Moreover, some authors have underlined the presence of a negative correlation between B1 (IgM- and IgA-secreting CD19+ CD5+ cells, important to innate immunity procedures) and B2 (CD19+ CD5- cells that produce IgG and finally differentiate into PCs) cell counts and markers of CKD progression (such as serum creatinine -SCr- and blood urea nitrogen -BUN- values) in elderly individuals. The gene discussed is CD5; the disease is chronic kidney disease.