Molecular characterization of Egyptian human and anima Echinococcus granulosus isolates by RAPD-PCR technique.

Five primers of known, but arbitrary nucleotide sequence (OPH-03, OPH-05, OPH-12, OPH-15, OPH-18) were used to detect genetic variability in Egyptian human, camel and pig E. granulosus isolates. OPH-03, OPH-05 & OPH-15 proved useful as genetic markers of strain variation, while OPH-12 and OPH-18 allowed distinction at the genus level i.e. diversified from Cysticercus tenuicollis. OPH-03 was the most effective giving sharp distinct banding pattern and the least values of similarity coefficients. Some variations were detected within E. granulosus isolates from the same host. The level of heterogeneity was low in three of the human isolates, camel and pig strains. Individual variation was detectable within other 3 human isolates. Human and camel isolates were the most related pair, having similar patterns and the highest similarity coefficients. The study implies that human cases in Egypt are of the camel/dog strain, and camels are important hosts for the transmission of human hydatidosis.

Association of some HLA-DRB1 antigens with Echinococcus granulosus specific humoral immune response.

An ELISA system using crude camel hydatid fluid antigen was used to detect specific IgG and IgG1 in sera of 35 cystic echinococcosis (CE) patients in whom the distribution of class II HLA-DR3 and HLA-DR11 was determined. The recorded sensitivities were 88.6 % and 94.35 % for IgG and IgG1 respectively. In patients with high humoral immune response a statistically highly significant increased frequency of HLA-DR3 (P<0.01) was recorded for IgG with high relative risk value (RR=3.2) and reasonable etiologic fraction (EF=0.3), while HLA-DR11 recorded P<0.05, RR=2.6, & EF=0.2. For IgG1 both antigens showed significant increased frequency (P<0.05), RR (2.95 & 2.79 respectively), EF (0.28 & 0.23 respectively). HLA-DR3 was highly significantly associated with complicated cases (P<0.01, RR=4.36, EF=0.4) in whom the mean antibody units for both IgG and IgG1 were significantly raised (P<0.05). It is advisable to rely on IgG1 for the diagnosis of CE and to consider the genetic disposition of the patient as an important criterion in the outcome of infection.

The evaluation of HLA-DRB1 antigens as susceptibility markers for unilocular cystic echinococcosis in Egyptian patients.

This is the first study dealing with the correlation between HLA antigens and cystic echinococcosis (CE) in Egyptian patients. The potential immunogenetic predisposition for susceptibility and resistance to unilocular echinococcosis was investigated by HLA-DRB1 typing; first by HLA-DRB1 amplification using PCR then using the allele-specific probing technique based on the reverse hybridization principle. The study was carried out on 35 patients with confirmed CE, and 100 apparently healthy individuals. A statistically significant positive association was found between HLA-DR3 and HLA-DR11 and the occurrence of CE. HLA-DR3 antigen was positively associated with the occurrence of isolated pulmonary cysts, multiple cysts, cysts >5 cm in size, non-cured disease and with a common radiological picture of hydatid cyst. A significant positive association of HLA-DR11 with the occurrence of cysts <5 cm in size was detected. This study demonstrates that carriers of DR-3 and DR-11 are at high risk for CE, and that those with DR-3 are more liable to complications.

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.