Adaptive Immune Response to Mycobacterium abscessus Complex (MABSC) in Cystic Fibrosis and the Implications of Cross-Reactivity.

Background: We aimed to characterise the adaptive immune response to Mycobacterium abscessus complex (MABSC) and its cross-reactivity with Mycobacterium avium complex (MAC) and Mycobacterium bovis (Bacille Calmette-Guérin, BCG) in cystic fibrosis (CF) patients and non-CF controls in terms of lymphocyte proliferation and immunophenotyping, cytokine production and anti-MABSC IgG plasma levels. Methods: In this cross-sectional analysis, peripheral blood mononuclear cells (PBMC) from CF patients with MABSC (CF/MABSC, n=12), MAC infection history (CF/MAC, n=5), no NTM history (CF/NTM-, n=15), BCG-vaccinated (C/BCG+, n=9) and non-vaccinated controls (C/BCG-, n=8) were cultured for four days under stimulation with an in-house MABSC lysate and we used flow cytometry to assess lymphocyte proliferation (given by lymphoblast formation) and immunophenotypes. Cytokine production was assessed after overnight whole blood stimulation with the same lysate, and anti-MABSC IgG levels were measured in plasma from non-stimulated blood. Results: All CF/MABSC patients had increased CD3+ and CD19+ lymphoblast formation upon PBMC stimulation with MABSC lysate. There was a higher rate of CD3+ than CD19+ lymphoblasts, predominance of CD4+ over CD8+ lymphoblasts, IFN-γ, TNF-α and IL-2 production, low production of the Th17-associated IL-17, and discrete or no production of Th2/B cell-associated cytokines soluble CD40 ligand (CD40L), IL-4 and IL-5, indicating a Th1-dominated phenotype and infection restricted to the lungs. A similar pattern was seen in C/BCG+ controls, and CF/MAC patients, pointing to cross-reactivity. MABSC-IgG levels were higher in CF/MABSC patients than in both control groups, but not CF/NTM- patients, most of whom also had CD3+ and/or CD19+ lymphoblast formation upon PBMC stimulation, indicating previous exposure, subclinical or latent infection with MABSC or other NTM. Conclusion: The anti-MABSC immune response is Th1-skewed and underlines the cross-reactivity in the anti-mycobacterial immune response. The results, together with published clinical observations, indicate that BCG vaccination may cross-react against NTM in CF patients, and this should be investigated. Due to cross-reactivity, it would also be interesting to investigate whether a combination of MABSC-induced cytokine production by blood cells and anti-MABSC IgG measurement can be useful for identifying latent or subclinical infection both with MABSC and other NTM in CF patients.

Effective combined antiretroviral therapy provides partial immune recovery to mycobacterial antigens in vertically infected, BCG-vaccinated youth living with HIV.

BACKGROUND: We assessed the cytokine response by PBMC of youth living with HIV (YLHIV) under combined antiretroviral therapy (cART) to Mycobacterium tuberculosis (Mtb) and Mycobacterium bovis (BCG) antigens. METHODS: PBMC from 20 Brazilian YLHIV under cART with long-term (≥1 year) virological control, and 20 healthy controls were cultured for 24-96 h under stimulation with BCG, Mtb lysates, ESAT-6 and SEB. We measured TNF-α, IFN-γ, IL-2, IL-4, IL-5, IL-10 and IL-17 in culture supernatants using a cytometric bead array. RESULTS: Controls had higher IFN-γ production at 24, 48, 72 and 96 h upon stimulation with BCG lysate, plateauing at 48 h (Median = 1991 vs. 733 pg/mL; p = 0.01), and after 48-72 h of stimulation with Mtb lysate, plateauing at 48 h (3838 vs. 2069 pg/mL; p = 0.049). YLHIV had higher TNF-α production at all time points upon stimulation with ESAT-6, with highest concentration at 36 h (388 vs. 145 pg/mL; p = 0.02). Within the YLHIV group, total CD4 T cell count and CD4/CD8 ratio were associated with IFN-γ response to Mtb lysate and ESAT-6, respectively. CONCLUSIONS: Even under long-term cART, YLHIV seem to have a suboptimal T-helper-1 response to mycobacterial antigens. This can be explained by early immunodeficiency in vertical infection, with lasting damage.

Frequency of respiratory pathogens other than SARS-CoV-2 detected during COVID-19 testing.

The frequencies of 19 respiratory pathogens other than SARS-CoV-2 were assessed in 6,"?>235 Brazilian individuals tested for COVID-19. Overall, only 83 individuals who tested positive for SARS-CoV-2 had codetection of other pathogens. Individuals infected with Rhinovirus/Enterovirus, Human Coronavirus (HCoV)-HKU1, HCoV-NL63, HPIV-4, Influenza A (-H1N1 and other subtypes), Influenza B, Human Respiratory Syncytial Virus and Human Metapneumovirus were less likely to test positive for SARS-CoV-2. Infection with Streptococcys pyogenes, Chlamydophila pneumoniae, Mycoplasma pneumoniae, and Bordetella pertussis were more frequent in individuals who tested negative for SARS-CoV-2, but without significancy. We found 150 individuals infected with ≥2 pathogens other than SARS-CoV-2, only 3 out of whom tested positive for COVID-19. The codetection frequency was low in individuals diagnosed with COVID-19. Other viral infections may provide a cross-reactive, protective immune response against SARS-CoV-2. Screening for bacterial respiratory infections upon COVID-19 testing is important to drive suitable therapeutic approaches and avoid unnecessary antibiotic prescription.

One Year of Coronavirus Disease 2019 (COVID-19) in Brazil: A Political and Social Overview.

Background: Coronavirus Disease 2019 (COVID-19) became the deadliest pandemic of the new millennium. One year after it became a pandemic, the current COVID-19 situation in Brazil is an example of how the impacts of a pandemic are beyond health outcomes and how health, social, and political actions are intertwined. Objectives: We aimed to provide an overview of the first year of the COVID-19 pandemic in Brazil, from a social and political point of view, and to discuss the perspectives from now on. Methods: This is a narrative review using official, scientific (PubMed, Medline, and SciELO databases) and publicly available data. Press articles were also used that contain important information not found in these databases. Findings: We address the impacts of COVID-19 in different regions of Brazil, on indigenous populations, health care workers, and how internal social contrasts impacted the pandemics advance across the country. We also discuss key points that culminated in the countrys failed management of the COVID-19 spread, such as poor management of the public health care system, disparities between public and private health care infrastructure, lack of mass testing and viral spread tracking, lack of preparedness and planning to implement strict isolation and social distancing measures, and, most importantly, political instability, a deteriorating Health Ministry and sabotaging attitudes of the countrys president, including anti-scientific actions, underplaying COVID-19 severity, spreading and powering fake news about the pandemic, promoting knowingly inefficient medications for COVID-19 treatment, and interference in collective health policies, including the countrys vaccination plan. Conclusions: After one year of COVID-19 and a disastrous management of the disease, Brazil has more than 11 million cases, 270,000 deaths, and the highest number of daily deaths due to COVID-19 in the world, most of which could have been avoided and can be credited to negligence of municipal, state, and federal authorities, especially President Jair Messias Bolsonaro. Unfortunately, the country is an example of what not to do in a pandemic setting. Key Points: One year after COVID-19 was declared a pandemic, Brazil had the second higher number of cases and deaths, and the highest number of daily deaths due to the disease. Lack of massive testing, non-stringent and ineffective collective health policies, poor management of the public health care system, and political instability were the main drivers of the countrys flawed management of the COVID-19 advancement. Anti-science and sabotaging actions by government had a pivotal role in the countrys current situation. Brazil has a large territory and is marked by social contrasts among different regions and states, which showed contrasting data regarding the impact caused by COVID-19. COVID-19 databases and data sharing are important to provide an overview of epidemiological aspects of the disease; however, Brazil lacks standardization in these datasets.

Safety, Tolerability, and Effects of Sodium Bicarbonate Inhalation in Cystic Fibrosis.

BACKGROUND: Among the many consequences of loss of CFTR protein function, a significant reduction of the secretion of bicarbonate (HCO3-) in cystic fibrosis (CF) is a major pathogenic feature. Loss of HCO3- leads to abnormally low pH and impaired mucus clearance in airways and other exocrine organs, which suggests that NaHCO3 inhalation may be a low-cost, easily accessible therapy for CF. OBJECTIVE: To evaluate the safety, tolerability, and effects of inhaled aerosols of NaHCO3 solutions (4.2% and 8.4%). METHODS: An experimental, prospective, open-label, pilot, clinical study was conducted with 12 CF volunteer participants over 18 years of age with bronchiectasis and pulmonary functions classified as mildly to severely depressed. Sputum rheology, pH, and microbiology were examined as well as spirometry, exercise performance, quality-of-life assessments, dyspnea, blood count, and venous blood gas levels. RESULTS: Sputum pH increased immediately after inhalation of NaHCO3 at each clinical visit and was inversely correlated with rheology when all parameters were evaluated: [G' (elasticity of the mucus) = - 0.241; G″ (viscosity of the mucus) = - 0.287; G* (viscoelasticity of the mucus) = - 0.275]. G* and G' were slightly correlated with peak flow, forced expiratory volume in 1 s (FEV1), and quality of life; G″ was correlated with quality of life; sputum pH was correlated with oxygen consumption (VO2) and vitality score in quality of life. No changes were observed in blood count, venous blood gas, respiratory rate, heart rate, peripheral oxygen saturation of hemoglobin (SpO2), body temperature, or incidence of dyspnea. No adverse events associated with the study were observed. CONCLUSION: Nebulized NaHCO3 inhalation appears to be a safe and well tolerated potential therapeutic agent in the management of CF. Nebulized NaHCO3 inhalation temporarily elevates airway liquid pH and reduces sputum viscosity and viscoelasticity.

Secretory IgA-mediated immune response in saliva and early detection of Pseudomonas aeruginosa in the lower airways of pediatric cystic fibrosis patients.

Pseudomonas aeruginosa (Pa) detection in the paranasal sinuses may help to prevent or postpone bacterial aspiration to the lower airways (LAW) and chronic lung infection in cystic fibrosis (CF). We assessed the ability of an ELISA test for measurement of specific Pa secretory IgA (sIgA) in saliva (a potential marker of sinus colonization) to early detect changes in the Pa LAW status (indicated by microbiological sputum or cough swab culture and specific serum IgG levels) of 65 patients for three years, in different investigation scenarios. Increased sIgA levels were detected in saliva up to 22 months before changes in culture/serology. Patients who remained Pa-positive had significantly increased sIgA levels than patients who remained Pa-negative, both at the baseline (39.6 U/mL vs. 19.2 U/mL; p = 0.02) and at the end of the follow-up (119.4 U/mL vs. 25.2 U/mL; p < 0.001). No association was found between sIgA levels in saliva and emergence or recurrence of Pa in the LAW. A positive median sIgA result in the first year of follow-up implied up to 12.5-fold increased risk of subsequent Pa exposure in the LAW. Our test detected early changes in the P. aeruginosa LAW status and risk of exposure to P. aeruginosa in the LAW with two years in advance. Comparison with sinus culture is needed to assess the test's ability to identify CF patients in need of a sinus approach for Pa investigation, which could provide opportunities of Pa eradication before its aspiration to the lungs.

IgG avidity to Pseudomonas aeruginosa over the course of chronic lung biofilm infection in cystic fibrosis.

BACKGROUND AND OBJECTIVES: The mechanisms leading to low effectiveness of the humoral immune response against P. aeruginosa in cystic fibrosis (CF) are poorly understood. The aim of the present study was to assess the avidity maturation of specific antipseudomonal IgG before and during the development of chronic lung infection in a cohort of Danish CF patients. METHODS: Avidity maturation was assessed against a pooled P. aeruginosa antigen (St-Ag) and against P. aeruginosa alginate in 10 CF patients who developed chronic lung infection and 10 patients who developed intermittent lung colonization, using an ELISA technique with the thiocyanate elution method. Avidity was quantitatively determined by calculating the avidity Constant (Kav). RESULTS: IgG avidity to St-Ag significantly increased at the onset (Median Kav=2.47) and one year after the onset of chronic infection (Median Kav=3.27), but did not significantly changed in patients who developed intermittent colonization. IgG avidity against alginate did not significantly change over the years neither in patients who developed chronic lung infection (Median Kav=3.84 at the onset of chronic infection), nor in patients who developed intermittent colonization. CONCLUSION: IgG avidity to P. aeruginosa alginate does not significantly enhance as chronic lung infection progresses. This probably plays a role in the difficulty to mount an effective opsonophagocytic killing to clear mucoid P. aeruginosa infection in CF.

Mechanisms of humoral immune response against Pseudomonas aeruginosa biofilm infection in cystic fibrosis.

P. aeruginosa chronic lung infection is the major cause of morbidity and mortality in patients with cystic fibrosis (CF), and is characterized by a biofilm mode of growth, increased levels of specific IgG antibodies and immune complex formation. However, despite being designed to combat this infection, such elevated humoral response is not associated with clinical improvement, pointing to a lack of anti-pseudomonas effectiveness. The mode of action of specific antibodies, as well as their structural features, and even the background involving B-cell production, stimulation and differentiation into antibody-producing cells in the CF airways are poorly understood. Thus, the aim of this review is to discuss studies that have addressed the intrinsic features of the humoral immune response and provide new insights regarding its insufficiency in the CF context.

Association of growth and nutritional parameters with pulmonary function in cystic fibrosis: a literature review / Associação dos parâmetros de crescimento e nutricionais com função pulmonar na fibrose cística: revisão da literatura

Abstract Objective: To review the literature addressing the relationship of growth and nutritional parameters with pulmonary function in pediatric patients with cystic fibrosis. Data source: A collection of articles published in the last 15 years in English, Portuguese and Spanish was made by research in electronic databases - PubMed, Cochrane, Medline, Lilacs and Scielo - using the keywords cystic fibrosis, growth, nutrition, pulmonary function in varied combinations. Articles that addressed the long term association of growth and nutritional parameters, with an emphasis on growth, with pulmonary disease in cystic fibrosis, were included, and we excluded those that addressing only the relationship between nutritional parameters and cystic fibrosis and those in which the aim was to describe the disease. Data synthesis: Seven studies were included, with a total of 12,455 patients. Six studies reported relationship between growth parameters and lung function, including one study addressing the association of growth parameters, solely, with lung function, and all the seven studies reported relationship between nutritional parameters and lung function. Conclusions: The review suggests that the severity of the lung disease, determined by spirometry, is associated with body growth and nutritional status in cystic fibrosis. Thus, the intervention in these parameters can lead to the better prognosis and life expectancy for cystic fibrosis patients.

Resumo Objetivo: Revisar a literatura que aborda a relação entre os parâmetros de crescimento e nutricionais com a função pulmonar em pacientes pediátricos com fibrose cística. Fontes de dados: Dados foram coletados de artigos publicados nos últimos 15 anos em Inglês,Português e Espanhol através de pesquisa nas bases de dados eletrônicas - PubMed, Cochrane, Medline, Lilacs e Scielo - usando as palavras-chave: fibrose cística, crescimento, nutrição, função pulmonar utilizando combinações variadas. Os artigos que analisaram a associação de longo prazo entre parâmetros de crescimento e nutricionais, com ênfase em crescimento, com doença pulmonar em fibrose cística, foram incluídos, sendo excluídos aqueles que analisaram apenas a relação entre os parâmetros nutricionais e fibrose cística e aqueles em que o objetivo era descrever a doença. Síntese dos dados: Sete estudos foram incluídos, com um total de 12.455 pacientes. Seis relataram relação entre parâmetros de crescimento e função pulmonar, incluindo um estudo que analisou apenas a associação de parâmetros de crescimento com a função pulmonar, e todos os sete relataram associação entre parâmetros nutricionais e função pulmonar. Conclusões: A revisão sugere que a gravidade da doença pulmonar, determinada por espirometria, está associada com crescimento corporal e o estado nutricional em fibrose cística. Assim, a intervenção nesses parâmetros pode contribuir para um melhor prognóstico e expectativa de vida em pacientes com fibrose cística.

Association of growth and nutritional parameters with pulmonary function in cystic fibrosis: a literature review. / Associação dos parâmetros de crescimento e nutricionais com função pulmonar na fibrose cística: revisão da literatura.

OBJECTIVE: To review the literature addressing the relationship of growth and nutritional parameters with pulmonary function in pediatric patients with cystic fibrosis. DATA SOURCE: A collection of articles published in the last 15 years in English, Portuguese and Spanish was made by research in electronic databases - PubMed, Cochrane, Medline, Lilacs and Scielo - using the keywords cystic fibrosis, growth, nutrition, pulmonary function in varied combinations. Articles that addressed the long term association of growth and nutritional parameters, with an emphasis on growth, with pulmonary disease in cystic fibrosis, were included, and we excluded those that addressing only the relationship between nutritional parameters and cystic fibrosis and those in which the aim was to describe the disease. DATA SYNTHESIS: Seven studies were included, with a total of 12,455 patients. Six studies reported relationship between growth parameters and lung function, including one study addressing the association of growth parameters, solely, with lung function, and all the seven studies reported relationship between nutritional parameters and lung function. CONCLUSIONS: The review suggests that the severity of the lung disease, determined by spirometry, is associated with body growth and nutritional status in cystic fibrosis. Thus, the intervention in these parameters can lead to the better prognosis and life expectancy for cystic fibrosis patients.

Assessment of IgG antibodies to Pseudomonas aeruginosa in patients with cystic fibrosis by an enzyme-linked immunosorbent assay (ELISA).

BACKGROUND: The usefulness of serological tests for detection of P. aeruginosa pulmonary infection in cystic fibrosis (CF) is controversial. Here, we assessed the value of detecting anti-P. aeruginosa IgG by a quantitative enzyme-linked immunosorbent assay (ELISA) for identification of P. aeruginosa infection in patients with cystic fibrosis. METHODS: Serum concentrations of anti-P. aeruginosa IgG were assessed in 117 CF patients classified according to their P. aeruginosa colonization/infection status (never colonized; free of infection; intermittently colonized and chronically infected) and in 53 healthy subjects by the ELISA test standardized with the St-Ag:1-17 antigen. RESULTS: The rate of IgG seropositivity and the median of IgG concentrations of this antibody in patients chronically infected were significantly higher than those found in the other CF groups and in the healthy control group. CONCLUSION: Detection of anti-P. aeruginosa IgG can be an useful tool for identification of P. aeruginosa chronic infection in patients with CF. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_158.

Serum antibodies to Pseudomonas aeruginosa in cystic fibrosis as a diagnostic tool: a systematic review.

BACKGROUND: A systematic literature review of the last 40 years on the research of serum antibodies to Pseudomonas aeruginosa in cystic fibrosis and its utility as a diagnostic tool. METHODS: Research papers in English, Portuguese, and Spanish were accessed through electronic databases (PubMed, Medline, LILACS, and SciELO). RESULTS: 26 studies were assessed. ELISA technique was the most commonly used technique to detect serum P. aeruginosa antibodies. The most consistent results were those in which the response against the antigen St-Ag:1-17 was evaluated. The accuracy levels of the ELISA technique remain controversial, but most studies showed a good correlation between antibody titers and microbiological culture. CONCLUSIONS: The detection of serum antibodies to P. aeruginosa shows capacity for early detection of this pathogen and potential utility and viability of incorporation in the diagnostic routine of patients with cystic fibrosis.

The copper interference with the melanogenesis OF Cryptococcus neoformans.

Melanin is a pigment produced by laccase, a phenoloxydase enzyme, and is related to the virulence of Cryptococcus neoformans as it is also considered an adaption mechanism to environmental conditions and protection against UV radiation, phagocytic system attack and antifungal drugs. Laccase synthesis is stimulated by several factors, including copper metabolism. The current study shows C. neoformans strains with higher melanization intensity when grown in L-dopa medium supplemented with different concentrations of copper sulfate. This increase shows that melanization rates may be enhanced in the presence of copper ions and may also enhance the virulence of C. neoformans in infected patients that present increasing copper concentrations in serum, such as those with HIV. The virulence of these strains may also be increased in the environment, where this metal is available as CuSO4 in algicidal and fungicidal compounds.

THE COPPER INTERFERENCE WITH THE MELANOGENESIS OF Cryptococcus neoformans / A interferência de cobre na melanogênese de Cryptococcus neoformans

Melanin is a pigment produced by laccase, a phenoloxydase enzyme, and is related to the virulence of Cryptococcus neoformans as it is also considered an adaption mechanism to environmental conditions and protection against UV radiation, phagocytic system attack and antifungal drugs. Laccase synthesis is stimulated by several factors, including copper metabolism. The current study shows C. neoformans strains with higher melanization intensity when grown in L-dopa medium supplemented with different concentrations of copper sulfate. This increase shows that melanization rates may be enhanced in the presence of copper ions and may also enhance the virulence of C. neoformans in infected patients that present increasing copper concentrations in serum, such as those with HIV. The virulence of these strains may also be increased in the environment, where this metal is available as CuSO4 in algicidal and fungicidal compounds.

A melanina é um pigmento produzido pela enzima lacase, uma fenoloxidase, e está associada à virulência de Cryptococcus neoformans sendo considerada mecanismo de adaptação às condições ambientais e proteção contra a radiação UV, ataque do sistema fagocítico e antifúngicos. A lacase tem sua síntese estimulada por diversos fatores, incluindo o metabolismo de cobre. Este estudo mostra linhagens de C. neoformans com maior intensidade de melanização quando cultivadas em meio L-dopa suplementado com diferentes concentrações de sulfato de cobre. Este aumento demonstra que as taxas de melanização podem ser aumentadas na presença de íons cobre e também aumentar a virulência de C. neoformans em pacientes infectados que apresentam aumento nas concentrações séricas de íons cobre tais como pacientes com HIV. A virulência destas linhagens também pode ser incrementada no meio ambiente, onde este metal está disponível como CuSO4 em compostos algicidas e fungicidas.