P20-A129†An innovative wound healing method reveals a donor and post-mortem time-dependent regeneration of corneal epithelium.

PURPOSE: The aim of this study was to establish and optimize a new and reproducible epithelial wound healing model on human corneas. This assay was used to study the kinetics of epithelial regeneration following a chemical injury. METHODS: Thirty (n=30) human corneas unsuitable for transplant were used for the experiments. Corneas were cultured in Storagix medium (FBOV) at 31°C. Epithelial integrity before the beginning of the experiments (pre-wound) was assessed using the vital dyes trypan blue (TB, TB-S 0.25%, AL.CHI.MI.A. srl) and sodium fluorescein (Fluo). 1-heptanol soaked paper disks (6 mm) were applied in the centre of the corneas for 1' to trigger a chemical damage at the epithelial layer. Afterwards, sodium fluorescein and TB stainings were repeated to quantify the damaged area and to monitor healing progression. The damaged area (mm2) was calculated for each time point with Fiji software. Wound healing rate (HR, mm2/die) was calculated for both Fluo (HRF) and TB (HRTB) measurements using the previously described formula:Arithmetical averages (HRFAVG and HRTBAVG) of HRs were calculated and correlated by Pearson correlation coefficient with the following donor's parameters: age, sex, post-mortem time (PMT, time between death and tissue procurement), stromal defects, septicaemia, body temperature, diabetes. RESULTS: The execution of the heptanol wounding is highly reproducible, as highlighted by Fluo and TB staining. The average time for full recovery from wounding was 3,8 ± 0,41 days for Fluo and 3,5 ± 0,63 days for TB. Fluo and TB stainings are interchangeable as they significantly correlate (Pearson correlation coefficient = 0.630; p>0.05). A negative linear correlation was observed between HR and PMT (HRFAVG: corrected R2: 0.243, p = 0.003; HRTBAVG: corrected R2: 0,132, p = 0.028), but not with the other donors' parameters. CONCLUSION: Our wound/healing model might be of great interest for studies of epithelial regeneration kinetics and validation of drugs for the treatment of ocular defects. The inverse correlation between PMT and HR provides valuable insights for scientists investigating the regenerative properties of the corneal epithelium, as well as for eye bank personnel aiming to preserve the regenerative potential of corneal epithelium.

P26-A125†Donation medicine: a change of paradigm in procuring ocular tissues for transplantation.

PURPOSE: To reflect on the implementation of the concept of 'Donation Medicine' as a substitute for 'Procurement' to describe the Foundation's activities in the procurement of ocular tissue and donor selection, considering that the prevailing connotation of procurement (the action of obtaining materials, goods and services necessary to the functioning of a productive activity) did not express satisfactorily all the social, human and medical implications of a programme aimed at promoting ocular tissue donation and recovery. Moreover, in medicine the term 'Procurement' is generally associated with the worst therapeutic outcome, which is the end of a human life. METHODS: A retrospective evaluation of the main indicators pertaining to activities in 2021 was performed, with particular regard to donor screening ,tissue recovery, and the human and professional relations with donor families and hospital staff. The results were assessed by an interdisciplinary team, composed of eye bank and healthcare personnel, regulators and experts in medical humanities. RESULTS: In 2021, in light of 2944 non-oppositions to donation (opting out system), 891 consultations of the national SIT donor registry were performed (Sistema Informativo Trapianti), with 2551 clinical charts reviewed, 4332 related phone consultations performed, and 2032 nasopharyngeal swabs for SARS-CoV-2 nucleic acid tested; as a consequence, 2213 condolence and gratitude letters were sent to donor families, of which 57%(1269) conveyed the outcome of donation, along with 115 gratitude letters sent in instances of the non-recovery. 24 families requested, and were granted, the opportunity to visit the eye bank. CONCLUSION: A consensus was reached on the evidence that the term 'Procurement' has obvious limitations in the long term nurturing and maintenance of the motivation of the eye bank and healthcare personnel. As a consequence, the concept of 'Donation Medicine' was implemented to define and develop the activities related to the promotion of donation, the recovery of ocular tissues for transplantation, and internal/external relations with healthcare personnel, thus changing the meaning of 'Procurement', from a process at the end of a life to the realization of a new pathway of care that takes into account both donor families and recipients. Donation medicine begins with the re-opening of the donor clinical chart, the interaction with donor relatives and the recovery of a precious gift for use in the restoration of sight of patients.

Presence of SARS-CoV-2 RNA in human corneal tissues donated in Italy during the COVID-19 pandemic.

OBJECTIVE: To analyse corneal tissues from asymptomatic donors with a postmortem nasopharyngeal swab tested positive for the presence of SARS-CoV-2 RNA, and therefore, understand the role that corneal transplantation may have in viral transmission. METHODS AND ANALYSIS: Between March 2020 and October 2021, 101 corneas (out of 8154 collected in Italy) from 51 donors (out of a total of 4155 Italian donors) positive for SARS-CoV-2 after postmortem nasopharyngeal swab tests were analysed for the presence of SARS-CoV-2 RNA through real-time RT-PCR. When available, the corneal tissue storage media were also assessed. Corneas and/or storage media with confirmed presence of SARS-CoV-2 RNA were further investigated by isolating SARS-CoV-2 virions, which were used to infect VeroE6 target cells. RESULTS: Only N=4 corneas and/or storage media out of 101 showed presence of SARS-CoV-2 RNA. No VeroE6 cell infection was detected with viral isolates, thus suggesting no presence of SARS-CoV-2 virions in corneal specimens and storage media. CONCLUSIONS: The presence of SARS-CoV-2 in cornea specimens would seem to be more likely due to prolonged detection of RNA rather than to active viral replication, with very low risk of infectivity and transmission through keratoplasty.

5†The impact of the pandemic on ocular tissue procurement : the experience of fondazione banca degli Occhi del veneto.

INTRODUCTION: Since 21 February 2020, the day that the first Italian COVID-19 case was identified, the organizational and regulatory conditions for ocular tissue donation have undergone numerous changes in order to guarantee safety and quality. Herewith we report the key responses of the procurement programme to these challenges. MATERIALS AND METHODS: A retrospective analysis of the ocular tissue procured between 1 January 2020 and 30 September 2021 is reported. RESULTS: 9224 ocular tissues were procured during the study period (weekly average: 100 ± 21 tissues, mean ± SD; down to 97 ± 24, if only 2020 is considered). During the first wave, the weekly average reached 80 ± 24 tissues, a significant reduction if compared to the first 8 weeks of the year (124 ± 22 tissues/week, p<0.001), falling to 67 ± 15 tissues/week during the lock-down period. Considering the ocular tissues collected in the Veneto Region alone, the weekly mean was 68 ± 20, a reduction when compared to the first 8 weeks of the year (102 ± 23, p<0.001), arriving at 58 ± 15 tissues/week during the lock-down period. The percentage of healthcare professionals who tested positive during the first wave was on average 12% of the positive cases in the whole country, and equal to 18% in the Veneto Region alone. During the second wave, the mean weekly recovery of ocular tissue was 91 ± 15 and 77 ± 15 in the Veneto Region, compared to positive cases of healthcare professionals of 4% across Italy and in the Veneto Region. During the third wave, the overall weekly mean recovery rate was 107 ± 14, and 87 ± 13 in the Veneto Region, with only 1% of positive cases among healthcare professionals in Italy and in the Veneto Region. CONCLUSIONS: The most dramatic decrease of ocular tissue recovery occurred during the first wave of COVID-19, notwithstanding the lower number of infected people. This phenomenon can be attributed to different factors: a high percentage of positive cases and/or contacts among potential donors; the number of infections among healthcare professionals, favoured by the lack of personal protection equipement and the still partial knowledge of the disease; the exclusion of donors with bilateral pneumonia. Subsequently, the system was better organized with the assimilation of new knowledge about the virus, overcoming the initial fears about transmission and thus guaranteeing the resumption and maintenance of donations.