Bio-inspired Nanomedicine Strategies for Artificial Blood Components

摘要

Blood is a fluid connective tissue where living cells are suspended in non-cellular liquid matrix. The cellular components of blood render gas exchange (RBCs), immune surveillance (WBCs) and hemostatic responses (platelets), and the non-cellular components (salts, proteins etc.) provide nutrition to various tissues in the body. Dysfunction and deficiencies in these blood components can lead to significant tissue morbidity and mortality. Consequently, transfusion of whole blood or its components is a clinical mainstay in the management of trauma, surgery, myelosuppression and congenital blood disorders. However, donor-derived blood products suffer from issues of shortage in supply, need for type matching, high risks of pathogenic contamination, limited portability and shelf-life, and a variety of side-effects. While robust research is being directed to resolve these issues, a parallel clinical interest has developed towards bioengineering of synthetic blood substitutes that can provide blood’s functions while circumventing the above problems. Nanotechnology has provided exciting approaches to achieve this, using materials engineering strategies to create synthetic and semi-synthetic RBC substitutes for enabling oxygen transport, platelet substitutes for enabling hemostasis and WBC substitutes for enabling cell-specific immune response. Some of these approaches have further extended the application of blood cell-inspired syntheticand semi-synthetic constructs for targeted drug delivery and nanomedicine. The currentarticle will provide a comprehensive review of the various nanotechnology approaches todesign synthetic blood cells, along with a critical discussion of successes and challengesof the current state-of-art in this field.