Expression of caspase-1 in synovial membrane-like interface tissue around loosened hip prostheses

Autor: Yrjö T. Konttinen, Mikko Liljeström, Mika Hukkanen, J. Westerlund, Jami Mandelin, Seppo Santavirta, T. Paavilainen, Tian-Fang Li
Rok vydání: 2002
Předmět:
Zdroj: Rheumatology International. 22:97-102
ISSN: 1437-160X
0172-8172
DOI: 10.1007/s00296-002-0197-8
Popis: Caspase-1 expression in synovial membrane-like interface tissue (SMLIT) around loosened hip prostheses and osteoarthritic synovial samples was studied. Caspase-1 mRNA was found in SMLIT and synovial tissue. There is no difference in the copy numbers of caspase-1 mRNA between these samples. Both precursor and active forms of caspase-1 proteins appeared in these samples, but the number of positive cells was higher in SMLIT than in synovial tissue. Double labeling revealed that most caspase-1-positive cells were macrophages and fibroblasts. In the lining-like layers and deep stroma of SMLIT, many cells were double positive for active caspase-1 and interleukin-1 beta (IL-1beta). In contrast, the number of active caspase-1/IL-18 double-positive cells was very low. We conclude that caspase-1 synthesis is increased in SMLIT. Caspase-1 can be involved in implant loosening by processing IL-1beta precursor into its mature form, which is a potent osteoclast-activating factor and a major proinflammatory mediator.
Databáze: OpenAIRE