Serum-Derived Extracellular Vesicles from African Swine Fever Virus-Infected Pigs Selectively Recruit Viral and Porcine Proteins

Abstract

African swine fever is a devastating hemorrhagic infectious disease, which affects domestic and wild swines (Sus scrofa) of all breeds and ages, with a high lethality of up to 90–100% in naïve animals. The causative agent, African swine fever virus (ASFV), is a large and complex double-stranded DNA arbovirus which is currently spreading worldwide, with serious socioeconomic consequences. There is no treatment or effective vaccine commercially available, and most of the current research is focused on attenuated viral models, with limited success so far. Thus, new strategies are under investigation. Extracellular vesicles (EVs) have proven to be a promising new vaccination platform for veterinary diseases in situations in which conventional approaches have not been completely successful. Here, serum extracellular vesicles from infected pigs using two different ASFV viruses (OURT 88/3 and Benin ΔMGF), corresponding to a naturally attenuated virus and a deletion mutant, respectively, were characterized in order to determine possible differences in the content of swine and viral proteins in EV-enriched fractions. Firstly, EVs were characterized by their CD5, CD63, CD81 and CD163 surface expression. Secondly, ASFV proteins were detected on the surface of EVs from ASFV-infected pig serum. Finally, proteomic analysis revealed few specific proteins from ASFV in the EVs, but 942 swine proteins were detected in all EV preparations (negative controls, and OURT 88/3 and Benin ΔMGF-infected preparations). However, in samples from OURT 88/3-infected animals, only a small number of proteins were differentially identified compared to control uninfected animals. Fifty-six swine proteins (Group Benin) and seven proteins (Group OURT 88/3) were differentially detected on EVs when compared to the EV control group. Most of these were related to coagulation cascades. The results presented here could contribute to a better understanding of ASFV pathogenesis and immune/protective responses in the host.

Preparation of Monoclonal Antibodies against the Viral p54 Protein and a Blocking ELISA for Detection of the Antibody against African Swine Fever Virus

“…Therefore, screening of the infected animals as early as possible is of great significance for ASF prevention and control. As clinical symptoms of ASFV-infected animals vary considerably from acute forms with a mortality rate of 90-100% in domestic pigs and wild boar to subclinical infections in bushpigs and warthogs [28], and the clinical symptoms between ASF and classical swine fever infection demonstrate no significant differences [29], more accurate laboratory detection methods are required to determine the infection of animals.…”

Exosomes from COVID-19 Patients Carry Tenascin-C and Fibrinogen-β in Triggering Inflammatory Signals in Cells of Distant Organ

“…Elevated FGB expression was reported in lung adenocarcinoma, suggesting a potential role as a biomarker [ 26 ]. Elevated fibrinogen is detected in exosomes from drug- and alcohol-induced liver injury, neurological disorder, and swine flu viral infection [ 14 , 27 , 28 , 29 , 30 ].…”

Exosomes from COVID-19 patients carry tenascin-C and fibrinogen-β in triggering inflammatory signals in distant organ cells

“…Elevated FGB expression was reported in lung adenocarcinoma and suggested a potential role as biomarker (26). Elevated fibrinogen is detected in exosomes from drug and alcohol induced liver injury, neurological disorder, and swine flu viral infection (14, 27–30).…”