Postersitzungen, Freitag, 2.10.2015

 
Foyer Estrel 13:15 - 14:15 02.10.2015
Postersitzung PFr02
Kornea / Konjunktiva / Grundlagen Cornea / Conjunctiva / Basics
Vorsitzende/r: Tina Dietrich-Ntoukas (Berlin), Peter Rieck (Berlin)

Referent/in: Natalia Sheptukha (Dnipropetrovsk)
Introduction: Corneal injuries invoke serious structural and functional defects of the eye due to subsequent inflammatory processes and increased oxidative stress in its tissues. Objectives: To determine the most effective combination among NSAIDs and antioxidants for treatment of traumatic injury to the cornea, having evaluated the effectiveness of the agents as follows: 0,1% Diclofenac +1% Thiotriazolin (comb #1); 0,1% Diclofenac+1% Methylethylpiridinol(comb#2); 0,1% Diclofenac + 1% Taufon (comb#3); 0,1% Indometacin+1% Thiotriazolin (comb#4); 0,1% Indometacin + 1% Methylethylpiridinol (comb#5); 0,1% Indometacin + 1% Taufon(comb#6) Aims: Improving compliance in treatment of corneal injury by means of combined drugs. Methods: 35 chinchilla rabbits of both sexes were placed into 7 groups 5 animals each. Under local anesthesia with a 0.5% solution of Propacaine hydrochloride, a 6x6 mm mark by trephine was applied to the centre of the right cornea, followed by staining with 1% Fluoresceine. A corneal epithelial abrasion was then created within the stained tissues of each of the 35 rabbits. The animals in the first six groups then received instillations of the aforementioned combinations of agents (one combination per group QID in the right eye). The seventh group (control) received instillations of phosphate buffered saline QID in the right eye. The sizes of the lesions were later determined by staining with 1% fluorescein under a slit lamp on day 0, 1, 2, 3, 4. Results: Treatment with comb#1 resulted in reduction of the lesion area by 1.8 times at 24 h. Treatment with comb # 4 resulted in a 1.6x decrease, while comb # 2, 3, 5, 6 resulted in a < 1.4x decrease. Complete lesion resolution was observed at 48 h following treatment with comb # 1; complete damage epithelialization was observed after 72 h of treatment in the other five groups, using their respective combinations. Complete epithelialization was observed only in 3 animals within the control group. The lesion resolution rate and corneal thickness in the group treated with comb # 1 was greater than in the other five groups. Treatment with comb # 1 also exhibited better epithelial and stromal organization unlike other combinations. Conclusion: The combination of 0.1% diclofenac + 1% thiotriazoline has the highest anti-inflammatory and healing effects and can be used to treat corneal lesions of noninfectious etiology.
Referent/in: Gábor Tóth (Budapest)
Purpose: To analyze the impact of corneal crosslinking on corneal lymphatic vessels. Methods: The mouse model of suture-induced corneal neovascularization was used to assess the effect of corneal crosslinking with riboflavin on mature lymphatic vessels. The treatment group underwent corneal abrasion followed by 0,1% riboflavin solution (Mediocross H, Peschke, Germany) application for 30 minutes and UVA light (365 nm, 3 mW/cm2) illumination for 30 minutes. Fifteen untreated eyes served as controls. Five corneas of each group were excised at days 1, 4 and 8 after crosslinking. The presence of lymphatic vessels was determined using Lyve-1 staining and analyzed morphometrically by using a method based on the program Cell˄F. Results: After days 1 and 8, lymphatic vessels showed no significant (p=0,4172 and p=0,6396) reduction following corneal crosslinking. Four days after treatment, the amount of lymphatic vessels was reduced significantly (p=0,0106). Conclusions: Corneal crosslinking may induce regression of mature lymphatic vessels in the cornea and may be a promising treatment option to regress preexisting corneal lymphatic vessels prior to keratoplasty. Support: EU COST BM1302; DFG FOR 2240
Referent/in: Tanja Stachon (Homburg/Saar)
Einleitung: Die Ursachen eines Keratokonus sind bisher nicht vollständig geklärt. Eine mögliche Ursache für den Verlauf der Krankheit könnten metabolische Veränderungen sein, die sich nachteilig auf die biomechanische Stabilität der Kornea auswirken könnten. Ziel dieser Studie ist es, die Konzentrationen von Harnstoff, Harnsäure, Prolaktin und fT4 in Kammerwasserproben von Keratokonus-Patienten (KC) mit Kontrollpatienten zu vergleichen. Methode: Die Kammerwasserproben wurden bei 100 Patienten (Alter 41,9 ± 14,8 Jahre) mit diagnostiziertem Keratokonus (69 Männer) im Rahmen einer geplanten perforierenden Keratoplastik, und bei 100 Patienten (Alter 71,2 ± 12,3 Jahre) bei geplanter Katarakt Operation als Kontrollproben (58 Männer) entnommen. Die Messung der Harnstoff- und Harnsäurekonzentrationen aus dem Kammerwasser (KW) erfolgte mit dem Analysegerät ADVIA 1800, Prolaktin und fT4 wurden mit dem ADVIA Centaur der Firma Siemens erfasst. Die Ethikkommissionen der Bundesländer Saarland und Rheinland-Pfalz haben dieser Studie zugestimmt. Die statistische Auswertung erfolgte mit einem generalisierten linearen Modell (GLM). Ergebnisse: Die Harnstoffkonzentrationen im KW zeigten bei KC-Patienten Werte von 11,88 mg/dl und in der Kontrollgruppe von 16,44 mg/dl. Die Harnsäurewerte lagen bei 2,04 mg/dl vs 2,18 mg/dl, Prolaktin bei 3,18 ng/ml vs. 3,33 ng/ml, und fT4 bei 20,57 pmol/l vs. 19,06 pmol/l. Die Harnstoffkonzentrationen im KW sind von der Diagnose (p=0,025), Geschlecht (p =0,39) und Alter (p=0,001) abhängig. Die Harnsäurekonzentration zeigt mit keinem dieser Parameter einen Zusammenhang (p>0,056). Die Prolaktin und fT4 Konzentrationen hängen von der Diagnose der Patienten (p=0,009, p=0,006) ab, sind aber von Geschlecht und Alter unabhängig (p>0,18). Zusammenfassung: Harnstoff und Prolaktin Konzentrationen sind im Kammerwasser von Keratokonus Patienten erniedrigt und fT4 Konzentrationen erhöht. Die Harnstoffkonzentration im Kammerwasser hängt außer der Diagnose mit dem Alter und Geschlecht zusammen. So sind die Harnstoffkonzentrationen bei Keratokonus-Patienten erniedrigt, bei älteren Patienten und Männern erhöht.
Referent/in: Tanja Stachon (Homburg/Saar)
Einleitung: Eine mögliche Ursache eines Keratokonus (KC) könnten metabolische Veränderungen sein, die sich auf die biomechanische Stabilität der Kornea auswirken. Harnstoff (HS) wird im Zytosol als Abfallprodukt gebildet, und ist an der Carbamylierung von Kollagen I beteiligt, was einen positiven Einfluss auf die Widerstandsfähigkeit der Kollagenfasern gegenüber den Matrix-Metalloproteinasen hat. Hydroxyprolin stabilisiert im Kollagenmolekül den Zusammenhalt der Kollagen-Tripelhelix. Ziel dieser Studie ist es, die Basiskonzentration von HS, sowie den Effekt von HS auf die Viabilität, Proliferation, Kollagensekretion (KS)- und Hydroxyprolinanteil des Kollagens (HP) von primären KC- und normalen Keratozyten in vitro zu untersuchen. Methode: Primäre humane Keratozyten wurden durch enzymatische Behandlung mit Collagenase A aus humanen Korneoskleralscheiben (n=5) und von Explantaten von geplanten perforierenden Keratoplastiken (KC Patienten) isoliert (n=6) und in DMEM/Ham´s Kulturmedium, versetzt mit 10% fetalem Kälberserum kultiviert. Für den Testansatz wurden die Zellen mit HS-Konzentrationen von 0,5, 1,0, 5,0 und 10 mM für 24 h inkubiert. Die Viabilität, Proliferation und HS-Konzentration der Keratozyten wurden photometrisch, die KS und HP aus dem Kulturüberstand mit einem Enzyme linked immuno absorbent assay (ELISA) analysiert. Ergebnisse: Die Basiskonzentrationen von HS, KS und HP waren in KC-Keratozytenkulturen signifikant niedriger als in normalen Keratozytenkulruren (p< 0,008). Die Zugabe von HS hat keinen Einfluss auf die Sekretion von Kollagen, den Hydroxyprolinanteil und die Viabilität der KC- oder normalen Keratozyten (p>0,09), führte jedoch zu einer erhöhten Proliferation von KC-Keratozyten im Vergleich zur unbehandelten KC Kontrolle (p=0,04 für alle Konzentrationen). Die Proliferation normaler Keratozyten blieb trotz Zugabe unterschiedlicher HS Konzentrationen im Vergleich zur unbehandelten Kontrolle unverändert (p>0,84). Zusammenfassung: Harnstoffkonzentration-, Kollagensekretion- und Hydroxyprolinanteil des Kollagens ist bei KC-Keratozyten erniedrigt. Eine vermehrte Gabe von Harnstoff zeigt keinen Effekt auf die Viabilität, Kollagensekretion und Hydroxyprolinanteil bei normalen und KC-Keratozyten, jedoch einen proliferationsfördernden Effekt auf KC-Keratocyten.
Referent/in: Tatyana Zhmud (Vinnitsa)
Aim: To study the level of methylglyoxal and lactat in the cornea of rabbit at streptozotocin-induced diabetes. Material and methods: Experimental studies were performed in rabbits in which reproduced streptozotocin model of diabetes. Diabetes was induced by intravenous injection of streptozotocin (55 mg per 1 kg of animal body weight) dissolved in 10 mM citrate buffer, pH 4.5. Control animals are injected solvent (10 mM citrate buffer). In the rabbit cornea methylglyoxal and lactate levels were determined spectrophotometrically using the method of enzymatic analysis. Results: As a result of under taken biochemical studies the considerable increase of level of ketonic connections was educedin the tissue of cornea, as compared to a norm their concentration for animals with streptozotocin-induced diabetes increased morethanin 2 times. In the same terms maintenance of lactatin a cornea rose on the averageon 65%, making (6,3±0,25) the mM/g of moist weight, at the norm (3,8±0,17) of mM/g of moist weight. Conclusion: Analyzing the data, reflecting the level of oxo and hydroxy compounds in the cornea of rabbits with streptozotocin diabetes can conclude that in the corneal tissues of diabetic animals significantly increased the rate of oxidative glycation of protein structures. This factor can be considered as the most important pathogenetic link diabetic keratopathy.
Referent/in: Anja Grünert (Erlangen)
Fragestellung: Rekombinante adenoassoziierte Viren 2 (rAAV2) stellen aufgrund ihrer Nonpathogenität eine vielversprechende und sichere Methode zur Gentherapie des cornealen Endothels dar. Da die Transgenexpression der einzelsträngigen (ss) DNS-Vektoren von der Synthese des komplementären DNS-Stranges abhängig ist, zeigt sich, vor allem in der frühen Phase nach der Transduktion, meist nur eine geringe bis moderate Genexpression. Dieses Problem kann mithilfe von selbstkomplementären (sc) AAV2-Vektoren, die 2 komplementäre DNS-Sequenzen in einem Kapsid enthalten, umgangen werden. In dieser Studie vergleichen wir die Transduktionseffizienz von ss- und sc-AAV2 in humanen cornealen Endothelzellen. Methodik: Eine humane corneale Endothelzellinie (HCEC-12) sowie organkultivierte, humane Spenderhornhäute wurden für jeweils 48 Stunden mit ss- oder sc-AAV2 Vektoren in verschiedenen Konzentrationen inkubiert. Zur Evaluation der Transduktionseffizienz enthielten die Vektoren grün fluoreszierendes Protein (GFP) als Transgen. Die GFP-Expressionskinetik in HCEC-12 Zellen wurde über einen Zeitraum von 4 Wochen mithilfe der Durchflusszytometrie untersucht. Die Transgenexpression in humanen Spenderhäuten wurde mithilfe der konfokalen Mikroskopie ausgewertet. Ergebnisse: 2 Tage nach der Transduktion exprimierten bis zu 75,3% der mit sc-AAV2 transduzierten Zellen und bis zu 67,3% der mit ss-AAV2 transduzierten Zellen das GFP-Transgen. Je niedriger der verwendete Vektortiter war, desto größer war jeweils der Unterschied in der Transduktionseffizienz. Bei Verwendung von niedrigen Vektortitern erzielte der sc-Vektor eine bis zu dreifach höhere GFP-Expressionsrate im Vergleich zum ss-Vektor. Für beide Vektoren zeigte sich zunächst ein Anstieg der GFP-Expression bis zum Tag 5 mit anschließender Abnahme. Die Transduktion mit sc-AAV resultierte in einer deutlich verlängerten Genexpression (35,3% GFP-positive Zellen (sc-AAV) versus 12,1% GFP-positive Zellen (ss-AAV) an Tag 12). Schlussfolgerungen: Die Verwendung von sc-AAV2-Vektoren kann die Transduktionseffizienz in humanen cornealen Endothelzellen verbessern. Dies könnte vor allem für die Gentherapie zum Schutz von organkultivierten Spenderhornhäuten vor der Transplantation von Nutzen sein.
Referent/in: Aytan Musayeva (Mainz)
Catecholamines were reported to mediate trophic effects in the corneal epithelium. The major goal of the present study was to test the hypothesis that the lack of a single α1-adrenoceptor (α1-AR) subtype affects corneal epithelial thickness and cell proliferation in mice. Expression of mRNA was quantified for individual α1-AR subtypes in whole corneal explants of mice deficient in one of the three α1-AR subtypes (α1A-AR-/-, α1B-AR-/-, α1D-AR-/-, respectively) and wild-type controls by real-time PCR. Moreover, mRNA expression for individual α1-AR subtypes was determined in the corneal epithelium, stroma, and endothelium from wild-type mice. The central corneal epithelial thickness was assessed from cryosections of all four mouse genotypes. Furthermore, cell proliferation rate in the corneal epithelium was calculated in corneal cryosections stained with a Ki67-specific antibody using fluorescence microscopy. Also, the amount of cell layers and the mean epithelial cell size were determined in stained cryosections. Using real-time PCR, mRNA for all three α1-AR subtypes was detected in the cornea with a rank order of abundance of α1A ≥ α1B >> α1D. The lack of a single α1-AR gene did not affect the mRNA expression levels of the remaining two receptor subtypes. In the corneal epithelial layer from wild-type mice, the mRNA expression pattern was similar to that of the whole cornea. In contrast, in the stroma no α1-AR mRNA was detected while in the endothelium only mRNA coding for the α1B-AR was found. Central corneal epithelial tickness was reduced by about 20% in α1A-AR-/- compared to wild-type mice. Proliferation rate and the amount of cell layers did not differ between individual mouse genotypes. In contrast, the mean epithelial cell size was markedly reduced in α1A-AR-/- mice. In conclusion, the study suggests that the α1A-AR subtype mediates trophic effects in the mouse corneal epithelium under physiological conditions. Selective ligands for the α1A-AR subtype may become useful to understand corneal epithelial cell physiology and to modulate regeneration of the corneal epithelium.
Referent/in: Oleksandra Zborovska (Odesa)
Purpose: To increase the effectiveness of fungal inflammatory eye diseases treatment by using in addition to standard therapy the photodynamic therapy (PDT) with methylene blue (MB) and laser radiation. Setting: The Filatov Institute of Eye Diseases and Tissue Therapy, NAMS Ukraine, Ukraine, Odessa. Methods: We established suitable laser radiation parameters. We compared antifungal effect of different MB concentrations (0.05%, 0.1%, 0.2%) on Candida albicans “in vitro” by optical density. We modeled fungal keratitis in 15 Chinchilla rabbits. All rabbits were divided into two groups. Rabbits of the main group received standard anti-inflammatory therapy and PDT. Rabbits of the control group received only standard anti-inflammatory therapy,. Patients with severe fungal keratitis (44 people, 44 eyes) received standard therapy. 22 of them in addition to this treatment also received PDT with methylene blue. In all patients corneal infiltrate area and erosion area exceeded 50%. The observation period was 3 months. Outcome measures were reduction of infiltration area, absence of fungal contamination. Results: During “in vitro” experiment we established suitable parameters for PDT. We determined MB concentration as 0.1% and laser exposure as 3 min. Rabbits: in the control group with moderate fungal keratitis duration of a disease was 14,25±1,0 days (outcome local stromal opacity with neovascularisation), and 21,1 ± 1,7 days with severe keratitis (outcome – intensive stromal opacity with active neovascularisation). In the main group with moderate fungal keratitis duration of a disease was 7,15 ± 0,75 days (outcome – dotted superficial opacity), and severe - 14,25 ± 1,0 days (outcome – local stromal opacity with inactive neovascularisation). On the 14th day from the begining of treatment patients with corneal infiltrate and erosion area less than 50% apperared in both groups. C. albicans didn’t identified in inflammatory focus in main group in a month. After 3 months: proportion of patients with infiltrate area less than 50% was 72.2% in main group, while in control group only 35,3%; proportion of patients with erosion area less than 50% was 89,6% in main group, while in control group only 53,1%. Conclusions: PDT effectiveness is confirmed by experimental and clinical studies. PDT with 0.1% MB is an effective treatment of fungal (C. albicans) keratitis. PDT requires further studies in treatment of fungal inflammatory eye diseases.
Referent/in: Kateryna Sereda (Odessa)
Introduction: Efficiency of amniotic membrane transplantation (AMT) in bacterial keratitis treatment remains the least studied. Human AM thanks to its antibacterial, anti-angiogenic, anti-inflammatory and anti-fibroblastic properties took significant place in reconstructive surgery of the eye surface. Thanks to these properties human AM may play an important role in the treatment of infectious keratitis. Aim: To study anti-inflammatory action of viable cryopreserved amniotic membrane (AM) using different surgical techniques of its fixation on the bacterial keratitis model. Methods: Human AM was cryopreserved with 5% DMSO by slow conventional freezing protocol with automatic controlled seeding. In the experiment on bacterial keratitis model AM transplantation was performed using the techniques of biological covering (BC) in 30 rabbits and graft transplantation (GT) in 30 rabbits. This technology provides safety of AM cell activity after thawing and reduces AM properties loss. In BC group AM episcleral fixation was used, covering the entire corneal surface. In GT group AM was secured by sutures to the corneal defect edge only. Animal eyelids were sutured during 1 month follow up period. Results: In the BC group AM was intact on the surface of the cornea in 24 rabbits. In 18 rabbits mild edema in the corneal stroma was observed. Corneal epithelization was completed in all the cases and no vascularization marked. In the GT group AM was intact on the surface of the cornea in 18 rabbits. In 18 rabbits mild and in 6 rabbits diffuse edema was observed. In 12 cases the development of vascularization and in 6 cases corneal infiltration were found. Significance of inflammation signs difference in the group with BC and GT ranged from 0.048 to 0.0001. Conclusions: Graft transplantation group showed more severe inflammatory response if compared with biological covering group. At the same depth of the corneal destruction by bacterial infectious process biological covering technique should be prefered as less traumatic surgical intervention, which is accompanied by a lower inflammatory response.
Referent/in: Yevgeniya Ilyina (Kharkov)
Background: Restoration of the corneal superficial epithelium after it damaging occurs for the division and migration of the basal epitheliocytes, and also transformation and centripetal movement of the limbal stem cells. At their insufficiency there is a pathological condition named the limbal stem cell deficiency. Objectives: To study features of formation of superficial corneal epithelium at the limbal stem cell defficiency after the autograft transplantation. Materials and methods.The experimental research has been executed on 28 rabbits. It has been simulated the partial limbal stem cell defficiency. Limbal biopsy was performed on normal contralateral eyes and grown on 3T3 fibroblasts. 14 rabbits received the autograft in the space formed between the limbal tissue and corneal tissue and 14 rabbits receive the drug treatment of the limbal stem cell defficiency. Results: In experimental group on 3,8±0,4 days it was marked partial epithalization of the corneal defect. Full epithalization has occur on 14,1±0,9 days, p < 0,001. In 7 days control group ,corneal defect was absent and the surface was rough.Partial epitalization was noted on 6,7±0,2 days, p < 0,01. Full epitalization has occurred on 14,1±0,9 days, p < 0,001. In experimental group the neovascularization were absent in all 14 eyes. The cornea was transparent in all 14 eyes. In the control group for 7 days the turbidity was 0,9±1,1 points, the neovascularization was 1,6±0,7 points, for 14 days turbidity was 1,4±0,9 points, the neovascularization was 2,4±0,5 points. Morphologically for 7 day after the limbokeratofilling forward corneal epithelium of a non-uniform thickness – from 3-4 till 11-12 numbers in proliferative zones. Overlying cells some the smaller sizes, remain the roundish form of kernels, only in superficial 1-2 numbers of cells. For 14 days, microscopical research of a cross-section cut from the cornea completely epithelization, was covered by 4-5 numbers of cells with an accurate differentiation on the layers.In control group for 7 days after deepithalization morphologically infringement of differentiation corneal epithelium, with presence uncharacteristic for it cells. For 14 days it was marked the conjunctivalization, with the goblet cells and the new vessels. Conclusion: The operation with the fixation of the cultivated limbal epitheliocytes to rabbits with the stem cells defficiency on the surface between the cornea and sclera restored a high-grade corneal epithelium.
Referent/in: Ming-Feng Wu (Homburg/Saar)
Purpose: Autologous serum (AS) eye drops offer a potential treatment alternative for non-healing corneal epithelial defects in clinical practice. In corneal epithelial cell cultures, fetal bovine serum (FBS) is often used to support the growth of the cells. Our purpose was to analyse the concentration-dependent effects of AS and FBS on human corneal epithelial cells (HCEC) viability, migration and proliferation, in vitro. Methods: First, AS was prepared from 13 patients according to the regulations of the LIONS Cornea Bank Saar-Lor-Lux, Trier/Westpfalz. HCECs were firstly cultured in DMEM/F12 with 5% FBS, 0.5% DMSO, 10 ng/mL human epidermal growth factor, 1% insulin-transferrin-selenium, then were incubated in serum media which was consisting of DMEM/F12 supplemented by 5%, 10%, 15% or 30% AS or FBS. Thereafter, HCEC viability was analysed using Cell Proliferation Kit XTT, HCEC migration using wound healing assay, HCEC proliferation by the cell proliferation ELISA BrdU (colorimetric) kit. Statistical analysis was performed using Generalized Linear Model (GLZM), the values at 30% AS or 30% FBS were used as the baselines. Results: HCEC viability was the highest at 30% AS or 15% FBS and the lowest at 10% AS or 30% FBS application. HCEC migration was the quickest through 30% AS or 30% FBS and the slowest through 5% AS or 5% FBS concentrations. Proliferation was the most increased through 15% AS or 5% FBS and the least increased through 30% AS or 30% FBS concentrations. HCEC viability at 10% and 15% AS was significantly worse (P = 0.001, P = 0.023) compared to baseline and significantly better at 15% FBS (P = 0.003) concentrations. HCEC migration was significantly worse (P ≤ 0.007) and HCEC proliferation significantly better (P < 0.001) in all concentration groups compared to baseline. Conclusion: HCEC viability is mostly increased through 30% AS or 15% FBS, migration through 30% AS or 30% FBS and proliferation through 15% AS or 5% FBS. Therefore, we suggest the use of 30% AS in clinical practice.
Referent/in: Sven Schnichels (Tübingen)
Purpose: Last year we presented a novel class of DNA nanoparticles (NPs) and first experiments of neomycin and kanamycin conjugated DNA-NPs showed a prolonged adherence of the antibiotic (AB) to ex-vivo human and in-vivo rat corneas. Additionally, bacterial growth tests showed a retained activity of the ABs. This year, we present a quantitative evaluation of the amount of drug present on the eye and first toxicity studies. Methods: For drug delivery the kanamycin was conjugated to DNA-based NPs via aptamers. Ex-vivo pig eyes were exposed to NPs with ABs, then washed and transferred to petrifilms. Subsequently, 50 E.coli colonies were applied to the cornea and kept at 37°C for 48h. Afterwards the amount of bacteria on each cornea was determined. Furthermore, the residence time of the drug and NP were determined using an ocular fluorophotometer (Fluorotron™). Next, the amount of ABs present was evaluated by liquid chromatography–mass spectrometry (LC-MS). To exclude toxicity of the conjugated NPs, three ocular cell lines were incubated with the NP for 24 h and cell viability via MTS-assay, cell amount via crystal violet staining and apoptosis via caspase 3/7 assay was measured. Additionally, the same tests were performed using primary corneal epithelial cells. In order to further determine the toxicity profile, the AB conjugated NPs were dropped on rat eyes at different time-points and dosing regimes and screened for apoptotic cells. Results: For the bacterial growth we proved that after an incubation time and subsequent washing of 5 min the NP delivered kanamycin is significantly better than the pure AB. This effect lasts until 60 min of washing after which the NP delivered kanamycin also lost its function. Quantification using the fluorophotometer confirmed the longer presence on the cornea. The data from both experiments is consistent with the adhesion data obtained by fluorescence microscopy as pure kanamycin was not detectable after 5 min. Neither in-vitro cell toxicity screening nor the in-vivo experiments showed any toxicity. Conclusions: From the results obtained in the study it is obvious that the drastically improved adherence time of the AB-loaded NPs can directly be translated into antibacterial activity over prolonged times. However, evaluation of the delivery platform in an infected animal model is still necessary to fully explore the possibilities of this carrier system.