Recombinant subunit vaccine against Mycoplasma gallisepticum disease confers cross-protection against multiple pathogenic strains.

Mycoplasma gallisepticum (MG) is an avian respiratory pathogen of global concern, responsible for hundreds of millions of dollars in estimated economic damage each year. Given that MG is distributed across every continent except Antarctica, any globally applicable vaccine must provide protection against numerous strains. We previously published that an Rlow-based subunit vaccine reduced both MG bacterial burden and tracheal pathology in a homologous infection model using virulent MG strain Rlow. It remains unknown if the subunit vaccine could reduce disease burden induced by heterologous MG strains. To test this, we utilized a prime-boost schedule and challenged with either strain VA94 or Ap3AS. The vaccine significantly reduced disease burden induced by both heterologous strains as indicated by reduced MG burden and by reduced tracheal pathology. This demonstrates that an MG subunit vaccine has global potential.