Encephalomyelitis, Equine

Subject Index

Infections Caused by SARS: Main Characteristics, Targets and Inhibitors

SARS-coronavirus (SARS-CoV) originated in China from 2002 to 2003 and caused a global outbreak with 8098 cases and 774 confirmed deaths. More than 15 years later, in less than a year, the new coronavirus (2019-nCoV) has infected more than 44 million people and killed more than 1 million. The COVID-19 pandemic has brought serious consequences for several countries and a worldwide alert about coronaviruses. Severe acute respiratory syndrome (SARS) is an emerging infectious viral disease characterized by severe clinical manifestations of the lower respiratory tract that lead to severe lung damage and the spread of the virus to several other organs. Phylogenetic analyzes demonstrate that SARS-CoV-2 shares a 79% identity with SARS-CoV, and just as there was no effective treatment against SARS-CoV, it does not yet exist against SARS-CoV-2. However, researchers from all over the world are dedicating themselves to several studies in an attempt to find the best treatment and prevention against the coronavirus. Thus, this book chapter addresses the main characteristics of SARS, the main targets and drugs that have achieved excellent results in clinical trials.

Index

Part J: Placental Interferons, Implantation and Pregnancy

Interferons have antiviral, antiproliferative and immunomodulatory effects on immune responses to defend the body against viral infections and malignant cells. The type I interferon family includes interferons alpha (IFNA1-IFNA10, IFNA13, IFNA14, IFNA16, IFNA17 and IFNA21), interferon beta (IFNB), interferon delta (IFND), interferon epsilon (IFNE), interferon kappa (IFNK), interferon tau (IFNT) and interferon omega (IFNW1-IFNW3). Interferon gamma (IFNG) is the only known type II interferon. Of the type I interferons, IFNT is expressed by mononuclear trophectoderm cells of ruminant conceptuses and IFND is expressed by equine and porcine conceptuses to affect pregnancy recognition and the uterine environment at the peri-implantation stage.

The pig conceptus also secretes IFNG during the peri-implantation period, but its role is not known. It is clear that interferons secreted by conceptus trophectoderm and/or immune cells recruited to the site of implantation of blastocysts during early pregnancy affect mechanisms for establishing the window of implantation as well as uterine acceptance of the conceptus, and placentation in many, if not all, species of mammals. This conserved trait of the mammalian peri-implantation period involves secretion of type I and/or a type II IFNs by trophectoderm cells which induces and/or enhances the expression of interferon stimulated genes in a cell-specific (spatial) fashion. Ruminant IFNT is the sole interferon so far identified as a signal of early pregnancy. But interferons produced by the conceptus or uterine immune cells of other species likely affect the peri-implantation uterus as well as endometrial decidualisation, and placental growth and development critical to successful outcomes of pregnancy. This review will highlight current knowledge of interferons that may affect pregnancy outcomes in humans, domestic animals and rodents.

Sialic Acid Recognition, Removal and Surface Presentation: Role in Microbial Pathogenesis of Human Hosts

Sialic acids (Sia) play a role in the survival of microbes within the diverse environments that both pathogenic and non-pathogenic microbes inhabit. 3-Deoxy-Dmanno- oct-2-ulosonic acid (KDO) and 2-keto-3-deoxynononic acid (KDN) are crucial for the survival of almost all bacterial species, while other Sia are a favourite target for viruses and other host adapted pathogens when interacting with host tissues that are required for survival/replication of the microbe. All pathogenic microbes, whether bacteria, viruses, parasites, or fungi, must be able to specifically interact with host cells/tissues to initiate disease. The success of these pathogens at maintaining a disease state relies on the ability of these organisms to subvert or evade the host immune responses. In this chapter we will discuss the ways in which Sia, Neu5Ac specifically, is crucial for the ability for many human pathogens to cause and maintain disease.