Interleukin-1 production by activated macrophages surrounding loosened orthopaedic implants: a potential role in XXXX .

@entity3647 @entity404 @entity1356 @entity3061 @entity405
@entity1356 producing cells at the bone-implant interface obtained during revision of loosened total joint replacements were demonstrated by immunohistochemistry on tissue sections. Other markers for the characterization of macrophages, B cells, T cell subpopulations, @entity3647 and HLA-DR antigens were also used. The 10 cases examined showed excessive metallosis within the cytoplasm of the macrophages and extracellular matrix. @entity1356 containing cells were found in seven cases, four of which showed positive staining on more than 80% of the macrophages. A relatively similar proportion of T cells was seen in all the cases. T helper ( @entity404 positive) cells were always present in excess of T suppressor ( @entity405 positive) subtype. T cells showed no expression of detectable membrane @entity3647 . No B cells were found in these cases. Macrophages showed very strong immunostaining for HLA-DR. These findings indicate the possible induction of @entity1356 production by activated macrophages in the interface in response to the presence of metallic wear debris. In view of the well known effect of @entity1356 as a potent mediator of bone lysis, the results suggest a major role of the metal debris-containing macrophages in the process of @entity3061 and subsequent implant loosening.
