Figure 2.

Anatomic locations of viral nucleic acids within the spleen 3 d after infection with LCMV ARM 53b, Cl 13, and representative CTL⁻P⁺ (PBL 36-4, PBL 67-3, PBL 50-3, TNPBL4-2, and Mac 13-3) and CTL⁺P⁻ variants (TNB2-1 and TNB4-1) of ARM 53b. In situ hybridization was performed using a digoxigenin-labeled riboprobe specific for LCMV NP. In spleen sections from BALB/c ByJ mice infected intravenously with 2 × 10⁶ PFU of virus ARM 53b, TNB2-1, or TNB4-1, the nucleic acids localized predominantly in the red pulp (RP). Using identical conditions, the nucleic acids of CTL⁻P⁺ virus isolates localized within the white pulp (WP) or its marginal zone (MZ). All panels are shown at the same magnification. A higher power view is shown in the inset for ARM 53b– and Cl 13–infected mice. The arrows indicate viral nuleic acid detected in individual cells.