Figure 1.

MKs are increased in peripheral organs during sepsis. Autopsy pathology samples from patients that died from sepsis were evaluated for MKs. (A) MKs in the lungs were defined as large cells with dark, homogenous CD61+ staining (brown). An example of a lung image from a patient that died from heart disease as a negative control is shown in panel ia (hematoxylin and eosin, H&E) and ib (CD61). No MKs were observed in these images. A representative image of two lung images from a patient that died from sepsis are shown in panel iia/iiia (H&E) and iib/iiib (CD61), showing multiple MKs (green asterisks). Platelet staining is also noted (red asterisks). In some cases, a large dark staining basophilic nucleus can be seen in the H&E in the area of the CD61 staining. This was not always the case, which may be due to sectioning and imaging of slightly different planes. This also suggests that CD61 may be more accurate when counting MKs than H&E. A sample of bone marrow from a sepsis patient is shown in panel iva (H&E) and ivb (CD61) as an example of an MK with CD61 staining as a positive control (red box). (B) Glomeruli were evaluated for the presence of increased CD61 staining. Individual MKs could not be reliable counted within the glomeruli, therefore percent of CD61 stain/glomeruli was evaluated. A glomerulus from a control patient is shown in panel ia (CD61) and ib (H&E), with minimal CD61 staining. This is in contrast to a glomerulus from a patient with sepsis and disseminated intravascular coagulation (DIC), which has much higher amounts of CD61 staining along with microvascular thrombi within the glomerular capillaries (green asterisk). Upon evaluation, there was significantly higher pulmonary MKs (C) and glomerular CD61 staining (D) in the sepsis patients as compared to control. Significance is calculated via student t-test with significance being defined as p < 0.05 (*). Scale bars are: Ai-ii, 100 μm, Aiii-iv and C, 50 μm.