Upper and lower airways are considered a unified morphological and functional unit, and the connection existing between them has been observed for many years, both in health and in disease. There is strong epidemiologic, pathophysiologic, and clinical evidence supporting an integrated view of rhinitis and asthma: united airway disease in the present review. The term "united airway disease" is opportune, because rhinitis and asthma are chronic inflammatory diseases of the upper and lower airways, which can be induced by allergic or nonallergic reproducible mechanisms, and present several phenotypes. Management of rhinitis and asthma must be jointly carried out, leading to better control of both diseases, and the lessons of the Allergic Rhinitis and Its Impact on Asthma initiative cannot be forgotten.

Background: The benefits of aerobic training for the main features of asthma, such as bronchial hyperresponsiveness (BHR) and inflammation, are poorly understood. We investigated the effects of aerobic training on BHR (primary outcome), serum inflammatory cytokines (secondary outcome), clinical control and asthma quality of life (Asthma Quality of Life Questionnaire (AQLQ)) (tertiary outcomes).Methods: Fifty-eight patients were randomly assigned to either the control group (CG) or the aerobic training group (TG). Patients in the CG (educational programme+breathing exercises (sham)) and the TG (same as the CG+aerobic training) were followed for 3 months. BHR, serum cytokine, clinical control, AQLQ, induced sputum and fractional exhaled nitric oxide (FeNO) were evaluated before and after the intervention.Results: After 12 weeks, 43 patients (21 CG/22 TG) completed the study and were analysed. The TG improved in BHR by 1 doubling dose (dd) (95% CI 0.3 to 1.7 dd), and they experienced reduced interleukin 6 (IL-6) and monocyte chemoattractant protein 1 (MCP-1) and improved AQLQ and asthma exacerbation (p0.05). A within-group difference was found in the ACQ-6 for patients with non-well-controlled asthma and in sputum eosinophil and FeNO in patients in the TG who had worse airway inflammation.Conclusions: Aerobic training reduced BHR and serum proinflammatory cytokines and improved quality of life and asthma exacerbation in patients with moderate or severe asthma. These results suggest that adding exercise as an adjunct therapy to pharmacological treatment could improve the main features of asthma.Trial registration number: NCT02033122.

Clinical studies in asthma are not able to clear up all aspects of disease pathophysiology. Animal models have been developed to better understand these mechanisms and to evaluate both safety and efficacy of therapies before starting clinical trials. Several species of animals have been used in experimental models of asthma, such as Drosophila, rats, guinea pigs, cats, dogs, pigs, primates and equines. However, the most common species studied in the last two decades is mice, particularly BALB/c. Animal models of asthma try to mimic the pathophysiology of human disease. They classically include two phases: sensitization and challenge. Sensitization is traditionally performed by intraperitoneal and subcutaneous routes, but intranasal instillation of allergens has been increasingly used because human asthma is induced by inhalation of allergens. Challenges with allergens are performed through aerosol, intranasal or intratracheal instillation. However, few studies have compared different routes of sensitization and challenge. The causative allergen is another important issue in developing a good animal model. Despite being more traditional and leading to intense inflammation, ovalbumin has been replaced by aeroallergens, such as house dust mites, to use the allergens that cause human disease. Finally, researchers should define outcomes to be evaluated, such as serum-specific antibodies, airway hyperresponsiveness, inflammation and remodeling. The present review analyzes the animal models of asthma, assessing differences between species, allergens and routes of allergen administration.

Heart tissue destruction in chronic Chagas' disease cardiomyopathy (CCC) may be caused by autoimmune recognition of heart tissue by a mononuclear cell infiltrate decades after Trypanosoma cruzi infection. Indirect evidence suggests there is molecular mimicry between T. cruzi and heart tissue. In murine models of CCC, antibodies and CD4+ T cells recognize myosin, the major heart protein. We recently identified a heart-specific epitope of cardiac myosin heavy chain (residues 1442-1447, AAALDK) that is crossreactive with a homologous sequence (AAAGDK) of the immunodominant T. cruzi antigen B13. Furthermore, cardiac myosin-B13 crossreactive antibodies are present in 100% CCC patients vs 14% asymptomatic T. cruzi-seropositive individuals (P = 2.3 x 10(-6)), suggesting a role for molecular mimicry between cardiac myosin and B13 in CCC pathogenesis. In this paper, we obtained heart-infiltrating T cell clones from CCC patients to assess whether molecular mimicry between cardiac myosin and B13 is directly involved in the genesis of heart lesions. We identified T cell clones derived from CCC heart lesions simultaneously responsive to cardiac myosin heavy chain (but not skeletal myosin heavy chain) and B13 T. cruzi protein, but could not find T cell clones primarily reactive to any T. cruzi antigen. Together with the association of myosin-B13 crossreactive antibodies with CCC, the present data strongly suggest the relevance of molecular mimicry between cardiac myosin and the T. cruzi protein B13 in the pathogenesis of heart lesions in chronic Chagas' disease cardiomyopathy.

Background β-Hemolytic streptococcal infection in developing countries still causes thousands of cases of rheumatic heart disease, demanding surgical valve correction. Antigenic mimicry between self and streptococcal components has been proposed as the triggering factor leading to autoimmunity in individuals with genetic susceptibility. Although heart streptococcal–M protein cross-reactive antibodies have been demonstrated, heart tissue damage seems to be T lymphocyte–dependent. We studied the infiltrating T lymphocytes in rheumatic heart lesions with the aim of understanding the role of cellular immune response at the site of the lesions. Methods and Results We obtained 107 T-cell clones from surgical fragments of cardiac tissue from four rheumatic heart disease patients. We tested their capacity to recognize streptococcal M protein–derived synthetic peptides and heart proteins. We found eight infiltrating T-cell clones from all four patients that simultaneously recognize streptococcal M and heart proteins. Among the M-protein sequences tested, only synthetic peptides corresponding to regions 1 through 25, 81 through 103, and 163 through 177 were simultaneously recognized with heart protein fractions. Interestingly, regions 81 through 103 and 163 through 177 have been known to bear heart cross-reactive epitopes at the antibody level. Five of these clones are CD4 ⁺ , and one is CD8 ⁺ . Conclusions The presence of heart–M protein cross-reactive T-cell clones in rheumatic heart lesions suggests their direct involvement in the pathogenesis of this disease. The dissection of protective and pathogenic epitopes of streptococcal M protein is an important step in allowing the development of a safe anti-streptococcal synthetic vaccine.