2782. Host Immune Response to Enterovirus and Parechovirus Systemic Infections in Children

BACKGROUND: Enterovirus (EV) and human Parechovirus (PeV) cause a range of illness including asymptomatic to systemic infections. The host immune response in children, especially the one induced by PeV, is largely unknown. The aim of this study was to determine the immune response induced by EV and PeV in cerebrospinal fluid (CSF) and plasma obtained from children with systemic infection. METHODS: Left-over CSF and paired blood samples collected from children with laboratory confirmed EV and PeV central nervous system-infection were enrolled in this study. EV/PeV-negative CSF and paired plasma from children was used as controls. Level of cytokines and chemokines were measured using a customized 21-plex ELISA panel that included 16 cytokines and 5 chemokines (Millipore, CA). Additionally, clinical characteristics of all the patients were collected to determine the potential association between the immune response and pathogenicity. RESULTS: Total of 74 samples were enrolled and divided into 3 groups, EV (n = 27), PeV (n = 23) and control group (n = 24). Median age of all the three groups was 2 weeks (IQR 2–4 weeks).The key analytes which had a significant difference between each groups are show in the Table. In general, EV induced more robust cytokine secretion than PeV and control group. Anti-viral response such as IFN-g was remarkably absent in both CSF and plasma in PeV group compared with EV group (P < 0.05). Only IL-8 was significantly higher (P < 0.05) in EV CSF group compared with any other groups or sample types. Level of all the chemokines measured were much higher in all the three groups but significant difference was found between PeV CSF and plasma for IP-10 and MCP-1 chemokines (P < 0.05). CONCLUSION: In this study, we demonstrate that EV and PeV induces distinct immune response in children with systemic infections. While EV induces more robust inflammation, PeV-induced inflammation appears to be either weak or absent in CSF, but robust in plasma. The suppressed pro-inflammatory response might facilitate PeV growth and proliferation in CSF and might play a role in disease severity. Further studies are needed to fully understand the differential immune response induced by these two viruses. [Image: see text] DISCLOSURES: All authors: No reported disclosures.