Can serum cytokine profile discriminate irritant-induced and allergen-induced symptoms? A cross-sectional study in workers mostly exposed to laboratory animals

• Published in: Occupational and environmental medicine (London, England) Vol. 74; no. 8; pp. 592 - 600
• Main Authors: Lemaire, Muriel, Oppliger, Anne, Hotz, Philipp, Renauld, Jean-Christophe, Braun, Julia, Maggi, Marion, Barresi, Fabio, Schmid-Grendelmeier, Peter, Huaux, François, Dressel, Holger
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group Ltd 01.08.2017; BMJ Publishing Group LTD
• Subjects: Adolescent; Adult; Air pollution; Allergens; Allergies; Animal bites; Animals; Animals, Laboratory; Assaying; Asthma; Cluster analysis; Clustering; Cross-Sectional Studies; Cytokines; Cytokines - blood; Diagnosis; Disease prevention; Endotoxins; Eotaxin; Exposure; Female; Health surveillance; Humans; Hypersensitivity - blood; Hypersensitivity - epidemiology; Hypersensitivity - immunology; Immunoglobulin E; Immunoglobulin E - blood; Inflammation; Interleukin 13; Interleukin 22; Interleukin 5; Interleukin 8; Interleukins; Interleukins - blood; Interviews as Topic; Irritation; Laboratory animals; Laboratory tests; Male; Mice - immunology; Middle Aged; Molecular weight; Multiplexing; Occupational Diseases - epidemiology; Occupational Diseases - immunology; Occupational exposure; Occupational Exposure - adverse effects; Rats - immunology; Regression Analysis; Skin; Spirometry; Studies; Universities; Workers; Workplace; Young Adult; animal technicians; allergy; cytokines
• ISSN: 1351-0711; 1470-7926; 1470-7926
• DOI: 10.1136/oemed-2016-104137

BackgroundIn workers exposed mostly to laboratory animals (LA), symptoms may be due to irritants or allergens. Correct aetiological diagnosis is important for health surveillance.ObjectivesThis study aims to test whether work-related (WR) allergen-induced symptoms are associated with a cytokine profile distinct from that due to irritants.MethodsIn a cross-sectional study (n=114), WR respiratory and/or skin symptoms were assessed through a standardised clinical examination and sensitisation to rat and/or mouse allergen determined by serum immunoglobulin E. Serum cytokine concentrations were measured by multiplex assays. The predefined cytokine profiles ‘sensitiser’ (interleukin (IL)-4, IL-5, IL-13, eotaxin-1) and ‘irritation’ (IL-8, IL-17A, IL-17F, IL-22) were considered positive, when ≥3 concentrations exceeded the 95th percentile of the asymptomatic non-sensitised group. Results were examined by hierarchical clustering analyses (HCA) and multiple linear regression. Explorative analyses were carried out for nine additional cytokines. Exposure to allergens and endotoxin was assessed in a subpopulation.ResultsThe prevalence of the profile ‘irritation’ was comparable in 28 symptomatic non-sensitised workers and 71 asymptomatic non-sensitised workers. HCA showed that nearly all symptomatic non-sensitised workers were gathered in two subclusters, characterised by high IL-17A levels, but different IL-8 levels. Multiple linear regression identified drug consumption and current complaints as confounders. Sensitised subjects were too few (n=14) for testing the profile ‘sensitiser’.ConclusionsIn this unselected population of LA workers, the profile ‘irritation’ did not prove to be a valuable health surveillance tool. Low power precluded assessment of the profile ‘sensitiser’. The increased IL-17A concentration may originate from irritative constituents of organic dust.