CD244 and cyclic hematopoiesis: Third, IL-2 positively regulated (CD27 on IgD-CD38+ B cell) and (CD27 on switched memory B cell)/natural killer cell receptor 2B4 (CD244) and negatively regulated (CD33dim HLA DR+ CD11b - absolute count)/interleukin-1 (IL-18) and (CD28+ CD4-CD8-T-cell %T cell)/osteoprotegerin (OPG), thereby promoting the progression of CH.