%0 Journal Article %T CD16<sup>+</sup> Monocyte Subsets in Patients with Total Joint Arthroplasty %A David C. Markel %A Nancy M. Jackson %A Jeffrey C. Flynn %A Weiping Ren %J Open Journal of Orthopedics %P 211-227 %@ 2164-3016 %D 2017 %I Scientific Research Publishing %R 10.4236/ojo.2017.78023 %X Objective: There are two monocyte populations in human blood: CD14⁺CD16^- classical monocytes and CD14⁺CD16⁺ inflammatory monocytes. CD14⁺CD16⁺ inflammatory monocytes, account for approximately 10% of the total monocytes, may be expanded in various types of inflammatory conditions. The purpose of this study was to investigate whether the expansion of the CD14⁺CD16⁺ monocyte population represents a risk factor of aseptic loosening (AL). Methods: Peripheral monocytes subsets were measured in revision patients with AL (n = 35) and in patients with stable implants (SI, n = 56). The gene profiles of TNF¦Į, IL-1¦Ā, CD16, CD68 and TRAP5B from collected loosening periprosthetic tissues were analyzed. Results: There were no significant differences in the CD14⁺CD16⁺ monocyte populations between the SI and AL patients. The CD14⁺CD16⁺ monocytes were marginally higher in revision patients with osteolysis (n = 30), compared to patients without osteolysis (n = 5) though no statistically difference was found. There was an association between the CD14⁺CD16⁺ monocyte subpopulation and the tissue gene profiles, including IL-1¦Ā (p = 0.063), CD68 (p = 0.036), and TRAP5B (p = 0.073). Conclusion: It was demonstrated that the expansion of CD14⁺CD16⁺ monocytes reflects, to some extent, the inflammatory status of the loosening periprosthetic tissues. It is unclear if some of those SI patients (no pain and negative radiograph) who have a higher frequency of CD14⁺CD16⁺ monocytes may be at the early stage of AL. Further evaluation of CD14⁺CD16⁺ monocyte population, independently or combined with other factors, will be useful to design a risk profile for AL incidence and progression. %K Osteolysis %K Wear Debris %K CD14< %K sup> %K +< %K /sup> %K CD16< %K sup> %K +< %K /sup> %K Monocytes %K Aseptic Loosening %K AL %K Flow Cytometry %U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=77999