CD44 and hyperinsulinemic hypoglycemia, familial, 4: Next, we assessed whether intrarenal Treg develops typical phenotypic alterations that are associated with IL-2 deficiency during progression of LN, such as reduced expression of the IL-2 receptor α-chain, i.e., CD25, and increased expression of CD44 and CD69 as previously observed in the lymphatic organs and peripheral blood of these mice [14].