BOSTON: Scientists have found evidence of a lower-than-expected transfer of protective antibodies against the new coronavirus through the placenta of infected mothers during the third trimester, findings that shed light on the critical windows of pregnancy that they may be the most desirable for vaccination.
According to researchers, including those at Massachusetts General Hospital (MGH) in the United States, the findings can be explained by a process in which the body’s carbohydrate molecules alter antibodies after their production.
They explained that alterations in the binding of carbohydrates to specific antibodies to coronavirus (a process called glycosylation) may be to blame for the reduced transfer from the mother to the fetus.
In the study, published in the journal Cell, the scientists compared maternal antibodies against the flu (flu), whooping cough (whooping cough) and the new coronavirus (SARS-CoV-2) and how these antibodies were transferred to the placenta.
They found that flu-specific antibodies and whooping cough were actively transferred in a relatively normal way.
In contrast, the researchers said that the transfer of specific SARS-CoV-2 antibodies to the baby was not only significantly reduced, but the transferred antibodies were less functional than those against influenza.
According to scientists, the reduced transfer was only observed in the third trimester infection.
The study found that carbohydrate attachments in specific SARS-CoV-2 antibodies in maternal blood were different from those observed in flu-specific and pertussis antibodies.
Researchers believe that this pattern of carbohydrates can cause COVID-specific antibodies to become “trapped” in the maternal circulation rather than being transferred through the placenta via placental antibody receptors.
However, the scientists said that some increases in the total number of maternal antibodies induced by viral infection helped to partially overcome the problem and facilitate the transfer of some functional antibodies from the mother to the fetus.
The study noted that higher placental expression of a receptor that attracts the carbohydrate pattern of SARS-CoV-2-specific antibodies.
According to the analysis, the scientists said some of the antibodies that transferred the best were also the most functional, activating the killer natural cells of the immune system that could help the newborn fight the virus if exposed.
Researchers believe the findings have implications for the design of new SARS-CoV-2 candidate vaccines for pregnant women.
“Vaccine regimens capable of driving high levels of COVID-specific antibodies with placental-favored glycosylation patterns for selective transfer to the fetus may lead to better neonatal and infant protection,” says Andrea Edlow, co-author of the study , specialist at Massachusetts General Hospital.
The scientists said the results of the study may point to critical phenomena in pregnancy that may be more desirable for vaccination to optimize the protection of both the mother and her baby.
According to researchers, including those at Massachusetts General Hospital (MGH) in the United States, the findings can be explained by a process in which the body’s carbohydrate molecules alter antibodies after their production.
They explained that alterations in the binding of carbohydrates to specific antibodies to coronavirus (a process called glycosylation) may be to blame for the reduced transfer from the mother to the fetus.
In the study, published in the journal Cell, the scientists compared maternal antibodies against the flu (flu), whooping cough (whooping cough) and the new coronavirus (SARS-CoV-2) and how these antibodies were transferred to the placenta.
They found that flu-specific antibodies and whooping cough were actively transferred in a relatively normal way.
In contrast, the researchers said that the transfer of specific SARS-CoV-2 antibodies to the baby was not only significantly reduced, but the transferred antibodies were less functional than those against influenza.
According to scientists, the reduced transfer was only observed in the third trimester infection.
The study found that carbohydrate attachments in specific SARS-CoV-2 antibodies in maternal blood were different from those observed in flu-specific and pertussis antibodies.
Researchers believe that this pattern of carbohydrates can cause COVID-specific antibodies to become “trapped” in the maternal circulation rather than being transferred through the placenta via placental antibody receptors.
However, the scientists said that some increases in the total number of maternal antibodies induced by viral infection helped to partially overcome the problem and facilitate the transfer of some functional antibodies from the mother to the fetus.
The study noted that higher placental expression of a receptor that attracts the carbohydrate pattern of SARS-CoV-2-specific antibodies.
According to the analysis, the scientists said some of the antibodies that transferred the best were also the most functional, activating the killer natural cells of the immune system that could help the newborn fight the virus if exposed.
Researchers believe the findings have implications for the design of new SARS-CoV-2 candidate vaccines for pregnant women.
“Vaccine regimens capable of driving high levels of COVID-specific antibodies with placental-favored glycosylation patterns for selective transfer to the fetus may lead to better neonatal and infant protection,” says Andrea Edlow, co-author of the study , specialist at Massachusetts General Hospital.
The scientists said the results of the study may point to critical phenomena in pregnancy that may be more desirable for vaccination to optimize the protection of both the mother and her baby.