Genetic disorders of haemoglobin (haemoglobinopathies), including the thalassaemias and sickle cell anaemia, abound in historically malarious regions, due to the protection they provide against death from severe malaria. Despite the overall spatial correlation between malaria and these disorders, inter-population differences exist in the precise combinations of haemoglobinopathies observed. Gre...

Sickle red blood cell (RBC) adhesion to the endothelium and to exposed, underlying subendothelial proteins is believed to contribute to vascular occlusion in sickle cell disease. Laminin, a major component of the subendothelium, supports significant adhesion of sickle, but not normal RBCs. The purpose of this study was to define the adhesive region for sickle RBCs within a human laminin prepara...

The pathophysiology of vaso-occlusive crisis in sickle cell disease involves interactions among blood cells, plasma proteins, and vessel wall components. The initial goal of this work was to quantify the adhesion of sickle red blood cells (RBCs) to fibronectin immobilized on glass under both static and dynamic shear stress conditions. High-power microscopic inspection of static assay plates sho...

BACKGROUND Sickle cell disease (SCD) is a hereditary blood disorder prevalent in tribal regions of India. SCD can increase complications during pregnancy and in turn negatively influence pregnancy outcomes. This study reports the analysis of tribal maternal admissions in the community-based hospital of SEWA Rural (Kasturba Maternity Hospital) in Jhagadia block, Gujarat. The objective of the stu...

Previous studies had indicated that recombinant and natural human sickle hemoglobin had similar chemical properties (Martin de Llano, J. J., Schneewind, O., Stetler, G., and Manning, J. M. (1993) Proc. Natl. Acad. Sci. U.S.A. 90, 918-922). In the present study, additional biochemical and physiological characterization of some primary through quaternary structural features of recombinant sickle ...

Sickle red blood cells (RBC) are subject to a number of important cellular changes and selection pressures. In this study, we validated a biotin RBC label by comparison to the standard 51Cr label, and used it to study changes that occur in sickle cells as they age. Sickle RBC had a much shorter lifespan than normal RBC, but the two labels gave equivalent results for each cell type. A variable n...

OBJECTIVE Sickle cell disease (SCD) is characterized by extensive hemolysis, increased cellular adhesion, and vaso-occlusion. Tissues from sickle patients express heme oxygenase-1 (HO-1), the enzyme that degrades free heme/hemoglobin to the signaling molecule carbon monoxide, and the antioxidants biliverdin/bilirubin. Here, we examined the HO response in endothelial cells exposed to human sickl...

BACKGROUND AND OBJECTIVES Children with sickle cell disease are considered at high risk for complications from influenza infection and are recommended to receive annual influenza vaccination. However, data on the safety of influenza vaccination in children with sickle cell anemia are sparse. METHODS Using a retrospective cohort of children aged 6 months to 17 years in 8 managed care organizat...

Activation of vascular endothelium plays an essential role in vasoocclusion in sickle cell disease. The anti-inflammatory agents dexamethasone and adhesion molecule-blocking antibodies were used to inhibit endothelial cell activation and hypoxia-induced vasoocclusion. Transgenic sickle mice, expressing human alpha-, beta(S)-, and beta(S-Antilles)-globins, had an activated vascular endothelium i...

The tendency for sickle cells to adhere to each other is increased in oxygenated sickle blood in parallel with cell density. The increased adherence of these cells occurred despite their reduced deformability and diminished ability to form rouleaux. Using a method developed in our laboratory, we measured the yield stress: a sensitive index of cell-cell adhesion of deoxygenated suspensions of si...