1
|
Virtanen T. Inhalant Mammal-Derived Lipocalin Allergens and the Innate Immunity. FRONTIERS IN ALLERGY 2022; 2:824736. [PMID: 35387007 PMCID: PMC8974866 DOI: 10.3389/falgy.2021.824736] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 12/30/2021] [Indexed: 12/03/2022] Open
Abstract
A major part of important mammalian respiratory allergens belongs to the lipocalin family of proteins. By this time, 19 respiratory mammalian lipocalin allergens have been registered in the WHO/IUIS Allergen Nomenclature Database. Originally, lipocalins, small extracellular proteins (molecular mass ca. 20 kDa), were characterized as transport proteins but they are currently known to exert a variety of biological functions. The three-dimensional structure of lipocalins is well-preserved, and lipocalin allergens can exhibit high amino acid identities, in several cases more than 50%. Lipocalins contain an internal ligand-binding site where they can harbor small principally hydrophobic molecules. Another characteristic feature is their capacity to bind to specific cell-surface receptors. In all, the physicochemical properties of lipocalin allergens do not offer any straightforward explanations for their allergenicity. Allergic sensitization begins at epithelial barriers where diverse insults through pattern recognition receptors awaken innate immunity. This front-line response is manifested by epithelial barrier-associated cytokines which together with other components of immunity can initiate the sensitization process. In the following, the crucial factor in allergic sensitization is interleukin (IL)-4 which is needed for stabilizing and promoting the type 2 immune response. The source for IL-4 has been searched widely. Candidates for it may be non-professional antigen-presenting cells, such as basophils or mast cells, as well as CD4+ T cells. The synthesis of IL-4 by CD4+ T cells requires T cell receptor engagement, i.e., the recognition of allergen peptides, which also provides the specificity for sensitization. Lipocalin and innate immunity-associated cell-surface receptors are implicated in facilitating the access of lipocalin allergens into the immune system. However, the significance of this for allergic sensitization is unclear, as the recognition by these receptors has been found to produce conflicting results. As to potential adjuvants associated with mammalian lipocalin allergens, the hydrophobic ligands transported by lipocalins have not been reported to enhance sensitization while it is justified to suppose that lipopolysaccharide plays a role in it. Taken together, type 2 immunity to lipocalin allergens appears to be a harmful immune response resulting from a combination of signals involving both the innate and adaptive immunities.
Collapse
|
2
|
Virtanen T, Rytkönen-Nissinen M. Commentary: Allergen and Epitope Targets of Mouse-Specific T Cell Responses in Allergy and Asthma. Front Immunol 2019; 10:2266. [PMID: 31620142 PMCID: PMC6763578 DOI: 10.3389/fimmu.2019.02266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 09/09/2019] [Indexed: 11/13/2022] Open
Affiliation(s)
- Tuomas Virtanen
- Department of Clinical Microbiology, School of Medicine, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
| | - Marja Rytkönen-Nissinen
- Department of Clinical Microbiology, School of Medicine, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
| |
Collapse
|
3
|
Virtanen T. Reply to the letter to the editor concerning the review Immunotherapy for pet allergies. Hum Vaccin Immunother 2018; 14:1442-1443. [PMID: 29533130 PMCID: PMC6037453 DOI: 10.1080/21645515.2018.1449554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Affiliation(s)
- Tuomas Virtanen
- Clinical Microbiology, University of Eastern Finland, Kuopio, Finland
| |
Collapse
|
4
|
Santiago HDC, Nutman TB. Role in Allergic Diseases of Immunological Cross-Reactivity between Allergens and Homologues of Parasite Proteins. Crit Rev Immunol 2017; 36:1-11. [PMID: 27480900 DOI: 10.1615/critrevimmunol.2016016545] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Implied under the rubric of the hygiene hypothesis is that helminth infection can protect against allergic disease. It is well known that helminths induce processes associated with type 2 immune responses, but they also induce important regulatory responses that can modulate these type 2-associated responses-modulation that influences responses to bystander antigens including allergens. Indeed, most epidemiological studies demonstrate a beneficial effect of helminth infection on atopy, but there are also convincing data to demonstrate that helminth infection can precipitate or worsen allergic inflammation/disease. Reasons for these disparate findings are much debated, but there is a school of thought that suggests that helminth-triggered type 2-associated responses, including IgE to cross-reactive aeroallergens, can offset the regulatory effects imposed by the same organisms. The cross-reactivity among helminths and allergenic tropomyosins dominated the antigen/allergen cross-reactivity field, but recent data suggest that cross-reactivity is much more common than previously appreciated. It has been demonstrated that a high degree of molecular similarity exists between allergens and helminth proteins. Thus, an understanding of the mechanisms underlying the response induced by helminth infection and their impact on the induction of allergic disease in the host are critical for designing therapies using iatrogenic infections or parasite products to treat inflammatory diseases and for developing vaccines against helminth parasites.
Collapse
Affiliation(s)
- Helton da Costa Santiago
- Department of Biochemistry and Immunology, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Thomas B Nutman
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, USA
| |
Collapse
|
5
|
Jensen-Jarolim E, Pacios LF, Bianchini R, Hofstetter G, Roth-Walter F. Structural similarities of human and mammalian lipocalins, and their function in innate immunity and allergy. Allergy 2016; 71:286-94. [PMID: 26497994 PMCID: PMC4949658 DOI: 10.1111/all.12797] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/18/2015] [Indexed: 01/08/2023]
Abstract
Owners and their domestic animals via skin shedding and secretions, mutually exchange microbiomes, potential pathogens and innate immune molecules. Among the latter especially lipocalins are multifaceted: they may have an immunomodulatory function and, furthermore, they represent one of the most important animal allergen families. The amino acid identities, as well as their structures by superposition modeling were compared among human lipocalins, hLCN1 and hLCN2, and most important animal lipocalin allergens, such as Can f 1, Can f 2 and Can f 4 from dog, Fel d 4 from cats, Bos d 5 from cow's milk, Equ c 1 from horses, and Mus m 1 from mice, all of them representing major allergens. The β-barrel fold with a central molecular pocket is similar among human and animal lipocalins. Thereby, lipocalins are able to transport a variety of biological ligands in their highly conserved calyx-like cavity, among them siderophores with the strongest known capability to complex iron (Fe(3+) ). Levels of human lipocalins are elevated in nonallergic inflammation and cancer, associated with innate immunoregulatory functions that critically depend on ligand load. Accordingly, deficient loading of lipocalin allergens establishes their capacity to induce Th2 hypersensitivity. Our similarity analysis of human and mammalian lipocalins highlights their function in innate immunity and allergy.
Collapse
Affiliation(s)
- E Jensen-Jarolim
- The interuniversity Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University Vienna, University Vienna, Vienna, Austria
- Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University Vienna, Vienna, Austria
| | - L F Pacios
- Biotechnology Department, Center for Plant Biotechnology and Genomics, ETSI Montes, Technical University of Madrid, Madrid, Spain
- Department of Natural Systems and Resources, ETSI Montes, Technical University of Madrid, Madrid, Spain
| | - R Bianchini
- The interuniversity Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University Vienna, University Vienna, Vienna, Austria
| | - G Hofstetter
- The interuniversity Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University Vienna, University Vienna, Vienna, Austria
| | - F Roth-Walter
- The interuniversity Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University Vienna, University Vienna, Vienna, Austria
| |
Collapse
|
6
|
Rönkä AL, Kinnunen TT, Goudet A, Rytkönen-Nissinen MA, Sairanen J, Kailaanmäki AHT, Randell JT, Maillère B, Virtanen TI. Characterization of human memory CD4(+) T-cell responses to the dog allergen Can f 4. J Allergy Clin Immunol 2015; 136:1047-54.e10. [PMID: 25843313 DOI: 10.1016/j.jaci.2015.02.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 12/23/2014] [Accepted: 02/02/2015] [Indexed: 01/08/2023]
Abstract
BACKGROUND The recently identified dog lipocalin allergen Can f 4 is an important respiratory allergen. OBJECTIVE We sought to comprehensively characterize the memory CD4(+) T-cell responses of allergic and nonallergic subjects to Can f 4. METHODS Can f 4-specific CD4(+)CD45RO(+) T-cell lines (TCLs) from allergic and healthy subjects were established and characterized by their functional and phenotypic properties. The epitope specificity of the TCLs was tested with 48 overlapping 16-mer peptides spanning the sequence of Can f 4. HLA restriction of the specific TCLs and the binding capacity of the epitope-containing peptides to common HLA class II molecules were studied. RESULTS Can f 4-specific memory CD4(+) TCLs were obtained at an 8-fold higher frequency from allergic than from nonallergic subjects. Functionally, the TCLs of allergic subjects exhibited a higher T-cell receptor avidity and expression of CD25 and predominantly produced IL-4 and IL-5. The TCLs of nonallergic subjects mostly secreted IFN-γ and IL-10, with high CXCR3 expression. Several distinct T-cell epitope regions along the allergen were identified. Importantly, the peptides from the region between amino acids 43 and 67 showed promiscuous HLA-binding capacity and induced memory CD4(+) T-cell responses in 90% of the allergic donors. CONCLUSION Productive TH2-deviated memory T-cell responses to Can f 4 are observed in allergic but not nonallergic subjects. A 19-mer peptide sequence covering the core of the immunodominant region of the allergen is a potential target for the development of peptide-based allergen immunotherapy.
Collapse
Affiliation(s)
- Aino L Rönkä
- Department of Clinical Microbiology, Institute of Clinical Medicine and Biocenter Kuopio, University of Eastern Finland, Kuopio, Finland.
| | - Tuure T Kinnunen
- Department of Clinical Microbiology, Institute of Clinical Medicine and Biocenter Kuopio, University of Eastern Finland, Kuopio, Finland
| | - Amélie Goudet
- Commissariat à l'Energie Atomique, Institut de Biologie et de Technologies, Service d'Ingénierie Moléculaire des Protéines, Gif-Sur-Yvette, France
| | - Marja A Rytkönen-Nissinen
- Department of Clinical Microbiology, Institute of Clinical Medicine and Biocenter Kuopio, University of Eastern Finland, Kuopio, Finland; Institute of Dentistry, School of Medicine, University of Eastern Finland, Kuopio, Finland
| | - Joni Sairanen
- Department of Clinical Microbiology, Institute of Clinical Medicine and Biocenter Kuopio, University of Eastern Finland, Kuopio, Finland
| | - Anssi H T Kailaanmäki
- Department of Clinical Microbiology, Institute of Clinical Medicine and Biocenter Kuopio, University of Eastern Finland, Kuopio, Finland
| | - Jukka T Randell
- Department of Pulmonary Diseases, Kuopio University Hospital, Kuopio, Finland
| | - Bernard Maillère
- Commissariat à l'Energie Atomique, Institut de Biologie et de Technologies, Service d'Ingénierie Moléculaire des Protéines, Gif-Sur-Yvette, France
| | - Tuomas I Virtanen
- Department of Clinical Microbiology, Institute of Clinical Medicine and Biocenter Kuopio, University of Eastern Finland, Kuopio, Finland
| |
Collapse
|
7
|
Liukko ALK, Kinnunen TT, Rytkönen-Nissinen MA, Kailaanmäki AHT, Randell JT, Maillère B, Virtanen TI. Human CD4+ T cell responses to the dog major allergen Can f 1 and its human homologue tear lipocalin resemble each other. PLoS One 2014; 9:e98461. [PMID: 24875388 PMCID: PMC4038554 DOI: 10.1371/journal.pone.0098461] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 05/03/2014] [Indexed: 01/21/2023] Open
Abstract
Lipocalin allergens form a notable group of proteins, as they contain most of the significant respiratory allergens from mammals. The basis for the allergenic capacity of allergens in the lipocalin family, that is, the development of T-helper type 2 immunity against them, is still unresolved. As immunogenicity has been proposed to be a decisive feature of allergens, the purpose of this work was to examine human CD4+ T cell responses to the major dog allergen Can f 1 and to compare them with those to its human homologue, tear lipocalin (TL). For this, specific T cell lines were induced in vitro from the peripheral blood mononuclear cells of Can f 1-allergic and healthy dog dust-exposed subjects with peptides containing the immunodominant T cell epitopes of Can f 1 and the corresponding TL peptides. We found that the frequency of Can f 1 and TL-specific T cells in both subject groups was low and close to each other, the difference being about two-fold. Importantly, we found that the proliferative responses of both Can f 1 and TL-specific T cell lines from allergic subjects were stronger than those from healthy subjects, but that the strength of the responses within the subject groups did not differ between these two antigens. Moreover, the phenotype of the Can f 1 and TL-specific T cell lines, determined by cytokine production and expression of cell surface markers, resembled each other. The HLA system appeared to have a minimal role in explaining the allergenicity of Can f 1, as the allergic and healthy subjects' HLA background did not differ, and HLA binding was very similar between Can f 1 and TL peptides. Along with existing data on lipocalin allergens, we conclude that strong antigenicity is not decisive for the allergenicity of Can f 1.
Collapse
Affiliation(s)
- Aino L. K. Liukko
- Department of Clinical Microbiology, Institute of Clinical Medicine and Biocenter Kuopio, University of Eastern Finland, Kuopio, Finland
| | - Tuure T. Kinnunen
- Department of Clinical Microbiology, Institute of Clinical Medicine and Biocenter Kuopio, University of Eastern Finland, Kuopio, Finland
| | - Marja A. Rytkönen-Nissinen
- Department of Clinical Microbiology, Institute of Clinical Medicine and Biocenter Kuopio, University of Eastern Finland, Kuopio, Finland
- Institute of Dentistry, School of Medicine, University of Eastern Finland, Kuopio, Finland
| | - Anssi H. T. Kailaanmäki
- Department of Clinical Microbiology, Institute of Clinical Medicine and Biocenter Kuopio, University of Eastern Finland, Kuopio, Finland
| | - Jukka T. Randell
- Department of Pulmonary Diseases, Kuopio University Hospital, Kuopio, Finland
| | - Bernard Maillère
- Commissariat à l'Energie Atomique, Institut de Biologie et de Technologies, Service d'Ingénierie Moléculaire des Protéines, Gif Sur Yvette, France
| | - Tuomas I. Virtanen
- Department of Clinical Microbiology, Institute of Clinical Medicine and Biocenter Kuopio, University of Eastern Finland, Kuopio, Finland
| |
Collapse
|
8
|
Kailaanmäki A, Kinnunen T, Kwok WW, Rytkönen-Nissinen M, Randell J, Virtanen T. Differential CD4+ T-cell responses of allergic and non-allergic subjects to the immunodominant epitope region of the horse major allergen Equ c 1. Immunology 2014; 141:52-60. [PMID: 23991693 DOI: 10.1111/imm.12166] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 08/26/2013] [Accepted: 08/28/2013] [Indexed: 12/16/2022] Open
Abstract
The responses of allergen-specific CD4(+) T cells of allergic and healthy individuals are still incompletely understood. Our objective was to investigate the functional and phenotypic properties of CD4(+) T cells of horse-allergic and healthy subjects specific to the immunodominant epitope region of the major horse allergen Equ c 1. Specific T-cell lines (TCLs) and clones were generated from peripheral blood mononuclear cells with Equ c 1(143-160), the peptide containing the immunodominant epitope region of Equ c 1. The frequency, proliferative response, cytokine production and HLA restriction of the cells were examined. The frequency of Equ c 1-specific CD4(+) T cells was low (approximately 1 per 10(6) CD4(+) T cells) in both allergic and non-allergic subjects. The cells of allergic subjects had a stronger proliferative capacity than those of non-allergic subjects, and they predominantly emerged from the memory T-cell pool and expressed the T helper type 2 cytokine profile, whereas the cells of non-allergic subjects emerged from the naive T-cell pool and produced low levels of interferon-γ and interleukin-10. T-cell response to Equ c 1(143-160) was restricted by several common HLA class II molecules from both DQ and DR loci. As the phenotypic and functional properties of Equ c 1-specific CD4(+) T cells differ between allergic and non-allergic subjects, allergen-specific T cells appear to be tightly implicated in the development of diseased or healthy outcome. Restriction of the specific CD4(+) T-cell response by multiple HLA alleles suggests that Equ c 1(143-160) is a promising candidate for peptide-based immunotherapy.
Collapse
Affiliation(s)
- Anssi Kailaanmäki
- Department of Clinical Microbiology, Institute of Clinical Medicine and Biocentre Kuopio, University of Eastern Finland, Kuopio, Finland
| | | | | | | | | | | |
Collapse
|
9
|
Virtanen T, Kinnunen T, Rytkönen-Nissinen M. Mammalian lipocalin allergens--insights into their enigmatic allergenicity. Clin Exp Allergy 2011; 42:494-504. [PMID: 22093088 DOI: 10.1111/j.1365-2222.2011.03903.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 08/29/2011] [Accepted: 10/08/2011] [Indexed: 01/14/2023]
Abstract
Most of the important mammal-derived respiratory allergens, as well as a milk allergen and a few insect allergens, belong to the lipocalin protein family. As mammalian lipocalin allergens are found in dander, saliva and urine, they disperse effectively and are widely present in the indoor environments. Initially, lipocalins were characterized as transport proteins for small, principally hydrophobic molecules, but now they are known to be involved in many other biological functions. Although the amino acid identity between lipocalins is generally at the level of 20-30%, it can be considerably higher. Lipocalin allergens do not exhibit any known physicochemical, functional or structural property that would account for their allergenicity, that is, the capacity to induce T-helper type 2 immunity against them. A distinctive feature of mammalian lipocalin allergens is their poor capacity to stimulate the cellular arm of the human or murine immune system. Nevertheless, they induce IgE production in a large proportion of atopic individuals exposed to the allergen source. The poor capacity of mammalian lipocalin allergens to stimulate the cellular immune system does not appear to result from the function of regulatory T cells. Instead, the T cell epitopes of mammalian lipocalin allergens are few and those examined have proved to be suboptimal. Moreover, the frequency of mammalian lipocalin allergen-specific CD4(+) T cells is very low in the peripheral blood. Importantly, recent research suggests that the lipocalin allergen-specific T cell repertoires differ considerably between allergic and healthy subjects. These observations are compatible with our hypothesis that the way CD4(+) T-helper cells recognize the epitopes of mammalian lipocalin allergens may be implicated in their allergenicity. Indeed, as several lipocalins exhibit homologies of 40-60% over species, mammalian lipocalin allergens may be immunologically at the borderline of self and non-self, which would not allow a strong anti-allergenic immune response against them.
Collapse
Affiliation(s)
- T Virtanen
- Department of Clinical Microbiology, School of Medicine, University of Eastern Finland, Kuopio, Finland.
| | | | | |
Collapse
|
10
|
Current world literature. Curr Opin Allergy Clin Immunol 2010; 10:603-7. [PMID: 21030837 DOI: 10.1097/aci.0b013e3283413126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|