SARS-CoV-2 uses CD4 to infect T helper lymphocytes

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 mortality. 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.</p

SARS-CoV-2 uses CD4 to infect T helper lymphocytes

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 mortality. 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.</p

Nível de atividade física e aptidão cardiorrespiratória em escolares com sobrepeso/obesidade

Introduction: Childhood obesity, physical inactivity, and low physical fitness give rise early to consequences for cardiovascular and metabolic health. Objectives:To compare physical activity level (IPAQ short version) with cardiorespiratory fitness (shuttle run test) in overweight/obese children. Methods: We carried out a study in order to analyze the prevalence of overweight/obesity in 334 school-children, who were divided into two groups: G1, overweight / obese (n=39), and G2, normal weight (n=39). The IPAQ short version test and the shuttle run test were applied. Results: A total of261 students were classified as eutrophic, 56 in obese/overweight, and 17 with malnutrition/severe malnutrition. There was no significant difference in IPAQ short version (p< 0.840). In shuttle run test, G2 showed VO2max by stages (p<0.004) and meters (p <0.000) significantly higher. Conclusions: IPAQ short version was not effective for determining physical ac-tivity level of the schoolchildren, compared to the shuttle run test, and the results interpretation of shuttle run test may be more accurate if analyzed by meters