High levels of extracellular ATP lead to different inflammatory responses in COVID-19 patients according to the severity.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has significantly impacted the world and has driven many researchers into the pathophysiology of COVID-19. In the findings, there is a close association between purinergic signaling and the immune response. Then, this study aimed to evaluate alterations in the purinergic signaling in COVID-19 patients according to range severity. We divided the COVID-19 patients into moderate and severe cases following the guideless of NIH and WHO, together with clinical characteristics. The blood samples were collected to obtain PBMCs and platelets. We analyzed the ectonucleotidase activities through ATP, ADP, AMP, Ado hydrolysis, E-NTPDase1 (CD39), and 5'-NT (CD73) expression by flow cytometry in total leukocytes. The extracellular ATP was measured by bioluminescence, and cytokines were analyzed by flow cytometry. We observed a decrease in ATP hydrolysis and increased AMP hydrolysis in PBMCs for both groups. In severe cases, ATP hydrolysis was raised for the platelets, while ADP and AMP hydrolysis have risen significantly in both groups. Additionally, there was a significant increase in ADP hydrolysis in severe cases compared to moderate cases. In addition, we observed an increase in the ADA activity in platelets of moderate patients. Moderate and severe cases showed increased expression of CD39 and CD73 in total leukocytes. To finalize the purinergic signaling, extracellular ATP was increased in both groups. Furthermore, there was an increase in IL-2, IL-6, IL-10, and IL-17 in moderate and severe groups. Thus, for the first time, our findings confirm the changes in purinergic signaling and immune response in COVID-19, in addition to making it more evident that the severity range directly impacts these changes. Therefore, the therapeutic potential of the purinergic system must be highlighted and studied as a possible target for the treatment of SARS-CoV-2 disease. KEY MESSAGES: COVID-19 patients exhibit alterations in purinergic system and immune response. High levels of extracellular ATP lead to different inflammatory responses. CD39 and CD73 expression were increased in COVID-19 patients. Cytokines IL-2, IL-6, IL-10, and IL-17 also were altered in these patients. The purinergic system may be a possibility target to SARS-CoV-2 treatments.

Viabilidade das células-tronco mesenquimais do tecido adiposo proveniente de lipoaspirado humano / Viability of mesenchymal stem cells of adipose tissue from human liposuction

Introdução: A lipoenxertia é uma alternativa com importante aplicabilidade para reconstrução de mama e/ou correções de assimetrias decorrentes do tratamento oncológico. Esta técnica consiste na transferência de gordura autóloga, cujo estroma contém células-tronco derivadas do tecido adiposo que tem capacidade de diferenciar-se em toda a linhagem mesodermal. Para o preparo do tecido adiposo, Coleman fundamentou a centrifugação, de material aspirado por seringa, em 3000 rotações por minuto (rpm) durante 3 minutos. Contudo, estudos questionam se velocidades menores de centrifugação poderiam ser menos deletérias para viabilidade celular. Métodos: Foi realizado um estudo experimental, onde foram avaliadas as células adiposas de seis pacientes; a partir de 60mL de lipoaspirado de cada um. A amostra coletada foi fracionada em quatro tubos, e submetidos a diferentes protocolos, decantação e centrifugação nas velocidades 500, 1000 e 3000rpm por 3 minutos. Após as amostras foram processadas com colagenase IA por 30 min, submetidas ao cultivo celular por 24 horas e realizado a análise da viabilidade celular. Os resultados foram tabulados e analisados pelo teste ANOVA utilizando os programas Graphpad Prism 6.0® e SAS®. Resultados: A viabilidade celular foi maior na amostra celular centrifugada a 3000rpm e menor na amostra decantada. A coloração com Giemsa indicou manutenção da morfologia celular entre as amostras. Conclusão: As células centrifugadas na velocidade de 3000rpm apresentaram maior viabilidade celular. A centrifugação foi efetiva na compactação do tecido e eliminação de resíduos indesejados (sangue e óleo residual).

Introduction: Lipografting is an alternative with important applicability for breast reconstruction and/or corrections of asymmetries resulting from cancer treatment. This technique consists of autologous fat transfer, whose stroma contains stem cells derived from adipose tissue that can differentiate itself throughout the mesodermal lineage. For adipose tissue preparation, Coleman-based centrifugation of syringe-aspirated material at 3000 revolutions per minute (rpm) for 3 minutes. However, studies question whether lower centrifugation speeds could be less harmful to cell viability. Methods: An experimental study was conducted to evaluate the adipose cells of six patients; from 60mL of liposuction of each one. The sample collected was fractionated into four tubes and submitted to different protocols, decanting and centrifugation at speeds 500, 1000, and 3000rpm for 3 minutes. Afterward, the samples were processed with collagenase IA for 30 min, submitted to cell culture for 24 hours, and a cell viability analysis. The results were tabulated and analyzed by the ANOVA test using the Graphpad Prism 6.0® and SAS®. Results: Cell viability was higher in the cell sample centrifuged at 3000rpm and lower in the decanted sample. Giemsa staining indicated maintenance of cell morphology on the samples. Conclusion: Centrifuged cells at a speed of 3000rpm showed higher cell viability. Centrifugation was effective in compacting tissue and eliminating unwanted waste (blood and residual oil).