Foreign body reaction

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. 

Miller, W.A. (1976). Experimental foreign body reactions to toothpaste abrasives. J. Periodontol. 47, 101-103. 

Subject to foreign body reaction, Inflammation rarely a consideration... 

Mineral oil may be absorbed systemically and cause a foreign-body reaction in lymphoid tissue. Also, in debilitated or recumbent patients, mineral oil may be aspirated, causing lipoid pneumonia. 

Intraperitoneal injection of metallic mercury in rats has produced sarcomas. The sarcomas develop without exception at those sites in direct contact with the metal, suggesting a foreign body reaction rather than chemical carcinogenesis. Mercuric chloride was tested for carcinogenicity in 2-year gavage studies in mice and rats." Three of 49 high-... 

PTFE implanted subcutaneously in animals has induced local sarcomas, suggesting a foreign body reaction rather than chemical carcinogenesis the lARC has determined that there is insufficient evidence to assess the carcinogenic risk, especially with regard to occupational exposure in humans. ... 

Hoffman129 and Baier 13° have reviewed most of the hypotheses and mechanisms suggested for blood compatibility in general and for the role of protein adsorption in particular. The safest statement one can make is that protein adsorption is indeed important in the blood compatibility process, in the compatibility of soft contact lenses, in the stability and acceptance of intraocular lenses, in the soft tissue foreign body reaction 131), and in virtually all situations where solid surfaces come into contact with physiologic environments. 

It is often demanded that the surface of polymeric biomaterials should exhibit permanent tenacious adhesion to soft connective and dermal tissues. However, conventional non-porous, polymeric materials will be encapsulated by a fibrous membrane generated de novo by surrounding fibroblasts, when subcutaneously implanted into the living body in contact with soft connective tissues. This is a typical foreign body reaction of the living system to isolate foreign materials from the host inside the body. On the other hand, it should be noted that the small gap present between a percutaneously-implanted device and the surrounding tissue provides a possible route for bacterial infection because of the lack of microscopic adhesion at the interface. 

The Role of the Wound-Site Macrophages in the Foreign Body Reaction... 

Coleman DL, King RN, Andrade JD. The foreign body reaction a chronic inflammatory response. Journal of Biomedical Materials Research 1974, 8, 199-211. 

Tang L, Eaton JW. Natural responses to unnatural materials a molecular mechanism for foreign body reactions. Molecular Medicine 1999, 5, 351-358. 

Kyriakides TR, Leach KJ, Hoffman AS, Ratner BD, Bomstein P. Mice that lack the angiogenesis inhibitor, thrombospondin 2, mount an altered foreign body reaction characterized by increased vascularity. Proceedings of the National Academy of Sciences of the United States of America 1999, 96, 4449M454. 

Puolakkainen P, Bradshaw AD, Kyriakides TR, Reed M, Brekken R, Wight T, Bomstein P, Ratner B, Sage EH. Compromised production of extracellular matrix in mice lacking secreted protein, acidic and rich in cysteine (SPARC) leads to a reduced foreign body reaction to implanted biomaterials. American Journal of Pathology 2003,162, 627-635. 

THE EARLY FOREIGN BODY REACTION (MINUTES TO DAYS)... 

The Effect of the Foreign Body Reaction on Chronic Biosensor Function... 

Before any discussion of potential targets or coping strategies to improve sensor performance, the foreign body reaction as understood by the scientific community must be reviewed. In this chapter, the foreign body reaction will be categorized into two broad segments minutes to days and days to months. 

Neutrophils are also rapidly attracted to the site of a foreign body reaction, but likely persist in large numbers for only a few days. They generally reside within blood vessels, but in response to signals such as histamine, which increases vascular permeability, neutrophils enter the extravascular space through a process known as diapedesis. A recent study by Wozniak found that nitric oxide produced by neutrophils plays an important role in loosening of total joint implants.11... 

These results should be contrasted with the situation with sensors that were implanted over 30 days. The lag in these devices rose to 15-30 min. There was also a decline in sensitivity of the sensors to glucose, sensor accuracy, and the degree of closed-loop glycemic control.4 Based on the known effects and time course of collagen deposition that occurs as part of the foreign body reaction,12 13 it is very likely that this decline in sensor function was a direct result of this process. The effect of the foreign body reaction on the function of biosensors has been comprehensively reviewed by Wisniewski and colleagues.14 15... 

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