In vivo microdialysis studies of cytokines involved in the foreign body response at the biomaterial/tissue interface

by Wang, Xiangdan; Lennartz, Michelle R.; Loegering, Daniel J.; Stenken, Julie Ann


Implantation of biomaterials initiates the foreign body reaction which is mediated by various signaling mols. such as cytokines. Obtaining quant. information of these mols. is important to understand the whole process of the foreign body response. In this study, microdialysis sampling was used as a mean to study cytokines involved in foreign body response at the tissue/biomaterial interface, interleukin 6 (IL-6) was chosen as a representative cytokine in initial expts. Two microdialysis probes were implanted at dorsal s.c. space of rats. One probe was implanted for long term (3 or 7 days), and the other probe was acutely implanted on the day when microdialysis sampling was performed. After lipopolysaccharide injection, IL-6 recovery from the long-term probe was found to decrease dramatically compared to the acutely implanted probe. The decreased recovery was found mainly to be caused by tissue effects instead of membrane fouling. In order to test the possibility of cytokines elicited by implanted biomaterials, open ended tubes was used to collect interstitial fluid, and expt. data shows multiple cytokines detectable. Furthermore, our preliminary biomaterial data shows that it is promising to use microdialysis sampling to obtain cytokines information involved in the foreign body response. NIH EB001441 funds this work. on SciFinder(R)]