ATRA does not affect apoptosis of HDM-expanded Th2 cells. CTV labeled PBMCs from allergic asthmatic subjects were cultured with HDM Ag for 7d with ATRA or DMSO vehicle control. Annexin V staining was measured in the CTVlow (unprolferated) and CTVhigh (proliferated HDM Ag specific) cells, after first gating on CD4+, 7AAD- lymphocytes. Above, data from a representative experiment. Below, combined results from 3 independent experiments. The percentage and number of annexin V positive cells are plotted. No statistical differences were observed by Student’s t test.