Immune avoidance and the carrier state

Many pathogenic microorganisms evade host immunity through variability in surface proteins targeted by protective antibodies. The SeM protein of S. equi is an important virulence factor located on the bacterial surface. We recently found that the N-terminal region of SeM is subjected to variation.

We propose that this SeM variability helps the bacterium to persist in carrier horses.

A new Horserace Betting Levy Board-funded project will determine if this is the case and will help us to ensure that future strangles vaccines are effective against a wide range of S. equi sub-types.