A new vaccine will aim to settle the symptoms of autism and alleviate gastrointestinal upsets disturbing more than 90 per cent of patients diagnosed with autism spectrum disorders.
While autism spectrum disorders (ASDs) are a complex set of conditions involving altered immune and nervous system function as well as social and behavioural development, more than 75 per cent experience chronic bouts of diarrhea.
In an effort to better understand this gastrointestinal disturbance in individuals with ASDs, research has focused attention on a particular gut bacterium, C. bolteae. While the gut is known to support a rich collection of bacteria, the proportion and abundance of particular bacteria can be used as a crude marker of a particular population. Interestingly, C. bolteae is elevated in the intestines of individuals with ASDs and as such serves as a characteristic attribute of this condition.
Given that C. bolteae is associated with an impaired ability to maintain intestinal function and has been closely connected with bouts of diarrhea, is it understandable that researchers at the University of Guelph, under the direction of chemistry professor Dr. Mario Molteiro, focused their efforts on controlling the abundance of this bacterium in the gut of individuals with ASDs.
In discussing his research, Molteiro appreciated the potential implications of the new vaccine: “This is the first vaccine designed to control constipation and diarrhea potentially caused by C. bolteae and perhaps control autism-related symptoms associated with this microbe.”
To control the population of C. bolteae researchers are turning toward the use of a vaccine for long term maintenance of the gut microbiota. While oral supplementation was effective at suppressing the abundance of C. bolteae, levels increased and symptoms returned when the treatment was removed.
Prolonged use of an antibiotic also threatens the bacteria to adapt to a modified drug-resistant form rendering the treatment ineffective after a short period of treatment.
This vaccine which is now being considered for human clinical trials relies on the carbohydrate coating the surface of the bacteria. Without this carbohydrate coating, the vaccine cannot be absorbed readily by the intestine and instead accumulates amongst the gut bacteria. Using this distinct carbohydrate surface marker, the vaccine can recognize the bacterium.
Identifying the bacterium by the distinguishable surface marker also provides a point of assessment and offers a diagnostic tool to anticipate the abundance of the bacterium in an individual’s gut. This will loosely anticipate the severity of gastrointestinal symptoms accompanying their unique condition of ASD.