title: Stimulation of human red blood cells leads to Ca2+-mediated intercellular adhesion.
abstract: Red blood cells (RBCs) are a major component of blood clots, which form physiologically as a response to injury or pathologically in thrombosis. The active participation of RBCs in thrombus solidification has been previously proposed but not yet experimentally proven. Holographic optical tweezers and single-cell force spectroscopy were used to study potential cell-cell adhesion between RBCs. Irreversible intercellular adhesion of RBCs could be induced by stimulation with lysophosphatidic acid (LPA), a compound known to be released by activated platelets. We identified Ca(2+) as an essential player in the signaling cascade by directly inducing Ca(2+) influx using A23187. Elevation of the internal Ca(2+) concentration leads to an intercellular adhesion of RBCs similar to that induced by LPA stimulation. Using single-cell force spectroscopy, the adhesion of the RBCs was identified to be approximately 100 pN, a value large enough to be of significance inside a blood clot or in pathological situations like the vasco-occlusive crisis in sickle cell disease patients.
authors: Experimental Physics Department, Saarland University, 66123 Saarbruecken, Germany.
authors: Patrick
authors: P
authors: Steffen
authors: Achim
authors: A
authors: Jung
authors: Duc Bach
authors: DB
authors: Nguyen
authors: Torsten
authors: T
authors: Müller
authors: Ingolf
authors: I
authors: Bernhardt
authors: Lars
authors: L
authors: Kaestner
authors: Christian
authors: C
authors: Wagner