Diagnostic Mr 31/32000 proteins of Schistosoma mansoni (Sm31/32) and S. haematobium (Sh31/32): Stability and reaction conditions for prospective field tests

The existence of adult Schistosoma haematobium worm proteins (Sh31/32) homologous to the diagnostic Sm3l/32 of S. mansoni is shown. Sm31/32 and Sh31/32, adsorbed on nitrocellulose and kept dry on the bench before immunoblot analysis, were antigenically stable for at least 4 years including storage for 17 months in tropical climates. The antigens react with patient sera in the absence of defined buffers under rather simple conditions (“humid chamber blot”). The results add to the use of these antigens for serodiagnosis of schistosomiasis in endemic areas.