α 2 -macroglobulin: an evolutionarily conserved arm of the innate immune system

All animals and plants have immune systems that protect them from the diversity of pathogens that would otherwise threaten their survival. The different components of the immune system may inactivate the pathogens themselves or promote the inactivation and clearance of toxic products produced by the pathogens. An important category of virulence factors of bacterial and prokaryotic pathogens are the proteases, which act to facilitate the invasion...