sCD28, sCD80, sCTLA-4, and sBTLA Are Promising Markers in Diagnostic and Therapeutic Approaches for Aseptic Loosening and Periprosthetic Joint Infection. - Jubel JM; Randau TM; Becker-Gotot J; Scheidt S; Wimmer MD; Kohlhof H; Burger C; Wirtz DC; Schildberg FA (Frontiers in immunology, 2021)