'Sickle-shaped' anemia was first clinically described in the US in 1910, and the mutated heritable sickle hemoglobin molecule was identified in 1949. The pathophysiology of SCD is a consequence of abnormal polymerization of sickle hemoglobin (HbS) and its effects on red cell membrane properties, shape, and density, and subsequent critical changes in inflammatory cell and endothelial cell function. Our goal is to understand the impact of CMA abnormalities in SCD, by interrogating a number of recognized interactions in a range of clinical phenotypes. To date, correlative studies in SCD, by us and others, have range between clinical reports, based on tests, interventions, and chart review of individuals or groups of individuals and, at the other extreme, identification of functional gene polymorphisms based on population studies. The investigators wish to augment these studies through a systematic examination of cellular membrane properties and activation status. Of hematologic disorders, SCD may be unusually susceptible to such an examination.

Novel biofluidic chip technology can investigate surface characteristics that are typically measured with conventional techniques, such as fluorescent activated cell sorting (FACS), immunohistochemistry, or microscopic imaging methods. In FACS, cells of interest are isolated, extensively processed, incubated with a fluorescent-labeled antibody and sorted by optical recognition. In the proposed SCD biofluidic chip (SCD biochip), the interrogating antibody coats the microchannel surface and captures the cell population(s) of interest, without processing, incubation, or in vitro manipulation. The SCD biochip can also quantitate cellular adherence to experimental biological surfaces that are comprised of subcellular components. The SCD biochip is technically simple and experimentally flexible, whereby the population of interest is retained on the chip and quantitated in situ. The microchip system allows retrieval of viable isolated cells for potential downstream processing, analysis, and in vitro culture.