PubMed · 7877507
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
J P Robinson, P K Narayanan, W O Carter. 1994. Functional measurements using HL-60 cells.. https://doi.org/10.1016/s0091-679x(08)61088-2
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Human cytomegalovirus (CMV) has been shown to alter adhesion molecule expression on permissive cells such as endothelial cells. The aim of the present study was to investigate expression of receptors for these molecules on CMV infected polymorphonuclear leukocytes (PMNLs). CMV-induced variations on cellular integrin expression were examined using an in vitro system to obtain infected PMNLs. A triparametric flow cytometry approach was developed, which allows combined detection, in a single experiment, of both viral intranuclear antigen in the selected PMNLs and cellular CD11/CD18 expression. Comparison of infected PMNLs with uninfected cells showed a decrease of up to 50% in the expression of CD11b, CD11c, and CD18. This study thus demonstrates that the presence of CMV in PMNLs, which characterizes active infection, modifies the expression of integrins and may thus affect cell-to-cell interactions and immune functions.
OBJECTIVE: Systemic inflammatory response syndrome and infectious complications are major causes of morbidity and mortality after cardiopulmonary bypass. Recent work in adult patients suggests that the balance between proinflammatory and anti-inflammatory mediators is important. We hypothesized that the expression of different function-related receptors on circulating monocytes might reflect the net response of the inflammatory reaction. METHODS: We performed a prospective and observational study in a tertiary pediatric cardiac center in a population of children (n = 40) undergoing elective cardiac surgery. Expression of receptors on the surface of monocytes was assessed before, during, and after surgical intervention. RESULTS: Early monocyte activation was demonstrated by changes of the expression of the chemokine receptor CCR2, which was inversely correlated with plasma levels of monocyte chemotactic protein 1 (rho = -0.54, P = .002). High levels of monocyte chemotactic protein 1 were found in children with high expression of the adhesion receptor CD11b/CD18 on circulating monocytes. The intensity of human leukocyte antigen DR expression rapidly decreased in all children after the onset of cardiopulmonary bypass ( P < .001). Low human leukocyte antigen DR expression was correlated with increased plasma levels of interleukin 10 postoperatively. Children who had signs of bacterial pneumonia postoperatively had lower levels of human leukocyte antigen DR expression before surgical intervention (relative risk, 13.3; P = .007). CONCLUSIONS: The expression of monocyte function-related receptors is altered after cardiac surgery. Early activation of monocytes by monocyte chemotactic protein 1 possibly released from the heart is followed by an anti-inflammatory response with suppression of monocyte human leukocyte antigen DR expression. The increased risk of bacterial infection after pediatric cardiac surgery can be anticipated by surveillance of monocyte function before surgical intervention.
Migration of dendritic cells (DC) from sentinel sites to lymphoid tissue entails the initiation and coordination of a complex series of cytoskeletal rearrangements resulting in polarised protrusion, formation of new adhesion points, and detachment. Although many diverse receptor-ligand interactions stimulating DC maturation and migration have been identified, the changes that occur in the structure of the actin cytoskeleton during these processes have received little attention. When derived in vitro, immature DC floated in clumps, and upon addition of maturation stimuli such as lipopolysaccharide (LPS), they rapidly adhered, developed polarity, and assembled actin-rich structures known as podosomes at the leading edge of the cell. Podosome assembly was associated with the specific recruitment of beta2 integrins, which in the absence of the Wiskott Aldrich Syndrome protein (WASp), did not occur. As maturation progressed, normal DC once again became rounded and devoid of podosomes. This change in morphology was closely associated with a quantitatively reduced ability to adhere to fibronectin or ICAM-1-coated surfaces. In immature DC, failure to form podosomes or selective inhibition of the CD18 component of podosomes resulted in a similarly reduced ability to adhere to ICAM-1, indicating that podosomes, through CD18, are necessary for tight adhesion to this ligand. We, therefore, propose that podosomes provide an essential link between directional cell protrusion and achievement of DC translocation by establishing new dynamic anchor points at the front of the cell. The temporal regulation of podosome assembly during DC maturation also suggests that they may be most critical for early movement, perhaps during transmigration of lymphatic endothelium.