VARIATION IN CYTOKINES INDUCED BY PARTICLES FROM DIFFERENT PROSTHETICMATERIALS

Particles of prosthetic material stimulate macrophages to release cyto kines, which may cause bone loss and loosening of the prosthesis. This study investigates the possibility that particles of different prosth etic materials may induce different cytokines and thus have different effects on bone remodeling. The in vitro response of human monocytes t o particles of cast and forged cobalt chrome alloy, stainless steel, a nd titanium aluminum vanadium alloy were compared. There was no differ ence in the biologic response to cobalt-chrome particles derived from cast or forged material. Cobalt-chrome particles were toxic to the cel ls, but titanium aluminum vanadium particles did not affect cell viabi lity. Stainless steel particles were approximately 10 times more toxic than were cobalt-chrome particles, All particles induced the release of tumor necrosis factor and interleukin Ip; stainless steel particles were the most potent stimulators of interleukin 1 beta; titanium alum inum vanadium particles were the strongest stimulators of interleukin 6 and prostaglandin 2.The study showed that particles derived from pro sthetic materials of different metal compositions can elicit significa ntly different biologic responses. Understanding these different respo nses may help identify materials better suited for prostheses.