Since 1978, List Labs products are unsurpassed in quality, consistency, and reliability for the success of your research and development project! FHA is a key virulence factor to establishing Bordetella pertussis infection. FHA, which is both surface-associated and secreted by B. pertussis, is a large (220kDa) multifunctional protein which promotes the attachment of the bacteria through several binding domains. FHA acts through multiple pathways to modulate the host immune response; an example of this type of activity is induction in macrophages of the secretion of both pro-inflammatory and anti-inflammatory cytokines. Because FHA is highly immunogenic, it is included in many acellular vaccines. List Labs FHA is purified from the native B. pertussis strain 165.