AQP1 and Sepsis: Following confirmation that Aqp1 is expressed in human leukocytes, we prospectively followed temporal trends in Aqp1 mRNA levels using quantitative real-time PCR in ICU patients who were initially nonseptic but later developed nosocomial sepsis and subsequently septic shock (Figure 2A); mRNA levels of ICU patients who did not develop sepsis, upon ICU admission and discharge, are shown in Figure 2B. All 16 patients who developed sepsis and then septic shock had positive biological fluid cultures, with 11 out of 16 having positive blood cultures.