Characterization of fungal exposure and dectin-1 expression in healthy horses and horses with severe asthma.
Abstract: To quantify dectin-1 expression in bronchoalveolar lavage fluid (BALF), create polyclonal antibodies against equine dectin-1 and localize it in tissues, and quantify fungal exposure in pastured and stabled asthmatic and nonasthmatic horses. Methods: BALF samples from 6 controls and 6 horses with severe asthma. Stored lung and nasal wash samples. Methods: Dectin-1 expression was quantified by quantitative PCR (qPCR). Purified peptide from equine dectin-1 was used to generate polyclonal antibodies and was confirmed with immunological testing. Fungal exposure was quantified in BALF samples by counting fungal-like intracellular particles in phagocytic cells, by qPCR quantification of the "universal" 18S rRNA fungal gene, and by quantifying 36 specific fungi in equine and dust samples using qPCR assays. Results: Equine dectin-1 was localized in tissues and cells, and functional isoforms were upregulated significantly in BALF after stabling. Pastured horses from both groups had low levels of fungi in BALF, and there was a significant increase in some specific fungi, most notably for Eurotium amstelodami, Wallemia sebi, and Aspergillus niger after stabling. However, stabled asthmatic horses had fewer phagocytized particles, less 18S rRNA signal, and fewer specific fungi compared to nonasthmatic horses. Conclusions: Stabling increases exposure to fungi, but asthmatic horses had fewer fungi reaching their lower airways, presumably resulting from congestion and narrowing of the airways. Exposure to fungi could contribute to airway inflammation by increasing dectin-1 functional isoforms, and exposure to indoor molds should be avoided.
Publication Date: 2022-05-08 PubMed ID: 35524958PubMed Central: PMC9237812DOI: 10.2460/ajvr.21.09.0143Google Scholar: Lookup
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Summary
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This study investigates the levels of fungi exposure and the expression of immune receptor dectin-1 in healthy and asthmatic horses. The findings suggest stabling increases exposure to fungi, which may lead to higher inflammation in the airways through the increased expression of dectin-1. Asthmatic horses, however, appear to have fewer fungi reaching their lower airways, assumedly because of blockage and airway narrowing.
Research Methodology
- The researchers evaluated the levels of dectin-1, a protein that recognizes and helps fight off fungal infections, by analyzing bronchoalveolar lavage fluid (BALF) samples. They used samples from six healthy horses and six horses with severe asthma.
- Quantitative PCR (qPCR) was utilized to quantify dectin-1 expression, and antibodies against equine dectin-1 were generated using purified peptide to confirm its location at the tissue level.
- Fungal exposure in horses was determined by counting fungal particles in the phagocytic cells of BALF samples, quantifying the universally-present 18S rRNA fungal gene with qPCR, and assessing the presence of 36 specific fungi in horse and dust samples through qPCR assays.
Results
- The results revealed that dectin-1 was localized inside cells and tissues. The protein’s functional isoforms increased significantly in BALF samples after the horses were stabled.
- Low levels of fungi were found in the BALF samples from pastured horses, regardless of their health status. However, stabling considerably increased their exposure to certain fungi strains, particularly Eurotium amstelodami, Wallemia sebi, and Aspergillus niger.
- In comparison to healthy horses, fewer fungal particles, less 18S rRNA signal, and fewer specific fungi were found in asthmatic horses’ stabled conditions.
Conclusions
- The findings show that keeping horses in stables results in higher fungal exposure, although asthmatic horses show fewer fungi reaching their lower airways due to suspected congestion and narrowing of the airways.
- The increased exposure to fungi may lead to elevated airway inflammation via the increased expression of functional dectin-1 isoforms.
- The researchers concluded that exposure to indoor molds should be avoided to decrease the risk of airway inflammation.
Cite This Article
APA
Di Pietro R, Dubuc V, Manguin E, Giroux-Lafond R, Bédard C, Boivin R, Lavoie JP, Vesper SJ, Leclere M.
(2022).
Characterization of fungal exposure and dectin-1 expression in healthy horses and horses with severe asthma.
Am J Vet Res, 83(6), ajvr.21.09.0143.
https://doi.org/10.2460/ajvr.21.09.0143 Publication
Researcher Affiliations
- Department of Clinical Sciences, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada.
- Department of Clinical Sciences, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada.
- Department of Clinical Sciences, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada.
- Department of Clinical Sciences, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada.
- Department of Pathology and Microbiology, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada.
- Department of Clinical Sciences, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada.
- Department of Clinical Sciences, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada.
- Center for Environmental Measurement and Modeling, U.S. Environmental Protection Agency, Cincinnati, OH.
- Department of Clinical Sciences, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada.
MeSH Terms
- Animals
- Asthma / veterinary
- Bronchoalveolar Lavage Fluid
- Horse Diseases
- Horses
- Lectins, C-Type
- RNA, Ribosomal, 18S
Grant Funding
- EPA999999 / Intramural EPA
References
This article includes 50 references
- Couëtil LL, Cardwell JM, Gerber V, Lavoie JP, Léguillette R, Richard EA. Inflammatory Airway Disease of Horses--Revised Consensus Statement.. J Vet Intern Med 2016 Mar-Apr;30(2):503-15.
- White S, Moore-Colyer M, Marti E, Coüetil L, Hannant D, Richard EA, Alcocer M. Development of a comprehensive protein microarray for immunoglobulin E profiling in horses with severe asthma.. J Vet Intern Med 2019 Sep;33(5):2327-2335.
- Akar-Ghibril N, Casale T, Custovic A, Phipatanakul W. Allergic Endotypes and Phenotypes of Asthma.. J Allergy Clin Immunol Pract 2020 Feb;8(2):429-440.
- Dauvillier J, Ter Woort F, van Erck-Westergren E. Fungi in respiratory samples of horses with inflammatory airway disease.. J Vet Intern Med 2019 Mar;33(2):968-975.
- Vrins A, Doucet M, Nunez-Ochoa L. A retrospective study of bronchoalveolar lavage cytology in horses with clinical findings of small airway disease.. Zentralbl Veterinarmed A 1991 Jul;38(6):472-9.
- Schmallenbach KH, Rahman I, Sasse HH, Dixon PM, Halliwell RE, McGorum BC, Crameri R, Miller HR. Studies on pulmonary and systemic Aspergillus fumigatus-specific IgE and IgG antibodies in horses affected with chronic obstructive pulmonary disease (COPD).. Vet Immunol Immunopathol 1998 Dec 11;66(3-4):245-56.
- Eder C, Crameri R, Mayer C, Eicher R, Straub R, Gerber H, Lazary S, Marti E. Allergen-specific IgE levels against crude mould and storage mite extracts and recombinant mould allergens in sera from horses affected with chronic bronchitis.. Vet Immunol Immunopathol 2000 Mar 15;73(3-4):241-53.
- Künzle F, Gerber V, Van Der Haegen A, Wampfler B, Straub R, Marti E. IgE-bearing cells in bronchoalveolar lavage fluid and allergen-specific IgE levels in sera from RAO-affected horses.. J Vet Med A Physiol Pathol Clin Med 2007 Feb;54(1):40-7.
- Morán G, Folch H, Araya O, Burgos R, Barria M. Detection of reaginic antibodies against Faenia rectivirgula from the serum of horses affected with Recurrent Airway Obstruction by an in vitro bioassay.. Vet Res Commun 2010 Dec;34(8):719-26.
- Halliwell RE, McGorum BC, Irving P, Dixon PM. Local and systemic antibody production in horses affected with chronic obstructive pulmonary disease.. Vet Immunol Immunopathol 1993 Oct;38(3-4):201-15.
- Reponen T, Vesper S, Levin L, Johansson E, Ryan P, Burkle J, Grinshpun SA, Zheng S, Bernstein DI, Lockey J, Villareal M, Khurana Hershey GK, LeMasters G. High environmental relative moldiness index during infancy as a predictor of asthma at 7 years of age.. Ann Allergy Asthma Immunol 2011 Aug;107(2):120-6.
- Zhang Z, Biagini Myers JM, Brandt EB, Ryan PH, Lindsey M, Mintz-Cole RA, Reponen T, Vesper SJ, Forde F, Ruff B, Bass SA, LeMasters GK, Bernstein DI, Lockey J, Budelsky AL, Khurana Hershey GK. β-Glucan exacerbates allergic asthma independent of fungal sensitization and promotes steroid-resistant T(H)2/T(H)17 responses.. J Allergy Clin Immunol 2017 Jan;139(1):54-65.e8.
- Douwes J. (1-->3)-Beta-D-glucans and respiratory health: a review of the scientific evidence.. Indoor Air 2005 Jun;15(3):160-9.
- Ariizumi K, Shen GL, Shikano S, Xu S, Ritter R 3rd, Kumamoto T, Edelbaum D, Morita A, Bergstresser PR, Takashima A. Identification of a novel, dendritic cell-associated molecule, dectin-1, by subtractive cDNA cloning.. J Biol Chem 2000 Jun 30;275(26):20157-67.
- Brown GD, Taylor PR, Reid DM, Willment JA, Williams DL, Martinez-Pomares L, Wong SY, Gordon S. Dectin-1 is a major beta-glucan receptor on macrophages.. J Exp Med 2002 Aug 5;196(3):407-12.
- Heyl KA, Klassert TE, Heinrich A, Müller MM, Klaile E, Dienemann H, Grünewald C, Bals R, Singer BB, Slevogt H. Dectin-1 is expressed in human lung and mediates the proinflammatory immune response to nontypeable Haemophilus influenzae.. mBio 2014 Aug 26;5(5):e01492-14.
- Goodridge HS, Reyes CN, Becker CA, Katsumoto TR, Ma J, Wolf AJ, Bose N, Chan AS, Magee AS, Danielson ME, Weiss A, Vasilakos JP, Underhill DM. Activation of the innate immune receptor Dectin-1 upon formation of a 'phagocytic synapse'.. Nature 2011 Apr 28;472(7344):471-5.
- Hirose K, Ito T, Nakajima H. Roles of Dectin-1 in Allergic Airway Inflammation.. Crit Rev Immunol 2017;37(1):15-21.
- Hohl TM, Van Epps HL, Rivera A, Morgan LA, Chen PL, Feldmesser M, Pamer EG. Aspergillus fumigatus triggers inflammatory responses by stage-specific beta-glucan display.. PLoS Pathog 2005 Nov;1(3):e30.
- Brown J, O'Callaghan CA, Marshall AS, Gilbert RJ, Siebold C, Gordon S, Brown GD, Jones EY. Structure of the fungal beta-glucan-binding immune receptor dectin-1: implications for function.. Protein Sci 2007 Jun;16(6):1042-52.
- Heinsbroek SE, Taylor PR, Rosas M, Willment JA, Williams DL, Gordon S, Brown GD. Expression of functionally different dectin-1 isoforms by murine macrophages.. J Immunol 2006 May 1;176(9):5513-8.
- Willment JA, Gordon S, Brown GD. Characterization of the human beta -glucan receptor and its alternatively spliced isoforms.. J Biol Chem 2001 Nov 23;276(47):43818-23.
- Vesper S. Traditional mould analysis compared to a DNA-based method of mould analysis.. Crit Rev Microbiol 2011 Feb;37(1):15-24.
- Equine Respiratory Tissue Biobank. Laboratoire de Biologie Cellulaire et Moléculaire Respiratoire of the Université de Montréal. 2021. Accessed July 1, 2019. https://btre.ca/en/.
- Fillion-Bertrand G, Dickson RP, Boivin R, Lavoie JP, Huffnagle GB, Leclere M. Lung Microbiome Is Influenced by the Environment and Asthmatic Status in an Equine Model of Asthma.. Am J Respir Cell Mol Biol 2019 Feb;60(2):189-197.
- Leclere M, Lavoie-Lamoureux A, Gélinas-Lymburner E, David F, Martin JG, Lavoie JP. Effect of antigenic exposure on airway smooth muscle remodeling in an equine model of chronic asthma.. Am J Respir Cell Mol Biol 2011 Jul;45(1):181-7.
- . Database resources of the National Center for Biotechnology Information.. Nucleic Acids Res 2018 Jan 4;46(D1):D8-D13.
- Beekman L, Tohver T, Léguillette R. Comparison of cytokine mRNA expression in the bronchoalveolar lavage fluid of horses with inflammatory airway disease and bronchoalveolar lavage mastocytosis or neutrophilia using REST software analysis.. J Vet Intern Med 2012 Jan-Feb;26(1):153-61.
- Haugland RA, Vesper SJ. Method of Identifying and Quantifying Specific Fungi and Bacteria. Patent 6387652. U.S. Patent and Trademark Office, Washington, DC; 2002.
- Haugland RA, Varma M, Wymer LJ, Vesper SJ. Quantitative PCR analysis of selected Aspergillus, Penicillium and Paecilomyces species.. Syst Appl Microbiol 2004 Mar;27(2):198-210.
- Cox J, Indugula R, Vesper S, Zhu Z, Jandarov R, Reponen T. Comparison of indoor air sampling and dust collection methods for fungal exposure assessment using quantitative PCR.. Environ Sci Process Impacts 2017 Oct 18;19(10):1312-1319.
- Sun WK, Lu X, Li X, Sun QY, Su X, Song Y, Sun HM, Shi Y. Dectin-1 is inducible and plays a crucial role in Aspergillus-induced innate immune responses in human bronchial epithelial cells.. Eur J Clin Microbiol Infect Dis 2012 Oct;31(10):2755-64.
- Brown GD. Dectin-1: a signalling non-TLR pattern-recognition receptor.. Nat Rev Immunol 2006 Jan;6(1):33-43.
- Hadebe S, Brombacher F, Brown GD. C-Type Lectin Receptors in Asthma.. Front Immunol 2018;9:733.
- Liu ZC, Wang M, Sun WK, Xia D, Tan MM, Ding Y, Qian Q, Su X, Shi Y. Up-regulation of Dectin-1 in airway epithelial cells promotes mice defense against invasive pulmonary aspergillosis.. Int J Clin Exp Med 2015;8(10):17489-97.
- Peng XD, Zhao GQ, Lin J, Jiang N, Xu Q, Zhu CC, Qu JQ, Cong L, Li H. Fungus induces the release of IL-8 in human corneal epithelial cells, via Dectin-1-mediated protein kinase C pathways.. Int J Ophthalmol 2015;8(3):441-7.
- Ito T, Hirose K, Norimoto A, Saku A, Nakajima H. Dectin-1 plays a critical role in HDM-induced PGE(2) production in macrophages.. Allergol Int 2017 Sep;66S:S44-S46.
- Mintz-Cole RA, Gibson AM, Bass SA, Budelsky AL, Reponen T, Hershey GK. Dectin-1 and IL-17A suppress murine asthma induced by Aspergillus versicolor but not Cladosporium cladosporioides due to differences in β-glucan surface exposure.. J Immunol 2012 Oct 1;189(7):3609-17.
- LeibundGut-Landmann S, Gross O, Robinson MJ, Osorio F, Slack EC, Tsoni SV, Schweighoffer E, Tybulewicz V, Brown GD, Ruland J, Reis e Sousa C. Syk- and CARD9-dependent coupling of innate immunity to the induction of T helper cells that produce interleukin 17.. Nat Immunol 2007 Jun;8(6):630-8.
- Debrue M, Hamilton E, Joubert P, Lajoie-Kadoch S, Lavoie JP. Chronic exacerbation of equine heaves is associated with an increased expression of interleukin-17 mRNA in bronchoalveolar lavage cells.. Vet Immunol Immunopathol 2005 May 1;105(1-2):25-31.
- Berndt A, Derksen FJ, Venta PJ, Karmaus W, Ewart S, Yuzbasiyan-Gurkan V, Robinson NE. Expression of toll-like receptor 2 mRNA in bronchial epithelial cells is not induced in RAO-affected horses.. Equine Vet J 2009 Jan;41(1):76-81.
- Wilson ME, McCandless EE, Olszewski MA, Robinson NE. Alveolar macrophage phenotypes in severe equine asthma.. Vet J 2020 Feb;256:105436.
- Kato Y, Adachi Y, Ohno N. Contribution of N-linked oligosaccharides to the expression and functions of beta-glucan receptor, Dectin-1.. Biol Pharm Bull 2006 Aug;29(8):1580-6.
- Nardoni S, Mancianti F, Sgorbini M, Taccini F, Corazza M. Identification and seasonal distribution of airborne fungi in three horse stables in Italy.. Mycopathologia 2005 Aug;160(1):29-34.
- Samadi S, Wouters IM, Houben R, Jamshidifard AR, Van Eerdenburg F, Heederik DJ. Exposure to inhalable dust, endotoxins, beta(1->3)-glucans, and airborne microorganisms in horse stables.. Ann Occup Hyg 2009 Aug;53(6):595-603.
- Ivester KM, Couëtil LL, Moore GE. An observational study of environmental exposures, airway cytology, and performance in racing thoroughbreds.. J Vet Intern Med 2018 Sep;32(5):1754-1762.
- Schram-Bijkerk D, Doekes G, Douwes J, Boeve M, Riedler J, Ublagger E, von Mutius E, Benz MR, Pershagen G, van Hage M, Scheynius A, Braun-Fahrländer C, Waser M, Brunekreef B. Bacterial and fungal agents in house dust and wheeze in children: the PARSIFAL study.. Clin Exp Allergy 2005 Oct;35(10):1272-8.
- Ferro E, Ferrucci F, Salimei E, Antonin M, Codazza D, Caniatti M. Relationship between the conditions of lower airways in healthy horses, environmental factors and air quality in stables. Pferdeheilkunde 2000;16(6):579–586.
- Beeler-Marfisi J, Clark ME, Wen X, Sears W, Huber L, Ackerley C, Viel L, Bienzle D. Experimental induction of recurrent airway obstruction with inhaled fungal spores, lipopolysaccharide, and silica microspheres in horses.. Am J Vet Res 2010 Jun;71(6):682-9.
- Sattler S, Ghadially H, Hofer E. Evolution of the C-type lectin-like receptor genes of the DECTIN-1 cluster in the NK gene complex.. ScientificWorldJournal 2012;2012:931386.
Citations
This article has been cited 4 times.- Nascimento EFD, Batista PVC, Cunha CS, Lacerda LRA, Moura VC, Oliveira TQ, Filho AJMC, de Rezende PHF, Macedo DS, Vasconcelos SMM. Targeting the Dectin-1 Receptor in Neuroinflammation: Therapeutic Implications for Neuropsychiatric Disorders. ACS Chem Neurosci 2025 Aug 20;16(16):3082-3095.
- Dély S, Gerber V, Peters LM, Sage SE. Association between equine asthma and fungal elements in the tracheal wash: An environment-matched case-control study. PLoS One 2024;19(9):e0309835.
- Mohammad Taheri M, Javan F, Poudineh M, Athari SS. Beyond CAR-T: The rise of CAR-NK cell therapy in asthma immunotherapy. J Transl Med 2024 Aug 5;22(1):736.
- Diez de Castro E, Fernandez-Molina JM. Environmental Management of Equine Asthma. Animals (Basel) 2024 Jan 30;14(3).
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