Since the COVID-19 outbreak was acknowledged by the WHO on 30 January 2020, much research has been conducted to unveil various features of the responsible SARS-CoV-2 virus. Different rates of contagion in adults, children, and pregnant women may guide us to understand the underlying infection conditions of COVID-19. In this study, we first provide a review of recent reports of COVID-19 clinical outcomes in children and pregnant women. We then suggest a mechanism that explains the curious case of COVID-19 in children/pregnant women. The unique stem cell molecular signature, as well as the very low expression of angiotensin-converting enzyme 2 and the lower ACE/ACE2 ratio in stem cells of children/pregnant women compared to adults might be the cause of milder symptoms of COVID-19 in them. This study provides the main molecular keys on how stem cells can function properly and exert their immunomodulatory and regenerative effects in COVID-19-infected children/pregnant women, while failing to replicate their role in adults. This can lay the groundwork for both predicting the pattern of spread and severity of the symptoms in a population and designing novel stem cell-based treatment and prevention strategies for COVID-19.
【저자키워드】 COVID-19, children, cell cycle, pregnant women, quiescent stem cell, active stem cells, ACE/ACE2, 【초록키워드】 Treatment, stem cells, severity, Infection, SARS-CoV-2 virus, Symptom, angiotensin-converting enzyme 2, Clinical outcome, pregnant women, Spread, Adults, COVID-19 outbreak, immunomodulatory, Research, women, molecular, pattern, mechanism, Angiotensin-converting enzyme, angiotensin, Contagion, stem cell, low expression, symptoms of COVID-19, feature, Cell, responsible, conducted, replicate, provide, condition, unique, the WHO, explain, regenerative effect, 【제목키워드】 SARS-CoV-2, review, role, STEM,