Table I.

Impact of increased antigen-specific CD4+ or CD8+ precursor frequencies on the requirement for CD28/CD154-mediated costimulation during skin graft rejectiona

Frequencyb (no. c) of CD8+ cells
Frequency (no.)
 of CD4+ cellsFrequency (no.)1 in 106 (None)0.05% (105)0.5% (106)5% (107)
1 in 106 (None)>150 d>150>150>150
0.05% (105)>150>150>150>150
0.5% (106)>150>150>130.7 ± 6817.2 ± 4.7
5% (107)>150>150>15013.8 ± 1.2
  • a B6 mice received the indicated number of OT-I or OT-II T cells and an mOVA skin graft 48 h later. All mice were treated with CTLA-4 Ig and anti-CD154 mAbs as described in Materials and methods.

  • b Resulting frequency after adoptive transfer of exogenous T cells.

  • c Absolute number of adoptively transferred OT-I or OT-II T cells.

  • d Data is expressed as the mean survival time (in days) ± SEM of 10 mice per group.