Localization of 9-O-Acetylated Sialic Acids in Bovine Respiratory and Gastrointestinal Tract using Influenza D HEF Protein

Abstract

Influenza D is a recently discovered virus, first collected in April of 2011 from nasal swabs of swine. It was soon discovered that the natural hosts of the virus were cattle, a species that is not susceptible to other subtypes of Influenza. Influenza D is closely related to Influenza C,both using the HEF-protein for attachment, in contrast to the HA protein Influenza A and Influenza B possess. The receptor the virus needs to enter the cell are 9-O-Acytelated Sialic Acids. To study the localization of the receptor of this new virus tissue micro arrays (TMAs) were made from the bovine respiratory tract and the bovine gastrointestinal tract. The initial attempts to produce HEF recombinantly were unsuccessful. Though unable to use IDV HEF to localize its receptor 9-O-Acetylated Sialic Acids, lectin stainings developed for Influenza A have been performed on the produced TMAs to visualize sialic acid presence. In performed lectin stainings mucus in both the bovine respiratory as gastrointestinal tract was found to contain contain 2,3- linked and 2,6-linked sialic acids. One of the liver sections tested positive for 2,6-linked sialic acids. A staining with an H1 Influenza A virus showed no attachment to bovine respiratory epithelium.