Challenges and Opportunities in Detecting In Vivo Peptide and Protein Chemical Communication

by Stenken, Julie A.; Fletcher, Heidi J.; Duo, Jia; Wang, Ying

Microdialysis sampling is a widely used and successful sample collection method to obtain anal.-clean samples from complex matrixes. A major application of microdialysis sampling has been to collect important chem. communication mols. such as the hydrophilic neurotransmitters dopamine, glutamate, and serotonin in the brain. Over the last few years our group has focused on applying microdialysis sampling towards measuring different endogenous components related to wound healing. This work initially focused on cytokine collection, but led to an interesting spin-off project in neuropeptide detection. We have also embarked on using mass spectrometry to identify the presence of important matrix remodeling proteins, the matrix metalloproteinases (MMPs). This talk will highlight several of the fundamental parameters that must be considered when collecting proteins and peptides with microdialysis sampling during a long-term implantation. Recent progress with protein affinity-capture using both antibodies and heparin during microdialysis sampling will be presented. Updated progress with in vivo MMP detection and how the localized inflammatory response affects probe calibration for small mols. will also be discussed. Support for this work comes from NIH grants EB-001441 and DA-020577.