A novel mouse-driven ex vivo flow chamber for the study of leukocyte and platelet function

• Published in: American Journal of Physiology: Cell Physiology Vol. 286; no. 4; pp. C876 - C892
• Main Authors: Hafezi-Moghadam, Ali, Thomas, Kennard L, Cornelssen, Christian
• Format: Journal Article
• Language: English
• Published: United States 01.04.2004
• Subjects: Animals; Blood Platelets - physiology; Extracorporeal Circulation - methods; Leukocyte Rolling - physiology; Leukocytes - physiology; Mice; Mice, Inbred C57BL; Models, Biological; Pressure; Pulsatile Flow - physiology; Stress, Mechanical; Thrombosis - physiopathology
• ISSN: 0363-6143; 1522-1563
• DOI: 10.1152/ajpcell.00500.2003

1 Harvard Medical School and 2 Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts 02114; and 3 Institute of Mechanics, Faculty V, Technical University, 10623 Berlin, Germany Submitted 12 November 2003 ; accepted in final form 26 November 2003 Various in vitro and in vivo techniques exist for study of the microcirculation. Whereas in vivo systems impress with their physiological fidelity, in vitro systems excel in the amount of reduction that can be achieved. Here we introduce the autoperfused ex vivo flow chamber designed to study murine leukocytes and platelets under well-defined hemodynamic conditions. In our model, the murine heart continuously drives the blood flow through the chamber, providing a wide range of physiological shear rates. We used a balance of force approach to quantify the prevailing forces at the chamber walls. Numerical simulations show the flow characteristics in the chamber based on a shear-thinning fluid model. We demonstrate specific rolling of wild-type leukocytes on immobilized P-selectin, abolished by a blocking MAb. When uncoated, the surfaces having a constant shear rate supported individual platelet rolling, whereas on areas showing a rapid drop in shear platelets interacted in previously unreported grapelike conglomerates, suggesting an influence of shear rate on the type of platelet interaction. In summary, the ex vivo chamber amounts to an external vessel connecting the arterial and venous systems of a live mouse. This method combines the strengths of existing in vivo and in vitro systems in the study of leukocyte and platelet function. autoperfused flow chamber; intravital microscopy; inflammation; thrombus formation Address for reprint requests and other correspondence: A. Hafezi-Moghadam, Massachusetts Eye and Ear Infirmary, Harvard Medical School, 325 Cambridge St., Boston, MA 02114 (E-mail: Ali_Hafezi-Moghadam{at}meei.harvard.edu ).