DEAE dextran and spinoculation enhance infection for CD4+ T-cells but not for MDDCs. Infection in the presence and absence of DEAE dextran and spinoculation on CD4+ T-cells (A) and MDDCs (B). DEAE dextran and spinoculation enhance non-mac-tropic Envs and mac-tropic Envs to similar extents (C). Significant differences were evaluated using Mann Whitney or Wilcoxon matched pair tests as described in Materials and Methods. Figure 3 experiments were done in conjunction with the direct infections shown in Figure 2. Figure 3 data for infection without DEAE dextran and spinoculation is therefore the same as that shown in Figure 2. Only the p values relevant for DEAE dextran and spinoculation that show significance are shown. Symbol colour designations are the same as described in Figure 1. Please also refer to Additional file 1: Figure S4, where FFU/ml for each Env+ pseudovirus is presented in a bar graph with standard deviation bars shown, while the column scatter plot of infectivity as a percent of TZM-bl infectivity is presented with each point labeled for Env used. Median values are marked.