Assessment of reactivities of $ phoid fever sera s 3 - 2 against outer membrane protein preparations from strains of Salmonella typhi in Jakarta

An attempt was caruied out to assess reactivity of sera from patients with typhoid fever against outer membrane protein (OMp) preparations tlerived from local strain of Salmonella typhi. OMPs from l0 clinical isoLates of S. typhi were isolatetl by sonication and through the use of buffer containing Triton X-100 2Vo. SDS-PAGE of these OMPs showed six dffirent electrophoretic profiles in whiclt major proteins with molecular weight (MW) 38, 37 and 34 kDa corresportding to OmpC, OmpF ancl OmpA respectit,eLy were present itt most of the OMPs. Three isolates of S. typhi, however, ditL not show the 34 kDa protein. Although txot as prominent, polypeptitle with MW 20.5 kDa was observed in all OMPs while polypeptide with MW 25 and 29 kDa in 4 ancl 6 OMP preparations respectively. Intmunoblotting of the OMPs with immunisecl rabbils\era showed strong reactivity against the porins, the 37, 38 kDa, antl the 29 kDA polypeptide. Sera from patients with typhoitl fever contained IgM antibodies which did not react with tlrc porirzs and the OmpA, howetter, they showed reactivity to the minor poLypeptides.