EXPRESSION OF A 70-KDA HEAT-SHOCK-RELATED PROTEIN DURING TRANSFORMATION FROM FREE-LIVING INFECTIVE LARVAE TO THE PARASITIC STAGE IN STRONGYLOIDES VENEZUELENSIS

The in vitro transformation system of Strongyloides venezuelensis has been established which induces free-living infective larvae to transfo rm into the parasitic stage by a temperature shift from 25 to 37 degre es C. Comparison of the profiles of proteins labeled with [S-35]-methi onine in infective larvae at 25 and 37 degrees C with marked morpholog ical transformation revealed an increase in the 70-kDa protein, thus s howing these proteins to be related to the family of heat-shock protei ns. In addition, the new appearance of two complexes between 16-kDa an d 22-kDa proteins was observed. The 70-kDa protein cross-reacted with monoclonal antibody against human heat-shock protein 70, which was con stitutively expressed. These proteins, synthesized during the transfor mation of S. venezuelensis from the infective larval stage to the para sitic stage, might be crucial for biochemical events that regulate the infectivity of the parasite for the host.