Task: Named Entity Recognition
Input (English):  Although interleukin ( IL ) - 12 and IL - 4 polarize naive CD4 ( + ) T cells toward T helper cell type 1 ( Th1 ) or Th2 phenotypes , it is not known whether cytokines instruct the developmental fate in uncommitted progenitors or select for outgrowth of cells that have stochastically committed to a particular fate .
Output (English): IL - 4