Synthetic Cells Elicit Immune Response For Cancer

Vaccines that stimulate the immune system to treat cancer usually address dendritic immune cells, which in turn activate T cells. Alan E. Rowan, Kerstin Blank, Carl G. Figdor, and coworkers at Radboud University, in the Netherlands, have come up with polymer-based synthetic dendritic cells that activate T cells directly (ACS Chem. Biol. 2014, DOI: 10.1021/cb500455g). The synthetic dendritic cells are made of a semiflexible poly(isocyano peptide) scaffold decorated with multiple copies of two antibodies needed to activate T cells. Thanks to the flexibility of the scaffold, the polymer-bound antibodies move around and cluster together, enabling multivalent binding similar to that of natural dendritic cells. The synthetic dendritic cells activate desirable helper, memory, and especially killer subtypes of T cells, but not undesirable regulatory T cells, which can counteract the function of the killer cells. Compared with versions having only one of the antibodies, the synthetic dendritic cells are better able to activate multifunctional killer T cells.