Immunohistochemical detection of avian pneumovirus in formalin-fixed tissues

An immunohistochemical staining technique (IHC) was developed to detect avi an pneumovirus (APV) antigen in formalin-fixed, paraffin-embedded tissue se ctions using streptavidin-biotin immunoperoxidase staining. Samples of nasa l turbinates and infraorbital sinuses were collected from 4-week-old poults experimentally inoculated with APV and from older turkeys infected during naturally occurring outbreaks of avian pneumovirus. Tissue was fixed in 10% buffered neutral formalin, embedded in paraffin, sectioned and stained. In flammatory changes were observed microscopically in the mucosa and submucos a of the nasal turbinates and infraorbital sinuses of both experimentally i noculated poults and naturally infected birds. Viral antigen was detected b y IHC in the ciliated epithelial cells of nasal turbinates and infraorbital sinuses.