Though immune cells have the capabilities to kill cancer cells, they’re often thwarted by cancer’s ability to evade detection. Researchers at Pennsylvania State University have now developed engineered natural killer cells that have a much better ability to find and kill cancerous cells. “We explored a novel method to engineer natural killer cells,” said Yong Wang, professor of biomedical engineering and one of the developers of the new approach, in the announcement. “This technique significantly improved the recognition and killing of target cancer cells.” Wang and team developed molecular add-ons for white blood cells called polyvalent antibody mimics (PAMs). These PAMs are structured from DNA to produce a scaffold that features multiple branches. Each of these branches has a molecule at the tip that is attracted to a specific tumor marker of interest. Similar approaches have been tried, but the novel development in this research of having multiple branches has resulted in a much greater affinity of the modified immune cells for their targets. Moreover, the engineered white blood cells seem to be more deadly for the cancer cells that they find. Additionally, the new technique is nowhere near as expensive to put in practice compared with conventional genetic engineering approaches for cell-based therapies. Yet, it is compatible with those existing techniques and only takes a few hours of prep time. “The enhanced efficiency of PAM-engineered immune cells will reduce the doses of cells needed for immunotherapy, thereby further decreasing the manufacturing time and cost,” added Wang. From the study abstract in Angewandte Chemie International Edition: We present a synthetic method for functionalizing the surface of natural killer (NK) cells with a supramolecular aptamer‐based polyvalent antibody mimic (PAM). The PAM is synthesized on the cell surface through nucleic acid assembly and hybridization. The data show that PAM has superiority over its monovalent counterpart in powering NKs to bind to cancer cells, and that PAM‐engineered NK cells exhibit the capability of killing cancer cells more effectively. Notably, aptamers can, in principle, be discovered against any cell receptors; moreover, the aptamers can be replaced by any other ligands when developing a PAM. Thus, this work has successfully demonstrated a technology platform for promoting interactions between immune and cancer cells. Source
