Fig. 3: Targeting strategies and specificity of DIRECTED.
From: Cell type-specific delivery by modular envelope design
a (Top) Schematic representation of antibody-tethering strategies and (bottom) relative transduction efficiency of Jurkat+surface-HA cells sorted into four bins of different expression levels (low, medium low, medium high, high) or WT cells (no) using DIRECTED lentiviral particles with the scFv strategy (left), the pAG strategy (middle), or the SNAP strategy (right, with excess antibody or after removal of excess antibody) targeting surface-HA (N = 4 for each condition). b (Top) Representative microscopy images of HEK293FT cells engineered to express different synthetic surface receptors (surface-HA, surface-Spot, surface-Strep, and surface-V5) after delivery of an H2B-mCherry transgene using pAG-DIRECTED lentiviral particles with the indicated targeting antibodies (no antibody, αHA, αSpot, αStrep, and αV5). (Bottom) Transduction efficiency (as a percentage of mCherry+ cells) for the synthetic cell lines with the indicated targeting antibodies at different MOI (N = 4 for each condition). c (Top) Representative microscopy images of the same cell lines as in (b), using SNAP-DIRECTED lentiviral particles in the presence of an excess of the indicated BG-labeled targeting antibodies (no antibody, αHA-BG, αSpot-BG, αStrep-BG, and αV5-BG) at different MOI. (Bottom) Transduction efficiency (as a percentage of mCherry+ cells) for the synthetic cell lines with an excess of the indicated targeting antibodies at different MOI (N = 4 for each condition). Data are presented as the mean with the error bars indicating the sample standard deviation. Source data are provided as a Source Data file. For panel (a) a two-sided Welch’s t-test with Bonferroni correction was used. p-values sc-Fv strategy 3.52E-06, 0.000116, 0.000242, 0.032; pAG strategy—no antibody 0.368, 0.3, 1, 0.472; pAG strategy—αHA 0.0001224, 0.0001236, 0.00026, 0.016; SNAP strategy (excess antibody)—no antibody 0.524, 1, 1, 1; SNAP strategy (excess antibody)—αHA-BG 1.55E-05, 1.50E-06, 6.08E-08, 3.77E-07; SNAP strategy (excess antibody removed)—no antibody 1, 0.06, 1, 1; SNAP strategy (excess antibody removed)—αHA-BG 0.000412, 0.000384, 0.068, 1. [ns, not significant; *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001; scale bar is 100 µm; SecSig secretion signal, TM transmembrane domain].
