Dynamic
Investigation of Leukocyte-Endothelial Cell Adhesion Interaction under Fluid
Shear Stress in Vitro

LING Xu, YE Jian-Feng, ZHENG
Xiao-Xiang*

( Department
of Biomedical Engineering, Zhejiang University, Hangzhou 310027, China )

Abstract        To
establish a method to investigate the dynamic adhesion between leukocytes and
human umbilical vein endothelial cells (HUVECs) under definite shear stress. A
parallel plate flow chamber system was developed to produce the definite shear
stress in vitro. After the cultured HUVECs were loaded in the flow chamber, the
circulation solution containing acridine orange (AO)-labeled leukocytes was
perfused to flow through chamber at 0.71 dynes/cm². In this case,
leukocyte-endothelial cell adhesion process was induced. Lipopolysaccharide (LPS)
was used as the chemical stimulus and dexamethasone (DXM) was used as the
anti-inflammatory reagent. The adhesion process was recorded in videotape by
Olympus IX70 fluorescence microscope and CCD-camera. Then the number of
adhesion leukocyte, slow and fast rolling velocities of leukocytes on the
surface of HUVECs were measured based on the captured images. The number of
static adhering and slow rolling leukocytes on the HUVECs treated with LPS was
significantly increased by 23.7-fold and 4.1-fold compared with that of the
control group. Meanwhile, both the slow and fast rolling velocities of the
leukocytes on HUVECs treated with LPS were significantly decreased by 25.6% and
26.1%. When HUVECs were treated with both LPS and DXM, the effect of LPS was
inhibited obviously. This developed method can be used in studying ECs adhesion
function affected by different chemical and physical stimulus and evaluating
the various compounds interfering with cell adhesion.

Key words     endothelial
cells; shear stress; parallel plate flow chamber; leukocytes; adhesion

*Corresponding
author: Tel, 86-571-87951091; Fax, 86-571-87951676;
e-mail, [email protected]