Individual Risk Factors for Enhanced Inflammation to Arthroplasty Wear Particles: Analysis of Cytokine Polymorphisms and in Vitro Cytokine Production to Wear Particles (Ceramic, Metal, XPE)

A cytokine polymorphism analysis in 100 individuals with aseptic implant intolerance reaction (patients of the implant allergy special ambulance) and in 100 asymptomatic patients with implanted endoprostheses will be done. Furthermore, supplementary clinical data (such as type of implant, hospital stay, discomfort), questionnaire-based history and a clinical score (WOMAC score) are recorded. In the subgroup analysis in 10 patients of implant patients with complaints with special found cytokine polymorphisms and 10 implant patients without problems the cytokine response to particles in vitro will assessed.

Test parameters:

1. total collective:

the DNA of cryopreserved blood sample will be isolated. By polymerase chain reaction, four different known polymorphisms will be analyzed, three IL-1B genes (IL-1B-3954 IL-1B-31, and IL-1B-511), and a IL-1ß receptor antagonist gene (IL -1-RN, intron 2 VNTR). Molecular analysis includes DNA isolation, polymerase chain reactions (PCR) and gel electrophoresis. 2. Subgroup analysis:

Peripheral blood cells will be isolated from 10 implant patients with complications and 10 symptom-free persons and stimulated in cell culture with control stimuli, the IL-1ß-inducer lipopolysaccharide (LPS) and ceramic particles (BIOLOX delta)*, CoCrMo particles and XPE-particles** cultured separately or in combination. The secretion of IL-1ß and selected proinflammatory cytokines will be measured. The methods include cell isolation by density centrifugation and analysis of cell culture supernatants by a multiplex cytokine measurement assay by flow cytometry.