Significantly elevated levels of some genes and proteins associated with increased immune activation may help protect male fetuses from infection with SARS-CoV-2 in utero, but the resulting inflammation may pose risks to the fetus and child, more precisely, the male placenta enhances the activation of pro-inflammatory cytokine genes More than the female placenta, according to Andrea Idlow, senior study author and maternal-fetal medicine specialist at Harvard-affiliated Massachusetts General Hospital (MGH).
The study shows that, moreover, pregnant women infected with “Covid-19” transmitted much less immunity from the virus to male fetuses compared to female fetuses, which may affect the infant’s risk of infection with SARS-CoV-2 virus.
“The gender of the fetus affected the mother’s ability to produce and transmit COVID-19 antibodies to her child,” Idlow says.
This is the first study to examine gender differences in the transmission of maternal antibodies from MERS-CoV infection to her fetus, and the first to examine gender differences in the placenta’s response to maternal infection.
Epidemiological studies have shown that adult males, children and infants have a higher prevalence of COVID-19 infection and develop more severe disease than females. Also, male fetuses and infants are more susceptible to a range of prenatal and perinatal exposures than female infants, so Idlow and her team sought to screen the placenta, maternal blood and umbilical cord blood from pregnancies affected by maternal infection.
The study included 68 pregnant women, 38 of whom were infected with SARS-CoV-2 during the third trimester of pregnancy before the development of “Covid-19” vaccines. The remaining 30 participants were healthy pregnant women who tested negative for SARS-CoV-2 during pregnancy. In both groups, half of the fetuses were male and half were female.
In a new discovery, Idlow and colleagues show that, compared to female fetuses, the placentas of male fetuses carried by women with COVID-19 have significantly higher expression of interferon-stimulating genes (ISGs), which play a key role in protecting fetuses from viral invaders in the womb.
However, increased expression of ISGs and the subsequent production of immune cells called cytokines can also lead to an intrauterine inflammatory environment, which has been associated with an increased risk of neurodevelopmental or metabolic diseases later in life.
“Although our study did not specifically assess these risks, it increases the importance of following these children and looking at male and female fetuses differently,” Idlow explains.
In a second important discovery, Edlow’s team showed that mothers with Covid-19 who had male fetuses made lower levels of antibodies against the virus compared to mothers with female fetuses. They also pass on fewer antibodies to the male fetus.
This suggests that males may be more susceptible to SARS-CoV-2 infection in infancy, and that the gender of the fetus can influence the mother’s immune response to the virus, Idlow says.
Idlow and her colleagues plan to examine the nature of the antibodies caused by the Covid-19 vaccine, and how it is affected by the timing of the vaccine during pregnancy and of course the sex of the fetus. “We want to know what happens to the placenta when mothers are vaccinated against COVID-19 at each trimester and how the gender of the fetus affects this response,” she said.
Source: Express – Russia Today