Initial observations suggested that C-C motif chemokines exclusively mediate chemotaxis of mononuclear cells. In addition, recent studies also implicated these chemotactic cytokines in the recruitment of neutrophils. The underlying mechanisms remained largely unknown. Using in vivo microscopy on the mouse cremaster muscle, intravascular adherence and subsequent paracellular transmigration of ne...

Canine transmigration is a very rare dental anomaly in which an unerupted mandibular canine migrates, crossing the mandibular midline. This unusual condition is most often diagnosed by chance during a routine X-ray examination. The most common clinical signs announcing the presence of this anomaly are over-retention of the deciduous canine and the absence of permanent canine from the dental arc...

Leukocyte transendothelial migration involves the active participation of the endothelium through the formation of apical membrane protrusions that embrace adherent leukocytes, termed docking structures. Using live-cell imaging, we find that prior to transmigration, endothelial docking structures form around 80% of all neutrophils. Previously we showed that endothelial RhoG and SGEF control leu...

OBJECTIVE Junctional adhesion molecule-C (JAM-C) is an adhesion molecule that has multiple roles in inflammation and vascular biology, but many aspects of its functions under pathological conditions are unknown. Here we investigated the role of JAM-C in leukocyte migration in response to ischemia reperfusion (I/R) injury. METHODS AND RESULTS Pretreatment of mice with soluble JAM-C (sJAM-C), u...

Transmigration of leukocytes across the endothelial barrier is a tightly controlled process involving multiple steps, including rolling adhesion, firm adhesion, and then penetration of leukocytes through the endothelial monolayer. While the key molecular signals have been described in great detail, we are only just beginning to unveil the mechanical forces involved in this process. Here, using ...

Patients with risks of ischemic injury, e.g. during circulatory arrest in cardiac surgery, or after resuscitation are subjected to therapeutic hypothermia. For aortic surgery, the body is traditionally cooled down to 18 °C and then rewarmed to body temperature. The role of hypothermia and the subsequent rewarming process on leukocyte-endothelial interactions and expression of junctional-adhesio...

The physiologic role of L-selectin shedding is unknown. Here, we investigate the effect of L-selectin shedding on firm adhesion and transmigration. In a tumor necrosis factor alpha-induced model of inflammation, inhibition of L-selectin shedding significantly increased firm adhesion and transmigration by a lymphocyte function-associated antigen (LFA)-1 and intercellular adhesion molecule (ICAM)...

An in vitro model consisting of endothelium grown on collagen was used to investigate how mononuclear phagocytes traverse endothelium in the basal-to-apical direction (reverse transmigration), a process that mimics their migration across vascular and/or lymphatic endothelium during atherosclerosis and resolution of inflammation, respectively. Monoclonal antibody (MoAb) VIC7 against tissue facto...

The transmigration of African trypanosomes across the human blood-brain barrier (BBB) is the critical step during the course of human African trypanosomiasis. The parasites Trypanosoma brucei gambiense and T. b. rhodesiense are transmitted to humans during the bite of tsetse flies. Trypanosomes multiply within the bloodstream and finally invade the central nervous system (CNS), which leads to t...

Neutrophil(PMN) transepithelial migration during inflammatory episodes involves a complex series of adhesive interactions and signaling events. Previous studies have shown that key adhesive interactions between leukocyte CD11b/CD18 and basally expressed proteoglycans followed by binding to desmosomal-associated JAM-C are key elements of the transmigration response. Here we provide the first evi...