Based on the residues 131–151 at the same domain of this U1-70 k protein harboring the major epitopes as targets of autoreactive CD4 T cells in patients with lupus, the 21-mer synthetic peptide P140 was found protective in lupus-prone MRL-lpr mice and clinical trials by Muller and colleagues [9]. Here, CD4 is linked to systemic lupus erythematosus.