A Semiquantitative Scoring System for Histopathological and Immunohistochemical Assessment of Lesions and Tissue Tropism in Avian Influenza
Open Access
- 9 May 2021
- Vol. 13 (5), 868
- https://doi.org/10.3390/v13050868
Abstract
The main findings of the post-mortem examination of poultry infected with highly pathogenic avian influenza viruses (HPAIV) include necrotizing inflammation and viral antigen in multiple organs. The lesion profile displays marked variability, depending on viral subtype, strain, and host species. Therefore, in this study, a semiquantitative scoring system was developed to compare histopathological findings across a wide range of study conditions. Briefly, the severity of necrotizing lesions in brain, heart, lung, liver, kidney, pancreas, and/or lymphocytic depletion in the spleen is scored on an ordinal four-step scale (0 = unchanged, 1 = mild, 2 = moderate, 3 = severe), and the distribution of the viral antigen in parenchymal and endothelial cells is evaluated on a four-step scale (0 = none, 1 = focal, 2 = multifocal, 3 = diffuse). These scores are used for a meta-analysis of experimental infections with H7N7 and H5N8 (clade 2.3.4.4b) HPAIV in chickens, turkeys, and ducks. The meta-analysis highlights the rather unique endotheliotropism of these HPAIV in chickens and a more severe necrotizing encephalitis in H7N7-HPAIV-infected turkeys. In conclusion, the proposed scoring system can be used to condensate HPAIV-typical pathohistological findings into semiquantitative data, thus enabling systematic phenotyping of virus strains and their tissue tropism.Keywords
Funding Information
- European Social Fund (100380880)
This publication has 73 references indexed in Scilit:
- Multiparametric and semiquantitative scoring systems for the evaluation of mouse model histopathology - a systematic reviewBMC Veterinary Research, 2013
- Effect of species, breed and route of virus inoculation on the pathogenicity of H5N1 highly pathogenic influenza (HPAI) viruses in domestic ducksVeterinary Research, 2013
- Neuropathogenesis of a highly pathogenic avian influenza virus (H7N1) in experimentally infected chickensVeterinary Research, 2011
- The Pattern of Influenza Virus Attachment Varies among Wild Bird SpeciesPLOS ONE, 2011
- Antigenic Drift in H5N1 Avian Influenza Virus in Poultry Is Driven by Mutations in Major Antigenic Sites of the Hemagglutinin Molecule Analogous to Those for Human Influenza VirusJournal of Virology, 2011
- Theory of sampling and its application in tissue based diagnosisDiagnostic Pathology, 2009
- Pathogenicity of Highly Pathogenic Avian Influenza Virus (H5N1) in Adult Mute SwansEmerging Infectious Diseases, 2008
- Experimental Infection of Swans and Geese with Highly Pathogenic Avian Influenza Virus (H5N1) of Asian LineageEmerging Infectious Diseases, 2008
- Susceptibility of Canada Geese (Branta canadensis) to Highly Pathogenic Avian Influenza Virus (H5N1)Emerging Infectious Diseases, 2007
- Susceptibility of North American Ducks and Gulls to H5N1 Highly Pathogenic Avian Influenza VirusesEmerging Infectious Diseases, 2006