Anatomical spatial distribution of Influenza virus receptors in some poultry species raised in Egypt

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.

Immunohistochemical Expression of Synaptophysin in the Adult and Developing Cervical and Lumbar Enlargements of the Spinal Cord of Rabbit

Background: The principle findings of synaptophysin immunoreactivity (SynpIR) during the ontogeny of rabbit spinal cord are: At E14, SynpIR precedes in the entire marginal layer especially at the entrance zone of dorsal root and motor neurite outgrowth emerged from the basal plate. At E21, SynpIR is expressed in the motoneurons of ventral and lateral horns of mantle layer growing into the ventrolateral columns of marginal layer. Methods: We found intensely stained thick tracts and diffuse axons among proliferating neuroblasts of mantle layer. The peripheral parts of ventral horns were occupied with closely packed multipolar neurons from which long dendrites departed toward the surface of marginal layer. Results: At E28, pronounced SynpIR presented in the ventral grey horn while the white matter was faintly stained., meanwhile the dorsal horn was more cellular than ventral and lateral horns. Few intensively SynpIR fibers cross the dorsal and ventral commissures. In adult, profuse SynpIR appeared in the entire grey matter, and stained dendrites departed from neurons in the lateral laminae into the adjacent funiculi as finger-like projections. These projections did not reach the surface, so that the outer one-third to onefourth of the funiculi contained little or no SynpIR. In the periphery of ventral horns, we found large multipolar neurons with faintly stained cytoplasm. The white matter and the neuroepithelial cells surrounding the central canal were almost unstained. Conclusion: Synaptophysinis a reliable marker for fiber outgrowth and synapse formation in therabbit spinal cord, and its differential expression levels is specific and almost completed before birth.

Comparative studies on chick embryo cell rabies vaccine and human diploid cell vaccine: pre-exposure use and purity of the vaccines.

Neutralizing antibody responses to commercial Japanese-produced chick embryo cell (CEC) vaccines in Japanese and to commercial human diploid cell rabies vaccines (HDCV) in Filipinos were compared by the rapid fluorescent focus inhibition test (RFFIT). Neutralizing antibody titers of the Japanese after subcutaneous (sc) immunization with two doses of the CEC vaccines were not lower than those of the Filipinos with two or three doses of HDCV by intramuscular (i.m.) or intradermal (i.d.) route, respectively. Protein nitrogen content of the CEC vaccine was about 1/300th that of the HDCV. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting analysis showed that non-viral protein content in the CEC vaccine was much lower than that in the HDCV. The CEC rabies vaccine seems to be as safe and effective as the HDCV for human pre-exposure immunization.