In women with MS, we have found that pregnancy delays time to symptom onset, slows biological ageing, and protects against disability accumulation. However, the mechanisms underlying these long-term effects of pregnancy on MS outcomes are not well understood.
One possible mechanism is foetal microchimaerism (FMC), which is the presence and effect of foetal cells in the maternal blood or other tissues. Foetal cells enter the maternal blood throughout pregnancy and can remain detectable for decades thereafter. FMC may foster immune tolerance that may be beneficial in autoimmune diseases such as MS, and this could help explain the disparity in MS outcomes between women, and between sexes.
This research therefore aims to establish associations between FMC detected in the blood of women with MS, and their disability and biological ageing.
Dr Michael Zhong and his team have investigated the presence of foetal microchimerism (FMC) in 150 women with MS by analysing their DNA. Two different genetic marker panels were used to detect FMC, and the women's demographic data, pregnancy history, and disability scores were collected.
The analysis showed that around 30% of the women tested positive for FMC using the InDel panel, which was more sensitive than the other panel. The number of completed pregnancies was associated with FMC positivity, but there was no significant difference in FMC between women who had pregnancies before or after the onset of MS. The presence or number of microchimeric markers did not correlate with disability scores. The researchers identified a potential marker of long-term pregnancy, but it did not significantly predict disability in this study. The findings suggest that FMC can be detected in women with MS, but its relationship with disability outcomes remains unclear. Further longitudinal studies are needed to understand the effects of detectable FMC on pregnancies in women with MS.
Dr Zhong and his team have manuscripts in preparation based on these findings. They have also presented their findings at a conference, sharing their research with the scientific community, receiving feedback and input from other experts in the field.
Updated: 31 March 2023
Updated: 16 November, 2021
Laboratory research that investigates scientific theories behind the possible causes, disease progression, ways to diagnose and better treat MS.
Research that builds on fundamental scientific research to develop new therapies, medical procedures or diagnostics and advances it closer to the clinic.
Clinical research is the culmination of fundamental and translational research turning those research discoveries into treatments and interventions for people with MS.