 Therefore, in many pathogenic microbes (for example, in "Cryptococcus neoformans", a fungus) melanins appear to play important roles in virulence and pathogenicity by protecting the microbe against immune responses of its host.In invertebrates, a major aspect of the innate immune defense system against invading pathogens involves melanin.Within minutes after infection, the microbe is encapsulated within melanin (melanization), and the generation of free radical byproducts during the formation of this capsule is thought to aid in killing them.