Physical Exercise Induces Immunoregulation of TREG, M2, and pDCs in a Lung Allergic Inflammation Model.

The benefits of moderate aerobic physical exercise for allergic asthma are well-known, particularly that of the anti-inflammatory effect that occurs by reducing Th2 responses and lung remodeling. However, the mechanisms of this immunoregulation are still under investigation. In this study, we investigated the possible immunoregulatory mechanisms of lung inflammation induced by moderate aerobic exercise in an experimental asthma model. BALB/c mice were distributed into Control, Exercise (EX), OVA, and OEX groups. OVA and OEX groups were sensitized with ovalbumin (OVA) on days 0, 14, 21, 28, and 42 and were challenged with OVA aerosol three times a week from days 21 to 51. The EX and OEX groups underwent moderate aerobic physical exercise from days 21 to 51 (5 d/w, 1 h/d). The mice were euthanized on day 52. We evaluated pulmonary cytokine production, serum immunoglobulin levels, and the inflammatory cell profile in lung and mediastinal lymph nodes. OVA mice showed increased expression of IL-4, IL-6, IL-10, and TGF-ß and decreased macrophage type 2 (M2) recruitment. Physical exercise did not affect the increased antibody production of IgG2a, IgG1, or IgE induced by OVA. Of note, physical exercise alone markedly increased production of anti-inflammatory cytokines such as IL-10 and TGF-ß. Physical exercise in OVA-mice also increased the recruitment of M2 in the lungs, as well as the influx and activation of regulatory T cells (Tregs) and CD4 and CD8 lymphocytes. In the draining lymph nodes, it was also observed that physical exercise increased the activation of CD4 T cells, regardless of the presence of OVA. Notably, physical exercise decreased common dendritic cells' (cDCs; pro-inflammatory) expression of co-stimulatory molecules such as CD80, CD86, and ICOSL in the draining lymph nodes, as well as increased ICOSL in plasmacytoid dendritic cells (pDCs; anti-inflammatory). Together, these findings show that physical exercise modulates pulmonary allergic inflammation by increasing Treg and M2 recruitment, as well as pDCs activation, which leads to an increase in anti-inflammatory cytokines and a decrease in pro-inflammatory cells and mediators.

The Plant Proteinase Inhibitor CrataBL Plays a Role in Controlling Asthma Response in Mice.

Background. CrataBL is a protein isolated from Crataeva tapia bark. It has been shown to exhibit several biological properties, including anti-inflammatory, analgesic, antitumor, and insecticidal activities. There are no studies evaluating the role of CrataBL in experimental asthma models. Aim. To evaluate the effects of CrataBL on lung mechanics, inflammation, remodeling, and oxidative stress activation of mice with allergic pulmonary inflammation. Materials and Methods. BALB/c mice (6-7 weeks old, 25-30g) were divided into four groups: nonsensitized and nontreated mice (C group, n=8); ovalbumin- (OVA-) sensitized and nontreated mice (OVA group, n=8); nonsensitized and CrataBL-treated mice (C+CR group, n=8); OVA-sensitized and CrataBL-treated mice (OVA+CR group, n=8). We evaluated hyperresponsiveness to methacholine, bronchoalveolar lavage fluid (BALF), pulmonary inflammation, extracellular matrix remodeling, and oxidative stress markers. Results. CrataBL treatment in OVA-sensitized mice (OVA+CR group) attenuated the following variables compared to OVA-sensitized mice without treatment (OVA group) (all p<0.05): (1) respiratory system resistance (Rrs) and elastance (Ers) after methacholine challenge; (2) total cells, macrophages, polymorphonuclear cells, and lymphocytes in BALF; (3) eosinophils and volume fraction of collagen and elastic fibers in the airway and alveolar wall according to histopathological and morphometry analysis; (4) IL-4-, IL-5-, IL-13-, IL-17-, IFN-γ-, MMP-9-, TIMP-1-, TGF-ß-, iNOS-, and NF-kB-positive cells and volume of 8-iso-PGF2α in airway and alveolar septa according to immunohistochemistry; and (5) IL-4, IL-5, and IFN-γ according to an ELISA. Conclusion. CrataBL contributes to the control of hyperresponsiveness, pulmonary inflammation, extracellular matrix remodeling, and oxidative stress responses in an animal model of chronic allergic pulmonary inflammation.

Cigarette Smoke Increases CD8α+ Dendritic Cells in an Ovalbumin-Induced Airway Inflammation.

Asthma is an allergic lung disease and, when associated to cigarette smoke exposition, some patients show controversial signs about lung function and other inflammatory mediators. Epidemiologic and experimental studies have shown both increasing and decreasing inflammation in lungs of subjects with asthma and exposed to cigarette smoke. Therefore, in this study, we analyzed how cigarette smoke affects pro-inflammatory and anti-inflammatory mediators in a murine model of allergic pulmonary inflammation. We sensitized Balb/c mice to ovalbumin (OVA) with two intraperitoneal injections. After sensitization, the animals were exposed to cigarette smoke twice a day, 30 min per exposition, for 12 consecutive days. In order to drive the cell to the lungs, four aerosol challenges were performed every 48 h with the same allergen of sensitization. OVA sensitization and challenge developed pulmonary Th2 characteristic response with increased airway responsiveness, remodeling, increased levels of IgE, interleukin (IL)-4, and IL-13. Cigarette smoke, unexpectedly, reduced the levels of IL-4 and IL-13 and simultaneously decreased anti-inflammatory cytokines as IL-10 and transforming growth factor (TGF)-ß in sensitized and challenged animals. OVA combined with cigarette smoke exposition decreased the number of eosinophils in bronchoalveolar lavage and increased the number of neutrophils in lung. The combination of cigarette smoke and lung allergy increased recruitment of lymphoid dendritic cells (DCs) into lymph nodes, which may be the leading cause to an increase in number and activation of CD8+ T cells in lungs. In addition, lung allergy and cigarette smoke exposure decreased an important regulatory subtype of DC such as plasmacytoid DC as well as its activation by expression of CD86, PDL2, and ICOSL, and it was sufficient to decrease T regs influx and anti-inflammatory cytokines release such as IL-10 and TGF-ß but not enough to diminish the structural changes. In conclusion, we observed, in this model, that OVA sensitization and challenge combined with cigarette smoke exposure leads to mischaracterization of the Th2 response of asthma by decreasing the number of eosinophils, IL-4, and IL-13 and increasing number of neutrophils, which is related to the increased number of CD8ɑ+ DCs and CD8+ T cells as well as reduction of the regulatory cells and its released cytokines.

Vacina de Bordetella pertussis reduz IgE específica, inflamação e remodelamento num modelo animal de alergia respiratória induzida por ácaro / Bordetella pertussis vaccine reduces specific IgE, inflammation, and remodeling in an animal model of respiratory allergy caused by house dust mites

Objetivo: Adjuvantes, como lipopolissacárides bacterianos, vêm sendo estudados para melhorar a eficácia da imunoterapia alérgeno-específica. A vacina de Bordetella pertussis (Pw) mostrou ter papel protetor em modelos de asma induzida por ovalbumina. Porém, seu papel na alergia a ácaros é desconhecido. Avaliamos os efeitos da vacina difteria-tétano-coqueluche (DTPw) em um modelo murino de alergia respiratória induzida por Dermatophagoides pteronyssinus (Derp). Métodos: Num protocolo de 30 dias, camundongos BALB/c foram imunizados por via subcutânea com salina ou Derp, isoladamente ou associados às vacinas de difteria-tétano (DT) ou DTPw (dias 0, 7 e 14). Posteriormente, os animais sofreram desafio intranasal diariamente com salina ou Derp (dias 22 a 28) e foram sacrificados (dia 29). Avaliamos imunoglobulinas séricas específicas, celularidade no lavado bronco-alveolar (BAL), remodelamento das vias aéreas inferiores, densidade de leucócitos polimorfonucleares (PMN) e área de muco ácido no epitélio nasal. Resultados: Os animais sensibilizados com Derp produziram altos níveis de imunoglobulinas específicas, apresentaram aumento da densidade de PMN e da área de muco ácido nasal, elevação da celularidade no BAL e remodelamento. As vacinas levaram à redução dos níveis de IgE, sendo o grupo Derp-DTPw similar aos grupos salina. Os grupos vacinados tiveram redução da celularidade no BAL e do remodelamento, com resultados mais expressivos no grupo Derp-DTPw em relação ao Derp-DT. As vacinas DT e DTPw inibiram o infiltrado PMN nasal e DTPw modulou a produção do muco ácido. Conclusões: A vacina DTPw diminuiu a IgE específica sérica, inflamação nasal e pulmonar e o remodelamento das vias respiratórias inferiores.

Objective: Adjuvant therapies, such as the use of bacterial lipopolysaccharides, have been evaluated as tools to improve the effectiveness of allergen-specific immunotherapy. Bordetella pertussis vaccine (Pw) has been shown to have a protective role in asthma models induced by ovalbumin. Conversely, its role in allergy to dust mites is unknown. We evaluated the effects of diphtheria-tetanus-pertussis vaccine (DTPw) in a murine model of respiratory allergy induced by Dermatophagoides pteronyssinus (Derp). Methods: Over a 30-day protocol, BALB/c mice were immunized subcutaneously with saline or Derp, alone or combined with diphtheria-tetanus vaccine (DT) or DTPw (days 0, 7, and 14). Then, they were subjected to intranasal challenge with saline or Derp daily (days 22 to 28), and sacrificed on day 29. We evaluated serum specific immunoglobulins, bronchoalveolar lavage (BAL) cellularity, lower airway remodeling, density of polymorphonuclear leukocytes (PMN), and acidic mucus area in the nasal epithelium. Results: Animals sensitized to Derp produced high levels of specific immunoglobulins, showed increased PMN density and acidic mucus in the nasal mucosa, and elevated BAL cellularity and remodeling. Vaccines led to the reduction of IgE levels, with the Derp-DTPw group showing similar results to those of the saline groups. Vaccinated groups showed reduced BAL cellularity and airway remodeling, with more expressive results in the Derp-DTPw group compared to Derp-DT. DT and DTPw vaccines inhibited PMN infiltration in nasal mucosa, and DTPw modulated the production of acidic nasal mucus. Conclusions: DTPw vaccine decreased serum specific IgE, nasal and pulmonary inflammation, and lower airway remodeling.

Sensitization by subcutaneous route is superior to intraperitoneal route in induction of asthma by house dust mite in a murine mode / Sensibilização por via subcutânea é superior à intraperitoneal na indução de asma por ácaro em modelo murino

ABSTRACT Objective To develop a new experimental model of chronic allergic pulmonary disease induced by house dust mite, with marked production of specific immunoglobulin E (IgE), eosinophilic inflammatory infiltrate in the airways and remodeling, comparing two different routes of sensitization. Methods The protocol lasted 30 days. BALB/c mice were divided into six groups and were sensitized subcutaneously or intraperitoneally with saline (negative control), Dermatophagoides pteronyssinus (Der p) 50 or 500mcg in three injections. Subsequently they underwent intranasal challenge with Der p or saline for 7 days and were sacrificed 24 hours after the last challenge. We evaluated the titration of specific IgE anti-Der p, eosinophilic density in peribronchovascular space and airway remodeling. Results Both animals sensitized intraperitoneally and subcutaneously produced specific IgE anti-Der p. Peribronchovascular eosinophilia increased only in mice receiving lower doses of Der p. However, only the group sensitized with Der p 50mcg through subcutaneously route showed significant airway remodeling. Conclusion In this murine model of asthma, both pathways of sensitization led to the production of specific IgE and eosinophilia in the airways. However, only the subcutaneously route was able to induce remodeling. Furthermore, lower doses of Der p used in sensitization were better than higher ones, suggesting immune tolerance. Further studies are required to evaluate the efficacy of this model in the development of bronchial hyperresponsiveness, but it can already be replicated in experiments to create new therapeutic drugs or immunotherapeutic strategies.

RESUMO Objetivo Desenvolver um novo modelo experimental de doença pulmonar alérgica crônica por ácaro, com proeminente produção de imunoglobulina E (IgE) específica, infiltrado inflamatório eosinofílico nas vias aéreas e remodelamento, comparando duas vias diferentes de sensibilização. Métodos O protocolo teve duração de 30 dias. Camundongos BALB/c foram divididos em seis grupos submetidos à sensibilização por via subcutânea ou intraperitoneal com solução salina (controles negativos),Dermatophagoides pteronyssinus (Der p) 50 ou 500mcg, em três aplicações. Posteriormente, foram submetidos à provocação intranasal com Der p ou salina por 7 dias e sacrificados 24 horas após o último desafio. Avaliamos a titulação de IgE específica anti-Der p, densidade eosinofílica no espaço peribroncovascular e remodelamento das vias aéreas. Resultados Tanto os animais sensibilizados por via subcutânea como intraperitoneal produziram IgE específica anti-Der p. Ocorreu aumento da eosinofilia peribroncovascular apenas nos animais que receberam menor dose de Der p. Porém apenas o grupo sensibilizado com Der p 50mcg subcutânea apresentou remodelamento significativo das vias aéreas. Conclusão Neste modelo murino de asma, as duas vias de sensibilização levaram à produção de IgE específica e eosinofilia nas vias aéreas. No entanto, apenas a via subcutânea foi capaz de induzir ao remodelamento. Além disso, doses menores de Der p utilizadas foram superiores às mais elevadas, sugerindo tolerância. Mais estudos são necessários para avaliar a eficácia deste modelo no desenvolvimento da hiperresponsividade brônquica, mas ele pode ser replicado em experimentos para criação de novas estratégias terapêuticas medicamentosas ou imunoterápicas.