Genetic and antigenic diversity of African swine fever virus

Abstract

Highlights ASFV demonstrates extreme genetic diversity and use multiple mechanisms for acquisition novel phenotype characteristics  Evolutionary rate of ASFV variable regions may approach similar values to RNA viruses  More complete ASFV sequences are needed to better understand viral genome plasticity, antigenic diversity, and evolution  Heamdsorbtion inhibition assay is a reliable tool in defining ASFV antigenic diversity and candidate vaccine efficiency ABSTRACT African swine fever virus ( ASFV) is the only known DNA arbovirus, and the ability to replicate efficiently in both insect and mammalian cells is encoded in its viral genome.Despite having a relatively low overall genomic mutation rate, ASFV demonstrates genetic diversity in certain genes and complexity in gene content in other genomic regions, indicating that ASFV may exploit multiple mechanisms for diversification and acquire new phenotype characteristics. ASFV antigenic diversity is reflected in the ability to type cross-protective viruses together into serogroups, largely based on antibody-mediated inhibition of hemadsorption. Here we review ASFV genetic signatures of ASFV type specificity, genome variability, and the hemadsorption as a means of defining virus antigenic type, and how these may be used toward defining antigenic and phenotypic diversity that is problematic for development of vaccine solutions to ASF.ASFV causes explosive transboundary epidemics of ASF. In recent years, ASF has spread dramatically and now poses a threat to swine production worldwide (Cisek et al.,

Complete genome analysis of African swine fever virus responsible for outbreaks in domestic pigs in 2018 in Burundi and 2019 in Malawi

“…The protein pEP402R, a homologue of the T-lymphocyte surface antigen CD2, encoded by the EP402R gene is located in the lipoprotein membrane of the outer viral envelope and plays an important role in the adhesion of erythrocytes to infected cells (hemadsorption) and the binding of the ASFV particles to host erythrocytes during infection (Alejo et al 2018 ; Dixon et al 2019 ). This gene has been used to define eight viral antigenic types called serogroups (Malogolovkin and Kolbasov 2019 ). The results of the present study showed that the BUR/18/Rutana and MAL/19/Karonga ASFV strains may share the hemadsorption properties with ASFV strains belonging to serogroups 7 and 8, respectively (Fig.…”

Role of the DNA-Binding Protein pA104R in ASFV Genome Packaging and as a Novel Target for Vaccine and Drug Development

“…Despite having a relatively low overall genomic mutation rate, the evolutionary rate of the ASFV variable regions seems to approach those of RNA viruses and can greatly affect ASFV genome structure [25,26]. ASFV strains showing MGFs gene duplication are often associated with a more violent phenotype while attenuating loss of MGFs occurs after viral passage in in vitro cell culture [22,26,27].…”

“…Despite having a relatively low overall genomic mutation rate, the evolutionary rate of the ASFV variable regions seems to approach those of RNA viruses and can greatly affect ASFV genome structure [25,26]. ASFV strains showing MGFs gene duplication are often associated with a more violent phenotype while attenuating loss of MGFs occurs after viral passage in in vitro cell culture [22,26,27]. Comparative genomic analyses have also identified a range of genes in the constant region undergoing positive selection (e.g., CD2v/EP402R and C-type lectin/EP153R) that represent another source of genetic diversity among ASFV isolates [5,26,28].…”

“…ASFV strains showing MGFs gene duplication are often associated with a more violent phenotype while attenuating loss of MGFs occurs after viral passage in in vitro cell culture [22,26,27]. Comparative genomic analyses have also identified a range of genes in the constant region undergoing positive selection (e.g., CD2v/EP402R and C-type lectin/EP153R) that represent another source of genetic diversity among ASFV isolates [5,26,28]. These evolutionary processes are of considerable interest as they are key drivers of change in specific genes and encoded antigens, arguably influencing vaccination strategies and/or the stability of live attenuated vaccines, as well as diversity in host response.…”

A visual on‐site method for African swine fever virus detection in raw pig tissues

“…Moreover, the epidemic has a tendency to spread rapidly around the world (Zhou et al, 2018), so there is an urgent need for an effective method to control the spread of ASF. Although its pathogenesis and modes of transmission are known to some extent (Arias, Jurado, Gallardo, Fernández‐Pinero, & Sánchez‐Vizcaíno, 2018; Dixon, Sun, & Roberts, 2019), the effective ASF vaccine and medicine have not yet been developed, due to the complex structure of ASFV (Malogolovkin & Kolbasov, 2019; Sánchez, Pérez‐Núñez, & Revilla, 2019; Sánchez‐Cordón, Montoya, Reis, & Dixon, 2018; Sánchez‐Vizcaíno, Mur, & Martínez‐López, 2012; Sunwoo et al, 2019). Therefore, the detection of ASFV is essential for pork industry food safety and disease prevention and control worldwide.…”