Furthermore, a significantly greater proportion of UC patients were hypersensitive to nickel or palladium. The severity of the sensitivity to nickel and palladium was also significantly greater for UC patients than for HC. CONCLUSIONS: This pilot study demonstrates that UC patients have a significantly higher incidence of hypersensitivity to nickel and palladium, suggesting the possible involvement of dental metal hypersensitivity in UC pathogenesis.


Colitis, Ulcerative/immunology , Dental Materials/adverse effects , Hypersensitivity, Delayed/complications , Nickel/immunology , Palladium/immunology , Adolescent , Adult , Aged , Case-Control Studies , Child , Female , Gold/adverse effects , Gold/immunology , Humans , Hypersensitivity, Delayed/chemically induced , Hypersensitivity, Delayed/diagnosis , Hypersensitivity, Delayed/epidemiology , Incidence , Male , Middle Aged , Nickel/adverse effects , Palladium/adverse effects , Pilot Projects , Prevalence , Young Adult , Zinc/adverse effects , Zinc/immunology
10.
Pediatrics ; 145(5)2020 05.
Article En | MEDLINE | ID: mdl-32341178

Nickel is a ubiquitous metal added to jewelry and metallic substances for its hardening properties and because it is inexpensive. Estimates suggest that at least 1.1 million children in the United States are sensitized to nickel. Nickel allergic contact dermatitis (Ni-ACD) is the most common cutaneous delayed-type hypersensitivity reaction worldwide. The incidence among children tested has almost quadrupled over the past 3 decades. The associated morbidities include itch, discomfort, school absence, and reduced quality of life. In adulthood, individuals with Ni-ACD may have severe disabling hand eczema. The increasing rate of Ni-ACD in children has been postulated to result from early and frequent exposure to metals with high amounts of nickel release (eg, as occurs with ear piercing or with products used daily in childhood such as toys, belt buckles, and electronics).To reduce exposure to metal sources with high nickel release by prolonged and direct contact with human skin, Denmark and the European Union legislated a directive several decades ago with the goal of reducing high nickel release and the incidence of Ni-ACD. Since then, there has been a global reduction in incidence of Ni-ACD in population-based studies of adults and studies of children and young adults being tested for allergic contact dermatitis. These data point to nickel exposure as a trigger for elicitation of Ni-ACD and, further, provide evidence that legislation can have a favorable effect on the economic and medical health of a population.This policy statement reviews the epidemiology, history, and appearances of Ni-ACD. Examples of sources of high nickel release are discussed to highlight how difficult it is to avoid this metal in modern daily lives. Treatments are outlined, and avoidance strategies are presented. Long-term epidemiological interventions are addressed. Advocacy for smarter nickel use is reviewed. The American Academy of Pediatrics supports US legislation that advances safety standards (as modeled by the European Union) that protect children from early and prolonged skin exposure to high-nickel-releasing items. Our final aim for this article is to aid the pediatric community in developing nickel-avoidance strategies on both individual and global levels.


Dermatitis, Allergic Contact/diagnosis , Dermatitis, Allergic Contact/therapy , Environmental Exposure/adverse effects , Nickel/adverse effects , Administration, Topical , Anti-Inflammatory Agents/administration & dosage , Dermatitis, Allergic Contact/immunology , Environmental Exposure/prevention & control , Humans , Nickel/immunology , Patch Tests/methods , Treatment Outcome
11.
Sci Rep ; 10(1): 5050, 2020 03 19.
Article En | MEDLINE | ID: mdl-32193426

Nickel (Ni) is the most frequent metal allergen and induces Th1-dependent type-IV allergies. In local skin, epidermal Langerhans cells (LCs) and/or dermal dendritic cells (DCs) uptake antigens and migrate to draining lymph nodes (LNs). However, the subsets of antigen-presenting cells that contribute to Ni presentation have not yet been identified. In this study, we analyzed the Ni-binding capabilities of murine DCs using fluorescent metal indicator Newport Green. Elicitation of Ni allergy was assessed after intradermal (i.d.) injection of Ni-treated DCs into ear pinnae of Ni-sensitized mice. The Ni-binding capabilities of MHC class IIhi CD11cint migratory DCs were significantly stronger than those of MHC class IIint CD11chi resident DCs and CD11cint PDCA1+ MHC class IIint B220+ plasmacytoid DCs. Migratory DCs in skin-draining and mandibular LNs showed significantly stronger Ni-binding capabilities than those in mesenteric and medial iliac LNs. An i.d. injection of IL-1ß induced the activation of LCs and dermal DCs with strong Ni-binding capabilities. Ni-binding LCs were detected in draining LNs after i.d. challenge with IL-1ß and Ni. Moreover, an i.d. injection of Ni-treated DCs purified from skin-draining LNs elicited Ni-allergic inflammation. These results demonstrated that migratory DCs in skin-draining LNs have strong Ni-binding capabilities and elicit Ni allergy.


Cell Movement/immunology , Dendritic Cells/immunology , Dermis/cytology , Nickel/immunology , Allergens/immunology , Animals , CD11 Antigens/immunology , Cells, Cultured , Dermis/immunology , Humans , Interleukin-1beta/immunology , Mice
12.
Nutrients ; 12(2)2020 Jan 28.
Article En | MEDLINE | ID: mdl-32012984

Alimentary nickel (Ni) may result in allergic contact mucositis (ACM), whose prevalence is >30% and may present with IBS-like and extra-intestinal symptoms. These symptoms are also frequent in endometriosis, and Ni allergic contact dermatitis has already been observed in endometriosis. Therefore, intestinal and extra-intestinal symptoms in endometriosis may depend on a Ni ACM, and a low-Ni diet could improve symptoms. We studied the prevalence of Ni ACM in endometriosis and focused on the effects of a low-Ni diet on gastrointestinal, extra-intestinal, and gynecological symptoms. We recruited 84 women with endometriosis, symptomatic for gastrointestinal disorders. Thirty-one out of 84 patients completed the study. They underwent Ni oral mucosa patch test (omPT), questionnaire for intestinal/extra-intestinal/gynecological symptoms, and a low-Ni diet. Clinical evaluation was performed at baseline (T0) and after three months (T1). Twenty-eight out 31 (90.3%) patients showed Ni omPT positive results, with Ni ACM diagnosis, whereas three out of 31 (9.7%) patients showed negative Ni omPT. After three months of low-Ni diet, all gastrointestinal, extra-intestinal and gynecological symptoms showed a statistically significant reduction. Ni ACM has a high prevalence in endometriosis and a low-Ni diet may be recommended in this condition to reduce gastrointestinal, extra-intestinal and gynecological symptoms.


Diet , Endometriosis/complications , Irritable Bowel Syndrome/complications , Nickel/immunology , Adult , Female , Humans , Irritable Bowel Syndrome/chemically induced , Irritable Bowel Syndrome/immunology , Middle Aged , Mucositis/chemically induced , Pilot Projects , Young Adult
15.
Front Immunol ; 10: 2758, 2019.
Article En | MEDLINE | ID: mdl-31827473

Delayed type hypersensitivity (DTH) reactions are considered infrequent complications in arthroplasty, but have been recognized to be associated with devastating morbidity and substantial decrease in quality of life of affected patients. Chronic inflammation of artificial joints and associated loss of peri-implant bone often require revision surgery. Methods for the diagnosis of implant-related DTH are available but infrequently considered to the full extent. Sequential diagnostics based on exclusion of septic complications, local and systemic metal level determination, lymphocyte transformation testing (LTT), and local T cell subset analysis are required for an unequivocal DTH diagnosis. Here, we report on a patient with a history of chronic rheumatoid arthritis and an unfavorable outcome of unilateral knee arthroplasty. This case illustrates pitfalls and difficulties in the course of recurrent inflammation following joint replacement. In the early course, suspicion of low-grade bacterial infection led to three two-stage revisions. Afterwards, the joint was proven to be sterile. However, metal level quantification revealed release of especially cobalt and chromium from the joint, LTT indicated persisting cobalt and nickel sensitization and subset analysis of T cells from the synovium suggested DTH as a root cause for the inflammatory symptoms. This report aims to recommend the depicted diagnostic algorithm as an adequate tool for future DTH detection. Yet, systemic to local subset ratios for effector memory and regulatory T cells should be derived from sufficient patient numbers to establish it as a diagnostic marker. Moreover, future prospects regarding implant-related DTH diagnostics are discussed. Therapeutic options for the portrayed patient are proposed, considering pharmaceutical, cell-therapeutic and surgical aspects. Patients who experience peri-implant inflammation but do not have obvious mechanical or infectious problems remain a diagnostic challenge and are at high risk of being treated inadequately. Since potentially sensitizing materials are regularly used in arthroplasty, it is essential to detect cases of acute DTH-derived inflammation of an artificial joint at early postoperative stages. This would reduce the severity of inflammation-related long-term consequences for affected patients and may avoid unnecessary revision surgery.


Arthritis, Rheumatoid/surgery , Hypersensitivity, Delayed/diagnosis , Hypersensitivity, Delayed/immunology , Metals/immunology , Aged , Arthritis, Rheumatoid/immunology , Arthroplasty, Replacement, Knee/adverse effects , Chromium/adverse effects , Chromium/immunology , Cobalt/adverse effects , Cobalt/immunology , Female , Humans , Knee/surgery , Knee Prosthesis/adverse effects , Metals/adverse effects , Nickel/adverse effects , Nickel/immunology , Reoperation , T-Lymphocytes/immunology
16.
BMC Dermatol ; 19(1): 10, 2019 07 10.
Article En | MEDLINE | ID: mdl-31291927

BACKGROUND: Patch testing with a baseline series is a common tool employed when the sensitizing agent in contact dermatitis is unclear. However, for Asian countries, there are no locally validated baseline series to utilize in screening. METHODS: We completed a retrospective analysis of all patients that had undergone patch testing with the European Baseline series, Shoe Series or Comprehensive International Baseline series, over 7 years from 2012 to 2018 in a tertiary care reference dermatology clinic in Sri Lanka to evaluate the suitability of these investigations to identify causes for contact dermatitis in the local study population. RESULTS: Out of 438 patients tested, 239 (54.8%) reacted to at least one substance in the series. The Shoe Series was significantly more likely to yield a positive result than the European Baseline Series (70.2% vs 46.9%, p < 0.05). The top three sensitizers identified by all series were nickel sulfate (16%, 70/438), p-phenylenediamine (12.3%, 54/438) and 2-mercaptobenzothiazole or mercapto mix (10.5%, 46/438). CONCLUSION: Shoe series has a comparatively high yield in the local population compared to European Baseline series. Since little less than half of the study population did not have any reactivity to any of the allergens tested it is important to develop or modify and validate a locally relevant, more suitable baseline series which is based on the Shoe Series in Sri Lanka. This is further evidence for the continuously changing nature of allergens in the environment and the need to modify existing patch testing standards accordingly.


Allergens/immunology , Dermatitis, Allergic Contact/diagnosis , Patch Tests/statistics & numerical data , Tertiary Care Centers/statistics & numerical data , Administration, Cutaneous , Adolescent , Adult , Aged , Aged, 80 and over , Allergens/administration & dosage , Benzothiazoles/administration & dosage , Benzothiazoles/immunology , Dermatitis, Allergic Contact/immunology , Female , Humans , Male , Middle Aged , Nickel/administration & dosage , Nickel/immunology , Patch Tests/standards , Phenylenediamines/administration & dosage , Phenylenediamines/immunology , Retrospective Studies , Sri Lanka , Tertiary Care Centers/standards , Young Adult
17.
Afr Health Sci ; 19(1): 1460-1466, 2019 Mar.
Article En | MEDLINE | ID: mdl-31148973

BACKGROUND: Persistent antigenic stimulation due to repeated exposure to nickel may lead to chronic inflammation resulting in allergic contact dermatitis (ACD). OBJECTIVES: This study was performed to assess nickel induced immune activation among patients sensitized against nickel. PATIENTS AND METHODS: A total of 35 patients (29 females and 6 males; mean age 36±9 years) with nickel contact dermatitis and 20 patch test negative healthy individuals (14 females and 6 males; mean age 29±7 years) were included in this study. Peripheral blood of patients and controls was incubated with nickel sulfate for 24 hours. Immune activation was assessed by CD69 up-regulation on T lymphocyte sub-sets by flow cytometry. RESULTS: Base line expression of CD69 on CD8+ lymphocytes was higher among patients compared to controls (4.1±1.3%vs2.8±1.1%;p<0.009). There was no difference in proportions of CD±CD69+ cells between patients and controls (3.2±0.9%vs2.3±0.8%). Exposure to nickel induced expression of CD69 on a significantly higher proportion of CD4+ lymphocytes (22.1±6.2%) of the ACD patients compared to controls (2.8±2.5%;p<0.0001). Similarly nickel induced CD69 expression on a higher proportion of CD8+ lymphocytes (18.2±5.3%) from ACD patients compared to the controls (1.9±1.8%;p<0.0006). CONCLUSION: CD69 molecule appears to be an important regulator of immune response in nickel contact dermatitis.


Antigens, CD/metabolism , Antigens, Differentiation, T-Lymphocyte/metabolism , CD4-Positive T-Lymphocytes/immunology , Dermatitis, Allergic Contact/immunology , Lectins, C-Type/metabolism , Nickel/adverse effects , Nickel/immunology , Adult , Allergens/immunology , CD4-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/immunology , Case-Control Studies , Dermatitis, Allergic Contact/diagnosis , Female , Flow Cytometry , Humans , Male , Middle Aged , Nickel/pharmacology , Patch Tests , Up-Regulation , Young Adult
18.
J Math Biol ; 79(2): 595-630, 2019 07.
Article En | MEDLINE | ID: mdl-31197444

Dermal exposure to metal allergens can lead to irritant and allergic contact dermatitis (ACD). In this paper we present a mathematical model of the absorption of metal ions, hexavalent chromium and nickel, into the viable epidermis and compare the localised irritant and T-lymphocyte (T-cell) mediated immune responses. The model accounts for the spatial-temporal variation of skin health, extra and intracellular allergen concentrations, innate immune cells, T-cells, cytokine signalling and lymph node activity up to about 6 days after contact with these metals; repair processes associated with withdrawal of exposure to both metals is not considered in the current model, being assumed secondary during the initial phases of exposure. Simulations of the resulting system of PDEs are studied in one-dimension, i.e. across skin depth, and three-dimensional scenarios with the aim of comparing the responses to the two ions in the cases of first contact (no T-cells initially present) and second contact (T-cells initially present). The results show that on continuous contact, chromium ions elicit stronger skin inflammation, but for nickel, subsequent re-exposure stimulates stronger responses due to an accumulation of cytotoxic T-cell mediated responses which characterise ACD. Furthermore, the surface area of contact to these metals has little effect on the speed of response, whilst sensitivity is predicted to increase with the thickness of skin. The modelling approach is generic and should be applicable to describe contact dermatitis from a wide range of allergens.


Allergens/immunology , Chromium/immunology , Dermatitis, Allergic Contact/immunology , Models, Biological , Nickel/immunology , Computer Simulation , Cytokines/immunology , Cytokines/metabolism , Humans , Immunity, Innate , Skin/cytology , Skin/immunology , Skin/metabolism , Spatio-Temporal Analysis , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/metabolism
19.
Contact Dermatitis ; 81(4): 254-261, 2019 Oct.
Article En | MEDLINE | ID: mdl-31198997

BACKGROUND: Reconstructed human epidermis (RhE) is widely used to replace animal models in order to assess the proinflammatory and allergenic effects of chemicals. Unfortunately, RhE lacks proinflammatory responsiveness for metal haptens, which are the most prevalent human contact allergens, raising concerns about its reliability for predicting skin allergens. OBJECTIVES: To investigate whether this limitation of RhE might be attributable to a lack of functional expression of Toll-like receptor 4 (TLR4), which governs proinflammatory sensitivity to nickel and cobalt. MATERIALS AND METHODS: RhE, dendritic cell (DC)-containing RhE and full-thickness skin equivalent (FTSE) were compared regarding their proinflammatory responsiveness to metal allergens. RESULTS: The incorporation of dermal fibroblasts was sufficient to confer metal sensitivity to RhE. Unlike keratinocytes, normal human fibroblasts expressed high levels of TLR4 mRNA and induced interleukin-8 expression upon stimulation with nickel or cobalt. Consistently, dermal isolates from FTSE expressed considerable amounts of TLR4 mRNA, whereas RhE or epidermis isolated from FTSE, normal human epidermis or inflamed human epidermis failed to express TLR4. Similarly, co-culture with TLR4-positive DCs bestowed RhE with proinflammatory responsiveness to metals. CONCLUSION: Our data suggest that FTSE or DC/RhE co-culture models can circumvent the shortcomings of RhE assays, and combine the benefits of complex and monoculture-based test systems in a single assay.


Dendritic Cells/metabolism , Fibroblasts/metabolism , Metals/immunology , Skin, Artificial , Skin/metabolism , Toll-Like Receptor 4/genetics , Cobalt/immunology , Coculture Techniques , Dermatitis, Allergic Contact/genetics , Dermatitis, Allergic Contact/metabolism , Humans , Inflammation/metabolism , Interleukin-8/metabolism , Keratinocytes/metabolism , Models, Biological , Nickel/immunology , RNA, Messenger/metabolism , Toll-Like Receptor 4/metabolism
20.
Contact Dermatitis ; 81(4): 227-241, 2019 Oct.
Article En | MEDLINE | ID: mdl-31140194

Nickel is the most frequent cause of contact allergy worldwide and has been studied extensively. This clinical review provides an updated overview of the epidemiology, exposure sources, methods for exposure quantification, skin deposition and penetration, immunology, diagnosis, thresholds for sensitization and elicitation, clinical pictures, prevention, and treatment. The implementation of a nickel regulation in Europe led to a decrease in the prevalence of nickel allergy, and changes in the clinical picture and disease severity. Nevertheless, the prevalences of nickel allergy in the European general population are approximately 8% to 19% in adults and 8% to 10% in children and adolescents, with a strong female predominance. Well-known consumer items such as jewellery and metal in clothing are still the main causes of nickel allergy and dermatitis, although a wide range of items for both private and occupational use may cause dermatitis. Allergic nickel dermatitis may be localized to the nickel exposure site, be more widespread, or present as hand eczema. Today, efficient methods for exposure quantification exist, and new insights regarding associated risk factors and immunological mechanisms underlying the disease have been obtained. Nevertheless, questions remain in relation to the pathogenesis, the persistent high prevalence, and the treatment of severe cases.


Dermatitis, Allergic Contact/etiology , Dermatitis, Allergic Contact/therapy , Nickel/adverse effects , Dermatitis, Allergic Contact/epidemiology , Dermatitis, Allergic Contact/immunology , Diet/adverse effects , Europe/epidemiology , Humans , Jewelry/adverse effects , Nickel/analysis , Nickel/immunology , Nickel/pharmacokinetics , Occupational Exposure/adverse effects , Patch Tests , Prevalence , Prostheses and Implants/adverse effects
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