According to other researchers, a large number of additional parameters are related to a poorer humoral immunity activation, including increasing age [31,32,34], shorter duration between transplantation and vaccination (Ab acquisition is especially difficult during the first post-transplantation year), lower body mass index (BMI) [28], presence of anemia [27], female gender [26], diabetic nephropathy [32], deceased donor state, recent exposure to rituximab or antithymocyte globulin [34], and insufficient cellular response rate and IFN-γ production [35]. Here, IFNG is linked to anemia.