CD4 and systemic lupus erythematosus: Increased proportions of pro-atherogenic CD16+ monocytes, low-density granulocytes (LDG), Th17 cells and senescent CD4+CD28null lymphocyte subsets, along with reduced numbers of vascular repairing endothelial progenitor cells (EPCs) and angiogenic T cells, all contribute jointly to the development of atheromatosis in SLE patients.