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3.
J Allergy Clin Immunol ; 138(4): 984-1010, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27577879

RESUMO

There have been extensive developments on cellular and molecular mechanisms of immune regulation in allergy, asthma, autoimmune diseases, tumor development, organ transplantation, and chronic infections during the last few years. Better understanding the functions, reciprocal regulation, and counterbalance of subsets of immune and inflammatory cells that interact through interleukins, interferons, TNF-α, and TGF-ß offer opportunities for immune interventions and novel treatment modalities in the era of development of biological immune response modifiers particularly targeting these molecules or their receptors. More than 60 cytokines have been designated as interleukins since the initial discoveries of monocyte and lymphocyte interleukins (called IL-1 and IL-2, respectively). Studies of transgenic or gene-deficient mice with altered expression of these cytokines or their receptors and analyses of mutations and polymorphisms in human genes that encode these products have provided essential information about their functions. Here we review recent developments on IL-1 to IL-38, TNF-α, TGF-ß, and interferons. We highlight recent advances during the last few years in this area and extensively discuss their cellular sources, targets, receptors, signaling pathways, and roles in immune regulation in patients with allergy and asthma and other inflammatory diseases.


Assuntos
Doenças do Sistema Imunitário , Interferons/fisiologia , Interleucinas/fisiologia , Linfócitos T Reguladores/imunologia , Fator de Crescimento Transformador beta/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Humanos
4.
PLoS One ; 11(5): e0156077, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27228091

RESUMO

BACKGROUND: Atopic dermatitis (AD) is a complex chronic inflammatory disease where allergens can act as specific triggering factors. AIM: To characterize the specificities of IgE-reactivity in patients with AD to a broad panel of exogenous allergens including microbial and human antigens. METHODOLOGY: Adult patients with AD were grouped according to the SCORAD index, into severe (n = 53) and moderate AD (n = 126). As controls 43 patients were included with seborrhoeic eczema and 97 individuals without history of allergy or skin diseases. Specific IgE reactivity was assessed in plasma using Phadiatop®, ImmunoCap™, micro-arrayed allergens, dot-blotted recombinant Malassezia sympodialis allergens, and immune-blotted microbial and human proteins. RESULTS: IgE reactivity was detected in 92% of patients with severe and 83% of patients with moderate AD. Sensitization to cat allergens occurred most frequently, followed by sensitization to birch pollen, grass pollen, and to the skin commensal yeast M. sympodialis. Patients with severe AD showed a significantly higher frequency of IgE reactivity to allergens like cat (rFel d 1) and house dust mite (rDer p 4 and 10), to Staphylococcus aureus, M. sympodialis, and to human antigens. In contrast, there were no significant differences in the frequencies of IgE reactivity to the grass pollen allergens rPhl p 1, 2, 5b, and 6 between the two AD groups. Furthermore the IgE reactivity profile of patients with severe AD was more spread towards several different allergen molecules as compared to patients with moderate AD. CONCLUSION: We have revealed a hitherto unknown difference regarding the molecular sensitization profile in patients with severe and moderate AD. Molecular profiling towards allergen components may provide a basis for future investigations aiming to explore the environmental, genetic and epigenetic factors which could be responsible for the different appearance and severity of disease phenotypes in AD.


Assuntos
Alérgenos/imunologia , Dermatite Atópica/imunologia , Imunoglobulina E/imunologia , Malassezia/imunologia , Staphylococcus aureus/imunologia , Adolescente , Adulto , Idoso , Animais , Biomarcadores/sangue , Estudos de Casos e Controles , Gatos , Dermatite Atópica/sangue , Dermatite Atópica/diagnóstico , Feminino , Humanos , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/imunologia , Testes Cutâneos , Adulto Jovem
5.
J Immunol ; 194(12): 5895-902, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25941327

RESUMO

The development of vaccines inducing efficient CD8(+) T cell responses is the focus of intense research. Dendritic cells (DCs) expressing the XCR1 chemokine receptor, also known as CD103(+) or CD8α(+) DCs, excel in the presentation of extracellular Ags to CD8(+) T cells. Because of its high numbers of DCs, including XCR1(+) DCs, the skin dermis is an attractive site for vaccine administration. By creating laser-generated micropores through the epidermis, we targeted a model protein Ag fused to XCL1, the ligand of XCR1, to dermal XCR1(+) DCs and induced Ag-specific CD8(+) and CD4(+) T cell responses. Efficient immunization required the emigration of XCR1(+) dermal DCs to draining lymph nodes and occurred irrespective of TLR signaling. Moreover, a single intradermal immunization protected mice against melanoma tumor growth in prophylactic and therapeutic settings, in the absence of exogenous adjuvant. The mild inflammatory milieu created in the dermis by skin laser microporation itself most likely favored the development of potent T cell responses in the absence of exogenous adjuvants. The existence of functionally equivalent XCR1(+) dermal DCs in humans should permit the translation of laser-assisted intradermal delivery of a tumor-specific vaccine targeting XCR1(+) DCs to human cancer immunotherapy. Moreover, considering that the use of adjuvants in vaccines is often associated with safety issues, the possibility of inducing protective responses against melanoma tumor growth independently of the administration of exogenous adjuvants should facilitate the development of safer vaccines.


Assuntos
Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Neoplasias/imunologia , Receptores de Quimiocinas/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Vacinas Anticâncer/administração & dosagem , Quimiocinas C/genética , Quimiocinas C/metabolismo , Modelos Animais de Doenças , Injeções Intradérmicas , Melanoma Experimental , Camundongos , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Ovalbumina/genética , Ovalbumina/imunologia , Ligação Proteica , Receptores de Quimiocinas/genética , Subpopulações de Linfócitos T/imunologia , Carga Tumoral/imunologia
6.
Semin Immunopathol ; 37(2): 117-21, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25413498

RESUMO

Despite the increasing number of solved crystal structures of allergens, the key question why some proteins are allergenic and the vast majority is not remains unanswered. The situation is not different for fungal allergens which cover a wide variety of proteins with different chemical properties and biological functions. They cover enzymes, cell wall, secreted, and intracellular proteins which, except cross-reactive allergens, does not show any evidence for structural similarities at least at the three-dimensional level. However, from a diagnostic point of view, pure allergens biotechnologically produced by recombinant technology can provide us, in contrast to fungal extracts which are hardly producible as standardized reagents, with highly pure perfectly standardized diagnostic reagents.


Assuntos
Alérgenos/química , Alérgenos/imunologia , Antígenos de Fungos/química , Antígenos de Fungos/imunologia , Fungos/imunologia , Reações Cruzadas/imunologia , Fungos/metabolismo , Humanos , Hipersensibilidade/imunologia , Hipersensibilidade/metabolismo , Modelos Moleculares , Estrutura Molecular
8.
Am J Respir Crit Care Med ; 187(6): 621-9, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23306544

RESUMO

RATIONALE: Cystic fibrosis (CF) is characterized by progressive pulmonary inflammation that is infection-triggered. Pseudomonas aeruginosa represents a risk factor for deterioration of lung function and reduced life expectancy. OBJECTIVES: To assess T-cell cytokine/chemokine production in clinically stable children with CF and evaluate the association between T-cell subtypes and susceptibility for infection with P. aeruginosa. METHODS: T-cell cytokine/chemokine profiles were measured in bronchoalveolar lavage fluid (BALF) from children with CF (n = 57; 6.1 ± 5.9 yr) and non-CF control subjects (n = 18; 5.9 ± 4.3 yr). Memory responses to Aspergillus fumigatus and P. aeruginosa were monitored. High-resolution computed tomography-based Helbich score was assessed. In a prospective observational trial the association between BALF cytokine/chemokine profiles and subsequent infection with P. aeruginosa was studied. MEASUREMENTS AND MAIN RESULTS: Th1- (INF-γ), Th2- (IL-5, IL-13), Th17- (IL-17A), and Th17-related cytokines (IL-1ß, IL-6) were significantly up-regulated in airways of patients with CF. IL-17A, IL-13, and IL-5 were significantly higher in BALF of symptomatic as compared with clinically asymptomatic patients with CF. IL-17A and IL-5 correlated with the percentage of neutrophils in BALF (r = 0.41, P < 0.05 and r = 0.46, P < 0.05, respectively). Th17- (IL-17A, IL-6, IL-1ß, IL-8) and Th2-associated cytokines and chemokines (IL-5, IL-13, TARC/CCL17), but not IFN-γ levels, significantly correlated with high-resolution computed tomography changes (Helbich score; P < 0.05). P. aeruginosa- and A. fumigatus-specific T cells from patients with CF displayed significantly higher IL-5 and IL-17A mRNA expression. IL-17A and TARC/CCL17 were significantly augmented in patients that developed P. aeruginosa infection within 24 months. CONCLUSIONS: We propose a role for Th17 and Th2 T cells in chronic inflammation in lungs of patients with CF. High concentrations of these cytokines/chemokines in CF airways precede infection with P. aeruginosa.


Assuntos
Fibrose Cística/metabolismo , Citocinas/metabolismo , Infecções por Pseudomonas/metabolismo , Pseudomonas aeruginosa , Células Th17/metabolismo , Células Th2/metabolismo , Adolescente , Líquido da Lavagem Broncoalveolar , Criança , Pré-Escolar , Feminino , Humanos , Interferon gama/metabolismo , Masculino , Prognóstico , Estudos Prospectivos
9.
J Allergy Clin Immunol ; 129(5): 1290-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22464647

RESUMO

BACKGROUND: Subcutaneous allergen-specific immunotherapy frequently causes allergic side effects and requires 30 to 80 injections over 3 to 5 years. OBJECTIVE: We sought to improve immunotherapy by using intralymphatic allergen administration (intralymphatic immunotherapy [ILIT]) and by targeting allergen to the MHC class II pathway. METHODS: Recombinant major cat dander allergen Fel d 1 was fused to a translocation sequence (TAT) and to part of the human invariant chain, generating a modular antigen transporter (MAT) vaccine (MAT-Fel d 1). In a randomized double-blind trial ILIT with MAT-Fel d 1 in alum was compared with ILIT with placebo (saline in alum) in allergic patients (ClinicalTrials.govNCT00718679). RESULTS: ILIT with MAT-Fel d 1 elicited no adverse events. After 3 placebo injections within 2 months, nasal tolerance increased less than 3-fold, whereas 3 intralymphatic injections with MAT-Fel d 1 increased nasal tolerance 74-fold (P < .001 vs placebo). ILIT with MAT-Fel d 1 stimulated regulatory T-cell responses (P = .026 vs placebo) and increased cat dander-specific IgG(4) levels by 5.66-fold (P = .003). The IgG(4) response positively correlated with IL-10 production (P < .001). CONCLUSION: In a first-in-human clinical study ILIT with MAT-Fel d 1 was safe and induced allergen tolerance after 3 injections.


Assuntos
Alérgenos/administração & dosagem , Dessensibilização Imunológica , Glicoproteínas/administração & dosagem , Hipersensibilidade/tratamento farmacológico , Linfócitos T Reguladores/efeitos dos fármacos , Adulto , Alérgenos/efeitos adversos , Alérgenos/genética , Alérgenos/metabolismo , Animais , Formação de Anticorpos/efeitos dos fármacos , Antígenos de Diferenciação de Linfócitos B/genética , Antígenos de Diferenciação de Linfócitos B/metabolismo , Gatos , Células Cultivadas , Feminino , Glicoproteínas/efeitos adversos , Glicoproteínas/genética , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Hipersensibilidade/diagnóstico , Hipersensibilidade/imunologia , Hipersensibilidade/fisiopatologia , Imunoglobulina G/sangue , Injeções Intralinfáticas , Interleucina-10/metabolismo , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/genética , Engenharia de Proteínas , Proteínas Recombinantes de Fusão/genética , Testes Cutâneos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia , Adulto Jovem
10.
PLoS One ; 6(9): e24558, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21931754

RESUMO

Allergy and asthma to cat (Felis domesticus) affects about 10% of the population in affluent countries. Immediate allergic symptoms are primarily mediated via IgE antibodies binding to B cell epitopes, whereas late phase inflammatory reactions are mediated via activated T cell recognition of allergen-specific T cell epitopes. Allergen-specific immunotherapy relieves symptoms and is the only treatment inducing a long-lasting protection by induction of protective immune responses. The aim of this study was to produce an allergy vaccine designed with the combined features of attenuated T cell activation, reduced anaphylactic properties, retained molecular integrity and induction of efficient IgE blocking IgG antibodies for safer and efficacious treatment of patients with allergy and asthma to cat. The template gene coding for rFel d 1 was used to introduce random mutations, which was subsequently expressed in large phage libraries. Despite accumulated mutations by up to 7 rounds of iterative error-prone PCR and biopanning, surface topology and structure was essentially maintained using IgE-antibodies from cat allergic patients for phage enrichment. Four candidates were isolated, displaying similar or lower IgE binding, reduced anaphylactic activity as measured by their capacity to induce basophil degranulation and, importantly, a significantly lower T cell reactivity in lymphoproliferative assays compared to the original rFel d 1. In addition, all mutants showed ability to induce blocking antibodies in immunized mice.The approach presented here provides a straightforward procedure to generate a novel type of allergy vaccines for safer and efficacious treatment of allergic patients.


Assuntos
Dessensibilização Imunológica/métodos , Hipersensibilidade/imunologia , Sequência de Aminoácidos , Animais , Linfócitos B/imunologia , Basófilos/imunologia , Gatos , Escherichia coli/metabolismo , Feminino , Biblioteca Gênica , Humanos , Hipersensibilidade/terapia , Imunoglobulina E/química , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Mutação , Biblioteca de Peptídeos , Homologia de Sequência de Aminoácidos , Linfócitos T/imunologia
11.
J Allergy Clin Immunol ; 128(1): 92-99.e4, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21489611

RESUMO

BACKGROUND: IgE-mediated cross-reactivity between fungal antigens and human proteins has been described in patients with atopic dermatitis (AD), but it remains to be elucidated whether there is also cross-reactivity at the T-cell level. OBJECTIVE: We sought to explore cross-reactivity at the T-cell level between the fungal thioredoxin (Mala s 13) of the skin-colonizing yeast Malassezia sympodialis and its homologous human thioredoxin (hTrx). METHODS: T-cell lines (TCLs) were generated in the presence of rMala s 13 from the peripheral blood and from skin biopsy specimens of positive patch test reactions of patients with AD sensitized to Mala s 13 and hTrx. Patients with AD not sensitized to Malassezia species, healthy subjects, and patients with psoriasis served as control subjects. Mala s 13-specific T-cell clones (TCCs) were generated from TCLs. TCCs were characterized by antigen specificity, phenotype, and cytokine secretion pattern. Human keratinocytes were stimulated with IFN-γ, TNF-α, and IL-4, and the release of hTrx was determined by means of ELISA. RESULTS: Mala s 13-specific TCLs and TCCs from the blood and skin of patients with AD sensitized to Mala s 13 and hTrx were fully cross-reactive with hTrx. Mala s 13- and hTrx-specific TCCs could not be generated from control subjects. The majority of cross-reactive TCCs were CD4(+) and coexpressed cutaneous lymphocyte antigen. In addition to T(H)1 and T(H)2 TCCs, we could also identify TCCs secreting IL-17 and IL-22. After stimulation with IFN-γ and TNF-α, keratinocytes released substantial amounts of thioredoxin. CONCLUSION: In patients with AD sensitized to Malassezia species, cross-reactivity at the T-cell level to Mala s 13 and the homologous hTrx is detectable. hTrx autoreactive skin-homing T cells might be relevant for cutaneous inflammation in patients with AD.


Assuntos
Autoimunidade/imunologia , Dermatite Atópica/imunologia , Malassezia/imunologia , Linfócitos T/imunologia , Tiorredoxinas/imunologia , Adulto , Idoso , Antígenos de Fungos/imunologia , Autoantígenos/imunologia , Reações Cruzadas , Dermatite Atópica/microbiologia , Dermatomicoses/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Adulto Jovem
12.
J Allergy Clin Immunol ; 127(3): 701-21.e1-70, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21377040

RESUMO

Advancing our understanding of mechanisms of immune regulation in allergy, asthma, autoimmune diseases, tumor development, organ transplantation, and chronic infections could lead to effective and targeted therapies. Subsets of immune and inflammatory cells interact via ILs and IFNs; reciprocal regulation and counter balance among T(h) and regulatory T cells, as well as subsets of B cells, offer opportunities for immune interventions. Here, we review current knowledge about ILs 1 to 37 and IFN-γ. Our understanding of the effects of ILs has greatly increased since the discoveries of monocyte IL (called IL-1) and lymphocyte IL (called IL-2); more than 40 cytokines are now designated as ILs. Studies of transgenic or knockout mice with altered expression of these cytokines or their receptors and analyses of mutations and polymorphisms in human genes that encode these products have provided important information about IL and IFN functions. We discuss their signaling pathways, cellular sources, targets, roles in immune regulation and cellular networks, roles in allergy and asthma, and roles in defense against infections.


Assuntos
Doenças do Sistema Imunitário , Interferon gama/fisiologia , Interleucinas/imunologia , Receptores de Interferon/imunologia , Receptores de Interleucina/imunologia , Animais , Humanos , Doenças do Sistema Imunitário/etiologia , Doenças do Sistema Imunitário/imunologia , Interleucinas/classificação , Camundongos
13.
Eur J Immunol ; 41(4): 1058-69, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21337543

RESUMO

HIV infection is characterized by sustained immune activation, which is reflected by activated T cells and, in particular, by increased levels of phosphorylated STAT proteins. Here, we hypothesized that T-cell activation in HIV infection is partially due to the inability of SOCS-1 and SOCS-3 to control the JAK/STAT pathway. We found higher levels of SOCS-1/3 mRNA levels in CD4(+) T cells of HIV-infected patients than in healthy controls. However, SOCS protein levels were lower, explaining the lack of attenuation of the JAK/STAT pathway. Infection of CD4(+) T cells alone did not activate STATs, while ex vivo infection of PBMC did, indicating that non-T cells critical for shaping the immune response, e.g. DC were responsible for the STAT-1 activation. Supernatants from ex vivo-infected PBMC transferred to CD4(+) T cells induced JAK/STAT activation, pointing to a central role of soluble factors. Notably, over-expression of SOCS-1/3 in CD4(+) T cells prevented JAK/STAT activation. Thus, HIV infection interferes with SOCS-1/3 expression driving immune activation. Sustained immune activation disrupts the lymphoid system and favors HIV replication since HIV preferentially infects activated cells. We speculate that regulating SOCS may be a potential way to counteract immune activation in HIV disease.


Assuntos
Infecções por HIV/imunologia , Proteínas Supressoras da Sinalização de Citocina/imunologia , Adulto , Células Cultivadas , Regulação da Expressão Gênica , Infecções por HIV/metabolismo , Humanos , Janus Quinases/metabolismo , Pessoa de Meia-Idade , RNA Mensageiro/genética , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Proteína 1 Supressora da Sinalização de Citocina , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/genética , Linfócitos T/imunologia
14.
Vet Immunol Immunopathol ; 139(2-4): 200-9, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21071100

RESUMO

Salivary gland proteins of Culicoides spp. have been suggested to be among the main allergens inducing IgE-mediated insect bite hypersensitivity (IBH), an allergic dermatitis of the horse. The aim of our study was to identify, produce and characterize IgE-binding salivary gland proteins of Culicoides nubeculosus relevant for IBH by phage surface display technology. A cDNA library constructed with mRNA derived from C. nubeculosus salivary glands was displayed on the surface of filamentous phage M13 and enriched for clones binding serum IgE of IBH-affected horses. Ten cDNA inserts encoding putative salivary gland allergens were isolated and termed Cul n 2 to Cul n 11. However, nine cDNA sequences coded for truncated proteins as determined by database searches. The cDNA sequences were amplified by PCR, subcloned into high level expression vectors and expressed as hexahistidine-tagged fusion proteins in Escherichia coli. Preliminary ELISA results obtained with these fusions confirmed the specific binding to serum IgE of affected horses. Therefore, the putative complete open reading frames derived from BLAST analyses were isolated by RACE-PCR and subcloned into expression vectors. The full length proteins expressed in Escherichia coli showed molecular masses in the range of 15.5-68.7 kDa in SDS-PAGE in good agreement with the masses calculated from the predicted protein sequences. Western blot analyses of all recombinant allergens with a serum pool of IBH-affected horses showed their ability to specifically bind serum IgE of sensitized horses, and ELISA determinations yielded individual horse recognition patterns with a frequency of sensitization ranging from 13 to 57%, depending on the allergen tested. The in vivo relevance of eight of the recombinant allergens was demonstrated in intradermal skin testing. For the two characterized allergens Cul n 6 and Cul n 11, sensitized horses were not available for intradermal tests. Control horses without clinical signs of IBH did not develop any relevant immediate hypersensitivity reactions to the recombinant allergens. The major contribution of this study was to provide a repertoire of recombinant salivary gland allergens repertoire from C. nubeculosus potentially involved in the pathogenesis of IBH as a starting basis for the development of a component-resolved serologic diagnosis of IBH and, perhaps, for the development of single horse tailored specific immunotherapy depending on their component-resolved sensitization patterns.


Assuntos
Alérgenos/metabolismo , Ceratopogonidae , Clonagem Molecular , Doenças dos Cavalos/imunologia , Hipersensibilidade/veterinária , Mordeduras e Picadas de Insetos/veterinária , Glândulas Salivares/metabolismo , Alérgenos/imunologia , Animais , Sequência de Bases , DNA/genética , Biblioteca Gênica , Cavalos , Hipersensibilidade/imunologia , Imunoglobulina E , Mordeduras e Picadas de Insetos/imunologia , Testes Intradérmicos/veterinária , Camundongos , Ligação Proteica , Testes Cutâneos/veterinária
15.
Eur J Immunol ; 40(11): 3161-72, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20865787

RESUMO

HAX1 was originally described as HS1-associated protein with a suggested function in receptor-mediated apoptotic and proliferative responses of lymphoid cells. Recent publications refer to a complex and multifunctional role of this protein. To investigate the in vivo function of HAX1 (HS1-associated protein X1) in B cells, we generated a Hax1-deficient mouse strain. Targeted deletion of Hax1 resulted in premature death around the age of 12 wk accompanied by a severe reduction of lymphocytes in spleen, thymus and bone marrow. In the bone marrow, all B-cell populations were lost comparably. In the spleen, B220(+) cells were reduced by almost 70%. However, as investigated by adoptive transfer experiments, this impairment is not exclusively B-cell intrinsic and we hypothesize that a HAX1-deficient environment cannot sufficiently provide the essential factors for proper lymphocyte development, trafficking and survival. Hax1(-/-) B cells show a significantly reduced expression of CXCR4, which might have an influence on the observed defects in B-cell development.


Assuntos
Linfócitos B/imunologia , Movimento Celular/imunologia , Linfopoese/imunologia , Proteínas/imunologia , Animais , Linfócitos B/metabolismo , Medula Óssea/imunologia , Medula Óssea/metabolismo , Movimento Celular/genética , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/imunologia , Peptídeos e Proteínas de Sinalização Intracelular , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/imunologia , Antígenos Comuns de Leucócito/metabolismo , Linfopoese/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Proteínas/genética , Proteínas/metabolismo , Receptores CXCR4/biossíntese , Receptores CXCR4/genética , Receptores CXCR4/imunologia , Baço/imunologia , Baço/metabolismo , Timo/imunologia , Timo/metabolismo
16.
Autoimmunity ; 43(7): 493-503, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20380589

RESUMO

The immune response is a tightly regulated process, which normally results in protection from infection and tolerance of innocuous environmental antigens. However, in allergic disease, the activated immune response results in a chronic pro-inflammatory state characterized by antibody secretion (IgE) and T cell activation to normally well-tolerated antigens. Currently, the treatment of allergic disease is focused on the suppression of key inflammatory mediators or inflammatory cell populations and include anti-histamines, anti-leukotrienes, β2 adrenergic receptor agonists and corticosteroids. However, these approaches only provide a temporary suppression of disease symptoms. Successful long-term treatment can only be provided by allergen-specific immunotherapy (allergen-SIT), which restores normal immunity against allergens. This review will discuss novel approaches to the management of allergy and asthma by targeting the T regulatory cell via modulation of the commensal microbiota and allergen-SIT.


Assuntos
Asma/imunologia , Asma/terapia , Hipersensibilidade/imunologia , Hipersensibilidade/terapia , Imunoterapia/métodos , Animais , Humanos
17.
Curr Opin Allergy Clin Immunol ; 9(6): 568-73, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19680120

RESUMO

PURPOSE OF REVIEW: The purpose of the present review is to describe recent approaches aimed at improving the treatment of allergic diseases through allergen-specific immunotherapy (SIT). Special emphasis will be given to the approach based on specific targeting of the major histocompatibility complex (MHC) class-II antigen-presentation pathway. RECENT FINDINGS: It is well recognized that IgE-mediated allergic diseases including rhinitis, atopic eczema and allergic asthma are increasing worldwide to a pandemic dimension. The only curative treatment remains allergen-SIT, which, however, requires a long treatment time of 3-5 years with up to 80 injections to confer protection. Recent findings strongly indicate that the treatment time and the number of injections could be drastically reduced by turning immunotherapy to a true vaccination. Direct injection of allergen extracts into the inguinal lymph nodes and targeting the MHC class-II antigen-presentation pathway by recombinant modular antigen-translocating vaccines have the potential to cure allergic diseases in a very short time. SUMMARY: The mechanisms of allergic inflammation can be divided into four distinct stages: T cell activation, organ-selective homing, survival/reactivation and effector functions. On the basis of this new knowledge several novel concepts aimed at treating allergic diseases have been developed. The area of allergen-SIT is experiencing exciting developments. Reciprocal regulation of effector and regulatory T cell subsets is being more and more used to develop novel strategies for immunomodulation.


Assuntos
Alérgenos/administração & dosagem , Dessensibilização Imunológica , Hipersensibilidade Imediata/terapia , Alérgenos/imunologia , Apresentação de Antígeno , Vias de Administração de Medicamentos , Sistemas de Liberação de Medicamentos , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Hipersensibilidade Imediata/imunologia , Imunomodulação , Transporte Proteico , Vacinas , Vacinas Sintéticas
18.
J Allergy Clin Immunol ; 124(2): 278-85, 285.e1-7, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19541355

RESUMO

BACKGROUND: Atopic eczema (AE) is the most common chronic inflammatory skin disease. Recent data demonstrate the presence of autoreactive serum IgE antibodies correlating with the severity of the disease. OBJECTIVE: Although several IgE-binding self-antigens have been reported, the whole repertoire of IgE-binding self-antigens is unknown. We aimed to estimate the repertoire size of autoreactive proteins related to AE and clone, produce, and characterize humoral and T-cell responses against novel self-antigens. METHODS: Phage surface-displayed human cDNA libraries were enriched for clones binding to serum IgE from patients with AE and screened by using high-throughput technology. Selected clones were used to produce the encoded proteins, to test their IgE-binding ability in Western blots and ELISAs, and their ability to induce mediator release from basophils of sensitized individuals. RESULTS: One hundred forty sequences encoding potential IgE-binding self-antigens associated with AE were identified. Sixteen sequences encoded already described self-antigens. Three new sequences showed homology with environmental allergens, 86 encoded known human proteins, 7 predicted proteins, and 28 showed sequence identity with genomic contigs. Immunoblotting and ELISA experiments demonstrated the presence of IgE antibodies in sera from patients with AE to 5 selected recombinant self-antigens and their ability to induce mediator release from basophils of patients with AE who have self-antigen-specific IgE antibodies. CONCLUSION: These data demonstrate a broad spectrum of at least 140 IgE-binding self-antigens associated with AE. By binding IgE antibodies or activating specific T cells, they might promote, perpetuate, or both existing skin inflammation.


Assuntos
Reações Antígeno-Anticorpo , Autoantígenos/imunologia , Basófilos/imunologia , Dermatite Atópica/imunologia , Imunoglobulina E/imunologia , Adulto , Dermatite Atópica/sangue , Feminino , Biblioteca Gênica , Humanos , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Masculino , Proteínas Recombinantes/imunologia
19.
Int Arch Allergy Immunol ; 150(1): 59-65, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19339803

RESUMO

BACKGROUND: IgE-mediated allergy can be treated by subcutaneous allergen-specific immunotherapy (SIT). However, the percentage of allergic patients undergoing SIT is low, mainly due to the long duration of the therapy and the risk of severe systemic allergic reactions associated with the allergen administration. To improve the safety and attractiveness of SIT for patients, alternative routes of allergen administration are being explored, such as sub-lingual or oral administration. METHODS: The present study evaluated direct intralymphatic allergen administration as a means to enhance SIT with bee venom and cat fur allergens in mice. Allergen-specific antibody and T-cell responses were analysed by ELISA and flow cytometry. The therapeutic potential of intralymphatic immunisation in sensitised mice was analysed using an anaphylaxis model. RESULTS: Direct injection of the major bee venom allergen phospholipase A(2) or the major cat fur allergen Fel d 1 into inguinal lymph nodes enhanced allergen-specific IgG and T-cell responses when compared with subcutaneous injections. Moreover, only intralymphatic immunisation stimulated the production of the Th1-dependent subclass IgG2a, which is associated with improved protection against allergen-induced anaphylaxis. Biodistribution studies showed that injection into the lymph node delivered antigen more efficiently to subcutaneous lymph nodes than subcutaneous injection. CONCLUSIONS: As intralymphatic immunisation induced more than 10-fold higher IgG2a responses with 100-fold lower allergen doses than subcutaneous immunisation, this approach should allow to reduce both the number of allergen injections as well as the allergen dose, improving both efficacy and safety of SIT.


Assuntos
Alérgenos/administração & dosagem , Dessensibilização Imunológica/métodos , Hipersensibilidade/prevenção & controle , Alérgenos/imunologia , Animais , Venenos de Abelha/imunologia , Citocinas/biossíntese , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Glicoproteínas/imunologia , Imunoglobulina G/sangue , Injeções Intralinfáticas , Masculino , Camundongos , Fosfolipases A2/imunologia , Linfócitos T/imunologia
20.
Mol Immunol ; 46(7): 1360-73, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19162325

RESUMO

Subtilisin-like serine proteases make up one of the most important allergen-families regarding the number of individual allergens. Previously, fungal subtilisin-like serine proteases have been identified from Aspergillus-, Penicillium-, and Trichophyton-species having a prevalence of IgE-reactivity between 33% and 80%. Since IgE-cross-reactivity is a common phenomenon within fungal species we wanted to know whether this protein also represents an allergen in Cladosporium herbarum. Hence, a screening of a C. herbarum cDNA library was performed using the coding sequence of the Penicillium oxalicum vacuolar serine protease (Pen o 18) as hybridization probe, ending up with a full-length clone. Biochemical and immunological characterization of this clone revealed that C. herbarum vacuolar serine protease most likely is synthesized as a precursor with an N-terminal pro-enzyme sequence and represents a minor allergen (Cla h 9) with a prevalence of IgE-reactivity of 15.5%. Furthermore Cla h 9 specifically reacted with the two monoclonal antibodies FUM20 and PCM39, as do the vacuolar serine proteases from Aspergillus fumigatus and Penicillium species. Investigation of IgE-cross-reactivity between Cla h 9 and other fungal serine proteases revealed that cross-reactivity is higher between vacuolar than alkaline serine proteases. IgE-epitope mapping of Cla h 9 was done in order to test whether four Cla h 9-peptides having a high sequence homology to previously determined Pen ch 18-IgE-epitopes also harbour IgE-epitopes. Three-dimensional models of the vacuolar serine proteases from C. herbarum and Penicillium chrysogenum were generated for the three-dimensional localization of the Cla h 9- and Pen ch 18- IgE-reactive and -non-reactive peptides. Taken together a new C. herbarum allergen has been identified, which may be useful in a molecule-based approach of C. herbarum allergy-diagnosis and -therapy. Moreover, Cla h 9 represents a further member of the subtilisin-like serine protease allergen-family, which stresses the importance of these proteins with respect to fungal IgE-cross-reactivity.


Assuntos
Alérgenos/imunologia , Cladosporium/imunologia , Serina Endopeptidases/genética , Serina Endopeptidases/imunologia , Vacúolos/enzimologia , Alérgenos/genética , Alérgenos/isolamento & purificação , Sequência de Aminoácidos , Sequência de Bases , Cladosporium/enzimologia , Cladosporium/genética , Clonagem Molecular , Reações Cruzadas , Mapeamento de Epitopos , Proteínas Fúngicas/genética , Proteínas Fúngicas/imunologia , Proteínas Fúngicas/isolamento & purificação , Modelos Moleculares , Dados de Sequência Molecular , Análise de Sequência de Proteína , Homologia de Sequência de Aminoácidos , Serina Endopeptidases/isolamento & purificação , Serina Endopeptidases/metabolismo , Vacúolos/metabolismo
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