Immunopathogenesis of patients with COVID-19: from the perspective of immune system 'evolution' and 'revolution'.

The pandemic caused by severe acute respiratory syndrome coronavirus 2 is sweeping the world, threatening millions of lives and drastically altering our ways of living. According to current studies, failure to either activate or eliminate inflammatory responses timely and properly at certain stages could result in the progression of the disease. In other words, robust immune responses to coronavirus disease 2019 (COVID-19) are critical. However, they do not theoretically present in some special groups of people, including the young, the aged, patients with autoimmunity or cancer. Differences also do occur between men and women. Our immune system evolves to ensure delicate coordination at different stages of life. The innate immune cells mainly consisted of myeloid lineage cells, including neutrophils, basophils, eosinophils, dendritic cells and mast cells; they possess phagocytic capacity to different degrees at different stages of life. They are firstly recruited upon infection and may activate the adaptive immunity when needed. The adaptive immune cells, on the other way, are comprised mainly of lymphoid lineages. As one grows up, the adaptive immunity matures and expands its memory repertoire, accompanied by an adjustment in quantity and quality. In this review, we would summarise and analyse the immunological characteristics of these groups from the perspective of the immune system 'evolution' as well as 'revolution' that has been studied and speculated so far, which would aid the comprehensive understanding of COVID-19 and personalised-treatment strategy.

Exploring the Immunopathogenesis of Pregnancy With COVID-19 at the Vaccination Era.

Since December 2019, Wuhan, China, has experienced an outbreak of coronavirus disease (COVID-19), which is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Pregnant women are deductively considered to be in immunosuppressive condition for the safety of semi-allograft fetuses, which increases the risk of being infected by the virus. In this review, we analyzed the unique immunological characteristics of pregnant women and reviewed their known outcomes at different trimesters from the perspective of underlying mechanisms that have been studied and speculated so far.

Molecular evidence suggesting the persistence of residual SARS-CoV-2 and immune responses in the placentas of pregnant patients recovered from COVID-19.

OBJECTIVES: Recent studies have shown the presence of SARS-CoV-2 in the tissues of clinically recovered patients and persistent immune symptoms in discharged patients for up to several months. Pregnant patients were shown to be a high-risk group for COVID-19. Based on these findings, we assessed SARS-CoV-2 nucleic acid and protein retention in the placentas of pregnant women who had fully recovered from COVID-19 and cytokine fluctuations in maternal and foetal tissues. MATERIALS AND METHODS: Remnant SARS-CoV-2 in the term placenta was detected using nucleic acid amplification and immunohistochemical staining of the SARS-CoV-2 protein. The infiltration of CD14+ macrophages into the placental villi was detected by immunostaining. The cytokines in the placenta, maternal plasma, neonatal umbilical cord, cord blood and amniotic fluid specimens at delivery were profiled using the Luminex assay. RESULTS: Residual SARS-CoV-2 nucleic acid and protein were detected in the term placentas of recovered pregnant women. The infiltration of CD14+ macrophages into the placental villi of the recovered pregnant women was higher than that in the controls. Furthermore, the cytokine levels in the placenta, maternal plasma, neonatal umbilical cord, cord blood and amniotic fluid specimens fluctuated significantly. CONCLUSIONS: Our study showed that SARS-CoV-2 nucleic acid (in one patient) and protein (in five patients) were present in the placentas of clinically recovered pregnant patients for more than 3 months after diagnosis. The immune responses induced by the virus may lead to prolonged and persistent symptoms in the maternal plasma, placenta, umbilical cord, cord blood and amniotic fluid.

COVID-19 and Pregnancy: A Case Study.

The 2019 novel coronavirus disease is spreading all over the world. Pregnant women and infants require particular concern, owing to the special immune conditions. A case of a pregnant woman who was exposed to SARS-CoV-2 at 34+1 weeks gestation and chose to continue pregnancy is reported. Without obvious symptoms or signs, the woman did not receive any treatment before delivery, and gave birth at 37+5 weeks to a neonate with positive immunoglobulin G for SARS-CoV-2 and negative nucleic acid tests. The mother was given anti-infection, oxytocin, and fluid rehydration treatment after delivery. Both mother and infant recovered well after a three-month follow-up. Continued expectation to deliver at term instead of preterm can decrease the potential risk of severe perinatal and infant complications and is beneficial to the development of the neonate. More studies are required to confirm the presence of vertical transmission.

Clinical manifestations and maternal and perinatal outcomes with COVID-19.

Coronavirus disease 2019 (COVID-19) is a novel type of highly contagious pneumonia caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As the COVID-19 outbreak unfolds, more and more pregnant women are infected with SARS-CoV-2, concerns have been raised about its clinical manifestations in pregnancy and the potential risk of vertical transmission from mother to fetus in pregnant women. Hence, in this review, we summarize the latest research progress related to COVID-19 epidemiology and the reported data of pregnant women with COVID-19 and discuss the clinical manifestations, treatments, maternal and perinatal outcomes, and intrauterine vertical transmission potential of such virus. Reported data suggest that symptoms in pregnant women are similar to those in other populations and that there is no evidence of vertical transmission from mother to child. In the meantime, considering the good prognosis of most of the infected mothers and infants and absence of serious obstetric complications in pregnant women with COVID-19, it is not recommended to give birth as soon as possible, and it is necessary to extend the gestational period reasonably.

Management of Pregnancy during the COVID-19 Pandemic.

Coronavirus disease 2019 (COVID-19) is spreading worldwide. All aspects of pregnancy management from conception to delivery to puerperium as risks facing newborns are herein, reviewed. Maternal home management and prenatal care management protection, delivery timing or mode selection, delivery process management, and subsequent puerperal protection are crucial. In this Review, the features and treatment strategies, especially emphasizing the safety of antiviral drugs for pregnant women, the wearing of face masks, and practicing of personal hygiene (e.g., handwashing, disinfection, home cleaning, and ventilation) are reviewed as essential protective measures. It is recommended to provide online consultation, telemedicine, and remote fetal heart rate monitoring and set the flow point for prenatal examination to encourage prenatal examination at home or postponing examinations (except nuchal translucency at 11-13+6 weeks, Oscar Test at 16 weeks, and fetal ultrasound at 20-24 weeks). It is shown that the precise formulation of follow-up strategies for pregnant women with COVID-19 is necessary.

Clinical features and obstetric and neonatal outcomes of pregnant patients with COVID-19 in Wuhan, China: a retrospective, single-centre, descriptive study.

BACKGROUND: In December, 2019, coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, China. The number of affected pregnant women is increasing, but scarce information is available about the clinical features of COVID-19 in pregnancy. This study aimed to clarify the clinical features and obstetric and neonatal outcomes of pregnant patients with COVID-19. METHODS: In this retrospective, single-centre study, we included all pregnant women with COVID-19 who were admitted to Tongji Hospital in Wuhan, China. Clinical features, treatments, and maternal and fetal outcomes were assessed. FINDINGS: Seven patients, admitted to Tongji Hospital from Jan 1, to Feb 8, 2020, were included in our study. The mean age of the patients was 32 years (range 29-34 years) and the mean gestational age was 39 weeks plus 1 day (range 37 weeks to 41 weeks plus 2 days). Clinical manifestations were fever (six [86%] patients), cough (one [14%] patient), shortness of breath (one [14%] patient), and diarrhoea (one [14%] patient). All the patients had caesarean section within 3 days of clinical presentation with an average gestational age of 39 weeks plus 2 days. The final date of follow-up was Feb 12, 2020. The outcomes of the pregnant women and neonates were good. Three neonates were tested for SARS-CoV-2 and one neonate was infected with SARS-CoV-2 36 h after birth. INTERPRETATION: The maternal, fetal, and neonatal outcomes of patients who were infected in late pregnancy appeared very good, and these outcomes were achieved with intensive, active management that might be the best practice in the absence of more robust data. The clinical characteristics of these patients with COVID-19 during pregnancy were similar to those of non-pregnant adults with COVID-19 that have been reported in the literature. FUNDING: National Natural Science Foundation of China, Hubei Provincial Natural Science Foundation of China.