Tetramethylpyrazine inhibits phytohemagglutinin‐induced upregulation of ICAM‐1 and LFA‐1 mediated leukocyte adhesion

Article type: Research Article

Authors: Zhao, Hong^; | Zhu, Cheng | Li, Xiufeng | Dong, Xi | Zhuang, Fengyuan | Wang, Xiong | Stoltz, Jean‐François

Affiliations: Research Institute, China–Japan Friendship Hospital, Beijing 100029, China | Georgia Institute of Technology, Atlanta, GA 30332‐0405, USA | Beijing Polytechnic University, Beijing 100022, China | Angiohematology‐Hemorheology, LEMTA‐UMR‐CNRS 7563, Faculté de Médecine, 54500, Vandoeuvre‐les‐Nancy, France

Note: [] Corresponding author. Present address: Laboratoire d'Hémorheologie, Faculté de Médecine, Brabois, BP184, F‐54505 Vandoeuvre‐les‐Nancy, France. Fax: +33 3 83 59 26 43; E‐mail: [email protected]‐nancy.fr.

Abstract: The aim of this work was to study the effects of tetramethylpyrazine (TMP) on the interaction between lymphocyte function‐associated antigen‐1 (LFA‐1) and intercellular adhesive molecule‐1 (ICAM‐1) by micropipette technique. A pair of cells, i.e., a human lymphocyte or a SKW‐3 cell (human T cell leukemia), LFA‐1 was expressed on which cellular surfaces, and a RBC coupled with ICAM‐1, were the carriers for LFA‐1 and ICAM‐1. The adhesion probabilities of this pair of cells were mediated by specific interactions between ICAM‐1 and LFA‐1. Phytohemagglutinin (PHA) stimulation resulted in the significant increase in the adhesion probability compared to the resting lymphocyte. TMP treatment can inhibit such increase and even make the adhesion probability lower than the resting state. While the LFA‐1 expression has not changed significantly with PHA stimulation or with TMP treatment, which indicated that TMP inhibiting effects was realized by a possible conformation change.

Keywords: Leukocyte adhesion, ICAM‐1/LFA‐1, micropipette, tetramethylpyrazine

Journal: Clinical Hemorheology and Microcirculation, vol. 23, no. 2,3,4, pp. 145-151, 2000