An optimized confocal intravital microscopy protocol for long-term live imaging of murine F-actin organization during naïve lymphocyte migration.

Actin plays a crucial role during cell motility, but the organization of F-actin filaments during lymphocyte migration has not been visualized . Here, we present a 4D imaging platform using high-resolution confocal intravital microscopy to precisely determine the F-actin filament profile during lymphocyte transendothelial migration and interstitial migration. This protocol allows prolonged live imaging by laser scanning microscopy with advanced spatial resolution compared with the traditional multi-photon intravital microscopy techniques.

In Vivo F-Actin Filament Organization during Lymphocyte Transendothelial and Interstitial Migration Revealed by Intravital Microscopy.

Actin is essential for many cellular processes including cell motility. Yet the organization of F-actin filaments during lymphocyte transendothelial migration (TEM) and interstitial migration have not been visualized. Here we report a high-resolution confocal intravital imaging technique with LifeAct-GFP bone marrow reconstituted mice, which allowed visualization of lymphocyte F-actin in vivo.

Platelet activation and platelet-leukocyte aggregation elicited in experimental colitis are mediated by interleukin-6.

There is growing evidence for an interdependence of inflammation, coagulation, and thrombosis in acute and chronic inflammatory diseases. Inflammatory bowel diseases (IBD) are associated with a hypercoagulable state and an increased risk of thromboembolism. Although the IBD-associated prothrombogenic state has been linked to the inflammatory response, the mediators that link these 2 conditions remain unclear.

Platelet abnormalities during colonic inflammation.

Patients with inflammatory bowel disease are susceptible to microvascular thrombosis and thromboembolism. The increased incidence of thrombosis is accompanied by enhanced coagulation and abnormalities in platelet function. Clinical studies have revealed thrombocytosis, alterations in platelet activation, enhanced platelet-leukocyte interactions, and elevated plasma levels of prothrombotic cytokines.