Sticking together: Polymerization of sickle hemoglobin drives the multiscale pathophysiology of sickle cell disease

Sickle cell disease is a hereditary disorder in which the pathophysiology is driven by the aggregation of a mutant (sickle) hemoglobin (HbS). The self-assembly of deoxygenated sickle hemoglobin molecules into ordered fiber structures has consequences extending to the cellular and rheological levels, stiffening red blood cells and inducing pathological flow behavior. This review explores the current understanding of the molecular processes involved in the polymerization of hemoglobin in sickle cell disease and how the molecular phase transition creates quantifiable changes at the cellular and rheological scale, as well as, identifying knowledge gaps in the field that would improve our understanding of the disease and further improve treatment and management of the disease.