The potential use of 29 kDa protein as a marker of pathogenicity and diagnosis of symptomatic infections with Blastocystis hominis.

The present study was performed to characterize the protein profiles of Blastocystis hominis isolates from symptomatic and asymptomatic individuals by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting using sera from symptomatic and asymptomatic patients. The presence of immunogenic bands associated with pathogenicity or of diagnostic potentials was also evaluated. The study comprised 80 individuals classified into four groups, 20 each: symptomatic blastocystosis (G1), asymptomatic blastocystosis (G2), other parasitic infections (G3), and healthy control subjects (G4). SDS-PAGE analysis of individual antigens form symptomatic and asymptomatic B. hominis isolates revealed similar and distinctive antigenic bands with significant differences in two high (123.5 and 112.3 kDa) and few low molecular weight bands (48.5, 38, 42.3, and 35.5 kDa). Immunoblotting was performed using symptomatic and asymptomatic antigen pools with sera of the four studied groups. It was found that anti-B. hominis IgG reacted with nine protein bands ranging from 100 to 18 kDa of the symptomatic antigen pool. There was a significant difference between G1 and G2 in the recognition of 64, 56, 38, and 29 kDa antigen bands. Also, anti-B. hominis IgG reacted with five protein bands ranging from 56 to 12 kDa of asymptomatic antigen pool. There was a significant difference between G1 and G2 in the recognition of 29 kDa antigen band. These findings suggest the potential use of the 29-kDa antigen as marker of pathogenicity and implicate its use in the diagnosis and differentiation between symptomatic and asymptomatic blastocystosis.

Duration of peginterferon therapy in acute hepatitis C: a randomized trial.

Spontaneous resolution of acute hepatitis C virus infection cannot be predicted, and chronic evolution of the disease occurs in a majority of cases. To assess the efficacy and safety of peginterferon alpha-2b administered for 8, 12, or 24 weeks in patients with acute hepatitis C virus infection a total of 161 patients were identified with acute hepatitis C virus infection. Of these, 30 patients refused treatment but were retained in the study as a nonrandomized comparison group. Of the 131 patients who consented to treatment, 29 patients spontaneously resolved, leaving 102 patients randomly assigned to peginterferon alpha-2b (1.5 microg/kg) for 8 weeks (group A; n=34), 12 weeks (group B; n=34), and 24 weeks (group C; n=34). The primary end point was sustained virologic response. An intent-to-treat analysis was used for efficacy and safety end points. Sustained virologic response was achieved in 23/34 (67.6%), 28/34 (82.4%), and 31/34 (91.2%) of patients in groups A, B, and C, respectively; all had undetectable hepatitis C virus RNA 48 weeks after the end of therapy. Treatment for 8 or 12 weeks was effective in genotypes 2, 3, and 4, whereas genotype 1 required 24 weeks of therapy. The 8- and 12-week regimens were associated with fewer adverse events compared with the 24-week regimen. In conclusion, peginterferon alpha-2b effectively induces high sustained virologic response rates in patients with acute hepatitis C virus infection, thus preventing development of chronic hepatitis C. Duration of treatment should be further optimized based on genotype and rapid virologic response at week 4.

Peginterferon alfa-2b therapy in acute hepatitis C: impact of onset of therapy on sustained virologic response.

BACKGROUND & AIMS: Pegylated interferon therapy has not been adequately evaluated in acute hepatitis C virus (HCV) infection. This randomized trial assessed the efficacy, safety, and timing of pegylated interferon alfa-2b for treatment of acute hepatitis C. METHODS: One hundred seventy-five patients acutely infected with HCV were screened. Patients whose infection did not spontaneously resolve by week 8 were randomized to once weekly peginterferon alfa-2b monotherapy (1.5 microg/kg per week) started at weeks 8, 12, or 20 for a duration of 12 weeks. The primary endpoint was undetectable HCV RNA 24 weeks after the end of treatment (sustained virologic response [SVR]). All patients were followed for 48 weeks after cessation of therapy. RESULTS: One hundred twenty-nine subjects started treatment at week 8 (group A, n = 43), week 12 (group B, n = 43), or week 20 (group C, n = 43). By using an intent-to-treat analysis, the overall SVR rate was 87%. The SVR rates were 95%, 92%, and 76% with treatment onset at 8, 12, and 20 weeks, respectively. Overall, SVR rates were better for patients infected with genotypes 2, 3, and 4 than those infected with genotype 1. Earlier initiation of therapy improved SVR rates for patients infected with genotype 1 with high viral load. Peginterferon alfa-2b was well tolerated. Subjects with SVR maintained undetectable HCV RNA 48 weeks after therapy. CONCLUSIONS: Peginterferon alfa-2b monotherapy in acute hepatitis C induces high sustained virologic response rates, prevents chronic evolution, and is well tolerated. Initiation of treatment at week 8 or 12 results in higher sustained virologic rates than initiation at week 20.

Characterization of specific Trichomonas vaginalis target antigens from different isolates by immunoblotting against hyperimmune rabbit serum.

The SDS-PAGE and immunoblot methods were used to identify Trichomonas vaginalis specific target antigen(s). Ten T. vaginalis isolates, cultured on TYM media, were analyzed by Sodium Dodecyl Sulphate Poly Acrylamide Gel Electrophoresis (SDS-PAGE), revealed 34 distinct bands. Immunoblotting against a hyperimmune rabbit serum, showed 20 reactive bands ranging from 14-205 kDa. There was isolate to isolate variability among 8 isolates, while 2 isolates (6,7) showed a similar antigenic patterns. Imunoblotting of the isolates showed a total of 20 molecular weight bands, 80% of isolates gave positive immunologic reactions above 100 kDa, while below 100 Kda all the isolates recognized the different molecular weight bands. Out of 20 reacting bands, 5 main bands were detected, 29, 66, 84, 95 & 115 kDa gave positive percent of 60, 60, 60, 90 & 80% among the 10 isolates respectively.

Compatibility of Biomphalaria alexandrina snails to infection with Schistosoma mansoni after exposure to sublethal concentrations of Myrrh.

The effect of exposing B. alexandrina to sub-lethal dose (LC10 & LC20) of Myrrh, on its susceptibility to infection with S. mansoni miracidia were determined. Starting three weeks post miracidial exposure, cercarial shedding was monitored. No shedding of cercariae were observed from snails treated with LC20. In snails treated with LC10, longer prepatent cercarial and shorter cercarial production periods than those of control group were recorded. The number of infected snails and of shedding cercariae were decreased. The study revealed that sublethal values of myrrh decreased the compatibility of B. alexandrina to S. mansoni infection thus playing an important role in the control of schistosomiasis.

Immunoblot analysis of Trichomonas vaginalis antigens recognized by rabbit hyperimmune serum raised against exoantignes.

The SDS-PAGE and immunoblot were used to identify Trichomonas vaginalis antigenic epitopes present in purified somatic and exo-antigens. The presence of common immunogenic proteins corresponding to molecular weights of 76, 60 and 23 kDa was revealed. Distinctive immunogenic bands of 92, 72, 55 and 40 kDa for the exo-antigens, and of 110, 80, 78 and 50 kDa for the somatic antigens, appeared when the antigens were probed by the homologous immune rabbit serum.