A recent phase II clinical trial enrolled a total of 27 septic shock patients with severe lymphopenia and these patients were treated with recombinant IL-7 to treat sepsis; dynamic monitoring of lymphocyte count and lymphocyte subpopulations during IL-7 treatment found that absolute lymphocyte counts as well as circulating CD4+ and CD8+ T cell counts increased by more than threefold over baseline after IL-7 treatment [97]. Here, CD4 is linked to lymphopenia.