Viral RNA load in AS IL-4 DNA treated and untreated SHIV-infected macaques as seen by real-time RT-PCR and immunohistochemistry. (A) Viral RNA levels in the lungs (top), liver (middle), and spleen (bottom) in SHIV_89.6P-infected macaques (blue bars); viral RNA in infected macaques given a single dose of AS IL-4 (green bars); and viral RNA in the animals receiving 2 injections of the AS DNA (black bars). Viral gag mRNA/million HPRT ratios obtained after real-time RT-PCR are presented. RNA was extracted from 3 different regions of each tissue and analyzed individually. (B) p27 Staining in the spleen sections of control (top) and treated animals (bottom).