The protein encoded by this gene belongs to the lipocalin family. It is one of the three subunits that constitutes complement component 8 (C8), which is composed of a disulfide-linked C8 alpha-gamma heterodimer and a non-covalently associated C8 beta chain. C8 participates in the formation of the membrane attack complex (MAC) on bacterial cell membranes. While subunits alpha and beta play a role in complement-mediated bacterial killing, the gamma subunit is not required for the bactericidal activity.