Isolation and characterization of a neutrophil chemotactic factor from Tritrichomonas foetus organisms.

A neutrophil chemotactic factor (TfNCF) was isolated from the crude extract of Tritrichomonas foetus organisms by a combination of anion-exchange chromatography on DE52 and gel filtration on Sephacryl S200. TfNCF showed homogenicity by both PAGE and SDS-PAGE. The molecular weight of TfNCF was estimated to be 22 and 24 kDa, by Sephacryl S200 gel chromatography and by SDS-PAGE under reducing conditions. Immunization of TfNCF caused almost complete protection against T. foetus infection in mice. Western blot analysis probed with anti-TfNCF antibody showed that the epitopes on TfNCF were not commonly shared on the other components of T. foetus organisms nor other helminthous parasite-derived components. Furthermore, pre-incubation of neutrophils with antigens of other helminthous parasites or N-formylmethionyl-leucyl-phenylalanine did not affect the neutrophil chemotactic activity for TfNCF. These results suggest that TfNCF is a novel NCF consisting of unique epitopes for both antigenicity and neutrophil chemotactic activity. The role of NCF in the initiation of the immune response is discussed.