Fig 1.

Ad26 uses CD46 and not CAR as a primary cellular receptor. Ad5, Ad26, and Ad35 vectors expressing enhanced green fluorescent protein (eGFP) were incubated with mouse or human cells for 24 h, and the expression of eGFP was evaluated by flow cytometry. (A) PBMC from wild-type mice (WT) and CD46 transgenic mice (CD46) were infected with Ad vectors at multiplicities of infection (MOIs) of 0, 10², 10³, and 10⁴ (left). PBMC from CD46 transgenic mice were preincubated with the anti-CD46 MAb 13/42 at concentrations of 0, 0.04, 0.4, or 4 μg/ml for 1 h and then infected with Ad vectors at an MOI of 10³ (right). (B) Human PBMC were preincubated with the anti-CD46 MAb 13/42 and then infected with Ad vectors at an MOI of 10³. CD11c and CD123 were utilized to identify myeloid dendritic cell (mDC) and plasmacytoid dendritic cell (pDC) subpopulations. Panels A and B show representative data of two experiments. (C) Human PBMC were preincubated with the anti-CAR MAbs (RmcB, E1-1), the anti-CD46 MAbs (13/42, M177, MEM-258), or an isotype control MAb and were then infected with Ad26 at an MOI of 10³. Mean and standard error of the mean are shown from 4 independent experiments. *, P < 0.01, one-way ANOVA with Dunnett's posttest.