Detection of extracellular histone H4 and CXCL10 in patient material.

(A) Immunostaining of snap-frozen tissue biopsies from a patient with S. pyogenes deep tissue infection (upper level) and a healthy donor (lower level) are depicted. Histone H4 staining is shown in red, CXCL10 in green, and DNA (DAPI) in blue. The boxed areas provide a larger magnification (right side). Co-localization of histone H4 and CXCL10 is shown in yellow and indicated by arrows. The image shows staining of one representative patient biopsy out of three analyzed. (B) CXCL10 was measured in the blood plasma from patients admitted at the ICU suffering from septic shock or non-septic critical illness (n = 15), patients with milder infections (upper respiratory tract viral infections or gastroenteritis) (n = 15) and healthy individuals (n = 10).