A new storage medium containing amphotericin B versus Optisol-GS for preservation of human donor corneas.

BACKGROUND/AIM: We compared the quality of human donor corneas stored in a cold storage medium containing 2.5 µg/ml of amphotericin B (Kerasave, AL.CHI.MI.A. S.R.L., Ponte San Nicolò, Italy) and Optisol-GS (Bausch & Lomb Inc., Bridgewater, NJ, USA) for 14 days. METHODS: Sixteen pairs of human donor corneas were collected in Eusol-C (AL.CHI.MI.A. S.R.L., Ponte San Nicolò, Italy). Next, all tissues underwent the first evaluation that included the assessments of central corneal thickness (CCT), endothelial cell density (ECD) measured using both trypan blue staining and specular microscopy, endothelial cell (EC) mortality and morphology, and corneal transparency within 24 hours from recovery (Day 1). Afterwards, one cornea of each pair was transferred into Kerasave or Optisol-GS. ECD and CCT were also assessed at Day 7, and all the metrics were evaluated again at the end of the storage period (Day 14). RESULTS: At all tested time points, no differences were found in the qualitative (corneal transparency, EC morphology) and quantitative metrics (ECD, CCT, EC mortality) between the Kerasave and the Optisol-GS storage groups. At Day 14, the corneas stored in Kerasave and Optisol-GS showed ECD of 2312±98 and 2335±128 cells/mm2 (p=0.886), CCT of 717±17 and 697±19 µm (p=0.454) and central EC mortality of 0.54%±0.40% and 0.14%±0.14% (p=0.719), respectively. CONCLUSIONS: The new amphotericin B-containing medium Kerasave was comparable to Optisol-GS in terms of preservation of corneal characteristics at 2-8°C for 14 days.

A new approach to extend the storage of donor corneas after 28 days of corneal culture in an Italian eye bank.

This study aimed to evaluate the possibility to extend the storage of unused organ-cultured donor corneas. After 28 days of corneal culture in TISSUE-C (AL.CHI.MI.A. S.R.L., Italy) and 5-day storage in transport/deswelling medium CARRY-C (AL.CHI.MI.A. S.R.L., Italy), 25 corneas that were deemed suitable for transplantation were transferred in fresh TISSUE-C at 31 °C for additional 7 days and then in fresh CARRY-C at room temperature for 24 h. Tissues were assessed for endothelial cell density (ECD), endothelial mortality and morphology after the standard and the extended corneal storage. In addition, the effect of donor age < 85 years and ≥ 85 years on corneal characteristics was assessed. After the extended storage, 6 out of 25 tested corneas (24%) showed ECD values below the acceptance limit (< 2000 cells/mm2). 19 corneas (76%) were still suitable for transplantation and showed a 5.9% loss in ECD, which was not statistically significant (P = 0.0949) compared to standard storage period. The two donor age groups did not show statistically significant differences in any tested parameter, although a trend for lower ECD and higher mortality in Descemet's folds after standard storage was observed in the ≥ 85 age donor group. Thus, the attempt of the current study to provide new sight-restorative options for unused tissues and increasing the availability of corneas in case of shortage gave encouraging results. Although a higher vulnerability of corneas from very old donors could not be statistically demonstrated in the present study, higher sample size could be required for prolonging the shelf life of these tissues.

Method for sterility testing of corneal storage and transport media after removal of interfering antimicrobials: prospective validation study in compliance with the European Pharmacopoeia.

OBJECTIVE: This study aimed at validating the method for sterility testing of the corneal culture medium, TISSUE-C, and the transport/deswelling medium, CARRY-C, according to the method suitability test, as defined by the European Pharmacopoeia (EP), using RESEP, which is a new medical device for removal of antimicrobial agents and an automated culture system. METHODS AND ANALYSIS: The six EP reference strains were inoculated in TISSUE-C and CARRY-C. Half of the samples were treated with RESEP (RESEP+ group) prior to the sterility testing, whereas the remaining samples were untreated (RESEP- group). Growth controls were obtained by direct inoculation of the micro-organisms in the culture broths. Microbial growth was read by an automated light scattering culture system within 48 hours. RESULTS: The use of RESEP allowed detection of microbial growth in 100% of the tested samples, with a mean time to detection (TTD) comparable with that of the growth control group. Significantly lower sensitivity (38.83%±20.03% for both media, P<0.05) and TTD variability, depending on the tested micro-organism, were observed in the RESEP- group. The method specificity was 100% for both groups. CONCLUSION: The use of RESEP increased the sensitivity of the sterility testing method to 100% and, for the first time, allowed validation of the method for sterility testing of corneal storage media according to the EP method suitability test. This further increases the safety of the corneas intended for transplantation.

Genetic control of chemokines in severe human internal carotid artery stenosis.

BACKGROUND AND PURPOSE: Atherosclerosis is an inflammatory disease. Chemokines and chemokine receptors are known to be involved in atherogenesis. Common single nucleotide polymorphisms (SNPs) affect transcription in response to inflammatory stimuli. The aim of this study was to evaluate the correlations between MCP-1, RANTES, SDF-1, CCR2, and CCR5 gene polymorphisms with increased risk of internal carotid artery (ICA) stenosis. METHODS: Hundred and twelve patients, consecutively recruited for ICA occlusive disease, and 282 controls were genotyped for MCP-1-2518G, RANTES-403A, CCR5Delta32, CCR2 V64I, and SDF-1-801A polymorphisms. RESULTS: The frequency of the SDF-1A allele was significantly different between cases and controls: 0.32 vs. 0.20, respectively (OR 1.81; 95% CI 1.25-2.60; p=0.007). The frequency of the RANTES-403G allele was significantly higher in patients with stenosis >70% (OR, 2.45; 95% CI 1.12-5.71; p=0.015). No significant differences were observed with the other polymorphisms. CONCLUSION: The reported results seem to correlate the polymorphisms of the genes encoding for SDF-1, RANTES with pathogenesis and progression of ICA occlusive disease. Although suggestive, these results need confirmation in prospective cross-sectional studies.