Contribution of Cytokines to Tissue Damage During Human Respiratory Syncytial Virus Infection

Younger than 2 years old children affected with acute respiratory tract infections (ARTIs) caused by human respiratory syncytial virus (hRSV) world widely. In every year, a lot of hRSV-induced bronchitis & pneumonic patients are hospitalized during winter season. To prevent hRSV infection induced health and economic burden, there are no available vaccine in market. Pathology of hRSV is significant damage of pulmonary epithelium due to excessive inflammatory response at the airways. Cytokines can be beneficial or harmful for the host but they play a major role to establishment and modulation of the immune and inflammatory responses. The harmful effect detected in hRSV infection is tissue damage caused by aggregation of immune cell on the site of infection. Placing of Inflammatory cells are depends on, quantity of cytokines such as IL-1, IL-6, IL-10, and CCL5 are increased, while IL-10 and IFN-γ are decreased. Although, further studies are needed to draw out what are directly involved mediators associated with hRSV damage entirely. However, another report indicating that this virus not only affected respiratory tract but also affected central nervous system (CNS). A published report mentioned that highest levels of IL-6, IL-8 (CXCL8), CCL2, and CCL4 have been reported in cerebrospinal fluid from patients with severe bronchiolitis and hRSV-associated encephalopathy. In that review article, researcher provided the role of cytokines, secreted during hRSV infection and their potentially harmful contribution to tissue damage of the respiratory tract and the CNS.
(RA)