Immune Response Modulation by Caliciviruses

Abstract

Noroviruses and Sapoviruses, classified in the Caliciviridae family, are small positive-stranded RNA viruses, considered nowadays the leading cause of acute gastroenteritis globally in both children and adults. Although most noroviruses have been associated with gastrointestinal disease in humans, almost 50 years after its discovery, there is still a lack of comprehensive evidence regarding its biology and pathogenesis mainly because they can be neither conveniently grown in cultured cells nor propagated in animal models. However, other members of this family such as Feline calicivirus (FCV), Murine norovirus (MNV), Rabbit hemorrhagic disease virus (RHDV), and Porcine sapovirus (PS), from which there are accessible propagation systems, have been useful to study the calicivirus replication strategies. Using cell cultures and animal models, many of the functions of the viral proteins in the viral replication cycles have been well-characterized. Moreover, evidence of the role of viral proteins from different members of the family in the establishment of infection has been generated and the mechanism of their immunopathogenesis begins to be understood. In this review, we discuss different aspects of how caliciviruses are implicated in membrane rearrangements, apoptosis, and evasion of the immune responses, highlighting some of the pathogenic mechanisms triggered by different members of the Caliciviridae family.

Intra- and Cross-Species Transmission of Astroviruses

“…How AstVs are able to evade type I IFN activation is currently unknown. Other non-enveloped, positive-sense RNA viruses such as caliciviruses utilize viral proteins to suppress IFN mRNA production and IRF-3 activation in order to evade the host innate immune response [103]. The ALI model can be utilized to explore what AstVs viral protein(s) to inhibit innate immune activation.…”

Immunity against Lagovirus europaeus and the Impact of the Immunological Studies on Vaccination

“…However, in the ‘battle for survival’ between viral pathogens and vertebrate hosts, this response is often counteracted by viral proteins which are able to block the intracellular processing and presentation machinery in DC at different stages [ 161 ].…”

“…Calicivirus infections in vertebrate hosts most widely trigger a humoral response, which is involved in infection control through the limitation of virus propagation and the systemic spread of the virus [ 121 , 161 , 168 , 169 ]. In rabbits, after RHDV infection, the antibody response is different either between naïve and immune rabbits (survivors of infection or after vaccination), and between juveniles with mostly immature B-cells and adults with a fully mature immune system [ 6 , 111 , 128 ].…”

Serological Humoral Immunity Following Natural Infection of Children with High Burden Gastrointestinal Viruses

“…However, it is not known if serum antibody is the most important correlate of protection against sapovirus or whether it simply mirrors the antibody levels on the intestinal mucosa. As the small intestinal mucosa is the location of infection, it is presumed that fecal IgA antibodies are important to immune protection and that innate immune activation against viral infection is mediated through the interferon pathway [235]. Chronic sapovirus infections in individuals with immunodeficiencies show that clearance of infections depends on intact host immune responses [216,236].…”