CD226 monoclonal antibody induces variation of intracytosolic free calcium level in human umbilical vein endothelial cells / 生理学报

ABSTRACT

In order to study the possible mechanism of CD226 monoclonal antibody (mAb)-mediated intracellular message transduction in human umbilical vein endothelial cells (HUVECs), the influence of CD226 mAb and its cross-linking by secondary antibody (II Ab) on the concentration changes in [Ca(2+)](i) in the HUVECs under different conditions were determined by confocal laser scanning microscopy. The main results are as follows. (1) When the culture medium was balanced by Hanks Buffer, [Ca(2+)](i) in HUVECs increased slowly after stimulation by CD226 mAb, whereas [Ca(2+)](i) increase was accompanied by [Ca(2+)](o) decrease after the mAb was cross-linked by goat anti-mouse IgG. Then [Ca(2+)](i) and [Ca(2+)](o) all returned to the normal level. (2) When the culture medium was balanced by D-Hanks buffer, [Ca(2+)](i) in HUVECs showed little variation when the cells were stimulated by CD226 mAb, but [Ca(2+)](i) decreased markedly after cross-linking. (3) When HUVECs were pretreated with EGTA, there was no variation in [Ca(2+)](i) of HUVECs after CD226 mAb stimulation alone or cross-linking of the mAb. Our results suggest that stimulation by CD226 mAb and cross-linking by goat anti-mouse IgG induce the variation of [Ca(2+)](i) in HUVECs under different conditions and the variation of [Ca(2+)](i) in HUVECs may play an important role in many physiological and pathological processes.