interleukin-12 (il-12) is a key cytokine involved in regulating the balance between th1 and th2 cells by promoting th1 response. a reduced capacity to produce this cytokine could lead to aberrant th2 development. on the same aspect significant impact of il-12 on invariant natural killer t (inkt) cells was reported. therefore, we examined the serum levels of il-12 and the absolute number of peri...