This proposal focuses on the adhesogenic responses of endothelial cells to agonists germane to sickle cell disease.
The specific aims are to test the following hypotheses: 1) that thrombin and hypoxia (I/R) enhance EC adhesivity for SS RB; 2) that specific EC adhesive molecules account for increased adhesivity; and 3) that identifiable cellular mechanisms account for the increased adhesivity.
Aims 1 and 2 will be studied in vitro and, using a mouse model of sickle cell disease, in vivo. The singular focus on activated endothelial cell adhesivity provides an innovative perspective to this proposal. The availability of a transgenic knockout sickle cell mouse model highly concordant with the human disease and of a state-of-the-art intravital microscopy system provide an exceptional opportunity to verify in vivo the importance of in vitro adherence phenomena. These experiments are anticipated to enhance our understanding of the molecular mechanisms of sickle erythrocyte-endothelial adherence, improve our grasp of the pathophysiology of sickle cell vasoocclusion, and expand our knowledge of endothelial cell biology. They may provide the basis for future therapeutic interventions.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL064396-04
Application #
6617851
Study Section
Hematology Subcommittee 2 (HEM)
Program Officer
Evans, Gregory
Project Start
2000-09-27
Project End
2004-07-31
Budget Start
2003-08-01
Budget End
2004-07-31
Support Year
4
Fiscal Year
2003
Total Cost
$319,663
Indirect Cost
Name
University of California San Francisco
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
094878337
City
San Francisco
State
CA
Country
United States
Zip Code
94143
Embury, Stephen H; Matsui, Neil M; Ramanujam, Sahana et al. (2004) The contribution of endothelial cell P-selectin to the microvascular flow of mouse sickle erythrocytes in vivo. Blood 104:3378-85
Embury, Stephen H (2004) The not-so-simple process of sickle cell vasoocclusion. Microcirculation 11:101-13
Hsu, Lewis L; Miller, Scott T; Wright, Elizabeth et al. (2003) Alpha Thalassemia is associated with decreased risk of abnormal transcranial Doppler ultrasonography in children with sickle cell anemia. J Pediatr Hematol Oncol 25:622-8
Matsui, Neil M; Varki, Ajit; Embury, Stephen H (2002) Heparin inhibits the flow adhesion of sickle red blood cells to P-selectin. Blood 100:3790-6