Fig. 3.
TLR8 stimulation enhances cetuximab-mediated ADCC of HNC cells in all FcγRIIIa-158 V/F genotypes. PBMC were incubated with TLR8 selective agonist VTX-2337 (250 nM) or with media for 18 h and then co-cultured at E:T = 50:1 for 4 h with 51Cr labeled UM-22B or PCI-15B HNC cells coated with cetuximab (10 μg/mL). Genomic DNA was extracted from PBMC, and FcγRIIIa-158 V/F genotype was determined using a PCR SNP assay. TLR8 stimulation of PBMC enhanced specific lysis of cetuximab-coated UM-22B and PCI-15B HNC cell targets: FF (p < 0.001), VF (p < 0.001), VV (p < 0.05). *p < 0.05, ***p < 0.001 (C225:Cetuximab VTX:VTX-2337)