In vivo characterization of the inflammatory properties of poly(tetrafluoroethylene) particulates

Abstract

Suburothelial injections of particulate poly(tetrafluoroethylene) (PTFE) is becoming a widely accepted treatment for a number of urological disorders. Because little is known about the long-term histologic morphology of the injection site, this animal study was performed. Three populations, each consisting of two mongrel dogs, five New Zealand White rabbits, and 10 BALB/c mice, were injected with poly(tetrafluoroethylene) particulate in a glycerine carrier (Polytef Paste) and were followed for a period of 1 week, 3 months, 6 months, and 1 year. Mice received one subcutaneous dorsal injection each, rabbits received two subareolar injections each, and dogs received three subareolar injections each in addition to two periurethral injections. Histologic examination of the biopsy sites revealed a persistent chronic inflammatory reaction with progressive growth of the involved tissue volume. In addition to giant cells and macrophages, lymphocytes became apparent at 3 months and constituted up to 40% of the cellular infiltrate by 1 year. Plasma cells were also noted at the 1-year period in the rabbit model. The progressive growth of the inflammatory pseudo-tumors evoked by injected PTFE may compromise the long-term safety of certain urological procedures involving particulate PTFE.

Rho GTPase protein expression and activation in murine monocytes/macrophages are not modulated by model biomaterial surfaces in serum-containing in vitro cultures

“…Chemistries selected included: TCPS, the current 'gold standard' for adherent cell culture, PS, commonly employed for suspension culture, PLA an FDA-approved synthetic bioerodible polymer and Teflon ® Amorphous Form (AF), (4,5-difluoro-2, 2-bis (trifluoromethyl)-1,3-dioxole co-polymerized with tetrafluoroethylene) the soluble analog of Teflon ® , a highly hydrophobic fluoropolymer with a long history of use in biomaterials implants [29,30]. Our previous work characterized these surface chemistries using X-ray photoelectron spectroscopy and correlated surface characteristics to endothelial cell culture support.…”

Cellular profile and cytokine production at prosthetic interfaces

“…Thus, the prosthetic interface provides a complex series of interactions of cells, cytokines and other substances which modulate bone remodelling. With cemented implants, differences were also found in the T-lymphocyte subgroups, suggesting a possible role for immunological processes in osteolysis, but this is con- troversial and there are studies which advocate 21,32,[43][44][45][46][47][48] and refute [49][50][51][52][53][54] a role for T-cell modulation of the macrophage response to biomaterials. 55,56 With cementless prostheses there were fewer differences in cell number and cytokine profile in the various groups.…”

Evaluation of the responses of human peritoneal macrophages to a range of biomaterials using reflectance light microscopy

“…The membrane surrounding stable total hip replacements are characterized by the presence of a large population of fibroblasts with relatively few macrophages whereas in the membrane around loose total hip replacements a greater proportion of macrophages were observed [6]. Animal studies have highlighted the presence of inflammatory cells, including macrophages, surrounding implants of PMMA bone cement [7], titanium [8], polyglactin and dacron [9].…”