Stage-specific serine and metallo-proteinase release by adult and larval Trichostrongylus vitrinus.

Proteinases were released in a stage-specific manner during in vitro culture by 4th larval stage and adult Trichostrongylus vitrinus. Substrate gel analyses and inhibitor studies revealed the presence of serine and metallo-proteinases, active over a broad pH range, which degraded proteins such as fibrinogen, plasminogen and fibronectin but not immunoglobulin. The adult proteinases were partially inhibited (43%) by immunoglobulin from immune lamb lymph compared to controls, indicating their relevance to parasite immunobiology in vivo.