Table 1

Apoptosis in rabbit TGs. Rabbits were infected with wild-type HSV-1 McKrae, dLAT2903 (LAT ), or dLAT2903R (LAT +) in both eyes (2 × 105 plaque-forming units per eye), as described (3). On the days indicated after infection, two rabbits were killed per group. TGs were harvested and sectioned, and five sections per TG (20 sections per group at each time point) were stained by the TUNEL assay that detects DNA ends produced during apoptosis (Klenow-FragEL DNA fragmentation detection kit; Oncogene, Cambridge, MA) as described by the manufacturer. Sections were read by light microscopy by two individuals who had no knowledge of the groups and were considered positive for apoptosis if one or more neurons were clearly positive. A TG was considered positive if one or more of its sections were positive. For each TG, the sections used were obtained from different areas spanning the TG.

Criterion Day 3 Day 7 Day 10 Day 14
Sections with apoptotic neurons (%)
dLAT2903 5 7010 5
dLAT2903R 0 0 20 5
McKrae0 0 0 0
TGs with apoptotic neurons (%)
dLAT2903 0 100 2525
dLAT2903R 0 2525 25
McKrae 0 0 0 0