FIG. 6.

Cryopreserved mature DCs keep their phenotype and function. (A) Cryopreserved, mature DCs (MDC) (CB0507) were thawed and phenotypically compared to freshly matured DCs. The DCs were labeled with isotype controls and the indicated monoclonal antibodies. FACS histograms show profiles for isotype controls (gray areas with solid lines) and monoclonal antibodies (white areas with solid lines). The gates were set to include cells with large amounts of FSC and SSC. The data shown are representative of four experiments. (B) Freshly prepared and cryopreserved DCs (CB0507) were incubated for 1 h with 1 μg of tetanus toxoid/ml. Tetanus toxoid-pulsed DCs were added in graded doses to 2 × 10⁵ autologous T cells. After 5 days, T-cell proliferation was measured by [³H]thymidine incorporation. The results are expressed in counts per minute. One representative experiment of three is shown.