Fig. 5: pAPCs obviate avidity-specificity trade-off associated with pMHC-functionalized capture probes.
A Schematics illustrating dynabeads functionalized with varying pMHC densities (2–2 × 104 pMHCs/µm2) and pAPC. B Flow cytometric characterization of streptavidin-functionalized dynabeads conjugated with different densities of biotin-SIINFEKL-H-2Kb monomers using anti-H2-kb-SIINFEKL antibodies. C Protein quantification characterizing pMHC content on dynabeads using micro BCA assay. P values, ****p < 0.0001 (Independent biological replicates n = 5). D Examination of T cell recovery by different capture probes in a CD8+ T cell pool containing 10% of cognate T cells. 106 T cells containing 105 OT-I T cells were incubated with 106 pAPCs or 5 × 107 dynabeads of equivalent total surface area for 2 h prior to T cell isolation and enumeration (Independent biological replicates n = 4). E Quantification of OT-I T cells recovery by the different capture probes (Independent biological replicates n = 4). F Enrichment fold for cognate OT-I T cells following pAPC or dynabeads isolation. P value from left to right, ****p < 0.0001 **p = 0.007, *p = 0.0141, ***p = 0.0006, ****p = 0.0001 (Independent biological replicates n = 4). G Examination of T cell recovery by different capture probes in a CD8+ T cell pool containing 0.1% of cognate T cells. 106 of T cells containing 103 OT-I T cells were incubated with 106 PAPCs or 5 × 107 dynabeads of equivalent total surface area for 2 h prior to T cell isolation and enumeration (Independent biological replicates n = 4). H Quantification of OT-I T cells recovery by the different capture probes (Independent biological replicates n = 4). I Enrichment fold for cognate OT-I T cells following pAPC or dynabeads isolation. P value from left to right, **p = 0.0031, **p = 0.0012, **p = 0.0053, ***p = 0.0003, ***p = 0.0002 (Independent biological replicates n = 4). The error bars represent mean ± standard deviation. Statistical analyses were performed by two-sided Student’s t tests.
