By contrast, abrogation of the long-lasting (6 months) increase in CD4+CD25+ Treg observed in irradiated lungs of C57BL/6 mice by long-term CD4+CD25+ T cell depletion with an anti-CD25 antibody reduced the increase in fibrocytes and attenuated radiation-induced lung fibrosis (80). The gene discussed is CD4; the disease is pulmonary fibrosis.