In Vitro Investigation of the Interaction of Avian Metapneumovirus and Newcastle Disease Virus with Turkey Respiratory and Reproductive Tissue

Abstract

In poultry, several respiratory viral infections lead to a drop in egg production associated with high economic losses. While the virus–host interactions at the respiratory epithelium are well studied, less is known about these interactions in the oviduct. To investigate possible differences between virus infections at these epithelial structures, we compared the interactions of two important poultry viruses on turkey organ cultures. Two members of the order Mononegavirales, the Avian Metapneumovirus (AMPV) and the Newcastle disease virus (NDV), were selected to conduct the in vitro experiments since these viruses can infect both the trachea and oviduct. In addition, we used different strains of these viruses, a subtype A and a subtype B strain for AMPV and the NDV strains Komarow and Herts’33, to detect possible differences not only between the tissues but also between different viral strains. Turkey tracheal and oviduct organ cultures (TOC and OOC) were prepared to investigate viral replication, antigen localisation, lesion development, and the expression pattern of interferon-λ and importin-α isoforms. All viruses replicated more efficiently in the oviduct than in the tracheal epithelium (p < 0.05). In addition, we observed higher expression levels of both, IFN-λ and importin-α in OOCs compared to TOCs. Our results indicated strain-dependent differences, with the AMPV-B- and Herts’33 strains being more virulent in organ cultures than the AMPV-A- and Komarow strains, based on the higher viral genome loads, more severe histological lesions, and higher upregulation of IFN-λ. Overall, our findings reveal tissue- and virus strain-dependent differences, which may have consequences for disease development in the host tissue and, subsequently, possible treatment strategies.

Effects of G and SH Truncation on the Replication, Virulence, and Immunogenicity of Avian Metapneumovirus

“…The aMPV strain SNU21004, belonging to subtype B of aMPV, was used in this study. The SNU21004 virus was isolated from the nasal cavity of a dead bird (37 days old) with respiratory diseases on a layer chicken farm in Korea in 2021 and propagated in a chicken embryo tracheal organ culture (TOC) with a 1:1 mixture of Medium-199 and Ham F10 in 15 mL culture tubes in a 37 °C shaking incubator, as previously described [ 19 , 20 ]. The propagated virus was finally passaged eight times in TOC and finally stored at −80 °C until use.…”

Pathological and phylogenetic characteristics of fowl AOAV-1 and H5 isolated from naturally infected Meleagris Gallopavo

“…Several pathogens are known that affect the respiratory system of turkeys for example, avian influenza virus (AIV) [5], avian paramyxovirus [6], metapneumovirus [7], adenovirus [8], Bordetella bronchiseptica [9] and Mycoplasma gallisepticum [10]. Mixed infections have also been recorded [4,11].…”