LV transduction of DCs and analysis of surface marker expression. PBMC-derived DCs were infected with LV on Day 5 (d5) and after maturation, co-cultured with naïve CD4 T cells for 1–2 weeks before intracellular cytokine staining (ICCS) and flow cytometry (FACS) analysis. The d5 DCs were transduced by LV-PLAP and 48 hr later, analyzed by PLAP enzyme assay. (B) FACS analysis of DC surface markers after viral transduction. The d5 DCs were transduced with LV carrying PLAP or Cre as reporter gene, MLV vectors, empty LV, or no vector controls (mock) and treated with TNF-α plus LPS. The cell surface markers were stained with antibodies and analyzed by FACS. The numbers represent mean fluorescence index (MFI) and the results are representatives of six experiments.