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Zhang X, Hu X, Tian T, Pang W. The role of ICOS in allergic disease: Positive or Negative? Int Immunopharmacol 2021; 103:108394. [PMID: 34922247 DOI: 10.1016/j.intimp.2021.108394] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 11/15/2021] [Accepted: 11/19/2021] [Indexed: 01/09/2023]
Abstract
With the rapid increase in the incidence of allergic diseases, the mechanisms underlying the development of these diseases have received a great deal of attention, and this is particularly true in regard to the role of ICOS in allergic diseases. Current studies have revealed that ICOS affects the functional activity of multiple immune cells that modulate the adaptive immune system. Additionally, ICOS also plays a crucial role in mediating cellular immunity and coordinating the response of the entire immune system, and thus, it plays a role in allergic reactions. However, the ICOS/ICOS-ligand (ICOS-L) axis functions in a dual role during the development of multiple allergic diseases. In this review, we explore the role of ICOS/ICOSL in the context of different immune cells that function in allergic diseases, and we summarize recent advances in their contribution to these diseases.
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Affiliation(s)
- Xueyan Zhang
- Department of Otorhinolaryngology-Head and Neck Surgery, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Xianyang Hu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Department of Medical Microbiology and Parasitology, School of Basic Medical Sciences, Shanghai Medical College of Fudan University, Shanghai, China
| | - Tengfei Tian
- Department of Otolaryngology-Head and Neck Surgery, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai, China
| | - Wenhui Pang
- Department of Otorhinolaryngology-Head and Neck Surgery, The Affiliated Hospital of Qingdao University, Qingdao, China.
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Howard E, Lewis G, Galle-Treger L, Hurrell BP, Helou DG, Shafiei-Jahani P, Painter JD, Muench GA, Soroosh P, Akbari O. IL-10 production by ILC2s requires Blimp-1 and cMaf, modulates cellular metabolism, and ameliorates airway hyperreactivity. J Allergy Clin Immunol 2021; 147:1281-1295.e5. [PMID: 32905799 DOI: 10.1016/j.jaci.2020.08.024] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 07/21/2020] [Accepted: 08/21/2020] [Indexed: 01/27/2023]
Abstract
BACKGROUND Group 2 innate lymphoid cells (ILC2s) are the dominant innate lymphoid cell population in the lungs at steady state, and their release of type 2 cytokines is a central driver in responding eosinophil infiltration and increased airway hyperreactivity. Our laboratory has identified a unique subset of ILC2s in the lungs that actively produce IL-10 (ILC210s). OBJECTIVE Our aim was to characterize the effector functions of ILC210s in the development and pathology of allergic asthma. METHODS IL-4-stimulated ILC210s were isolated to evaluate cytokine secretion, transcription factor signaling, metabolic dependence, and effector functions in vitro. ILC210s were also adoptively transferred into Rag2-/-γc-/- mice, which were then challenged with IL-33 and assessed for airway hyperreactivity and lung inflammation. RESULTS We have determined that the transcription factors cMaf and Blimp-1 regulate IL-10 expression in ILC210s. Strikingly, our results demonstrate that ILC210s can utilize both autocrine and paracrine signaling to suppress proinflammatory ILC2 effector functions in vitro. Further, this subset dampens airway hyperreactivity and significantly reduces lung inflammation in vivo. Interestingly, ILC210s demonstrated a metabolic dependency on the glycolytic pathway for IL-10 production, shifting from the fatty acid oxidation pathway conventionally utilized for proinflammatory effector functions. CONCLUSION These findings provide an important and previously unrecognized role of ILC210s in diseases associated with ILC2s such as allergic lung inflammation and asthma. They also provide new insights into the metabolism dependency of proinflammatory and anti-inflammatory ILC2 phenotypes.
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Affiliation(s)
- Emily Howard
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, Calif
| | - Gavin Lewis
- Janssen Research and Development, San Diego, Calif
| | - Lauriane Galle-Treger
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, Calif
| | - Benjamin P Hurrell
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, Calif
| | - Doumet Georges Helou
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, Calif
| | - Pedram Shafiei-Jahani
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, Calif
| | - Jacob D Painter
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, Calif
| | | | | | - Omid Akbari
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, Calif.
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Hurrell BP, Howard E, Galle-Treger L, Helou DG, Shafiei-Jahani P, Painter JD, Akbari O. Distinct Roles of LFA-1 and ICAM-1 on ILC2s Control Lung Infiltration, Effector Functions, and Development of Airway Hyperreactivity. Front Immunol 2020; 11:542818. [PMID: 33193309 PMCID: PMC7662114 DOI: 10.3389/fimmu.2020.542818] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Accepted: 10/08/2020] [Indexed: 12/19/2022] Open
Abstract
Asthma is a heterogeneous airway inflammatory disease characterized by increased airway hyperreactivity (AHR) to specific and unspecific stimuli. Group 2 innate lymphoid cells (ILC2)s are type-2 cytokine secreting cells capable of inducing eosinophilic lung inflammation and AHR independent of adaptive immunity. Remarkably, reports show that ILC2s are increased in the blood of human asthmatics as compared to healthy donors. Nevertheless, whether ILC2 expression of adhesion molecules regulates ILC2 trafficking remains unknown. Our results show that IL-33-activated ILC2s not only express LFA-1 but also strikingly LFA-1 ligand ICAM-1. Both LFA-1-/- and ICAM-1-/- mice developed attenuated AHR in response to IL-33 intranasal challenge, associated with a lower airway inflammation and less lung ILC2 accumulation compared to controls. Our mixed bone marrow chimera studies however revealed that ILC2 expression of LFA-1 - but not ICAM-1 - was required for their accumulation in the inflamed lungs. Importantly, we found that LFA-1 remarkably controlled ILC2 homing to the lungs, suggesting that LFA-1 is involved in ILC2 trafficking to the lungs. Our exploratory transcriptomic analysis further revealed that ICAM-1 deficiency on ILC2s significantly affects their effector functions. While it downregulated pro-inflammatory cytokines such as Il5, Il9, Il13, and Csf2, it however notably also upregulated cytokines including Il10 both at the transcriptomic and protein levels. These findings provide novel avenues for future investigations, as modulation of LFA-1 and/or ICAM-1 represents an unappreciated regulatory mechanism for ILC2 trafficking and cytokine production respectively, potentially serving as therapeutic target for ILC2-dependent diseases such as allergic asthma.
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Affiliation(s)
- Benjamin P Hurrell
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Emily Howard
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Lauriane Galle-Treger
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Doumet Georges Helou
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Pedram Shafiei-Jahani
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Jacob D Painter
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Omid Akbari
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
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Painter JD, Galle-Treger L, Akbari O. Role of Autophagy in Lung Inflammation. Front Immunol 2020; 11:1337. [PMID: 32733448 PMCID: PMC7358431 DOI: 10.3389/fimmu.2020.01337] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 05/26/2020] [Indexed: 12/11/2022] Open
Abstract
Autophagy is a cellular recycling system found in almost all types of eukaryotic organisms. The system is made up of a variety of proteins which function to deliver intracellular cargo to lysosomes for formation of autophagosomes in which the contents are degraded. The maintenance of cellular homeostasis is key in the survival and function of a variety of human cell populations. The interconnection between metabolism and autophagy is extensive, therefore it has a role in a variety of different cell functions. The disruption or dysfunction of autophagy in these cell types have been implicated in the development of a variety of inflammatory diseases including asthma. The role of autophagy in non-immune and immune cells both lead to the pathogenesis of lung inflammation. Autophagy in pulmonary non-immune cells leads to tissue remodeling which can develop into chronic asthma cases with long term effects. The role autophagy in the lymphoid and myeloid lineages in the pathology of asthma differ in their functions. Impaired autophagy in lymphoid populations have been shown, in general, to decrease inflammation in both asthma and inflammatory disease models. Many lymphoid cells rely on autophagy for effector function and maintained inflammation. In stark contrast, autophagy deficient antigen presenting cells have been shown to have an activated inflammasome. This is largely characterized by a TH17 response that is accompanied with a much worse prognosis including granulocyte mediated inflammation and steroid resistance. The cell specificity associated with changes in autophagic flux complicates its targeting for amelioration of asthmatic symptoms. Differing asthmatic phenotypes between TH2 and TH17 mediated disease may require different autophagic modulations. Therefore, treatments call for a more cell specific and personalized approach when looking at chronic asthma cases. Viral-induced lung inflammation, such as that caused by SARS-CoV-2, also may involve autophagic modulation leading to inflammation mediated by lung resident cells. In this review, we will be discussing the role of autophagy in non-immune cells, myeloid cells, and lymphoid cells for their implications into lung inflammation and asthma. Finally, we will discuss autophagy's role viral pathogenesis, immunometabolism, and asthma with insights into autophagic modulators for amelioration of lung inflammation.
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Affiliation(s)
- Jacob D Painter
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Lauriane Galle-Treger
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Omid Akbari
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
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Czarnowicki T, He H, Canter T, Han J, Lefferdink R, Erickson T, Rangel S, Kameyama N, Kim HJ, Pavel AB, Estrada Y, Krueger JG, Paller AS, Guttman-Yassky E. Evolution of pathologic T-cell subsets in patients with atopic dermatitis from infancy to adulthood. J Allergy Clin Immunol 2019; 145:215-228. [PMID: 31626841 DOI: 10.1016/j.jaci.2019.09.031] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2019] [Revised: 08/23/2019] [Accepted: 09/12/2019] [Indexed: 12/20/2022]
Abstract
BACKGROUND The circulating immune phenotype was defined in adults and young children with early atopic dermatitis (AD), but chronologic changes in the blood of infants and children with AD through adolescence have not been explored. OBJECTIVE We sought to compare immune activation and cytokine polarization in the blood of 0- to 5-year-old (n = 39), 6- to 11-year-old (n = 26), 12- to 17-year-old (n = 21) and 18-year-old or older (n = 43) patients with AD versus age-matched control subjects. METHODS Flow cytometry was used to measure IFN-γ, IL-9, IL-13, IL-17, and IL-22 cytokine levels in CD4+/CD8+ T cells, with inducible costimulator molecule and HLA-DR defining midterm and long-term T-cell activation, respectively, within skin-homing/cutaneous lymphocyte antigen (CLA)+ versus systemic/CLA- T cells. Unsupervised clustering differentiated patients based on their blood biomarker frequencies. RESULTS Although CLA+ TH1 frequencies were significantly lower in infants with AD versus all older patients (P < .01), frequencies of CLA+ TH2 T cells were similarly expanded across all AD age groups compared with control subjects (P < .05). After infancy, CLA- TH2 frequencies were increased in patients with AD in all age groups, suggesting systemic immune activation with disease chronicity. IL-22 frequencies serially increased from normal levels in infants to highly significant levels in adolescents and adults compared with levels in respective control subjects (P < .01). Unsupervised clustering aligned the AD profiles along an age-related spectrum from infancy to adulthood (eg, inducible costimulator molecule and IL-22). CONCLUSIONS The adult AD phenotype is achieved only in adulthood. Unique cytokine signatures characterizing individual pediatric endotypes might require age-specific therapies. Future longitudinal studies, comparing the profile of patients with cleared versus persistent pediatric AD, might define age-specific changes that predict AD clearance.
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Affiliation(s)
- Tali Czarnowicki
- Department of Dermatology and the Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY; Laboratory for Investigative Dermatology, Rockefeller University, New York, NY
| | - Helen He
- Department of Dermatology and the Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Talia Canter
- Departments of Dermatology and Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Joseph Han
- Department of Dermatology and the Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Rachel Lefferdink
- Departments of Dermatology and Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Taylor Erickson
- Departments of Dermatology and Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Stephanie Rangel
- Departments of Dermatology and Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Naoya Kameyama
- Department of Dermatology and the Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Hyun Je Kim
- Department of Dermatology and the Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Ana B Pavel
- Department of Dermatology and the Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Yeriel Estrada
- Department of Dermatology and the Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - James G Krueger
- Laboratory for Investigative Dermatology, Rockefeller University, New York, NY
| | - Amy S Paller
- Departments of Dermatology and Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Emma Guttman-Yassky
- Department of Dermatology and the Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY.
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Huang W, Song Y, Wang L. Wenshen decoction suppresses inflammation in IL-33-induced asthma murine model via inhibiting ILC2 activation. ANNALS OF TRANSLATIONAL MEDICINE 2019; 7:570. [PMID: 31807551 DOI: 10.21037/atm.2019.09.34] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Background Wenshen decoction, consisting of Epimedium brevicornu Maxim, Morinda officinalis How and Cnidium monnieri (L.) Cusson, has favorable efficacy in the treatment of asthma in China. Methods The present study investigated the potential immunomodulatory mechanism underlying the therapeutic effects of Wenshen decoction on mouse asthma. Results Oral Wenshen decoction could ameliorate the production of IL-4, IL-5, IL-13 in the bronchoalveolar lavage fluid (BALF), reduce serum IgE, and improve the airway hyperresponsiveness (AHR) and airway inflammation in the BALB/c mice after intranasal treatment with recombinant IL-33. Moreover, Wenshen decoction reduced ILC2 and RORα mRNA expression, decreased the mRNA expression of ICOS and ST2 in the lung, but significantly increased the production of IFN-γ. Conclusions Our study indicates that Wenshen decoction may inhibit the activation of ILC2 through the IL-33/ST2/ICOS pathway to further suppress airway inflammation and AHR in the asthmatic mice, and the increased IFN-γ might be related to the effects of Wenshen decoction on ILC2.
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Affiliation(s)
- Weiling Huang
- Department of Respiration, Shanghai Municipal Hospital of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 200071, China
| | - Ying Song
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Lixin Wang
- Department of Integrated TCM and Western Medicine, Shanghai Pulmonary Hospital, Tongji University, Shanghai 200433, China
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Montes-Casado M, Ojeda G, Aragoneses-Fenoll L, López D, de Andrés B, Gaspar ML, Dianzani U, Rojo JM, Portolés P. ICOS deficiency hampers the homeostasis, development and function of NK cells. PLoS One 2019; 14:e0219449. [PMID: 31283790 PMCID: PMC6613708 DOI: 10.1371/journal.pone.0219449] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 06/24/2019] [Indexed: 01/02/2023] Open
Abstract
Signaling through the inducible costimulator ICOS is required for the homeostasis and function of various immune cell populations, with an outstanding role in the generation and maintenance of germinal centers. Very recently, it has been suggested that the clinical phenotype of ICOS-deficient patients is much broader than initially anticipated and the innate immune response might be also affected. However, the role of the ICOS/ICOS-Ligand axis in the homeostasis and development of innate NK cells is not known, and reports on its participation in NK cell activation are scarce. NK cells may express low levels of ICOS that are markedly enhanced upon activation. We show here that ICOS-deficient (ICOS-KO) mice present low NK cell numbers and defects in the homeostasis of these cells, with delayed maturation and altered expression of the developmental NK cell markers CD122, NK1.1, CD11b or CD27. Our experiments in mixed bone marrow chimera mice indicate that, both, cell-intrinsic defects of ICOS-KO NK and deficiencies in the milieu of these mice contribute to the altered phenotype. ICOS-deficient NK cells show impaired production of IFN-γ and cytotoxicity, and a final outcome of defects in NK cell-mediated effector function during the response to poly(I:C) or vaccinia virus infection in vivo. Interestingly, we show that murine innate cells like IL-2-cultured NK and bone marrow-derived dendritic cells can simultaneously express ICOS and ICOS-Ligand; both molecules are functional in NK intracellular signaling, enhancing early phosphorylation of Akt and Erk, or IFN-γ secretion in IL-2-activated NK cells. Our study shows the functional importance of the ICOS/ICOS-L pair in NK cell homeostasis, differentiation and activity and suggests novel therapeutic targets for NK manipulation.
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Affiliation(s)
- María Montes-Casado
- Centro Nacional de Microbiología, Instituto de Salud Carlos III (ISCIII), Majadahonda, Madrid, Spain
| | - Gloria Ojeda
- Centro Nacional de Microbiología, Instituto de Salud Carlos III (ISCIII), Majadahonda, Madrid, Spain
| | - Laura Aragoneses-Fenoll
- Centro Nacional de Microbiología, Instituto de Salud Carlos III (ISCIII), Majadahonda, Madrid, Spain
| | - Daniel López
- Centro Nacional de Microbiología, Instituto de Salud Carlos III (ISCIII), Majadahonda, Madrid, Spain
| | - Belén de Andrés
- Centro Nacional de Microbiología, Instituto de Salud Carlos III (ISCIII), Majadahonda, Madrid, Spain
| | - María Luisa Gaspar
- Centro Nacional de Microbiología, Instituto de Salud Carlos III (ISCIII), Majadahonda, Madrid, Spain
| | - Umberto Dianzani
- Interdisciplinary Research Center of Autoimmune Diseases (IRCAD) and Department of Health Sciences, University of Piemonte Orientale (UPO), Novara, Italy
| | - José M Rojo
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Pilar Portolés
- Centro Nacional de Microbiología, Instituto de Salud Carlos III (ISCIII), Majadahonda, Madrid, Spain
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Costimulation of type-2 innate lymphoid cells by GITR promotes effector function and ameliorates type 2 diabetes. Nat Commun 2019; 10:713. [PMID: 30755607 PMCID: PMC6372786 DOI: 10.1038/s41467-019-08449-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 01/07/2019] [Indexed: 12/27/2022] Open
Abstract
Metabolic syndrome is characterized by disturbances in glucose homeostasis and the development of low-grade systemic inflammation, which increase the risk to develop type 2 diabetes mellitus (T2DM). Type-2 innate lymphoid cells (ILC2s) are a recently discovered immune population secreting Th2 cytokines. While previous studies show how ILC2s can play a critical role in the regulation of metabolic homeostasis in the adipose tissue, a therapeutic target capable of modulating ILC2 activation has yet to be identified. Here, we show that GITR, a member of the TNF superfamily, is expressed on both murine and human ILC2s. Strikingly, we demonstrate that GITR engagement of activated, but not naïve, ILC2s improves glucose homeostasis, resulting in both protection against insulin resistance onset and amelioration of established insulin- resistance. Together, these results highlight the critical role of GITR as a novel therapeutic molecule against T2DM and its fundamental role as an immune checkpoint for activated ILC2s. Type-2 innate lymphoid cells (ILC2s) are an immune population secreting Th2 cytokines playing a role in the regulation of adipose metabolic homeostasis. Here the authors show that engagement of GITR, a member of the TNF superfamily, in activated ILC2s is protective against insulin resistance in both a preventive and a therapeutic manner in the context of obesity.
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Hurrell BP, Shafiei Jahani P, Akbari O. Social Networking of Group Two Innate Lymphoid Cells in Allergy and Asthma. Front Immunol 2018; 9:2694. [PMID: 30524437 PMCID: PMC6256740 DOI: 10.3389/fimmu.2018.02694] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 10/31/2018] [Indexed: 12/22/2022] Open
Abstract
Allergic diseases including asthma, chronic rhinosinusitis, and atopic dermatitis are common conditions worldwide. While type 2 immune responses induced by T-cells significantly cause allergic inflammation, the recently identified group two innate lymphoid cells (ILC2s) are emerging as critical players in the development of allergy. Upon allergen exposure, ILC2s are rapidly activated by cytokines released by epithelial cells. Activated ILC2s release various effector cytokines altogether contributing to the pathogenesis of allergy and can even cause inflammation in the absence of T-cells, as observed in asthma. Although the factors inducing ILC2 activation have been identified, evidence suggests that multiple factors can enhance or repress ILC2 proliferation, trafficking, or secretion of effector cytokines upon allergic inflammation. In this review, we discuss the recent findings that influence ILC2 activation and the resulting effects on the pathogenesis of allergy. A better understanding of how ILC2s are modulated will open the door to the development of new therapeutic strategies against allergic diseases.
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Affiliation(s)
- Benjamin P Hurrell
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Pedram Shafiei Jahani
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Omid Akbari
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
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Abstract
Innate lymphoid cells are functionally diverse subsets of immune cells including the conventional natural killer cells, lymphoid tissue inducers, type 1, 2, and 3 with significant roles in immunity and pathogenesis of inflammatory diseases. Type 2 innate lymphoid cells (ILC2s) resemble type 2 helper (Th2) cells in cytokine production and contribute to anti-helminth immunity, maintaining mucosal tissue integrity, and adipose tissue browning. ILC2s play important roles in the pathogenesis of allergic diseases and asthma. Studying the pathways of activation and regulation of ILC2s are currently a priority for giving a better understanding of pathogenesis of diseases with immunological roots. Recently, our laboratory and others have shown several pathways of regulation of ILC2s by co-stimulatory molecules such as ICOS, regulatory T cells and by compounds such as nicotine. In this review, we summarize the current understanding of the mechanisms of activation and regulation of ILC2s and the role of these cells in health and disease.
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Affiliation(s)
- Hadi Maazi
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, Los Angeles, California 90033, USA
| | - Omid Akbari
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, Los Angeles, California 90033, USA
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