RAG1 and Hypertension: Some studies (26, 28) revealed that mice lacking CD8+ T cells, not CD4+ T cells blunt Ang II-induced BP elevation, and transfer of CD8 but not CD4+ T cells into Rag1-deficient animals re-establish the hypertensive response to chronic angiotensin II infusion, suggesting that CD8 T cells may be necessary for hypertension.