title: Long-term implanted cOFM probe causes minimal tissue reaction in the brain.
abstract: This study investigated the histological tissue reaction to long-term implanted cerebral open flow microperfusion (cOFM) probes in the frontal lobe of the rat brain. Most probe-based cerebral fluid sampling techniques are limited in application time due to the formation of a glial scar that hinders substance exchange between brain tissue and the probe. A glial scar not only functions as a diffusion barrier but also alters metabolism and signaling in extracellular brain fluid. cOFM is a recently developed probe-based technique to continuously sample extracellular brain fluid with an intact blood-brain barrier. After probe implantation, a 2 week healing period is needed for blood-brain barrier reestablishment. Therefore, cOFM probes need to stay in place and functional for at least 15 days after implantation to ensure functionality. Probe design and probe materials are optimized to evoke minimal tissue reaction even after a long implantation period. Qualitative and quantitative histological tissue analysis revealed no continuous glial scar formation around the cOFM probe 30 days after implantation and only a minor tissue reaction regardless of perfusion of the probe.
authors.affiliation: HEALTH - Institute of Biomedicine and Health Sciences, JOANNEUM RESEARCH, Graz, Austria.
authors.forename: Thomas
authors.initials: T
authors.lastname: Birngruber
authors.affiliation: Division of Endocrinology and Metabolism, Medical University of Graz, Graz, Austria.
authors.forename: Arijit
authors.initials: A
authors.lastname: Ghosh
authors.affiliation: Division of General Neurology, Medical University of Graz, Graz, Austria.
authors.forename: Sonja
authors.initials: S
authors.lastname: Hochmeister
authors.affiliation: Institute of Pathology, Medical University of Graz, Graz, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Asslaber
authors.affiliation: HEALTH - Institute of Biomedicine and Health Sciences, JOANNEUM RESEARCH, Graz, Austria.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kroath
authors.affiliation: HEALTH - Institute of Biomedicine and Health Sciences, JOANNEUM RESEARCH, Graz, Austria; Division of Endocrinology and Metabolism, Medical University of Graz, Graz, Austria.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Pieber
authors.affiliation: HEALTH - Institute of Biomedicine and Health Sciences, JOANNEUM RESEARCH, Graz, Austria; Division of Endocrinology and Metabolism, Medical University of Graz, Graz, Austria.
authors.forename: Frank
authors.initials: F
authors.lastname: Sinner
mesh_terms: D000818:Animals; D001812:Blood-Brain Barrier / Q000166:cytology / Q000378:metabolism; D001921:Brain / Q000166:cytology* / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000378:metabolism; D004567:Electrodes, Implanted / Q000009:adverse effects*; D005625:Frontal Lobe / Q000166:cytology / Q000378:metabolism; D005904:Glial Fibrillary Acidic Protein; D008297:Male; D008840:Microfilament Proteins / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism; D010477:Perfusion / Q000295:instrumentation*; D011474:Prosthesis Design; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
chemical_list: C491049:Aif1 protein, mouse; D002135:Calcium-Binding Proteins; D005904:Glial Fibrillary Acidic Protein; D008840:Microfilament Proteins; D009419:Nerve Tissue Proteins; C528900:glial fibrillary astrocytic protein, mouse