PBMC Proliferation assay. CFSE-labeled PBMCs were stimulated with a panel of anti-CD3 for 5 days. A representative experiment of 3 is shown in a–f. (a) unstimulated PBMCs, (b) monovalent 1DDantiCD3 stimulated PBMCs, (c) divalent CSANs stimulated PBMCs, (d) octavalent CSANs stimulated PBMCs, (e) UCHT-1 F(ab')2 stimulated PBMCs, (f) UCHT-1 stimulated PBMCs.