Regulation of Interleukin (IL)-18 Receptor Chain Expression on CD4+ T Cells during T Helper (Th)1/Th2 Differentiation: Critical Downregulatory Role of IL-4 Regulation of Interleukin (IL)-18 Receptor Chain Expression on CD4+ T Cells during T Helper (Th)1/Th2 Differentiation: Critical Downregulatory Role of IL-42018-01-17T17:05:23-05:00