Immune responses in patients with metal-on-metal hip articulations: a long-term follow-up.
Metal-on-metal (MoM) hip bearings are being inserted into ever-younger patients. The effects on the immune system of chronic exposure are unknown. We investigated the immune response of patients with MoM hip bearings. In patients with MoM implants, the expression of antigen-presenting cell (APC) surface molecules (CD86 and HLA-DR) was seen to be significantly higher (P < .05) than control group. High levels of APC surface molecules suggest an activated state and attempts to propagate an immune response. However, in the same group, the expression of T-cell markers (CD3 and CD28) was low, indicating a small T-cell population. This suggests, despite the activation of APCs, that T cells down-regulate immune responses in MoM articulations. Conversely, in metal-on-polyethylene articulations, expression of T-cell molecules was elevated and expression of APC molecules lowered.
Royal National Orthopaedic Hospital, London, United Kingdom.
Paul M
PM
Whittingham-Jones
Edward
E
Dunstan
Huwaidha
H
Altaf
Stephen R
SR
Cannon
Peter A
PA
Revell
Timothy W R
TW
Briggs
D000293:Adolescent; D000328:Adult; D000368:Aged; D000938:Antigen-Presenting Cells / Q000276:immunology; D019644:Arthroplasty, Replacement, Hip; D051940:B7-2 Antigen / Q000097:blood; D018106:CD28 Antigens / Q000097:blood; D017252:CD3 Complex / Q000097:blood; D005500:Follow-Up Studies; D006684:HLA-DR Antigens / Q000097:blood; D006621:Hip Joint / Q000276:immunology / Q000601:surgery; D006622:Hip Prosthesis; D006801:Humans; D007107:Immune System / Q000502:physiology*; D008137:Longitudinal Studies; D008670:Metals; D008875:Middle Aged; D013601:T-Lymphocytes / Q000276:immunology; D055815:Young Adult
D051940:B7-2 Antigen; D018106:CD28 Antigens; D017252:CD3 Complex; D006684:HLA-DR Antigens; D008670:Metals