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.

Demonstration of Solitary Chemosensory Cells in the Nasopalatine and Vomeronasal Ducts of Rat by α-gustducin and GAP-43 Immunohistochemistry

In the present study, we used immunohistochemistry for α - gustducin and Growth Associated Protein-43 (GAP-43) to examine the spatial distribution of the solitary chemosensory cells primarily in the nasopalatine ducts of rat at the time of weaning, which is lack in the literature. Methods: We found abundant solitary cells labeled with α- gustducin in the nasopalatine duct and vomeronasal organ of rats. In the nasopalatine duct, these cells were more frequent in the medial wall epithelium; meanwhile appreciable number of α-gustducin labeled cells were localized only in the neuroepithelium portion of the vomeronasal organ. We found the number of these cells increased toward the entries of the nasopalatine and vomeronasal ducts into the nasal cavity. We also found GAP-43 heavily expressed in the core of nasopalatine duct, close to the basement membrane and around the blood vessels and cavernous spaces of the vomeronasal organ. Results: GAP-43 labeled axons apposed the solitary chemosensory cells closely, either coursing along or wrapping the solitary chemosensory cells. Individual cells were apposed by one or a few intraepithelial nerve fibers and a single fiber sometimes contacted a few solitary chemosensory cells. Intraepithelial GAP-43 labeled fibers were more frequent toward the nasal cavity and the entry of nasopalatine and vomeronasal ducts in close association with the solitary chemosensory cells. Conclusion: We conclude that α -gustducin-expressing cells alongside the GAP-43 intraepithelial nerves in the nasopalatine and vomeronasal ducts suggests that they share the same transduction mechanisms

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.