title: Elastase activity, uninhibited by alpha 1-antitrypsin, in the periprosthetic connective matrix around loose total hip prostheses.
abstract: To clarify the proteolytic cascade in the loosening of total hip prostheses, the presence, tissue localization, and content of the serine proteinase, elastase, and its endogenous inhibitor, alpha 1-antitrypsin, were studied in periprosthetic tissues around 12 loose hip prostheses by immunohistochemistry, spectrophotometric enzyme assay, and immunoblot analysis, and the results were compared with those in control synovial tissue samples from eight knees. Increased numbers of elastase-immunoreactive cells and elevated elastase activity, inhibited by the addition of native alpha 1-antitrypsin, were observed both in the interface tissues between the bone and implants and in the pseudocapsular tissues from around loose hip prostheses. Elevated elastase activity, uninhibited by alpha 1-antitrypsin in situ and inhibited by the addition of native inhibitor, suggests a proteinase-inhibitor imbalance that contributes to the weakening of periprosthetic tissues and thus causes the loosening of hip prostheses.
authors.affiliation: Department of Anatomy, University of Helsinki, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Takagi
authors.forename: Y T
authors.initials: YT
authors.lastname: Konttinen
authors.forename: S
authors.initials: S
authors.lastname: Santavirta
authors.forename: P
authors.initials: P
authors.lastname: Kangaspunta
authors.forename: T
authors.initials: T
authors.lastname: Sorsa
authors.forename: M
authors.initials: M
authors.lastname: Yamakawa
authors.forename: A
authors.initials: A
authors.lastname: Suda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003240:Connective Tissue Diseases / Q000201:enzymology / Q000473:pathology / Q000517:prevention & control*; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D015151:Immunoblotting; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D007719:Knee Joint / Q000187:drug effects / Q000201:enzymology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010196:Pancreatic Elastase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011475:Prosthesis Failure; D013053:Spectrophotometry; D013583:Synovial Membrane / Q000187:drug effects / Q000201:enzymology* / Q000473:pathology; D000515:alpha 1-Antitrypsin / Q000378:metabolism* / Q000502:physiology
chemical_list: D000515:alpha 1-Antitrypsin; D010196:Pancreatic Elastase