IL6 and bacterial infectious disease: Of note, the fact that circulating miR-223 is independent of the presence of sepsis was further substantiated by correlation analyses revealing that serum miR-223 levels were not correlated to established markers of systemic inflammation and bacterial infection such as C-reactive protein (CRP), procalcitonin (PCT), interleukin-6 (IL-6), interleukin-10 (IL-10), or tumor necrosis factor (TNF) in critically ill patients (Table 3).