L12 - Host response Flashcards
What are the effects of a biomaterial on the body?
Changes to wound healing, infection, toxicity, tumourigenesis, particle embolisation, hypersensitivity reactions
What effects can the body have on biomaterials?
Enzymatic degradation, calcification, abrasion and corrosion
What is the foreign body response?
Injury causes pt from the blood to lay down a scaffold that macrophages can adhere to. Frustrated phagocytosis occurs if the macro can’t digest the material. This may cause macro to fuse - super cell
What is fibrous encapsulation?
Tissue response to implanted biomaterials
Abundant deposition of ECM
Isolation of biomat from local tissue environment - can cause problems for diffusion and vascularisation
What are some issue associated with TE constructs?
Infection - bacterial biofilm with AB resistance
Toxicity - products from construct may be harmful. Stent thrombosis
Tumours - not proven to be causal but there have been tumours found at the site of implants
What is immunoisolation?
Use of a semipermeable membrane that allows nutrients in and metabolites out. Doesn’t let immune cells in . Micro/macroencapsulation and ultrathin coatings - thinner = better diffusion of nutrients
