The targeting of 14-succinate triptolide-lysozyme conjugate to proximal renal tubular epithelial cells

We have synthesized a renal-specific drug carrier, 14-succinyl triptolide-lysozyme (TPS-LZM) conjugate for targeted delivery of TP to the PTECs. TPS-LZM could be taken up by HK-2 cells, free TP would be degraded and released, mainly from basolateral side of the cells. Compared with TP, the overall targeting efficiency (TE) of TPS-LZM was significantly enhanced from 11.74% to 95.54% and its MRT was moderately prolonged from 3.08 h to 4.10 h. At very low concentration, TPS-LZM could significantly reverse the disease progression in renal ischemia-reperfusion (I/R) injury animal models, while the mixture of free TP and LZM was ineffective. Further, TPS-LZM conjugate presented much lower hepatotoxicity (0.78 folds lower than TP) and no adverse effect on the immune (1.13 folds higher than TP) and genital system. Thus, TPS-LZM represents a very effective drug candidate for specific treatment of immunological renal diseases with low adverse side effect.