Synthetic Polymers for Biotechnology and Medicine - Original PDF
نویسندگان: Ruth Freitag
خلاصه: One of the most powerful group of chemicals in the body are organic compounds
collectively referred to as hormones. The glands responsible for the production and
release of hormones comprise the endocrine system. Endocrine activities have been
identified in certain organs, such as the heart, kidneys, duodenum, liver and the islets of Langerhans in
the pancreas (which contains the insulin gland), which are normally associated with other
system functions.
There have been numerous attempts to replace organ function using cell transplantation
including direct injections of dissociated cells into organs such as the liver, kidney or spleen.1-5
Subcutaneous and intraperitoneal routes have also been evaluated.6-10 More recent investigations have applied extracellular matrix polymers as structural supports for cell transplantation
and immunoprotection.11,12 Potential medical applications of such “artificial cells” or “tissue
engineered” organoids include an extracorporeal bioartificial liver for detoxification,2 artificial
red blood substitutes,13 the extracorporeal artificial kidney for hemodialysis,14 immunosorbents15
and drug delivery systems.16The transplantation of immunoisolated (microencapsulated) cells
represents another emerging area in biotechnology research and commercialization. Under
such a scenario, the encapsulated cells, which could be a xenograft, would be hidden from the
immune system of the body, but would still be able to respond to extracellular stimuli
(e.g., blood glucose), with the required hormone, in the case of diabetes therapy insulin,
secreted into the systemic circulation. Other applications of the microencapsulation concept
include the encapsulation of genetically modified cells, which represents a novel approach to
somatic gene therapy.17
This chapter will review recent advances in cell encapsulation from material science, technological and tissue-related perspectives. Cell coating, microencapsulation devices and
bioartificial organs will be discussed with the artificial pancreas and treatment of diabetes used
as a case study denominator throughout the review.