Quantification of Human Mabs in Mouse Tissues Using Generic Affinity Enrichment Procedures and LC-MS Detection.

BACKGROUND:The disease state can modulate the penetration of large antibody-sized therapeutic molecules into affected tissues. Suitable bioanalytical methods are required for the quantitative analysis of drug tissue levels to enable a better understanding of the parameters influencing drug penetration and target engagement.RESULTS:Described is a sensitive and selective LC-MS/MS assay for the quantification of human mAb molecules in mouse tissues. By homogenizing tissues directly into serum, a common serum calibration curve can be used for multiple tissues. A generic procedure was used for affinity enrichment. An analytical range of 20 - 20,000 ng/ml was achieved in serum.CONCLUSION:The method described here can be applied for the quantitative analysis of mAb and Fc-fusion therapeutic molecules in a variety of animal tissue matrices.