CCR5 and infection: Using this approach, the authors successfully introduced an shRNA construct targeting a tat/rev exon, a TAR decoy that localized to the nucleolus, and a CCR5-targeting ribozyme into human HSCs ex vivo using a lentiviral vector, and showed that the cells expressing the construct—dubbed Triple-R—were protected from infection in vitro and provided protection from infection in a humanized mouse model of HIV infection.