Foreign body response reaction

The first synthetic polyglycoHc acid suture was introduced in 1970 with great success (21). This is because synthetic polymers are preferable to natural polymers since greater control over uniformity and mechanical properties are obtainable. The foreign body response to synthetic polymer absorption generally is quite predictable whereas catgut absorption is variable and usually produces a more intense inflammatory reaction (22). This greater tissue compatibihty is cmcial when the implant must serve as an inert, mechanical device prior to bioresorption. 

De Scheerder I, Wang K, Wilczek K, et al, Local methylpred-nisolone inhibition of foreign body response to coated intracoronary stents, Coronary Artery Dis 1996 7 161-166. Baker J, Nikolaychik V Zulich A, et al, Fibrin coated stents as depot to deliver RGD peptide inhibit vascular reaction in atherosclerosis rabbit model [abstr], J Am Coll Cardiol I 996 27 197A,... 

CPCs are nontoxic to cells, biocompatible, and osteoconductive. Furthermore, CPCs are biologically active such that they remodel and incorporate in host bone, and thus do not induce a foreign-body response.These biomaterials set at a physiological pH with minimal reaction exotherm, and do not release toxic monomers or solvents.There are two primary classes of CPCs (a)... 

Host-derived collagen tissues are also referred to as autogenous grafts and eliminate complications associated with immune reactions, foreign body response, and eventual rejection. They retain the native biomechanical properties of the ECM... 

In contrast to the foreign body response, the hypersensitivity reaction consisted of the organisation of epithehoid ceUs into tubercles. Multinucleate giant cells occurred both in developing granulomas (4 weeks) and adjacent to necrotic areas (Black and Epstein 1974). 

Adsorption of proteins from solution onto synthetic materials is a key factor in the response of a living body to artificial implanted materials and devices. Adsorbed proteins mediate cell attachment and spreading through specific peptide sequence-integrin receptor interactions and may therefore favorably influence the mechanical stability of the subsequently developed tissue—implant interface. However, the uncontrolled nonspecific adsorption of proteins from the extracellular matrix results in interfaces with many types of proteins in different conformations—a situation that is believed to cause deleterious reactions of the body, such as foreign-body response and fibrous encapsulation. ... 

The acute CNS response starts within hours of injury and is characterized by migration of astrocytes and microglia to the injury site [102, 103]. The acute inflammatory reaction peaks within a week after injury [104] and is then gradually replaced by the long-term foreign body response. 

Fig. 15 Central nervous system reaction at the implant/tissue interface four weeks after implantation of a silicon microelectrode. The microelectrode was placed at the left drawn to scale) and the foreign body response is indicated by activated microglia (ED-1 stain), astrocytes (GFAP), local neuron loss (NeuN), and reduced neurofilament (NF) density [109]...

In addition, silicone polymers in both gel and elastomer forms have been shown to induce a typical subcutaneous foreign body reaction and fibro sarcoma development in rats. The lower-molecular weight silicone polymers may migrate into the adjacent tissues or stimulate other cellular and immunological response. 

Testes from the males examined 43 days after the 8-D treatment appeared normal. However, the epididymis was involved in an inflammatory process with sperm granulomas formation. The granulomatous epididymal lesion resembled the lesion seen in auto-immune reaction following bacterial infections or tissue response to foreign bodies (16, 17,... 

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