The invention relates to methods for modulating the immune function through targeting of CLIP molecules as well as gamma delta T cells. The result is wide range of new therapeutic regimens for treating, inhibiting the development of, or otherwise dealing with, a multitude of illnesses and conditions, including autoimmune disease, transplant and cell graft rejection, cancer, bacterial infection, HIV infection, and AIDS, as well as novel methods of diagnosis and of introducing a treatment regimen into a subject.