RESUMEN
Even after two years of the pandemic, a completely effective treatment against SARS-CoV-2 has not yet been established. Considering this fact and the emergence of successive new viral variants, the development of therapies based on natural polyclonal antibodies recovered from convalescent plasma remains relevant. This study presents a comparison between different methods of screening antibodies in samples of 41 individuals previously diagnosed with COVID-19. We found a significant correlation between Abbot Architect anti-SARS-CoV-2 IgG and Abbott Allinity SARS-CoV-2 IgG II Quantitative assay intensity of reactivity and neutralizing antibody (nAb) titers. Thus, we propose an initial antibody screening with IgG anti-N Abbott Architect test, with an index of, for example, > 3.25 or SARS-CoV-2 IgG II Quantitative Abbott Allinity assay > 137.65 AU/mL as good predictors of Nab ≥ 1:80. For the quantitative method, this threshold demonstrated a 100 % sensitivity and 80 % specificity, with 97.3 % accuracy. An interesting observation was the increase in the neutralizing activity of the anti-SARS-CoV-2 antibodies with the longest interval between the end of the symptoms and the collection, demonstrating that the delay in plasma collection does not affect the achievement of adequate nAbs levels. These results demonstrate the possibility of using faster and more widely available commercial serological tests with a good correlation with viral neutralization tests in culture, allowing for optimized large-scale donor selection, which will be of utmost importance for the development of therapies such as hyperimmune immunoglobulin.
Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/terapia , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Inmunoglobulina G , Sueroterapia para COVID-19RESUMEN
INTRODUCTION: Dendritic cell (DC) vaccines have demonstrated good efficacy in preventing relapse and in increasing survival of patients affected by a variety of both solid and hematological tumors. Most protocols used to generate these cells involve the automated separation of peripheral blood monocytes from patients. This approach requires specialized equipment, which elevates the cost of this type of therapy, potentially limiting the widespread access to patients. METHOD: In this study, we compare the yield and quality of dendritic cells generated from monocytes and isolated by an automated method or by manual methods using gradient centrifugation. RESULTS: The results demonstrate the equivalence of the 3 methods in relation to the yield and final quality of the product, however with considerable differences between the costs of these procedures. In addition, this study also demonstrates the feasibility of the antigenic pulse with autologous tumor cell lysates, constituting a source of antigens, not only easily obtained and manipulated, but also specific to the patient's tumor. CONCLUSION: These findings may have important implications for emerging centers interested in using this medical approach and potentially increase the access of a greater number of patients to this therapeutic option.
RESUMEN
Despite being initially considered at higher risk for severe COVID-19, sickle cell disease (SCD) patients have mostly presented clinical severity similar to the general population. As their vulnerability to become infected remains uncertain, we assessed the seroreactivity for SARS-CoV-2 to estimate the prevalence of infection and possible phenotypic and socioeconomic determinants for their contagion. Serologic evaluation was performed on 135 patients with an overall prevalence of 11%; positivity was associated with older age and use of public transportation. We speculate that social distancing instructions recommended by our clinic may have contributed to lower levels of infection, but potential protection factors need further investigation.
RESUMEN
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.
RESUMEN
Introduction Dendritic cell (DC) vaccines have demonstrated good efficacy in preventing relapse and in increasing survival of patients affected by a variety of both solid and hematological tumors. Most protocols used to generate these cells involve the automated separation of peripheral blood monocytes from patients. This approach requires specialized equipment, which elevates the cost of this type of therapy, potentially limiting the widespread access to patients. Method: In this study, we compare the yield and quality of dendritic cells generated from monocytes and isolated by an automated method or by manual methods using gradient centrifugation. Results The results demonstrate the equivalence of the 3 methods in relation to the yield and final quality of the product, however with considerable differences between the costs of these procedures. In addition, this study also demonstrates the feasibility of the antigenic pulse with autologous tumor cell lysates, constituting a source of antigens, not only easily obtained and manipulated, but also specific to the patient's tumor. Conclusion These findings may have important implications for emerging centers interested in using this medical approach and potentially increase the access of a greater number of patients to this therapeutic option.