Profiling of circulating immune factors and host-derived extracellular vesicles in response to bacterial or malaria acute fever

Background: The misdiagnosis of acute febrile illness (AFI) aetiology is associated with antibiotic overuse and improper patient management. To develop novel strategies, a more comprehensive understanding of the pathophysiological mechanisms underlying the early response to different causes of fever is essential. Methods: We examined the host response to AFI, through the retrospective investigation of serum samples from febrile patients with bacterial infection (n=52) or malaria (n=73). The systemic levels of CXCL10, IFNγ, IL-2, IL-4, IL-6, IL-8, procalcitonin (PCT), TRAIL, ICAM-1, VCAM-1, osteopontin, TNFα, MMP-2 and MMP-9 were measured by multiplex immunoassays, while the relative abundance of 37 different surface markers of circulating extracellular vesicles (EVs) was determined using the MACSplex kit (Miltenyi Biotec).