1122 GMT June 19, 2019
"Our study offers potential links between changes in the offspring's immune system and the increased susceptibility and incidence of these diseases later in life," said Messaoudi, Science Daily wrote.
The researchers used established body mass index (BMI) categories to sort the mothers participating in the study, BMI being a number calculated from height and weight. A mother was considered overweight when her BMI was 25 to 29.9. A mother was considered obese when her BMI was 30 or higher.
The mothers were all non-smoking, had no diabetes, and had an uncomplicated gestation at term. Each mother delivered just one baby. Eleven mothers were lean, 14 were overweight, and 14 were obese. Thirty were white, three were Asian American/Pacific Islander, one was an American-Indian/Alaskan native, and two were African American. The racial identity of three women was unknown.
"We found that very specific immune cells in circulation — monocytes and dendritic cells — isolated from babies born to moms with high BMI were unable to respond to bacterial antigens compared to babies born to lean moms," Messaoudi said. "Such babies also showed a reduction in CD4 T-cells. Both of these changes could result in compromised responses to infection and vaccination."
Further, the researchers found that cells (eosinophils) that play a role in allergic response and asthma pathogenesis were significantly reduced in the umbilical cord blood of babies born to obese mothers. One potential explanation for these observations is that these cells have already moved into the lungs, which could explain the increased incidence of asthma observed later in life in children born to obese mothers.
The research is the first to show the link between maternal obesity during pregnancy and neonatal immune outcomes, and shows that changes in immunity are already detectable at birth and could persist for the lifetime of the child into adulthood.