sanctuary cell
n.— «Back in 1996, when “cocktails” of antiretroviral drugs were proved effective, some researchers proposed that all cells harboring HIV might eventually die off, leading to eradication of HIV from the body—in short, a cure. Those hopes foundered on the discovery that HIV, which integrates itself into a patient’s own DNA, hides in so-called “sanctuary cells,” where it lies dormant yet remains capable of reigniting an infection.» —“A Doctor, a Mutation and a Potential Cure for AIDS” by Mark Schoofs Wall Street Journal Nov. 7, 2008. (source: Double-Tongued Dictionary)