Concurrent infection with porcine reproductive and respiratory syndrome virus and Haemophilus parasuis in two types of porcine macrophages: apoptosis, production of ROS and formation of multinucleated giant cells

Abstract

Porcine reproductive and respiratory syndrome (PRRS) is one of the most significant and economically important infectious diseases affecting swine worldwide and can predispose pigs to secondary bacterial infections caused by, e.g. Haemophilus parasuis. The aim of the presented study was to compare susceptibility of two different types of macrophages which could be in contact with both pathogens during infection with PRRS virus (PRRSV) and in co-infection with H. parasuis. Alveolar macrophages (PAMs) as resident cells provide one of the first lines of defence against microbes invading lung tissue. On the other hand, monocyte derived macrophages (MDMs) represent inflammatory cells accumulating at the site of inflammation. While PAMs were relatively resistant to cytopathogenic effect caused by PRRSV, MDMs were much more sensitive to PRRSV infection. MDMs infected with PRRSV increased expression of pro-apoptotic Bad, Bax and p53 mRNA. Increased mortality of MDMs may be also related to a higher intensity of ROS production after infection with PRRSV. In addition, MDMs (but not PAMs) infected with H. parasuis alone formed multinucleated giant cells (MGC); these cells were not observed in MDMs infected with both pathogens. Higher sensitivity of MDMs to PRRSV infection, which is associated with limited MDMs survival and restriction of MGC formation, could contribute to the development of multifactorial respiratory disease of swine.Electronic supplementary materialThe online version of this article (doi:10.1186/s13567-017-0433-6) contains supplementary material, which is available to authorized users.

The Role of Antibodies Against the Crude Capsular Extract in the Immune Response of Porcine Alveolar Macrophages to In Vitro Infection of Various Serovars of Glaesserella (Haemophilus) parasuis

“…The luminol-amplified chemiluminescence is able to detect superoxide anion as well as hydrogen peroxide in the presence of peroxidases ( 28 ). Because decomposition of these reactive oxygen species is catalyzed by the superoxide dismutase and catalase, these two enzymes apparently play an important role in the oxidative stress resistance of G. parasuis observed in our study as well as by other authors ( 20 , 29 , 30 ). Moreover, catalase was identified among the secreted proteins of G. parasuis Nagasaki strain as immunoreactive with G. parasuis anti-Nagasaki convalescent sera ( 31 ).…”

“…Production of reactive oxygen species (ROS) by in vitro infected PAMs was measured using chemiluminescence (CL) assay ( 20 ). After overnight incubation of PAMs in 96-well plates (37°C, 5% CO 2 ), the wells were washed with Hanks’ balanced salt solution (HBSS, Lonza) and luminol-derivative L-012 (Wako Chemicals GmbH) was added to amplify the CL induced by respiratory burst of stimulated PAMs.…”

Postweaning mortality in commercial swine production II: review of infectious contributing factors

“…This diverse organism is a common inhabitant of the nasopharyx ( Smart et al, 1989 ; Choi et al, 2003 ; MacInnes et al, 2008 ; USDA, 2016 ) but, when sepsis occurs, presents with clinical signs similar to signs observed with S. suis . Like S. suis , G. parasuis may interact with PRRSV to contribute to PRDC ( Kavanova et al, 2017 ), although clear evidence of such an interaction was not observed by Solano et al (1997) . Vaccination of sows with an autogenous G. parasuis vaccine has been shown to reduce offspring nursery mortality (1.4–2.1% monthly mortality for control vs. 0.5–0.9% monthly mortality for vaccinated; McOrist et al, 2009 ).…”

Fighting Cancer with Mathematics and Viruses

“…These models only allowed budding as a mechanism for viral particle production from syncytia, assuming that no apoptosis occurs from fused cells [ 158 ]. Recent reports suggest that this may not be the case [ 159 , 160 , 161 , 162 , 163 , 164 , 165 ], depending on the virus; adjustments during model development and fitting can resolve such issues. In their model, Jacobsen and Pilyugin found that an increase in burst size would allow for tumor control.…”