In HC, DN B cells showed a positive correlation with a few of the early differentiated CD4 subsets, namely CD4CD45RA+CD57- and CD4CD28+CD57-, while in SLE patients, almost all early differentiated CD4 subtypes had a significant positive correlation with DN B cells, RTEs, and all subtypes lacking CD57 and expressing CD28 on their membrane. This evidence concerns the gene CD28 and systemic lupus erythematosus.