Irradiation Prevents Mice from Generating Their Own T Cells

question 31

Multiple Choice

Irradiation prevents mice from generating their own T cells.When the immune systems of irradiated mice are reconstituted with unfractionated CD4 cells,the recipients show no signs of autoimmune disease.However,if the T cells are depleted of the CD4+CD25+ subset prior to transfer,recipients show multi-organ autoimmunity.This result demonstrates the role of _____ in suppressing autoimmunity.

• A)cytotoxic T cells
• B)helper T cells
• C)regulatory T cells
• D)all of the above