Patterns of alveolar macrophage activation upon attenuated and virulent African swine fever viruses in vitro

• Published in: Comparative immunology, microbiology and infectious diseases Vol. 72; p. 101513
• Main Authors: Tatoyan, Marina R., Izmailyan, Roza A., Semerjyan, Anna B., Karalyan, Naira Yu, Sahakyan, Carmen T., Mkrtchyan, Gayane L., Ghazaryan, Hovsep K., Arzumanyan, Hranush H., Semerjyan, Zara B., Karalova, Elena M., Karalyan, Zaven A.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.10.2020
• Subjects: African Swine Fever - immunology; African swine fever virus; African Swine Fever Virus - pathogenicity; Alveolar macrophage activation; Animals; M1 polarization; Macrophage Activation; Macrophages, Alveolar - immunology; Swine; Virulence; Alveolar macrophage activation; African swine fever virus; M1 polarization
• ISSN: 0147-9571; 1878-1667
• DOI: 10.1016/j.cimid.2020.101513

•Activation pattern of AM induced by ASFV-Georgia2007 differs from LPS/IFN-gamma BA71V mediated activation.•The antiviral response of porcine AM infected with an ASFV-BA71V is more related to those stimulated with LPS/IFN-gamma. The pattern of porcine alveolar macrophage (AM) activation upon classical stimuli of two strains of African swine fever (ASF) viruses, an attenuated ASFV-BA71V and virulent ASFV-Georgia2007 were investigated. In an in vitro experiment ASFV-Georgia2007-infected AM showed M1 polarization pattern different from the one induced by classical stimuli. Altered morphology, appearance of binuclear cells, decreased synthesis of IFN-alpha as well as IFN-epsilon was observed compared with attenuated ASFV-BA71V, and decreased synthesis of IFN-omega compared with intact cells. However, CD68 level did not significantly differ between alveolar macrophage populations infected by ASFV-Georgia2007 and control group, while both LPS/IFN-gamma stimulation and non-pathogenic ASFV-BA71V virus increased the level of CD68 soluble receptor. AM infection with ASFV-Georgia2007 resulted in remarkable DNA proliferation whereas LPS/IFN-gamma and ASFV-BA71V induced less expressed DNA proliferation in activated cells. The higher value of nitric oxide was obvious in the cells infected with ASFV-BA71V, compared to ASFV-Georgia2007 and LPS/IFN-gamma activated cells. In conclusion, pattern of activation of alveolar macrophages induced by ASFV-Georgia2007 virus differs from the one expressed in LPS/IFN-gamma- and ASFV-BA71V-activated cells. ASFV-BA71V and LPS/IFN-gamma share similar antiviral response of porcine AM. Therefore we assume that wild type virulent ASFV can partially down regulate antiviral response of AM and conclude that evolutionary decrease of virulence in ASFV is related to alterations of control of the host cell antiviral response.