Interaction of a triantennary quinoline glycoconjugate with Asialoglycoprotein receptor.

Targeted intracellular delivery is an efficient strategy for developing therapeutics against cancer and other intracellular infections. Non-specific drug delivery show limited clinical applications owing to their high dosage, cytotoxicity, non-specific action, high cost, etc. So, targeted delivery of less cytotoxic drug candidates to hepatocytes through ASGPR mediated endocytosis could be an efficient strategy to surmount the prevailing shortcomings. In the present work, the gene encoding ASGPR-H1-CRD has been amplified from Huh7 cells, cloned into pET 11a vector and the ASGPR-H1-CRD protein was expressed and purified from E. coli . A novel triantennary galactose conjugated quinoline derivative 4 has been synthesized that demonstrates a 17 fold higher binding affinity to isolated ASGPR-H1-CRD protein receptor (K d ~ 54 µM) in comparison to D-Galactose (Kd ~ 900 µM). Moreover, micro-calorimetric studies for the interaction of glycoconjugate 4 with ASGPR protein on live hepatocytes showed notable thermal response in case of ASGPR containing Huh7 cells, in comparison to non-ASGPR Chang cells. Our research outcome might serve as an approach towards targeted delivery of small glycoconjugates to hepatocytes.