Mononuclear cells from peripheral blood (A and B) and inguinal lymph nodes (C) were isolated and assessed for presence of measles virus (MeV) N gene RNA by qRT-PCR (A and C) or ddRT-PCR (B). (A) MeV N gene RNA was quantified in total PBMCs and isolated CD3+ T cells from 4 individual animals (15U, 46U, 67U, 40V). (B) MeV N gene RNA was quantified in quadruplicates by ddRT-PCR in PBMCs collected from Y monkeys 14–60 and 75–90 days after infection that had been sorted into CD3+ (n = 11; n = 4, respectively) and CD20 (n = 4; n = 2 respectively) subsets. (C) MeV N gene RNA was quantified in duplicate by qRT-PCR in lymph node cells collected from Y monkeys 71 and 154 days after infection that had been sorted into CD3+, CD20+ (n = 4 at 71 days after infection), and CD14+ subsets. Numbers of animals studied vary between assays because sufficient cells were not available to perform all assays on all animals. Data are presented as (copies of MeV-N/copies of GAPDH) × 5000 for individual animals in dot plots with mean ± SD indicated.