ABSTRACT
Background: Avian influenza H5N1 has been distressing not only the poultry industry but also humans causing fatal infections in Egypt. Understanding the initial steps in the viral infection was proposed by many to be a key for solving the entire problem. Domestic healthy chicken, Pekin duck, Egyptian goose, Japanese quail, pigeon and turkey were purchased; three adult birds per each species. Lectin histochemistry was performed using fluorescein isothiocyanate labelled Sambucusnigra agglutinin specific for SAα2,6-gal receptors, and FITC labelled Maackiaamurensis agglutinins specific for SAα2,3-gal receptors. Methods: From each bird, three specimens per each trachea, lung, duodenum, colon, liver and brain were used. In chicken, duck, goose, Japanese quail, domestic pigeon and turkey, both SAα2,3-gal and SAα2,6-gal receptors were expressed in at least one segment of respiratory and intestinal tracts except in pigeons where SAα2,3-gal receptors were not expressed in the respiratory tract while in ducks were not expressed in lower respiratory tract and in turkey not expressed in small intestine. The human type receptors were not expressed in the lower trachea of goose, large intestine of chicken and intestinal tract and liver of turkey and pigeons. Results: The widespread detection of both SAα2,6-gal and SAα2,3-gal receptors in different tissues from each species suggests that these birds’ organs may be potential targets for both avian and human influenza viruses, and can act as adaptive host for avian influenza viruses to change receptor specificity. This may indicate that different native bird species in Egypt could have participated equally or variably in the generation of H5N1 viruses that were able to extensively infect humans. All experimental procedures were approved by Damanhour university ethics committee. The widespread detection of both SAα2,6-gal and SAα2,3-gal receptors in different tissues from each species suggests that these birds’ organs may be potential targets for both avian and human influenza viruses, and can act as adaptive host for avian influenza viruses to change receptor specificity. Conclusion: This may indicate that different native bird species in Egypt could have participated equally or variably in the generation of H5N1 viruses that were able to extensively infect humans.
ABSTRACT
Immunofluorescence assay (IFA) has been applied for detection of antibody to human immunodeficiency virus type 1 (HIV-1). To compare the IFA with an enzyme-linked immunosorbent assay (ELISA) and particle agglutination (PA), we examined the antibody response to HIV-1 in 475 sera from AIDS, PGL and ARC patients as well as several risk groups and healthy persons by three methods. The positive results by any methods were confirmed by western blot (WB). The results by all methods were well correlated on the sera from 45 asymptomatic male homosexuals and 70 female prostitutes. There were some false positive results by ELISA in the sera from prisoners and healthy persons. Four sera from drug abusers were positive only by PA and IFA and were negative by ELISA. All were WB-inconclusive. Particle agglutination and IFA results were compared with western blot analysis on 208 ELISA-positive sera. All IFA-strongly positive sera (84%) were positive by western blot. The sera with weakly positive, negative and inconclusive results by IFA (16%) were possibly any of positive, inconclusive or negative by western blot. By PA, 200 of 208 (97%) sera were PA-positive and 1% of these sera were WB-inconclusive while the PA-negative sera were either negative or inconclusive by western blot. These results suggested that PA is a simple and sensitive method for screening of HIV-1 antibody while IFA could be a primary confirmatory test and western blot would then be used for confirming any IFA-negative or inconclusive results.