Red Cargo

Scientists from the Whitehead Institute for Biomedical Research have genetically and enzymatically modified red blood cells (RBC) to act as carriers of different payloads such as drugs, vaccines and imaging agents for delivery to specific locations across the body. RBCs were chosen by researchers for reasons including abundance and a long life span (up to 120 days in circulation).

During RBC production, the progenitor cells (cells that mature to different cell types) abandon their nuclei and all DNA therein. A mature RBC without DNA or nucleus lacks genetic material or earlier signs of genetic manipulation and could result in tumour or have other harmful effects. Scientists, therefore, genetically modified progenitor cells by introducing gene coding for a specific and slightly modified normal red cell surface. When RBCs mature, the proteins remain on the cell surface where they are modified by protein–labelling technique known as ‘sortagging’ that attaches various molecules to the cell and relies on a bacterial enzyme surface ‘sortase A’ to establish a strong chemical bond between the surface protein and molecule of choice without harming the cells and their surfaces. The longevity of the RBCs in the body enables neutralization of toxins by some antibodies.

Scientists proved the viability of this technique by using both, mouse and the human cells which may, in the near future, transform into a valid method for the delivery of the essential drugs through RBCs.