HSP60, HSP70 and HSP90 from Trichinella spiralis as targets of humoral immune response in rats

This study identifies three heat shock proteins (HSPs) using purified prepa rations from Trichinella spiralis larvae. The proteins: HSP60, HSP70 and HS P90 were found to be targets of the humoral immune response in rats. Three approaches were adopted to obtain T. spiralis HSP-enriched material and/or to purify HSPs to homogeneity. The former product was prepared using affini ty chromatography on gelatin-sepharose and elution with ATP. Pure 90 kDa-pr otein was isolated from parasite extract by sequential DEAE (A50) column ch romatograpy and preparative electrophoresis. Immunoblot analysis using mono clonal antibodies to HSP60, HSP70 and HSP90 detected the HSP60 and HSP70 in the affinity-purified product and HSP90 in the product obtained by sequent ial anionic chromatography and preparative electrophoresis. Finally, the re activy of preimmune, T. spiralis immune and irrelevant immune rat sera on i mmunoblots were also examined. Only sera taken from infected rats at time-p oints after day 7 following the first infection exhibited activity against 60, 70 and 90 kDa proteins on blots. The fact that the serum antibodies wer e anti-HSP was established by immunoadsorption of HSPs to microtiter plates coated with anti-HSP60, anti-HSP70, or anti-HSP90 and using rat sera, posi tive on blots, to also give positive scores by continued enzyme-linked immu nosorbent assay.