Table II.

In vitro effect of CTLA-4 blockade on the suppressive function of CD4+CD25+ cellsa

No anti-CTLA-4100 μg/ml anti-CTLA-4
Counts per minute ± SEM
Accessory cells103 ± 17101 ± 12
CD255936 ± 11303708 ± 1592
CD25+330 ± 25356 ± 77
1:12608 ± 6861890 ± 489
% suppression62%59%
  • a The effect of CTLA-4 blockade on CD4+CD25+ cell inhibition of CD4+CD25 cell proliferation was measured in a suppression assay. Cell populations were cocultured in a 1:1 ratio for 5 days and pulsed with [3H]thymidine 18 h prior to harvest in representative patient F.