GZMB and plasma cell myeloma: In this case, the surface of reduction-responsive chimaeric polymersomes were decorated with hyaluronic acid – a natural polysaccharide with selective binding affinity to myeloma with over-expressed CD44 receptors.385–389In vitro, these granzyme B-loaded polymersomes had a low IC50 of 8.1 nM and, in comparison to free DOX, proved to be at least 100-fold more potent.390 Moreover, further in vivo studies with mice bearing orthotopic human LP1 myeloma cells showed a 2.5-fold greater uptake at the tumour site than in clearing organs, such as the spleen and the liver.