Immune response to respiratory syncytial virus infection (<i>Orthopneumovirus</i>)

Abstract

Respiratory syncytial virus (RSV) infects children as well as elderly and immunocompromised subjects. In 2016, RSV was renamed to Orthopneumovirus owing to virus taxonomy latinization and was also included into the Pneumoviridae family. However, in this review we will use the old and more common RSV name. RSV infection may occur throughout human lifetime as it does not induce sterilizing immunity. During RSV infection, diverse immune cells such as dendritic cells, macrophages, T cells, B cells and eosinophils are involved in the antiviral response. Some of them play an important role in eliminating RSV, while the others can provoke tissue damage. An interaction between these cells occurs through the induced cytokines and chemokines, some of which emerge at early disease stages, whereas the others — at later stages. In addition, the mentioned cells can affect the course of both primary and secondary RSV infection. A prolonged or persistent RSV infection is observed in children with T-cell immunodeficiency, emphasizing the importance of T cells in resolution of acute infection as well as for virus-specific immunological memory development. Almost all the adults and children bear RSV-specific antibodies, but that doesn't protect against the repeated infection. It was shown that high mucosal rather than serum IgG level correlated better with reduced RSV load. A growing body of RSV vaccine candidates has emerged: live-attenuated, protein-based, whole-inactivated, particle-based, subunit antigens, and nucleic acid-based vaccines. While developing vaccines, there should be taken into consideration features of anti-RSV immune response as well as age of subjects to be vaccinated. In particular, to avoid vaccine-associated aggravation of RSV infection it is justified to use live attenuated vaccines in children, whereas middle-aged and the elderly subjects might be applied with subunit vaccines. Currently, no licensed vaccine for RSV infection is available. In this review, we will detail an interaction of the RSV with diverse immune cells as well as our contemporary understanding regarding preventive vaccines in RSV infection.