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.

Evaluation of an IgG cystatin capture enzyme-linked immunosorbent assay for the detection of anti-cysteine proteinase antibodies in asymptomatic trichomoniasis patients.

All isolates of T. vaginalis release cysteine proteinases proteolytic enzymes that are shed into the vagina or culture medium. Cystatin has been used successfully as a capture agent in ELISA to detect cysteine proteinase antibodies without the need for purified proteinases. The ELISA was evaluated in comparison to wet mount microscopy and culture techniques. IgG cystatin capture ELISA proved to be a sensitive and highly specific (100%) assay that could rapidly detect anti-cysteine proteinase antibodies in both vaginal washouts and sera of asymptomatic patients with a sensitivity of 100% and 86.7%, respectively. A defined discrimination between sero-positive and sero-negative individuals was markedly observed for ELISA-vaginal washouts providing a more conclusive diagnosis by this technique. The results demonstrated that in trichomoniasis patients (52 cases) whether symptomatic or asymptomatic. T. vaginalis infection was detected in 19 (36.5%), 49 (94.2%), 50 (96.1%) and 48 (92.3%) by wet mount, culture, cystatin capture ELISA-vaginal washouts and ELISA-sera, respectively. The assay was reliable also as a test of cure with a specificity of 94.4% in the vaginal washouts and 83.3% in sera.

Role of endothelial cell adhesion molecules in the development of allergy in human fascioliasis.

The recent understanding of the key role of adhesion molecules in the pathogenesis of chest allergy in parasitic infections may provide a pharmacological target for the associated asthmatic symptoms. Circulating levels of the endothelial cell adhesion molecules (CAMs): sICAM-1, sVCAM-1 and sE-selectin in sera of 18 allergic asthmatic patients. 16 fascioliasis cases (acute & chronic), 24 fascioliasis cases with allergic chest manifestations and 10 apparently healthy control subjects were estimated by ELISA method. Also, IL-4 serum level was evaluated in all groups. Chest allergy in association with fascioliasis included mainly bronchial asthma, beside eosinophilic bronchitis, persistent wheezing and chronic cough. The study provided evidence that adhesion molecules expression is up regulated in acute and chronic fascioliasis cases with allergic chest manifestations. sVCAM-1 seemed to be an early indicator of asthma development in human fascioliasis. IL-4 cytokine was suggested to be responsible for the increased expression especially in the chronic phase of the disease, yet the role of other cytokines cannot be excluded.