Red blood cell adhesion to ICAM-1 is mediated by fibrinogen and is associated with right-to-left shunts in sickle cell disease

Abstract

Sickle cell disease (SCD), which afflicts 100 000 Americans, as well as millions worldwide, is associated with anemia, lifelong morbidity, and early mortality. Abnormal adhesion of sickle red blood cells (RBCs) to activated vascular endothelium may contribute acutely to the initiation of painful vaso-occlusive crises and chronically to endothelial damage in SCD. Sickle RBCs adhere to activated endothelium through several adhesion mechanisms. In this study, using whole blood from 17 people with heterozygous SCD (HbS variant) and 55 people with homozygous SCD (HbSS) analyzed in an in vitro microfluidic assay, we present evidence for the adhesion of sickle RBCs to immobilized recombinant intercellular adhesion molecule 1 (ICAM-1). We show that sickle RBC adhesion to ICAM-1 in vitro is associated with evidence of hemolysis in vivo, marked by elevated lactate dehydrogenase levels, reticulocytosis, and lower fetal hemoglobin levels. Further, RBC adhesion to ICAM-1 correlates with a history of intracardiac or intrapulmonary right-to-left shunts. Studies of potential ICAM-1 ligands on RBC membranes revealed that RBC–ICAM-1 interactions were mediated by fibrinogen bound to the RBC membrane. We describe, for the first time, RBC rolling behavior on ICAM-1 under high shear rates. Our results suggest that firm adhesion of sickle RBCs to ICAM-1 most likely occurs in postcapillary venules at low physiological shear rates, which is facilitated by initial rolling in high shear regions (eg, capillaries). Inhibition of RBC and ICAM-1 interactions may constitute a novel therapeutic target in SCD.

Assessment of Fibrinogen Macromolecules Interaction with Red Blood Cells Membrane by Means of Laser Aggregometry, Flow Cytometry, and Optical Tweezers Combined with Microfluidics

“…Intercellular adhesion molecules (ICAM) represent a family of integrin molecular complexes of different types, which play a significant role in the mechanisms of the interactions between different types of blood cells. In [81], the authors indicate that the sickle-cell RBC of patients after shunting do not directly interact with ICAM-1 on endothelium cells; rather, fibrinogen, bound by the RBC membrane, triggers the adhesive connection by forming an intercellular bridge without any additional molecular intermediate. ICAM-4 is expressed on the membrane of erythroid cells, giving them an ability to interact with several types of integrins expressed on other types of blood cells, i.e., white blood cells [82].…”

Red Blood Cells: Tethering, Vesiculation, and Disease in Micro-Vascular Flow

“…On the other hand, single cell microfluidic studies of the type performed by Alapan et al [175] and Kucukal et al [122] on sickle cell disease cells offer the potential for more detailed characterization of the interplay between adhesion and deformability. As mentioned just above, these types of studies are amenable to thorough analysis and can be developed to provide a novel diagnostic tool to study related properties such as whole blood viscosity mediated by cell adhesion in disease as, for example, reported by Kucukal et al [188].…”

“…Kucukal et al [121,122] and Kaul [123] have reviewed the role played by red blood cell adhesion in sickle cell disease while Jambou et al [124] have described a trogocytosislike mechanism for the interaction of malaria infected red blood cells with human brain endothelial cells. Moreover, Wautier and Wautier [108] and Zwaal et al [125] have reviewed research dealing focused on, and the molecular basis for, increased erythrocyte adherence to vascular endothelial cells; this included research that demonstrated enhanced adherence due to PS exposure that provided a molecular basis for enhanced RBC adherence in pathologies such as diabetes mellitus and central retinal vein occlusion [28].…”

Standardized microfluidic assessment of red blood cell–mediated microcapillary occlusion: Association with clinical phenotype and hydroxyurea responsiveness in sickle cell disease

“…This may be ascribed to variations in clinical management of SCD, such as transfusions or administration of HU, which have distinct impacts on the pathophysiology of SCD. [23][24][25][26] Many biorheological and hematological facets of SCD have been extensively studied to associate with disease severity, including RBC adherence, [27][28][29][30][31][32][33] hemodynamic changes, [34][35][36][37][38] HbS fractions, [39][40][41] HbF levels, 42,43 serum LDH levels, [44][45][46] and WBC counts. 47,48 However, the clinical impact of RBC deformability in the context of microcirculation, which denotes the ability of the cell to transverse microcapillary openings without obstructing the flow, is still poorly understood.…”