HECs were grown until confluency and were used within five passages. The majority of cells isolated by this method expressed markers of sinusoidal endothelium, such as liver/lymph node–specific intercellular adhesion molecule 3–grabbing non-integrin and lymphatic vessel endothelial receptor 1.21 In order to determine whether HECs have characteristics consistent with vessels seen in the inflamed liver, we studied the
expression of endothelial adhesion molecules with a cell-based enzyme-linked immunosorbent assay in HECs from normal (n = 3) and diseased livers (n = 3) according to the standard methodology.14 The protocol and antibodies are listed in the Supporting Information Materials and Methods and Supporting Information Table 1. The expression of cytokeratin 19 (biliary epithelial cells), cytokeratin click here 18 (hepatocytes), CD68 (macrophages), and CD11c (dendritic cells) markers was used along with CD31 (endothelial cell marker) to confirm the purity of HEC cultures by flow cytometry. The antibodies are presented in the Supporting Information Materials and Methods and Supporting Information Table 2.
Peripheral venous blood from PSC patients with IBD was collected into ethylene diamine tetraacetic acid tubes, and lymphocytes p38 MAPK inhibitors clinical trials were isolated by density gradient centrifugation over Lymphoprep Farnesyltransferase (Sigma) according to the established methodology.22 JY cells (a B-lymphoblastoid cell line expressing α4β7) were grown in Roswell Park Memorial Institute 1640 medium (Invitrogen) containing l-glutamine and 10% fetal bovine serum (FBS; Invitrogen).
Adenoviral constructs encoding wild-type (WT) human vascular adhesion protein 1 (hVAP-1) and enzymatically inactive hVAP-1 [Tyr(Y)471Phe(F)] have been previously described.23 Before their use, the enzymatic activity of VAP-1 transfectants was confirmed with the Amplex UltraRed method, which is described in the Supporting Information Materials and Methods. HECs were cultured until confluency, washed in phosphate-buffered saline to ensure the complete removal of human serum, and infected with the constructs at an optimal multiplicity of infection of 600 for 4 hours in endothelial basal medium 2 (Clonetics, Lonza) supplemented with 10% FBS. Transfected cells were then incubated with TNF-α (20 ng/mL; Peprotech) alone or in combination with MA (50 μM; Sigma-Aldrich) for 2 hours. Formaldehyde (HCHO), ammonia (NH3), and hydrogen peroxide (H2O2) are produced during the VAP-1–catalyzed deamination of MA. In order to determine whether these end products had a role in the induction of MAdCAM-1, untransfected HECs were exposed to 1 or 10 μM H2O2 (BDH Prolabo), NH3 (Merck; 8 M), or HCHO (J.T. Baker; 13.44 M) for 4 hours.