Women who are pregnant must be careful to avoid infection. Indeed, several epidemiological studies have brought to light the link between infection in pregnant women and autism disorder in their children: certain bacteria that infect a mother may lead to inflammation of the placenta and cause brain damage in her baby. What about group B streptococcus, which often affects pregnant women? Marie-Julie Allard, PhD student in neuroscience in the Department of Pediatrics at McGill University, is seeking to learn more about the bacterium in the hopes of better protecting foetuses against inflammation during pregnancy and preventing autism.
Rats born of females infected with streptococcus B showed autistic traits.
With funding from the FRQS and the Foundation of Stars, the student researcher initially demonstrated that rats born of females infected with streptococcus B showed autistic traits, for example significantly fewer cries when separated from their mothers early in their lives and far more infrequent social interactions at a young age. Interestingly, these traits were almost exclusively noted in males. This is consistent with the autism in humans since boys are four to five times more likely to be diagnosed than girls.
Allard’s findings also revealed a particular inflammatory profile in young male rats exposed to streptococcus B, including an increase in the interleukin-1 molecule. There are drugs that block the molecule, and the neuroscientist is working to ascertain whether they are safe and effective in calming placenta inflammation during pregnancy. She is currently analyzing the inflammatory cascades involved in streptococcus B infections during gestation. Her results could lead to the development of an antibiotic and anti-inflammatory drug to better protect babies against the bacteria. At the moment, pregnant women who test positive for streptococcus B at 35 weeks are prescribed an antibiotic that treats the infection but not the inflammation.