Search

Background: Acquired deficiency of C1 inhibitor (AAE-C1-INH) is a very rare cause of recurrent angioedema, with few cases reported in the literature. We aimed to describe a series of patients with AAE-C1-INH who were diagnosed and received care at angioedema reference centers in Brazil, affiliated to the Brazilian Group of Studies on Hereditary Angioedema. Methods: Fourteen patients from 8 Brazilian Angioedema Reference Centers, diagnosed with AAE-C1-INH, were included in this study. Clinical data collected included sex, date of birth, date of onset of symptoms, date of diagnosis, plasma levels of antigenic and/or functional C1-INH, levels of C4 and C1q, location and treatment of angioedema attacks, long-term prophylaxis, associated diseases, and definitive treatment. Results: Fourteen patients were identified with AAE-C1-INH. Most patients (10/14; 71.4%) were female. The median age at onset of symptoms was 56.5 years (range, 14–74 years; interquartile range [IQR], 32–64 years), and median age at diagnosis was 58.0 years (range, 20–76 years; IQR, 38–65 years), with a median time until diagnosis of 2 years (range, 0–6 years; IQR, 1–3 years). The most common manifestations were cutaneous (face, eyelids, lips, trunk, hands, feet, and genitals). Most patient had low levels of C4 (13/14; 92.8%) and of antigenic C1-INH (8/14; 57.1%). Four had decreased functional activity of C1-INH (4/7; 57.1%) and C1q levels were low in 5 patients (5/12; 41.6%). Underlying diseases were identified in all 14 patients, with lymphoma of the splenic marginal zone and monoclonal gammopathy of undetermined significance being the most frequent. Nine patients (64.2%) needed long-term prophylactic treatment for recurrent angioedema and 5 patients (46.7%) required treatment for angioedema attacks. Most of them (12/14; 85.7%) had resolution of angioedema. Conclusion: Therapy of AAE-C1-INH aims to control symptoms; however, diagnosis and treatment of the underlying disease, when present, should be an important target and may lead to the resolution of angioedema in patients with AAE-C1-INH.

Coagulation activation is a prominent feature of severe acute respiratory syndrome coronavirus 2 (COVID-19) infection. Activation of the contact system and intrinsic pathway has increasingly been implicated in the prothrombotic state observed in both sterile and infectious inflammatory conditions. We therefore sought to assess activation of the contact system and intrinsic pathway in individuals with COVID-19 infection. Baseline plasma levels of protease:serpin complexes indicative of activation of the contact and intrinsic pathways were measured in samples from inpatients with COVID-19 and healthy individuals. Cleaved kininogen, a surrogate for bradykinin release, was measured by enzyme-linked immunosorbent assay, and extrinsic pathway activation was assessed by microvesicle tissue factor–mediated factor Xa (FXa; MVTF) generation. Samples were collected within 24 hours of COVID-19 diagnosis. Thirty patients with COVID-19 and 30 age- and sex-matched controls were enrolled. Contact system and intrinsic pathway activation in COVID-19 was demonstrated by increased plasma levels of FXIIa:C1 esterase inhibitor (C1), kallikrein:C1, FXIa:C1, FXIa:α1-antitrypsin, and FIXa:antithrombin (AT). MVTF levels were also increased in patients with COVID-19. Because FIXa:AT levels were associated with both contact/intrinsic pathway complexes and MVTF, activation of FIX likely occurs through both contact/intrinsic and extrinsic pathways. Among the protease:serpin complexes measured, FIXa:AT complexes were uniquely associated with clinical indices of disease severity, specifically total length of hospitalization, length of intensive care unit stay, and extent of lung computed tomography changes. We conclude that the contact/intrinsic pathway may contribute to the pathogenesis of the prothrombotic state in COVID-19. Larger prospective studies are required to confirm whether FIXa:AT complexes are a clinically useful biomarker of adverse clinical outcomes.

Hereditary angioedema is a genetic disease with autosomal dominant inheritance and, in most cases, caused by C1 inhibitor deficiency. Patients present with recurrent edema affecting sub-cutaneous and mucus membranes with variable onset and severity. More than 50% of patients may become symptomatic before 10 years of age. Family history can help with the diagnosis; however, approximately 25% of the cases are de novo mutations. Biochemical diagnosis should be delayed until after 1 year of age. Children were often excluded from advances in therapy for hereditary angioedema since most of the new medicines were tested in adults and thus excluded by the Food and Drug Administration (FDA) and other agencies for approval to be used in children. Treatment of attacks is available for the pediatric patient; however, barriers still exist for the use of long-term prophylaxis in young children.

Objetivos: A ativação da hemostasia é um elemento crítico da patogênese da Covid-19. Microvesículas (MVs) são partículas de bicamada lipídica liberadas de diferentes células e que medeiam a tromboinflamação. Ademais, MVs já se mostraram ser biomarcadores relevantes em outras doenças infecciosas, incluindo pneumonias virais. Dessa forma, os objetivos desse estudo foram quantificar as MVs circulantes originadas de plaquetas, células endoteliais e eritrócitos; avaliar sua atividade pró-coagulante dependente de fator tecidual (APC-FT) e explorar sua relação com marcadores hemostáticos e desfechos clínicos na Covid-19. Material e métodos: Amostras de pacientes com Covid-19 internados devido a necessidade de oxigenoterapia foram coletadas em até 24h do diagnóstico, como parte de um estudo clínico. As amostras usadas neste estudo foram obtidas antes de qualquer intervenção terapêutica. MVs foram extraídas de plasma livre de plaquetas por ultracentrifugação, quantificadas por citometria de fluxo e a APC-FT foi determinada por meio de ensaio coagulométrico de um estágio. Marcadores de ativação da hemostasia foram quantificados por métodos imunológicos ou funcionais conforme indicados. Resultados: Foram incluídos 30 pacientes e 30 indivíduos saudáveis pareados por idade e sexo. O tempo médio de internação (TI) foi de 2,9±9,8 dias, 12 pacientes (40%) necessitaram de cuidados intensivos (UTI) e 28/30 pacientes sobreviveram. As contagens totais de MVs de plaquetas e células endoteliais estavam aumentadas em pacientes comparado com controles, ao passo que entre as MVs com expressão de fator tecidual (FT), apenas as de origem endotelial estavam aumentadas. A APC-FT mostrou-se aumentada em pacientes quando comparado com controles (p = 0,0007). Não observamos associações significativas entre as contagens de MVs ou APC-FT com desfechos clínicos como tempo de internação e tempo de UTI. Em contraste, observamos correlações significativas envolvendo MVs e outros marcadores de ativação da hemostasia a saber tais como MVs (totais) derivadas de plaquetas com fibrinogênio, F VIII:C, FVW e uPAR solúvel, e MV (FT+) derivadas de células endotelial com FVIII:C e FVW. Discussão e conclusão: O entendimento dos mecanismos pelos quais a hemostasia é ativada na Covid-19 é fundamental para o desenvolvimento de estratégias terapêuticas mais eficazes contra esta e outras doenças infecciosas associadas a aumento de eventos tromboembólicos e imunotrombose. Nossos resultados mostram que a Covid-19 moderada e grave se associa a aumento da contagem de MVs, e que uma fração destas MVs se associa a ativação da hemostasia. Novos ensaios para avaliação funcional da APC-FT serão necessários para definir a associação destes parâmetros com desfechos de gravidade na Covid-19.

PurposeHereditary angioedema (HAE) is a rare genetic disease with hyperactivated contact and kallikrein-kinin systems leading to bradykinin (BK) release and edema. SARS-CoV-2 infection results in inflammatory exacerbation. C1 inhibitor (C1-INH) deficiency could aggravate clinical outcomes, with HAE patients at a greater risk of adverse outcomes of COVID-19, however, data are still limited. Our aim was to characterize the course and severity of COVID-19 in patients with HAE.MethodsLatin American HAE reference centers evaluated SARS-CoV-2 infection in this population. Patients with confirmed diagnosis of HAE with (HAE-C1-INH) or without C1-INH deficiency (HAE-nC1-INH) were included. HAE symptomatology and the course of COVID-19 were characterized with the application of a questionnaire. Results66 patients from 10 countries (HAE-C1-INH 80,3%; HAE-nC1-INH 19.6%) were reported with SARS-CoV-2 infection. Comorbidities were absent in 69.7% of the patients and obesity present in 12.1%. Attacks occurred in 45.5% of patients with HAE during SARS-CoV-2 infection. Long term prophylaxis was reported in 52% (34/66) of HAE patients. Complete cure was observed in 61 patients (92.4%), pulmonary sequelae in 4 and death in one HAE-C1-INH patient. The cause of death was septic shock secondary to bacterial pulmonary coinfection. Disease progression was not impacted by sex, therapy or type of HAE (p = 0.803). Conclusion Attacks occurred in almost half of HAE patients suggesting that SARS-CoV-2 infection is a trigger. HAE did not represent a risk factor for a worse outcome of COVID-19, even in use of androgens.

Angioedema attacks are common causes of emergency care, and due to the potential for severity, it is important that professionals who work in these services know their causes and management. The mechanisms involved in angioedema without urticaria may be histamine- or bradykinin-mediated. The most common causes of histamine-mediated angioedema are foods, medications, insect sting and idiopathic. When the mediator is bradykinin, the triggers are angiotensin-converting enzyme inhibitors and factors related to acquired angioedema with deficiency of C1-inhibitor or hereditary angioedema, which are less common, but very important because of the possibility of fatal outcome. Hereditary angioedema is a rare disease characterized by attacks of edema that affect the subcutaneous tissue and mucous membranes of various organs, manifesting mainly by angioedema and abdominal pain. This type of angioedema does not respond to the usual treatment with epinephrine, antihistamines and corticosteroids. Thus, if not identified and treated appropriately, these patients have an estimated risk of mortality from laryngeal edema of 25% to 40%. Hereditary angioedema treatment has changed dramatically in recent years with the development of new and efficient drugs for attack management: plasma-derived C1 inhibitor, recombinant human C1-inhibitor, bradykinin B2 receptor antagonist (icatibant), and the kallikrein inhibitor (ecallantide). In Brazil, plasma-derived C1 inhibitor and icatibant have already been approved for use. Proper management of these patients in the emergency department avoids unnecessary surgery and, especially, fatal outcomes.

Purpose: There is still scarce data on SARS-CoV-2 infection in patients with Inborn Errors of Immunity (IEI) and many questions. We aimed to describe the clinical outcome of SARS-CoV-2 infection in Brazilian IEI patients and to identify factors influencing the outcome of infection.Methods: We did a cross-sectional, multicenter study that included patients of any age affected by IEI and SARS-CoV-2 infection. The variables studied were sex, age, type of IEI, comorbidities (number and type), treatment in use for IEI, clinical manifestations and severity of SARS-CoV-2 infection. Results: 121 patients were included: 55.4% female, ages from six months to 74 yo (median age = 25.1 yo). Most patients had predominantly antibody deficiency (n=53). The infection presented mostly as asymptomatic (n=21) and mild (n=66), and one child had multisystem inflammatory syndrome (MIS-C). We could not observe sex related susceptibility and observed a weak correlation between age and severity of infection. The number of comorbidities was higher in severe cases, particularly bronchiectasis and cardiopathy. There were no severe cases in hereditary angioedema patients. Six patients aged 2 to 74 years died, three of them with antibody deficiency. Conclusion: The outcome was mild in most patients, but the Case Fatality Ratio was higher than in the general population. Patients with complement deficiencies had milder COVID-19. However, the type of IEI was not a determining factor for severity. The severity of SARS-CoV-2 infection seems to be more related to older age, higher number of comorbidities and type of comorbidities (bronchiectasis and cardiopathy).

Objetivos: a imunotrombose consiste no processo que envolve a ativação concomitante da imunidade inata, hemostasia e endotélio como parte da resposta a patógenos, e vem sendo colocada no centro da fisiopatologia da Covid-19. Um elemento menos explorado da imunotrombose é a ruptura da barreira endotelial (BE), que permite o acesso dos leucócitos aos tecidos inflamados. Entre os reguladores da integridade da BE destacam-se as vias que envolvem a angiopoietina (Ang) 1 e 2 e seu receptor Tie2, e a via do VEGF-A/VE-caderina (VEC). Além deste papel, foi recentemente demonstrado que a ativação da via Ang/Tie2 inibe a ativação endotelial e a expressão de fator tecidual, estabilizando o endotélio no estado quiescente. Neste estudo determinamos os níveis circulantes de mediadores da integridade da BE na Covid-19, e exploramos sua associação com a gravidade da doença, assim como com a ativação da hemostasia através de um painel abrangente de biomarcadores. Materiais e métodos: as amostras foram obtidas de 30 pacientes internados por Covid-19 devido à hipoxemia e achados tomográficos típicos, e recrutados para um estudo clínico (REBEC: U1111-1250-1843). As amostras foram coletadas em até 24h do diagnóstico, antes de qualquer intervenção terapêutica. Os níveis de reguladores da BE foram medidos por métodos imunológicos (Elisa ou multiplex), e o de biomarcadores da hemostasia por kits comerciais específicos. Um grupo de 30 indivíduos saudáveis pareados por idade e sexo foram utilizados como controle. Dados clínicos e laboratoriais foram obtidos dos prontuários digitais. Resultados: o tempo médio de internação foi de 12,9 ± 9,8 dias, e 12 pacientes (40%) necessitaram de UTI. O dímero D médio foi de 3.609 ± 14.440 ng/mL. Os níveis circulantes de todos reguladores da integridade da BE encontraram-se aumentados em pacientes, quando comparado com controles (Ang1: 463.2 ± 194.6 vs 237.4 ± 104.9 pg/mL, p < 0.0001; Ang2: 1.926 (1.275-3.134) vs 1.215 (9-1.444) pg/mL, p < 0.0001; Tie2: 10.753 ± 2.377 vs 8.603 ± 1.851 pg/mL, p < 0.0001 e VEGF-A: 94.7 (73.4-116.0) vs 45.9 (39.7-57.0), p < 0.0001. Além disso, os níveis de alguns destes reguladores se associaram significativamente a desfechos de relevância clínica, a saber: (i) extensão da lesão pulmonar na tomografia: Ang2 e VEGF-A; (ii) tempo de internação em UTI: VEGF-A. Interessantemente, observamos correlações consistentes e significativas entre os níveis de reguladores da BE a proteínas envolvidas na ativação da hemostasia (fibrinogênio, VWF: Ag, uPAR, PAI-1 e P-selectina). Discussão: o interesse no estudo de reguladores da integridade da BE na Covid-19 já se justifica pelo fato de a doença envolver tanto o comprometimento da barreira alvéolo-capilar quanto a ativação da angiogênese, como demonstrado por outros autores. Nossos resultados reforçam a relevância destas vias através da associação observada com desfechos clínicos. Além disso, os resultados mostram pela primeira vez uma associação entre mediadores da integridade da BE e um painel amplo de biomarcadores da ativação da hemostasia, sugerindo um crosstalk entre estas vias na Covid-19, como demonstrado recentemente no contexto da sepse. Conclusões: nossos resultados apontam que a via Ang/Tie2 deve ser considerada um alvo terapêutico atrativo na Covid-19, por representar um elemento central da imunotrombose nestes pacientes.

Background Common variable immunodeficiency is the most prevalent symptomatic primary immunodeficiency in adults. Affected patients fail to mount an appropriate humoral response against community acquired infectious diseases and recent reports have provided data supporting the increased susceptibility of these patients to severe SARS-CoV-2 infections. In this context, the infusion of COVID-19 convalescent plasma could represent an effective therapeutic strategy. Case presentation 25-year old woman diagnosed with common variable immunodeficiency in 2013, developed severe COVID-19 that rapidly progressed to pneumonia presenting with multiple bilateral lung opacities that were both central and peripheral and presented as ground-glass and consolidation types involving all lobes, bilaterally. As blood oxygen saturation decayed and lung abnormalities were not responsive to large spectrum antibiotics and corticosteroids, patient was placed on mechanical ventilation and compassionate-use of approved COVID-19 convalescent donor plasma was introduced. The patient presented a rapid response to the approach and mechanical ventilation could be interrupted 24 h after first dose of COVID-19 convalescent donor plasma. As a whole, the patient received four doses of 200 mL convalescent plasma during a period of 6 days. There was rapid improvement of clinical status, with interruption of supplemental oxygen therapy after 6 days and reduction of lung abnormalities as evidence by sequential computed tomography scans. Conclusions This is a single patient report that adds to other few reports on common variable immunodeficiency and agammaglobulinemia, suggesting that COVID-19 convalescent donor plasma could be a valuable therapeutic approach to treat patients affected by dysgammaglobulinemias and presenting severe COVID-19.

Background: Coronavirus disease 19 (COVID-19) can develop into a severe respiratory syndrome that results in up to 40% mortality. Acute lung inflammatory edema is a major pathological finding in autopsies explaining O2 diffusion failure and hypoxemia. Only dexamethasone has been shown to reduce mortality in severe cases, further supporting a role for inflammation in disease severity. SARS-CoV-2 enters cells employing angiotensin-converting enzyme 2 (ACE2) as a receptor, which is highly expressed in lung alveolar cells. ACE2 is one of the components of the cellular machinery that inactivates the potent inflammatory agent bradykinin, and SARS-CoV-2 infection could interfere with the catalytic activity of ACE2, leading to the accumulation of bradykinin. Methods: In this case control study, we tested two pharmacological inhibitors of the kinin–kallikrein system that are currently approved for the treatment of hereditary angioedema, icatibant, and inhibitor of C1 esterase/kallikrein, in a group of 30 patients with severe COVID-19. Results: Neither icatibant nor inhibitor of C1 esterase/kallikrein resulted in changes in time to clinical improvement. However, both compounds were safe and promoted the significant improvement of lung computed tomography scores and increased blood eosinophils, which are indicators of disease recovery. Conclusions: In this small cohort, we found evidence for safety and a beneficial role of pharmacological inhibition of the kinin–kallikrein system in two markers that indicate improved disease recovery.

Introduction: Hereditary angioedema (HAE) with C1 inhibitor (C1-INH) deficiency is a rare autosomal dominant disease. Although the first symptoms can appear in childhood, the diagnosis’s delay has a strong impact on the patient’s quality of life. We analyzed clinical and laboratory characteristics and the drug therapy of pediatric patients with HAE in Brazil. Methods: Medical records from 18 reference centers of HAE patients under 18 years of age were evaluated after confirmed diagnosis was performed by quantitative and/or functional C1-INH. Results: A total of 95 participants (51 M:44 F; mean age: 7 years old) out of 17 centers were included; 15 asymptomatic cases were identified through family history and genetic screening. Angioedema attacks affected the extremities (73.5%), gastrointestinal tract (57%), face (50%), lips (42.5%), eyelids (23.7%), genitals (23.7%), upper airways (10%), and tongue (6.3%). Family history was present in 84% of patients, and the mean delay in the diagnosis was 3.9 years. Long-term prophylaxis (51/80) was performed with tranexamic acid (39/80) and androgens (13/80); and short-term prophylaxis (9/80) was performed with tranexamic acid (6/80) and danazol (3/80). On-demand therapy (35/80) was prescribed: icatibant in 7/35, fresh frozen plasma in 16/35, C1-INH plasma-derived in 11/35, and tranexamic acid in 12/35 patients. Conclusions: This is the first study on HAE pediatric patients in Latin America. Clinical manifestations were similar to adults. Drugs such as androgens and tranexamic acid were indicated off-label, probably due to restricted access to specific drugs. Educational programs should address pediatricians to reduce late diagnosis and tailored child therapy.

Dear Editor,COVID-19 was first reported in December, 2019 in Wuhan, China, and rapidly spread across the globe 1. It has affected more than 6.4 million people and has led to the death of over 370 thousand as of June 2, 2020 (www.who.org). Severely affected patients present fever, dry cough, dyspnea, and fatigue, which are commonly associated with the development of pneumonia and acute respiratory distress syndrome (ARDS) 2. Advanced age, ischemic and congestive heart disease, hypertension, diabetes, and chronic obstructive pulmonary disease (COPD) are the most important independent predictors of death 2,3. As with other infectious diseases affecting the respiratory tract, asthma has been cited as a potential risk factor for severe COVID-194-6; however, no previous study has addressed this specific question.Here, we systematically reviewed all papers published on COVID-19 since its emergence in December 2019 to May 18, 2020, looking into the description of asthma as a premorbid condition and its putative association with severe progression of the disease.Two authors, NFM and CPJ, independently identified cross-sectional and longitudinal studies published before May 18, 2020, that reported on the prevalence of asthma as a premorbid condition of severe COVID-19 by systematically searching PubMed-NCBI database. We restricted the search for PubMed-NCBI because COVID-19 is a new medical condition and, currently, PubMed-NCBI covers more than 90% of MEDLINE providing a widely accessible biomedical resource 7. For database searches, language of the article was restricted to English. Search terms included the following: COVID-19 (COVID, COVID 19) ornCov or novel coronavirus or Sars-Cov-2 in the title and clinical characteristics or asthma anywhere in the text. Three authors, EM, EPA, and LAV, resolved eventual discrepancies by discussion and adjudication.We found 458 articles that met the initial inclusion search criteria (Supplementary Figure 1). All articles were assessed by authors and 290 were excluded (Supplementary Table 1) due to one or more of the following criteria: editorials; metanalyses; systematic reviews; commentaries; letters to the Editor; no description of patient’s clinical characteristics or premorbid conditions; and main text in a language other than English.The remaining 150 articles were included in the study. Supplementary Table 2 depicts the details of all articles analyzed. As a whole, the articles described the clinical aspects of 36,072 COVID-19 patients. One hundred and seven studies mentioned the existence of other respiratory premorbidities except for asthma. Asthma was mentioned as a premorbid condition in only eighteen studies (Table 1). There was a total of 8,690 patients included in the studies mentioning asthma, and 655 patients were previously diagnosed with asthma. In most of the studies describing other respiratory illnesses, COPD was the leading diagnosis.Based on the current medical records, we conclude that 7.5% of patients included in articles describing the clinical characteristics of COVID-19 patients and citing asthma were previously diagnosed with asthma. If all studies providing any clinical description of COVID-19 comorbidities are taken into consideration, asthma was present in only 1.8% of patients. These numbers are far less than expected considering the prevalence of asthma in the world. According to the World Asthma Report (http://www.globalasthmareport.org), there were as many as 339 million people living with asthma in the world in 2018, which corresponds to 4.4% of the world’s population.In conclusion, asthma does not seem to be an important premorbid condition in COVID-19 patients; or, conversely, it could be a protective factor, as previously proposed 8. The findings herein reported could be an epidemiological truth that should be further explored in mechanistic studies or could be due to the fact that researchers are not properly investigating and describing the premorbidities in COVID-19 patients. Whatever the reasons, the medical community should be aware of the implications of missing the diagnosis of a potentially severe respiratory disease such as asthma that could worsen the prognosis of COVID-19 patients.Acknowledgements. NFM was supported by The Sao Paulo Research Foundation (grant: 2016/17810-3), and CPJ was supported by Coordination for the Improvement of Higher Education Personnel (CAPES) grant: 1744875 and 88882.434715/2019-01. EM, LAV and EPA are supported by grants from Sao Paulo Research Foundation (grants: 2013/07607-8 and 2020/) and Brazilian National Council of Scientific and Technological Development (CNPq).Ethics. The study does not require ethical approval because the systematic review is based on published research and the original data are anonymous.

Background Primary angioedema (PA) is a complex disorder, presenting multiple hereditary (hereditary angioedema) and acquired subtypes (acquired angioedema). Despite a very similar clinical presentation among subtypes, the differential diagnosis is limited by the difficulty to identify bradykinin-mediated PA and the lack of specific biomarkers. Objectives To report the clinical and genetic features of Brazilian patients with PA. Methods Brazilian patients referred from 50 centers were diagnosed on the basis of clinical symptoms, C1 inhibitor (C1-INH) and C4 plasma measurements, and DNA sequencing of genes associated with hereditary angioedema. Results We characterized 92 patients with acquired angioedema and 425 with HAE: 125 with C1-INH deficiency, 180 with F12 mutations, and 120 of unknown cause. Thirty-one different mutations were identified in SERPING1 and 2 in F12, in addition to 2 mutations of uncertain significance in the ANGPT1 gene. The molecular diagnosis was decisive for 34 patients with HAE without family history, and for 39% of patients with inconsistent biochemical measurements. The median delay in diagnosis was 10 years, with a maximum of 18 years for HAE with C1-INH deficiency. Androgens and tranexamic acid were the most used drugs for long-term prophylaxis in all the PA subtypes, and they were used on demand by 15% of patients. Only 10% of patients reported the use of specific medication for HAE during attacks. Conclusions Our analysis exposes a broad picture of PA diagnosis and management in a developing country. Complement measurements presented considerable inconsistencies, increasing the diagnosis delay, while patients with PA with normal C1-INH remain with an inaccurate diagnosis and unspecific treatment.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the agent of a major global outbreak of respiratory tract disease known as coronavirus disease-2019 (COVID-19). SARS-CoV-2 infects mainly lungs and may cause several immune-related complications, such as lymphocytopenia and cytokine storm, which are associated with the severity of the disease and predict mortality1,2. The mechanism by which SARS-CoV-2 infection may result in immune system dysfunction is still not fully understood. Here we show that SARS-CoV-2 infects human CD4+T helper cells, but not CD8+T cells, and is present in blood and bronchoalveolar lavage T helper cells of severe COVID-19 patients. We demonstrated that SARS-CoV-2 spike glycoprotein (S) directly binds to the CD4 molecule, which in turn mediates the entry of SARS-CoV-2 in T helper cells. This leads to impaired CD4 T cell function and may cause cell death. SARS-CoV-2-infected T helper cells express higher levels of IL-10, which is associated with viral persistence and disease severity. Thus, CD4-mediated SARS-CoV-2 infection of T helper cells may contribute to a poor immune response in COVID-19 patients.

Made available in DSpace on 2020-12-12T02:25:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-09-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Fundo de Apoio ao Ensino, à Pesquisa e Extensão, Universidade Estadual de Campinas Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) COVID-19 can result in severe lung injury. It remained to be determined why diabetic individuals with uncontrolled glucose levels are more prone to develop the severe form of COVID-19. The molecular mechanism underlying SARS-CoV-2 infection and what determines the onset of the cytokine storm found in severe COVID-19 patients are unknown. Monocytes and macrophages are the most enriched immune cell types in the lungs of COVID-19 patients and appear to have a central role in the pathogenicity of the disease. These cells adapt their metabolism upon infection and become highly glycolytic, which facilitates SARS-CoV-2 replication. The infection triggers mitochondrial ROS production, which induces stabilization of hypoxia-inducible factor-1α (HIF-1α) and consequently promotes glycolysis. HIF-1α-induced changes in monocyte metabolism by SARS-CoV-2 infection directly inhibit T cell response and reduce epithelial cell survival. Targeting HIF-1ɑ may have great therapeutic potential for the development of novel drugs to treat COVID-19. Diabetic people with uncontrolled blood glucose levels have a greater risk to develop severe COVID-19 disease. Codo et al. show that elevated glucose levels and glycolysis promote SARS-CoV-2 (CoV-2) replication and cytokine production in monocytes through a mitochondrial ROS/hypoxia-inducible factor-1α dependent pathway, resulting in T cell dysfunction and epithelial cell death. Laboratory of Immunometabolism Department of Genetics Evolution Microbiology and Immunology Institute of Biology University of Campinas Department of Genetics Evolution Microbiology and Immunology Institute of Biology University of Campinas Department of Biochemistry and Tissue Biology Institute of Biology University of Campinas Department of Genetics at Ribeirao Preto Medical School University of Sao Paulo, Ribeirao Preto Department of Clinical and Toxicological analyses School of Pharmaceutical Sciences University of São Paulo Brazilian Biosciences National Laboratory (LNBio), Campinas Department of Animal Biology Institute of Biology University of Campinas, Campinas Department of Internal Medicine School of Medical Sciences University of Campinas, Campinas Department of Clinical Medicine School of Medical Sciences University of Campinas, Campinas Hematology and Hemotherapy Center University of Campinas, Campinas Obesity and Comorbidities Research Center (OCRC) University of Campinas Experimental Medicine Research Cluster (EMRC) University of Campinas Department of Structural and Functional Biology Institute of Biosciences São Paulo State University (UNESP), Botucatu D'Or Institute for Research and Education (IDOR) Instituto Nacional de Biomarcadores em Neuropsiquiatria Conselho Nacional de Desenvolvimento Científico e Tecnológico Department of Structural and Functional Biology Institute of Biosciences São Paulo State University (UNESP), Botucatu FAPESP: 20/04579-7 FAPESP: 2015/15626-8 FAPESP: 2016/18031-8 FAPESP: 2016/23328-0 FAPESP: 2017/01184-9 FAPESP: 2018/22505-0 FAPESP: 2019/00098-7 FAPESP: 2019/06372-3 FAPESP: 2020/04522-5 FAPESP: 2020/04558-0 FAPESP: 2020/04583-4 FAPESP: 2020/04746-0 FAPESP: 2020/04919-2 Fundo de Apoio ao Ensino, à Pesquisa e Extensão, Universidade Estadual de Campinas: 2274/20

Coronavirus disease-19 (COVID-19) can develop into a severe respiratory syndrome that results in up to 40% mortality. Acute lung inflammatory edema is a major pathological finding in autopsies explaining O2 diffusion failure and hypoxemia. Only dexamethasone has been shown to reduce mortality in severe cases, further supporting a role for inflammation in disease severity. SARS-CoV-2 enters cells employing angiotensin converting enzyme 2 (ACE2) as a receptor, which is highly expressed in lung alveolar cells. ACE2 is one of the components of the cellular machinery that inactivates the potent inflammatory agent bradykinin, and SARS-CoV-2 infection could interfere with the catalytic activity of ACE2, leading to accumulation of bradykinin. In this open-label, randomized clinical trial, we tested two pharmacological inhibitors of the kinin-kallikrein system that are currently approved for the treatment of hereditary angioedema, icatibant and inhibitor of C1 esterase/kallikrein, in a group of 30 patients with severe COVID-19. Neither icatibant nor inhibitor of C1 esterase/kallikrein resulted in significant changes in disease mortality and time to clinical improvement. However, both compounds promoted significant improvement of lung computed tomography scores and increased blood eosinophils, which has been reported as an indicator of disease recovery. In this small cohort, we found evidence for a beneficial role of pharmacological inhibition of the kinin-kallikrein system in two markers that indicate improved disease recovery.

COVID-19 can result in severe lung injury. It remained to be determined why diabetic individuals with uncontrolled glucose levels are more prone to develop the severe form of COVID-19. The molecular mechanism underlying SARS-CoV-2 infection and what determines the onset of the cytokine storm found in severe COVID-19 patients are unknown. Monocytes/macrophages are the most enriched immune cell types in the lungs of COVID-19 patients and appear to have a central role in the pathogenicity of the disease. These cells adapt their metabolism upon infection and become highly glycolytic, which facilitates SARS-CoV-2 replication. The infection triggers mitochondrial ROS production, which induces stabilization of hypoxia-inducible factor- 1α (HIF - 1α) and consequently promotes glycolysis. HIF- 1α-induced changes in monocyte metabolism by SARS-CoV-2 infection directly inhibit T cell response and reduce epithelial cell survival. Targeting HIF-1 ɑ may have great therapeutic potential for the development of novel drugs to treat COVID-19.

Background: the pathogenesis of severe COVID-19 involves the deregulated activation of different compartments of immunothrombosis, which are otherwise important for pathogen eradication and tissue repair. Coagulation activation, angiogenesis and alterations of endothelial barrier (EB) are elements of immunothrombosis that have been shown to be involved in the pathogenesis of COVID-19. Angiopoietins (Ang) 1 and 2 and their receptor Tie2 and VEGF-A are well-known pro-angiogenic mediators that, during inflammation also mediate EB disruption. Recently, it has also been demonstrated that the Ang/Tie2 pathway is involved in coagulation activation. Here we explored whether increased levels of angiogenesis/EB regulators (which have been previously associated with disease severity in COVID-19) are also associated with both EB disruption and coagulation activation in this condition. Methods: the study population consisted of 30 patients with COVID-19 confirmed by RT-PCR and presenting typical CT findings admitted due to hypoxemia. Thirty sex- and age-matched healthy individuals were recruited at the same time, from the same geographic region. Patients were part of a clinical trial (REBEC: U1111-1250-1843) but samples were obtained before any study intervention, within 24 hours from diagnosis confirmation. Circulating levels of angiogenesis/EB regulation mediators and coagulation biomarkers were measured by commercial assays (immunological or functional). Monolayers of endothelial cells from umbilical veins (HUVECs) or lung (HULECs) were used for measurement of EB integrity using an impedance sensor system (ECIS, Electric Cell-substrate Impedance Sensing System). Cells were stimulated with serum from patients or healthy individuals and EB integrity was continuously monitored for 36 hours. Clinical outcomes were obtained from the digital medical records. Results: mean length of hospital stay (LOS) was 12.9 ± 9.8 days. Twelve patients (40%) required intensive care (ICU) and 28/30 patients survived. Mean D-dimer was 3,609 ± 14,440 ng/mL. Circulating levels of Ang1, Ang2, sTie2 and VEGF-A were all significantly increased in patients compared to healthy individuals (Ang1: 463.2 ± 194.6 vs 237.4 ± 104.9 pg/mL, p Figure 1. In (a), endothelial barrier (EB) integrity of HUVEC monolayers upon stimulation by serum from COVID-19 patients and healthy individuals (n=27-30 per group). The lower the normalized resistance, the higher the magnitude of EB disruption. Significant differences (* to ****) are evident from 15 min to 5 hours (Anova corrected for multiple comparisons). In the lower panels, the correlation of EB disruption with clinically relevant outcomes such as length of hospital stay (b) and days of intensive care (c) are shown. Negative correlations (Spearman test) indicate that the magnitude of EB disruption is associated with worse outcomes. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

Objetivos: Os mecanismos fisiopatológicos que determinam a gravidade da Covid-19 estão associados a ativação da hemostasia e da imunidade inata, em um processo coletivamente referido como imunotrombose, e que envolve ativação plaquetária, geração de NETs (do inglês, Nucleo extracelular traps), expressão de fator tecidual, ativação do complemento e ativação endotelial. Um elemento importante da ativação endotelial é a quebra da barreira endotelial (BE), que ocorre para facilitar o acesso de leucócitos aos tecidos, onde contribuem para erradicação dos patógenos. No entanto, a avaliação da integridade da BE é desafiadora, exigindo o uso de modelos celulares. O objetivo desse estudo foi avaliar o efeito do soro de pacientes com Covid-19 sobre a integridade da BE em monocamadas de células endoteliais, e sua correlação com características clínicas da doença. Materiais e métodos: A população do estudo consistiu em 30 pacientes com Covid-19 que apresentavam comprometimento pulmonar confirmado por tomografia de tórax, e necessidade de internação hospitalar por hipoxemia e 30 controles saudáveis pareados por sexo e idade. Os pacientes recrutados fizeram parte de um estudo clínico (REBEC: U1111-1250-1843), e as amostras utilizadas nesta avaliação foram obtidas no momento da internação, antes de qualquer intervenção. Monocamadas de células endoteliais de duas fontes (HUVECs: células de cordão umbilical; HULECs: células endoteliais pulmonares) foram estimuladas com soro de pacientes e indivíduos saudáveis (diluição 15% em meio de cultura) e a integridade da BE foi avaliada por um sensor de impedância celular (ECIS; Eletric Cell-substrate Impedance Sensing System) continuamente por 36 horas. Biomarcadores de gravidade e relacionados à ativação da hemostasia foram avaliados por kits comerciais. Dados clínicos foram obtidos a partir dos prontuários digitais. Resultados: O soro de pacientes com Covid-19 induziu quebra de BE significativamente mais acentuada que o de indivíduos saudáveis em HUVECs nos tempos 15 min (p < 0,01); 30 min (p ≤ 0,001); 1h (p ≤ 0,0001); 2h (p ≤ 0,0001); 3h (p ≤ 0,0001); 4h (p ≤ 0,01) e 5h (p ≤ 0,05). Estes resultados foram confirmados no modelo de células endoteliais pulmonares (HULECs). A magnitude da quebra apresentou correlação significativa com desfechos clínicos relevantes como tempo de internação total (RS até 0.57) e tempo de UTI (RS = 0,47). Em relação a biomarcadores de interesse na Covid-19, a quebra da BE apresentou correlação significativa com neutrofilia, relação neutrófilo/linfócito, fator de Von Willebrand, fatores IX e XI, fibrinogênio, D-dímero e uPAR (Receptor de Uroquinase). Discussão: Através de um método considerado padrão-ouro para avaliação in vitro da integridade da BE nós demonstramos que componentes presentes no soro de pacientes com Covid-19 são capazes de promover a quebra da BE, e que a magnitude deste processo está relacionada à gravidade desta doença. A correlação com outros marcadores inflamatórios corrobora a conexão entre os mecanismos envolvidos na imunotrombose em pacientes com Covid-19. Conclusão: nossos resultados apontam a quebra da BE como um alvo terapêutico atrativo nestes pacientes.

Objetivos: A heme-oxigenase 1 (HO-1) é uma enzima intracelular cuja expressão é fortemente induzida por estímulos como inflamação, infecção e hemólise, e que compõe uma resposta anti-inflamatória e antioxidativa ampla, relevante para a proteção e homeostase celular em diversas condições patológicas. Sua ação específica consiste no metabolismo intracelular do heme em ferro, biliverdina e monóxido de carbono, após a captura do heme livre pela hemopexina (HPX) no meio extracelular, e a translocação deste complexo para dentro do hepatócito. Embora sugestões iniciais de uma ação direta do SARS-CoV-2 sobre a hemoglobina ou o heme já tenham sido refutadas, a ativação da HO-1 é reconhecida como parte da resposta do hospedeiro e como potencial alvo terapêutico em diversas doenças envolvendo trombose e inflamação. Assim, o objetivo deste estudo foi avaliar os níveis circulantes de hemopexina, heme e heme-oxigenase 1 na Covid-19, e avaliar a associação destes parâmetros com marcadores tromboinflamatórios e desfechos clínicos relevantes. Material e métodos: A população deste estudo consistiu em 30 pacientes com diagnóstico confirmado de Covid-19 e indicação de internação hospitalar devido a hipoxemia. O grupo controle consistiu em 30 voluntários saudáveis pareados por sexo, idade e região geográfica. A dosagem dos níveis de HO-1 e HPX foi realizada por método imunoenzimático (ELISA) utilizando kits comerciais e os níveis de heme foram medidos por método colorimétrico. A dosagem de marcadores de ativação da hemostasia foi feito por kits comerciais específicos. Resultados: Pacientes com Covid-19 apresentaram níveis aumentados de HO-1 quando comparados com controles (5.741 ± 2.696 vs 1.953 ± 612 pg/mL respectivamente, p < 0.0001), assim como uma tendência ao aumento dos níveis de HPX (3.724 ±0.8804 vs 3.254 ±1.022 mg/mL, respectivamente; p = 0.06). Além disso, observamos uma redução nos níveis de HO-1 e HPX da admissão até o 4°dia de internação. Não foram observadas diferenças nos níveis de heme no plasma de pacientes e controles em nenhum dos dois momentos. Além disso, observamos que os níveis de HO-1 na admissão estão positivamente correlacionados com parâmetros da hemostasia como TP, TTPa, fibrinogênio, FVIII:C, FVW:Ag e receptor de uroquinase (u-PAR), mas não apresentam associação evidente com parâmetros clínicos de gravidade. Discussão: Nossos dados descrevem a cinética de variação dos níveis séricos de heme, HPX e HO-1 em pacientes com Covid-19, demonstrando que à semelhança de outras infecções, a Covid-19 também se associa à indução desta via como parte da resposta anti-inflamatória. Não observamos associação entre a magnitude desta indução e a gravidade da Covid-19. Conclusão: A HO-1 pode representar um biomarcador relevante para a Covid-19, mas novos dados são necessários para subsidiar o seu uso como alvo terapêutico para estes pacientes.

Kallikrein-Kinin System; Genetic variation; Hereditary angioedema Sistema calicreina-cinina; Variació genètica; Angioedema hereditari Sistema calicreina-cinina; Variación genética; Angioedema hereditario Hereditary angioedema (HAE) is an autosomal dominant disease caused by C1-INH deficiency due to mutations in SERPING1 (C1-INH-HAE) in most of the cases, or by specific mutations in factor XII gene, F12 (F12-HAE). Identification of polymorphisms in the genes encoding proteins from key pathways driving HAE can help to understand how genetic diversity contributes to its phenotypic variability. Here, 15 genes related to the Kallikrein-Kinin System (KKS) were analyzed by next generation sequencing in 59 patients with C1-INH-HAE or F12-HAE from Brazil, Denmark and Spain, and 19 healthy relatives in a total of 31 families. We identified 211 variants, from which 23 occurred only in Danish subjects and 79 were found only in Brazilian individuals, resulting in 109/211 variations in common between European and Brazilian population in the HAE families analyzed. BDKRB2 and CPM presented a large number of variants in untranslated regions, 46/49 and 19/24, respectively; whereas ACE (n = 26), SERPING1 (n = 26), CPM (n = 24), and NOS3 (n = 16) genes presented the higher number of variants directly affecting amino acid sequence. Despite the large amount of variants identified, the lack of association between genotype and phenotype indicates that the modulation of HAE symptom requires a more complex regulation, probably involving pathways beyond the KKS, epigenetics and environmental factors. Considering the new HAE types recently described, molecules involved in the regulation of vasculature and in plasminogen activation become promising targets for future genetic studies.

Hereditary Angioedema is an autosomal dominant inherited disease leading to oedema attacks with variable severity and localization predominantly caused by C1-INH deficit. More than 400 mutations have been already identified, however no genetic analysis of a Brazilian cohort of HAE patients with C1-INH deficiency has been published. Our aim was to perform genetic analysis of C1-INH gene (SERPING1) in Brazilian HAE patients. We screened the whole SERPING1 coding region from 30 subjects out of 16 unrelated families with confirmed diagnosis of HAE due to C1-INH deficiency. Clinical diagnosis was based on symptoms and quantitative and/or functional analysis of C1-INH. We identified fifteen different mutations among which eight were not previously described according to databases. We found five small deletions (c.97_115del19; c.553delG; c.776_782del7; c.1075_1089del15 and c.1353_1354delGA), producing frameshifts leading to premature stop codons; seven missense mutations (c.498C>A; c.550G>C; c.752T>C; c.889G>A; c.1376C>A; c.1396C>T; c.1431C>A); one nonsense mutation (c.1480C>T), and two intronic alterations (c.51+1G>T; c.51+2T>C). Despite the small number of participants in this study, our results show mutations not previously identified in SERPING1 gene. This study represents the first Brazilian HAE cohort evaluated for mutations and it introduces the possibility to perform genetic analysis in case of need for differential diagnosis.

Hereditary angioedema (HAE) is accompanied by an overproduction of bradykinin (BK) as the primary mediator of swelling. Although many proteins may be involved in regulating the wide spectrum of HAE symptoms, most studies have only focused on C1-INH and FXII. For the first time, a next generation sequencing (NGS) method was applied to develop a robust, time- and cost-effective diagnostic and research tool to analyze selected genes related to HAE. The entire coding region and the exon-intron boundaries of 15 genes from 23 subjects of a Brazilian family, nine of whom were symptomatic, were analyzed by NGS. One new mutation found uniquely in the nine symptomatic patients, p.Ala457Pro in the SERPING1 gene, was estimated as likely to be pathogenic (PolyPhen-2 software analysis) and is the main candidate to be responsible for HAE in these patients. Alterations identified in a few asymptomatic individuals but also found in almost all symptomatic patients, such as p.Ile197Met (HMWK), p.Glu298Asp (NOS3) and p.Gly354Glu (B2R), may also be involved in modulating patient-specific symptoms. This NGS gene panel has proven to be a valuable tool for a quick and accurate molecular diagnosis of HAE and efficient to indicate modulators of HAE symptoms.

Background Hereditary angioedema (HAE) with normal C1 inhibitor (C1-INH) is a rare condition with clinical features similar to those of HAE with C1-INH deficiency. Mutations in the F12 gene have been identified in subsets of patients with HAE with normal C1-INH, mostly within families of European descent. Objectives Our aim was to describe clinical characteristics observed in Brazilians from 42 families with HAE and F12 gene mutations (FXII-HAE), and to compare these findings with those from other populations. Methods We evaluated a group of 195 individuals, which included 102 patients clinically diagnosed with FXII-HAE and their 93 asymptomatic relatives. Results Genetic analysis revealed that of the 195 subjects, 134 individuals (77.6% females) carried a pathogenic mutation in F12 . The T328K substitution was found in 132 individuals, and the c.971_1018+24del72 deletion was found in 2 patients. The mean age at onset of symptoms in patients with FXII-HAE was 21.1 years. The most common symptoms were subcutaneous edema (85.8% of patients), abdominal pain attacks (69.7%), and upper airway edema (32.3%). Of male individuals carrying F12 mutations, 53.3% (16 of 30) were symptomatic. Compared with reports from Europe, fewer female patients (68.6%) reported an influence of estrogen on symptoms. Conclusions Our study included a large number of patients with FXII-HAE, and, as the first such study conducted in a South American population, it highlighted significant differences between this and other study populations. The high number of symptomatic males and patients with estrogen-independent FXII-HAE found here suggests that male sex and the absence of a hormonal influence should not discourage clinicians from searching for F12 mutations in cases of HAE with normal C1-INH.

Hereditary angioedema is an autosomal dominant disease characterized by recurrent angioedema attacks with the involvement of multiple organs. The disease is unknown to many health professionals and is therefore underdiagnosed. Patients who are not adequately diagnosed and treated have an estimated mortality rate ranging from 25% to 40% due to asphyxiation by laryngeal angioedema. Intestinal angioedema is another important and incapacitating presentation that may be the main or only manifestation during an attack. In this article, a group of experts from the “Associação Brasileira de Alergia e Imunologia (ASBAI)” and the “Grupo de Estudos Brasileiro em Angioedema Hereditário (GEBRAEH)” has updated the Brazilian guidelines for the diagnosis and treatment of hereditary angioedema.