C Schmidt1, S Fabinyi2, S Rehfeldt1, S Klöpzig1, V Jentzen1, J Bohrisch1, A Messner2, J Storsberg3. 1. Fraunhofer-Institut für Angewandte Polymerforschung IAP, 14476, Potsdam-Golm, Deutschland. 2. HumanOptics AG, Erlangen, Deutschland. 3. Fraunhofer-Institut für Angewandte Polymerforschung IAP, 14476, Potsdam-Golm, Deutschland. joachim.storsberg@iap.fraunhofer.de.
Abstract
BACKGROUND: Intrastromal insertion of Krumeich's corneal ring between graft and residual host corneal tissue appears to impair preripheral, superficial and superfluous vascularization of donor corneal tissue. OBJECTIVES: The purpose of this study was to investigate the cytotoxic effects of Krumeich's ring using tissue cultures composed of primary human dermal microvascular endothelial cells from adult donors (HMVEC). MATERIALS AND METHODS: Soluble growth medium extracts of the individual components of Krumeich's ring alloy were prepared and HMVEC were exposed to these extracts in triplicate for 1 day followed by investigation with 3‑(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Furthermore, HMVEC were cultured for 5 days on either Krumeich's ring or polypropylene (PP) discs coated with individual components of the Krumeich's ring alloy followed by double vital staining with fluorescein diacetate (FDA) and propidium iodide (PI). RESULTS: The MTT assays revealed that higher doses of the extracts appeared to reduce the viability of HMVEC, while highly diluted extracts of molybdenum (Mo) powder appeared to increase the metabolic activity of HMVEC. The FDA-PI staining showed only a few live HMVEC on either cobalt (Co) or Mo-coated PP discs, compared to the respective titanium (Ti) and chromium (Cr) counterparts. Viable HMVEC appeared to attach to Krumeich's ring after a 5‑day incubation period. CONCLUSION: The results confirm that Krumeich's ring does not exert measurable cytotoxic effects in our chosen assay system. High dilutions of medium-soluble Mo powder extracts appear to increase the metabolic activity of HMVEC.
BACKGROUND: Intrastromal insertion of Krumeich's corneal ring between graft and residual host corneal tissue appears to impair preripheral, superficial and superfluous vascularization of donor corneal tissue. OBJECTIVES: The purpose of this study was to investigate the cytotoxic effects of Krumeich's ring using tissue cultures composed of primary human dermal microvascular endothelial cells from adult donors (HMVEC). MATERIALS AND METHODS: Soluble growth medium extracts of the individual components of Krumeich's ring alloy were prepared and HMVEC were exposed to these extracts in triplicate for 1 day followed by investigation with 3‑(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Furthermore, HMVEC were cultured for 5 days on either Krumeich's ring or polypropylene (PP) discs coated with individual components of the Krumeich's ring alloy followed by double vital staining with fluorescein diacetate (FDA) and propidium iodide (PI). RESULTS: The MTT assays revealed that higher doses of the extracts appeared to reduce the viability of HMVEC, while highly diluted extracts of molybdenum (Mo) powder appeared to increase the metabolic activity of HMVEC. The FDA-PI staining showed only a few live HMVEC on either cobalt (Co) or Mo-coated PP discs, compared to the respective titanium (Ti) and chromium (Cr) counterparts. Viable HMVEC appeared to attach to Krumeich's ring after a 5‑day incubation period. CONCLUSION: The results confirm that Krumeich's ring does not exert measurable cytotoxic effects in our chosen assay system. High dilutions of medium-soluble Mo powder extracts appear to increase the metabolic activity of HMVEC.
Authors: Christian Schmidt; Fabiano Yokaichiya; Nurdan Doğangüzel; Margareth K K Dias Franco; Leide P Cavalcanti; Mark A Brown; Melissa I Alkschbirs; Daniele R de Araujo; Mont Kumpugdee-Vollrath; Joachim Storsberg Journal: Biomedicines Date: 2016-09-15