Abstract
The immunology of the hygiene hypothesis of allergy is complex and involves the loss of cellular and humoral immunoregulatory pathways as a result of the adoption of a Western lifestyle and the disappearance of chronic infectious diseases. The influence of diet and reduced microbiome diversity now forms the foundation of scientific thinking on how the allergy epidemic occurred, although clear mechanistic insights into the process in humans are still lacking. Here we propose that barrier epithelial cells are heavily influenced by environmental factors and by microbiome-derived danger signals and metabolites, and thus act as important rheostats for immunoregulation, particularly during early postnatal development. Preventive strategies based on this new knowledge could exploit the diversity of the microbial world and the way humans react to it, and possibly restore old symbiotic relationships that have been lost in recent times, without causing disease or requiring a return to an unhygienic life style.
This is a preview of subscription content, access via your institution
Relevant articles
Open Access articles citing this article.
-
What inhalant allergens can do and not do?—The cooperation of allergens and their source in Th2 polarization and allergic sensitization
Allergo Journal International Open Access 28 July 2023
-
Gene–environment interactions and their impact on human health
Genes & Immunity Open Access 30 December 2022
-
Oral administration of Faecalibacterium prausnitzii and Akkermansia muciniphila strains from humans improves atopic dermatitis symptoms in DNCB induced NC/Nga mice
Scientific Reports Open Access 05 May 2022
Access options
Access Nature and 54 other Nature Portfolio journals
Get Nature+, our best-value online-access subscription
$29.99 / 30 days
cancel any time
Subscribe to this journal
Receive 12 print issues and online access
$209.00 per year
only $17.42 per issue
Rent or buy this article
Prices vary by article type
from$1.95
to$39.95
Prices may be subject to local taxes which are calculated during checkout


References
Umetsu, D.T., McIntire, J.J., Akbari, O., Macaubas, C. & DeKruyff, R.H. Asthma: an epidemic of dysregulated immunity. Nat. Immunol. 3, 715–720 (2002).
Eder, W., Ege, M.J. & von Mutius, E. The asthma epidemic. N. Engl. J. Med. 355, 2226–2235 (2006).
Bach, J.F. The effect of infections on susceptibility to autoimmune and allergic diseases. N. Engl. J. Med. 347, 911–920 (2002).
Platts-Mills, T.A. The allergy epidemics: 1870-2010. J. Allergy Clin. Immunol. 136, 3–13 (2015).
Sicherer, S.H., Muñoz-Furlong, A., Godbold, J.H. & Sampson, H.A. US prevalence of self-reported peanut, tree nut, and sesame allergy: 11-year follow-up. J. Allergy Clin. Immunol. 125, 1322–1326 (2010).
Gerrard, J.W., Geddes, C.A., Reggin, P.L., Gerrard, C.D. & Horne, S. Serum IgE levels in white and Metis communities in Saskatchewan. Ann. Allergy 37, 91–100 (1976).
Strachan, D.P. Hay fever, hygiene, and household size. Br. Med. J. 299, 1259–1260 (1989).
Strachan, D.P. et al. Siblings, asthma, rhinoconjunctivitis and eczema: a worldwide perspective from the International Study of Asthma and Allergies in Childhood. Clin. Exp. Allergy 45, 126–136 (2015).
Illi, S. et al. Early childhood infectious diseases and the development of asthma up to school age: a birth cohort study. Br. Med. J. 322, 390–395 (2001).
Smits, H.H. et al. Microbes and asthma: opportunities for intervention. J. Allergy Clin. Immunol. 137, 690–697 (2016).
Feldman, A.S., He, Y., Moore, M.L., Hershenson, M.B. & Hartert, T.V. Toward primary prevention of asthma. Reviewing the evidence for early-life respiratory viral infections as modifiable risk factors to prevent childhood asthma. Am. J. Respir. Crit. Care Med. 191, 34–44 (2015).
Rantala, A.K., Jaakkola, M.S., Mäkikyrö, E.M., Hugg, T.T. & Jaakkola, J.J. Early respiratory infections and the development of asthma in the first 27 years of life. Am. J. Epidemiol. 182, 615–623 (2015).
Matricardi, P.M., Rosmini, F., Panetta, V., Ferrigno, L. & Bonini, S. Hay fever and asthma in relation to markers of infection in the United States. J. Allergy Clin. Immunol. 110, 381–387 (2002).
McIntire, J.J. et al. Identification of Tapr (an airway hyperreactivity regulatory locus) and the linked Tim gene family. Nat. Immunol. 2, 1109–1116 (2001).
Janse, J.J. et al. The association between foodborne and orofecal pathogens and allergic sensitization—EuroPrevall study. Pediatr. Allergy Immunol. 25, 250–256 (2014).
von Mutius, E. et al. Prevalence of asthma and atopy in two areas of West and East Germany. Am. J. Respir. Crit. Care Med. 149, 358–364 (1994).
Strachan, D. et al. Worldwide variations in prevalence of symptoms of allergic rhinoconjunctivitis in children: the International Study of Asthma and Allergies in Childhood (ISAAC). Pediatr. Allergy Immunol. 8, 161–176 (1997).
Alberca-Custódio, R.W. et al. Aerobic exercise reduces asthma phenotype by modulation of the leukotriene pathway. Front. Immunol. 7, 237 (2016).
Rook, G.A. Hygiene hypothesis and autoimmune diseases. Clin. Rev. Allergy Immunol. 42, 5–15 (2012).
Hanski, I. et al. Environmental biodiversity, human microbiota, and allergy are interrelated. Proc. Natl. Acad. Sci. USA 109, 8334–8339 (2012).
Arrieta, M.C. et al. Early infancy microbial and metabolic alterations affect risk of childhood asthma. Sci. Transl. Med. 7, 307ra152 (2015).
Depner, M. et al. Bacterial microbiota of the upper respiratory tract and childhood asthma. J. Allergy Clin. Immunol. 139, 826–834.e13 (2017).
Hua, X., Goedert, J.J., Pu, A., Yu, G. & Shi, J. Allergy associations with the adult fecal microbiota: analysis of the American Gut Project. EBioMedicine 3, 172–179 (2015).
Lodge, C.J. et al. Breastfeeding and asthma and allergies: a systematic review and meta-analysis. Acta Paediatr. 104, 38–53 (2015).
Loss, G. et al. Consumption of unprocessed cow's milk protects infants from common respiratory infections. J. Allergy Clin. Immunol. 135, 56–62 (2015).
Martin, R. et al. Early-life events, including mode of delivery and type of feeding, siblings and gender, shape the developing gut microbiota. PLoS One 11, e0158498 (2016).
Hasegawa, K. et al. Household siblings and nasal and fecal microbiota in infants. Pediatr. Int. 59, 473–481 (2017).
Tun, H.M. et al. Exposure to household furry pets influences the gut microbiota of infant at 3-4 months following various birth scenarios. Microbiome 5, 40 (2017).
Lambrecht, B.N. & Hammad, H. The immunology of asthma. Nat. Immunol. 16, 45–56 (2015).
Pulendran, B. & Artis, D. New paradigms in type 2 immunity. Science 337, 431–435 (2012).
Coquet, J.M. et al. Interleukin-21-producing CD4+ T cells promote type 2 immunity to house dust mites. Immunity 43, 318–330 (2015).
Hansen, G., Yeung, V.P., Berry, G., Umetsu, D.T. & DeKruyff, R.H. Vaccination with heat-killed Listeria as adjuvant reverses established allergen-induced airway hyperreactivity and inflammation: role of CD8+ T cells and IL-18. J. Immunol. 164, 223–230 (2000).
Eisenbarth, S.C. et al. Lipopolysaccharide-enhanced, Toll-like receptor 4-dependent T helper cell type 2 responses to inhaled antigen. J. Exp. Med. 196, 1645–1651 (2002).
Bacher, P. et al. Regulatory T cell specificity directs tolerance versus allergy against aeroantigens in humans. Cell 167, 1067–1078.e16 (2016).
Stephens, R., Randolph, D.A., Huang, G., Holtzman, M.J. & Chaplin, D.D. Antigen-nonspecific recruitment of Th2 cells to the lung as a mechanism for viral infection-induced allergic asthma. J. Immunol. 169, 5458–5467 (2002).
van den Biggelaar, A.H. et al. Decreased atopy in children infected with Schistosoma haematobium: a role for parasite-induced interleukin-10. Lancet 356, 1723–1727 (2000).
Schmiedel, Y. et al. CD4+CD25hiFOXP3+ regulatory T cells and cytokine responses in human schistosomiasis before and after treatment with praziquantel. PLoS Negl. Trop. Dis. 9, e0003995 (2015).
Wilson, M.S. et al. Suppression of allergic airway inflammation by helminth-induced regulatory T cells. J. Exp. Med. 202, 1199–1212 (2005).
Smits, H.H. et al. Protective effect of Schistosoma mansoni infection on allergic airway inflammation depends on the intensity and chronicity of infection. J. Allergy Clin. Immunol. 120, 932–940 (2007).
van der Vlugt, L.E.P.M. et al. Schistosome-induced pulmonary B cells inhibit allergic airway inflammation and display a reduced Th2-driving function. Int. J. Parasitol. 47, 545–554 (2017).
Holt, P.G. et al. Distinguishing benign from pathologic TH2 immunity in atopic children. J. Allergy Clin. Immunol. 137, 379–387 (2016).
Arnold, I.C. et al. Helicobacter pylori infection prevents allergic asthma in mouse models through the induction of regulatory T cells. J. Clin. Invest. 121, 3088–3093 (2011).
Geuking, M.B. et al. Intestinal bacterial colonization induces mutualistic regulatory T cell responses. Immunity 34, 794–806 (2011).
Ohnmacht, C. et al. The microbiota regulates type 2 immunity through RORγt+ T cells. Science 349, 989–993 (2015).
Furusawa, Y. et al. Commensal microbe-derived butyrate induces the differentiation of colonic regulatory T cells. Nature 504, 446–450 (2013).
Arpaia, N. et al. Metabolites produced by commensal bacteria promote peripheral regulatory T-cell generation. Nature 504, 451–455 (2013).
Navarro, S. et al. The oral administration of bacterial extracts prevents asthma via the recruitment of regulatory T cells to the airways. Mucosal Immunol. 4, 53–65 (2011).
Lluis, A. et al. Increased regulatory T-cell numbers are associated with farm milk exposure and lower atopic sensitization and asthma in childhood. J. Allergy Clin. Immunol. 133, 551–559 (2014).
Schaub, B. et al. Maternal farm exposure modulates neonatal immune mechanisms through regulatory T cells. J. Allergy Clin. Immunol. 123, 774–782 (2009).
Schröder, P.C. et al. A switch in regulatory T cells through farm exposure during immune maturation in childhood. Allergy 72, 604–615 (2017).
Akdis, C.A. et al. Induction and differential regulation of bee venom phospholipase A2-specific human IgE and IgG4 antibodies in vitro requires allergen-specific and nonspecific activation of T and B cells. J. Allergy Clin. Immunol. 99, 345–353 (1997).
Mitre, E., Norwood, S. & Nutman, T.B. Saturation of immunoglobulin E (IgE) binding sites by polyclonal IgE does not explain the protective effect of helminth infections against atopy. Infect. Immun. 73, 4106–4111 (2005).
van de Veen, W. et al. IgG4 production is confined to human IL-10-producing regulatory B cells that suppress antigen-specific immune responses. J. Allergy Clin. Immunol. 131, 1204–1212 (2013).
Strait, R.T., Morris, S.C. & Finkelman, F.D. IgG-blocking antibodies inhibit IgE-mediated anaphylaxis in vivo through both antigen interception and Fc gamma RIIb cross-linking. J. Clin. Invest. 116, 833–841 (2006).
Tyagi, N. et al. Comparisons of allergenic and metazoan parasite proteins: allergy the price of immunity. PLOS Comput. Biol. 11, e1004546 (2015).
Amoah, A.S. et al. Peanut-specific IgE antibodies in asymptomatic Ghanaian children possibly caused by carbohydrate determinant cross-reactivity. J. Allergy Clin. Immunol. 132, 639–647 (2013).
Valmonte, G.R., Cauyan, G.A. & Ramos, J.D. IgE cross-reactivity between house dust mite allergens and Ascaris lumbricoides antigens. Asia Pac. Allergy 2, 35–44 (2012).
Patel, P.S., King, R.G. & Kearney, J.F. Pulmonary α-1,3-glucan-specific IgA-secreting B cells suppress the development of cockroach allergy. J. Immunol. 197, 3175–3187 (2016).
Patel, P.S. & Kearney, J.F. Neonatal exposure to pneumococcal phosphorylcholine modulates the development of house dust mite allergy during adult life. J. Immunol. 194, 5838–5850 (2015).
Kin, N.W., Stefanov, E.K., Dizon, B.L. & Kearney, J.F. Antibodies generated against conserved antigens expressed by bacteria and allergen-bearing fungi suppress airway disease. J. Immunol. 189, 2246–2256 (2012).
Kearney, J.F., Patel, P., Stefanov, E.K. & King, R.G. Natural antibody repertoires: development and functional role in inhibiting allergic airway disease. Annu. Rev. Immunol. 33, 475–504 (2015).
Merad, M., Sathe, P., Helft, J., Miller, J. & Mortha, A. The dendritic cell lineage: ontogeny and function of dendritic cells and their subsets in the steady state and the inflamed setting. Annu. Rev. Immunol. 31, 563–604 (2013).
Deckers, J. et al. Epicutaneous sensitization to house dust mite allergen requires interferon regulatory factor 4-dependent dermal dendritic cells. J. Allergy Clin. Immunol. (2017).
Halim, T.Y. et al. Group 2 innate lymphoid cells are critical for the initiation of adaptive T helper 2 cell-mediated allergic lung inflammation. Immunity 40, 425–435 (2014).
Trompette, A. et al. Gut microbiota metabolism of dietary fiber influences allergic airway disease and hematopoiesis. Nat. Med. 20, 159–166 (2014).
de Heer, H.J. et al. Essential role of lung plasmacytoid dendritic cells in preventing asthmatic reactions to harmless inhaled antigen. J. Exp. Med. 200, 89–98 (2004).
McGuirk, P., McCann, C. & Mills, K.H. Pathogen-specific T regulatory 1 cells induced in the respiratory tract by a bacterial molecule that stimulates interleukin 10 production by dendritic cells: a novel strategy for evasion of protective T helper type 1 responses by Bordetella pertussis. J. Exp. Med. 195, 221–231 (2002).
Smits, H.H. et al. Cholera toxin B suppresses allergic inflammation through induction of secretory IgA. Mucosal Immunol. 2, 331–339 (2009).
Hammad, H. & Lambrecht, B.N. Barrier epithelial cells and the control of type 2 immunity. Immunity 43, 29–40 (2015).
Hammad, H. et al. House dust mite allergen induces asthma via Toll-like receptor 4 triggering of airway structural cells. Nat. Med. 15, 410–416 (2009).
Guo, L. et al. Innate immunological function of TH2 cells in vivo. Nat. Immunol. 16, 1051–1059 (2015).
Van Dyken, S.J. et al. A tissue checkpoint regulates type 2 immunity. Nat. Immunol. 17, 1381–1387 (2016).
Lloyd, C.M. & Marsland, B.J. Lung homeostasis: influence of age, microbes, and the immune system. Immunity 46, 549–561 (2017).
de Kleer, I.M. et al. Perinatal activation of the interleukin-33 pathway promotes type 2 immunity in the developing lung. Immunity 45, 1285–1298 (2016).
Steer, C.A. et al. Group 2 innate lymphoid cell activation in the neonatal lung drives type 2 immunity and allergen sensitization. J. Allergy Clin. Immunol. 140, 593–595 (2017).
Saluzzo, S. et al. First-breath-induced type 2 pathways shape the lung immune environment. Cell Rep. 18, 1893–1905 (2017).
Gollwitzer, E.S. et al. Lung microbiota promotes tolerance to allergens in neonates via PD-L1. Nat. Med. 20, 642–647 (2014).
Braun-Fahrländer, C. et al. Environmental exposure to endotoxin and its relation to asthma in school-age children. N. Engl. J. Med. 347, 869–877 (2002).
Loss, G.J. et al. The early development of wheeze. Environmental determinants and genetic susceptibility at 17q21. Am. J. Respir. Crit. Care Med. 193, 889–897 (2016).
House, J.S. et al. Early-life farm exposures and adult asthma and atopy in the Agricultural Lung Health Study. J. Allergy Clin. Immunol. 140, 249–256 (2017).
Stein, M.M. et al. Innate immunity and asthma risk in Amish and Hutterite farm children. N. Engl. J. Med. 375, 411–421 (2016).
Schuijs, M.J. et al. Farm dust and endotoxin protect against allergy through A20 induction in lung epithelial cells. Science 349, 1106–1110 (2015).
Wang, J., Ouyang, Y., Guner, Y., Ford, H.R. & Grishin, A.V. Ubiquitin-editing enzyme A20 promotes tolerance to lipopolysaccharide in enterocytes. J. Immunol. 183, 1384–1392 (2009).
Brand, S. et al. Epigenetic regulation in murine offspring as a novel mechanism for transmaternal asthma protection induced by microbes. J. Allergy Clin. Immunol. 128, 618–625 (2011).
Conrad, M.L. et al. Maternal TLR signaling is required for prenatal asthma protection by the nonpathogenic microbe Acinetobacter lwoffii F78. J. Exp. Med. 206, 2869–2877 (2009).
McFarlane, A.J. et al. Enteric helminth-induced type I interferon signaling protects against pulmonary virus infection through interaction with the microbiota. J. Allergy Clin. Immunol. (in the press).
McSorley, H.J., Blair, N.F., Smith, K.A., McKenzie, A.N. & Maizels, R.M. Blockade of IL-33 release and suppression of type 2 innate lymphoid cell responses by helminth secreted products in airway allergy. Mucosal Immunol. 7, 1068–1078 (2014).
Melendez, A.J. et al. Inhibition of FcɛRI-mediated mast cell responses by ES-62, a product of parasitic filarial nematodes. Nat. Med. 13, 1375–1381 (2007).
Rzepecka, J. et al. The helminth product, ES-62, protects against airway inflammation by resetting the Th cell phenotype. Int. J. Parasitol. 43, 211–223 (2013).
Schnoeller, C. et al. A helminth immunomodulator reduces allergic and inflammatory responses by induction of IL-10-producing macrophages. J. Immunol. 180, 4265–4272 (2008).
Daniłowicz-Luebert, E. et al. A nematode immunomodulator suppresses grass pollen-specific allergic responses by controlling excessive Th2 inflammation. Int. J. Parasitol. 43, 201–210 (2013).
McSorley, H.J. et al. Suppression of type 2 immunity and allergic airway inflammation by secreted products of the helminth Heligmosomoides polygyrus. Eur. J. Immunol. 42, 2667–2682 (2012).
Ebner, F. et al. Therapeutic potential of larval excretory/secretory proteins of the pig whipworm Trichuris suis in allergic disease. Allergy 69, 1489–1497 (2014).
Park, S.K. et al. Macrophage migration inhibitory factor homologs of anisakis simplex suppress Th2 response in allergic airway inflammation model via CD4+CD25+Foxp3+ T cell recruitment. J. Immunol. 182, 6907–6914 (2009).
Park, H.K. et al. Macrophage migration inhibitory factor isolated from a parasite inhibited Th2 cytokine production in PBMCs of atopic asthma patients. J. Asthma 49, 10–15 (2012).
Navarro, S. et al. Hookworm recombinant protein promotes regulatory T cell responses that suppress experimental asthma. Sci. Transl. Med. 8, 362ra143 (2016).
Acknowledgements
B.N.L. and H.H. are supported by Ghent University (Concerted Research Initiative (GOA) grant) and by the Scientific Research Foundation Flanders (FWO).
Author information
Authors and Affiliations
Corresponding authors
Ethics declarations
Competing interests
The authors declare no competing financial interests.
Rights and permissions
About this article
Cite this article
Lambrecht, B., Hammad, H. The immunology of the allergy epidemic and the hygiene hypothesis. Nat Immunol 18, 1076–1083 (2017). https://doi.org/10.1038/ni.3829
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/ni.3829
This article is cited by
-
Clarifying the effect of gut microbiota on allergic conjunctivitis risk is instrumental for predictive, preventive, and personalized medicine: a Mendelian randomization analysis
EPMA Journal (2023)
-
The gut microbiome and allergic rhinitis; refocusing on the role of probiotics as a treatment option
European Archives of Oto-Rhino-Laryngology (2023)
-
What inhalant allergens can do and not do?—The cooperation of allergens and their source in Th2 polarization and allergic sensitization
Allergo Journal International (2023)
-
ENKD1 promotes epidermal stratification by regulating spindle orientation in basal keratinocytes
Cell Death & Differentiation (2022)
-
Oral administration of Faecalibacterium prausnitzii and Akkermansia muciniphila strains from humans improves atopic dermatitis symptoms in DNCB induced NC/Nga mice
Scientific Reports (2022)