Single strain of bacteria implicated in secondary progressive multiple sclerosis

Scientists have identified a certain species of bacteria which may drive disability progression in people with secondary progressive multiple sclerosis (SPMS) they announced in a recent presentation at the Americas Committee for Treatment and Research in Multiple Sclerosis (ACTRIMS) Forum 2023, held Feb. 23-25 in San Diego.

Due to patient protection, the team couldn’t release the name of the bacteria, instead naming it ‘bacteria X’. But when taken from SPMS patients and given to mice with MS, the rodents developed more neurological disability and more immune cells that are implicated in the inflammation behind MS.

Scientists think this species of bacteria’s flagella, which are hair-like parts it uses to move around and invade cells, are what promote the inflammation.

The research team had analysed stool samples previously from people with both relapsing remitting MS and SPMS and had found a distinct gut bacteria profile that was associated with each type.

Two different subtypes were identified within bacteria X, with one significantly more abundant in SPMS patients compared with RRMS patients and healthy people.

Whether there is a “causal relationship between gut dysbiosis and MS progression remains elusive,” said the researchers, adding that if a relationship should be confirmed, the specific “disease-enhancing causative bacteria” remain to be identified.