Immunohistochemical analysis of ORF2 protein and ORF3 protein of hepatitis E virus in livers of swine in Mato Grosso state, Brazil

• Autor(a) principal: Campos,Camila G.
• Data de Publicação: 2022
• Outros Autores: Pavelegini,Lucas A.D., Pereira,Asheley H.B., Souza,Marcos A., Pescador,Caroline A.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Pesquisa Veterinária Brasileira (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-736X2022000100227
• topic: Immunohistochemistry; pORF2 HEV; protein; hepatitis E virus; liver; swine; emergent zoonosis; Brazil

ABSTRACT: Hepatitis E is an emerging zoonotic disease caused by hepatitis E virus (HEV). Immunohistochemistry (IHC) can be used to verify viral presence in human and swine livers. The aim of this study was to comparatively analyze the immunolabeling of the ORF2 protein (pORF2) versus the ORF3 protein (pORF3) of HEV in swine livers from subsistence farms in the state of Mato Grosso, Brazil. This study included 25 liver samples formalin fixed paraffin embedded tissue block from a published molecular detection and immunohistochemistry (IHC) study, which used the HEV pORF3 protein, demonstrating 4% (1/25) of positive immunolabeling and 96% (24/25) negative, in contrast to the molecular exam that showed 24% (6/25) of liver samples positive and 76% (19/25) negative. In order to increase the sensitivity of the IHC technique, these samples were analyzed using the antibody for the detection of HEV pORF2, showing 24% (6/25) immunolabeling positive and 76% (19/25) negative, equivalent to the result of molecular analysis on corresponding samples. Thus, the use of antibody to pORF2 increased the number of HEV cases detectable in the IHC by 600%. The IHC added to molecular techniques can be used as a tool for monitoring viral presence in swine livers, constituting a sensitive diagnostic methodology when liver samples fixed in formalin and embedded in paraffin are available.