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Saini C, Chen TC, Young LH, Vavvas DG, Vangel M, Papaliodis GN, Mukai S, Turalba AV, Rhee DJ, Wu DM, Eliott D, Miller JB, Song BJ, Shen LQ, Pasquale LR, Chodosh J. Restoration of Vision in Severe, Cicatricial, Ocular Surface Disease with the Boston Keratoprosthesis Type II. Am J Ophthalmol 2022;Abstract
PURPOSE: To assess clinical outcomes of patients with severe, cicatricial ocular surface disease (OSD) implanted with the currently marketed design of the Boston keratoprosthesis type II (BK2). DESIGN: Retrospective cohort study. METHODS: Records of consecutive patients undergoing BK2 implantation from June 2009 to March 2021 were assessed for postoperative visual acuity, postoperative complications, device replacement, and additional surgeries. RESULTS: Fifty-six eyes of 53 patients with a mean follow-up of 45.8 months (range: 0.2-134.7 months) were included. Stevens-Johnson syndrome/toxic epidermal necrolysis was the most common indication (49.1%), followed by mucous membrane pemphigoid (39.6%) and other OSD (11.3%). Visual acuity improved from LogMAR 2.2±0.5 preoperatively to 1.5±1.2 at final follow-up. Fifty of 56 eyes saw ≥20/200 at some point postoperatively. Of the eyes with a follow-up of more than 5 years, 50.0% retained a visual acuity of ≥20/200 at their final follow-up. The most common complications, over the entire postoperative course (mean ∼4 years), were de-novo or worsening glaucoma (41.1%), choroidal effusions (30.3%), retinal detachment (25.0%) and end-stage glaucoma (25.0%). In a univariate analysis, patients who experienced irreversible loss of ≥20/200 visual acuity were more likely to have been previously implanted with an older design of BK2, less likely to be on preoperative systemic immunosuppressive therapy, and less likely to have undergone concurrent glaucoma tube implantation, compared to patients who retained ≥20/200 acuity (p<0.04 for all). CONCLUSIONS: Advances in device design and postoperative care have made implantation of BK2 a viable option for corneal blindness in the setting of severe cicatricial OSD.
Manley CE, Bennett CR, Merabet LB. Assessing Higher-Order Visual Processing in Cerebral Visual Impairment Using Naturalistic Virtual-Reality-Based Visual Search Tasks. Children (Basel) 2022;9(8)Abstract
Cerebral visual impairment (CVI) is a brain-based disorder associated with the maldevelopment of central visual pathways. Individuals with CVI often report difficulties with daily visual search tasks such as finding a favorite toy or familiar person in cluttered and crowded scenes. We developed two novel virtual reality (VR)-based visual search tasks combined with eye tracking to objectively assess higher order processing abilities in CVI. The first (virtual toybox) simulates a static object search, while the second (virtual hallway) represents a dynamic human search task. Participants were instructed to search for a preselected target while task demand was manipulated with respect to the presence of surrounding distractors. We found that CVI participants (when compared to age-matched controls) showed an overall impairment with visual search on both tasks and with respect to all gaze metrics. Furthermore, CVI participants showed a trend of worsening performance with increasing task demand. Finally, search performance was also impaired in CVI participants with normal/near normal visual acuity, suggesting that reduced stimulus visibility alone does not account for these observations. This novel approach may have important clinical utility in helping to assess environmental factors related to functional visual processing difficulties observed in CVI.
Dave TV, Nair AG, Joseph J, Freitag SK. Immunopathology of COVID-19 and its implications in the development of rhino-orbital-cerebral mucormycosis: a major review. Orbit 2022;:1-10.Abstract
PURPOSE: To present a literature review on various immunopathologic dysfunctions following COVID-19 infection and their potential implications in development of rhino-orbital-cerebral mucormycosis (ROCM). METHODS: A literature search was performed via Google Scholar and PubMed with subsequent review of the accompanying references. Analogies were drawn between the immune and physiologic deviations caused by COVID-19 and the tendency of the same to predispose to ROCM. RESULTS: Sixty-two articles were reviewed. SARS-CoV-2 virus infection leads to disruption of epithelial integrity in the respiratory passages, which may be a potential entry point for the ubiquitous Mucorales to become invasive. COVID-19 related GRP78 protein upregulation may aid in spore germination and hyphal invasion by Mucorales. COVID-19 causes interference in macrophage functioning by direct infection, a tendency for hyperglycemia, and creation of neutrophil extracellular traps. This affects innate immunity against Mucorales. Thrombocytopenia and reduction in the number of natural killer (NK) cells and infected dendritic cells is seen in COVID-19. This reduces the host immune response to pathogenic invasion by Mucorales. Cytokines released in COVID-19 cause mitochondrial dysfunction and accumulation of reactive oxygen species, which cause oxidative damage to the leucocytes. Hyperferritinemia also occurs in COVID-19 resulting in suppression of the hematopoietic proliferation of B- and T-lymphocytes. CONCLUSIONS: COVID-19 has a role in the occurrence of ROCM due to its effects at the entry point of the fungus in the respiratory mucosa, effects of the innate immune system, creation of an environment of iron overload, propagation of hyperglycemia, and effects on the adaptive immune system.
Alnahdi MA, Alkharashi M. Ocular manifestations of COVID-19 in the pediatric age group. Eur J Ophthalmol 2022;:11206721221116210.Abstract
The coronavirus disease 2019 (COVID-19) is now known to be associated with several ocular manifestations. The literature thoroughly discussed those that affect adults, with a lesser focus in the pediatric age group. We aim to outline the various pediatric ocular manifestations described in the literature. The manifestations may be divided into isolated events attributed to COVID-19 or occurring in the new multisystem inflammatory syndrome in children (MIS-C), a novel entity associated by COVID-19 infection. Ocular manifestations have virtually affected all ages. They manifested in neonates, infants, children, and adolescents. Episcleritis, conjunctivitis, optic neuritis, cranial nerve palsies, retinal vein occlusion, retinal vasculitis, retinal changes, orbital myositis, orbital cellulitis were reported in the literature with this emerging viral illness. Conjunctivitis was the most common ocular manifestation in MIS-C in nearly half of the patients. Other ocular manifestations in MIS-C were anterior uveitis, corneal epitheliopathy, optic neuritis, idiopathic intracranial hypertension, and retinitis. The clinical outcome was favorable, and children regain their visual ability with minimal or no deficits in most of the cases. Further follow-up may be warranted to better understand the long-term effects and visual prognosis.
Moussa O, Frank T, Valenzuela IA, Aliancy J, Gong D, De Rojas JO, Dagi Glass LR, Winn BJ, Cioffi GA, Chen RWS. Efficacy of Preoperative Risk Stratification on Resident Phacoemulsification Surgeries. Clin Ophthalmol 2022;16:2137-2144.Abstract
Purpose: To evaluate efficacy of a novel risk stratification system in minimizing resident surgical complications and to evaluate whether the system could be used to safely introduce cataract surgery to earlier levels of training. Materials and Methods: This is a retrospective cross-sectional study on 530 non-consecutive cataract cases performed by residents at Columbia University. Risk scores, preoperative best corrected visual acuity (BCVA), intraoperative complications, postoperative day 1 (POD1), and month 1 (POM1) exam findings were tabulated. The relationship between risk scores and POD1 and POM1 BCVA was modeled using linear regression. The relationship between risk scores and complication rates was modeled using logistic regression. Logistic regression was used to model the rates of complications across different levels of training. Rates of complications were compared between diabetic versus non-diabetic patients using t-tests. Results: Risk scores did not have significant association with intraoperative complications. Risk scores were predictive of corneal edema (OR = 1.36, p = 0.0032) and having any POM1 complication (OR = 1.20, p = 0.034). Risk scores were predictive of POD1 (β = 0.13, p < 0.0001) and POM1 (β = 0.057, p = 0.00048) visual acuity. There was no significant association between level of training and rates of intraoperative (p = 0.9) or postoperative complications (p = 0.06). Rates of intraoperative complication trended higher among diabetic patients but was not statistically significant (p = 0.2). Conclusion: Higher risk scores were predictive of prolonged corneal edema but not risk of intraoperative complications. Our risk stratification system allowed us to safely introduce earlier phacoemulsification surgery.
Jhaveri CD, Glassman AR, Ferris FL, Liu D, Maguire MG, Allen JB, Baker CW, Browning D, Cunningham MA, Friedman SM, Jampol LM, Marcus DM, Martin DF, Preston CM, Stockdale CR, Sun JK, Sun JK. Aflibercept Monotherapy or Bevacizumab First for Diabetic Macular Edema. N Engl J Med 2022;Abstract
BACKGROUND: In eyes with diabetic macular edema, the relative efficacy of administering aflibercept monotherapy as compared with bevacizumab first with a switch to aflibercept if the eye condition does not improve sufficiently (a form of step therapy) is unclear. METHODS: At 54 clinical sites, we randomly assigned eyes in adults who had diabetic macular edema involving the macular center and a visual-acuity letter score of 24 to 69 (on a scale from 0 to 100, with higher scores indicating better visual acuity; Snellen equivalent, 20/320 to 20/50) to receive either 2.0 mg of intravitreous aflibercept or 1.25 mg of intravitreous bevacizumab. The drug was administered at randomization and thereafter according to the prespecified retreatment protocol. Beginning at 12 weeks, eyes in the bevacizumab-first group were switched to aflibercept therapy if protocol-specified criteria were met. The primary outcome was the mean change in visual acuity over the 2-year trial period. Retinal central subfield thickness and visual acuity at 2 years and safety were also assessed. RESULTS: A total of 312 eyes (in 270 adults) underwent randomization; 158 eyes were assigned to receive aflibercept monotherapy and 154 to receive bevacizumab first. Over the 2-year period, 70% of the eyes in the bevacizumab-first group were switched to aflibercept therapy. The mean improvement in visual acuity was 15.0 letters in the aflibercept-monotherapy group and 14.0 letters in the bevacizumab-first group (adjusted difference, 0.8 letters; 95% confidence interval, -0.9 to 2.5; P = 0.37). At 2 years, the mean changes in visual acuity and retinal central subfield thickness were similar in the two groups. Serious adverse events (in 52% of the patients in the aflibercept-monotherapy group and in 36% of those in the bevacizumab-first group) and hospitalizations for adverse events (in 48% and 32%, respectively) were more common in the aflibercept-monotherapy group. CONCLUSIONS: In this trial of treatment of moderate vision loss due to diabetic macular edema involving the center of the macula, we found no evidence of a significant difference in visual outcomes over a 2-year period between aflibercept monotherapy and treatment with bevacizumab first with a switch to aflibercept in the case of suboptimal response. (Funded by the National Institutes of Health; Protocol AC ClinicalTrials.gov number, NCT03321513.).
VanderVeen DK, McClatchey TS, McClatchey SK, Nizam A, Lambert SR, Lambert SR. Effective lens position and pseudophakic refraction prediction error at 10½ years of age in the Infant Aphakia Treatment Study. J AAPOS 2022;Abstract
BACKGROUND: The refraction prediction error (PE) for infants with intraocular lens (IOL) implantation is large, possibly related to an effective lens position (ELP) that is different than in adult eyes. If these eyes still have nonadult ELPs as they age, this could result in persistently large PE. We aimed to determine whether ELP or biometry at age 10½ years correlated with PE in children enrolled in the Infant Aphakia Treatment Study (IATS). METHODS: We compared the measured refraction of eyes randomized to primary IOL implantation to the "predicted refraction" calculated by the Holladay 1 formula, based on biometry at age 10½ years. Eyes with incomplete data or IOL exchange were excluded. The PE (predicted - measured refraction) and absolute PE were calculated. Measured anterior chamber depth (ACD) was used to assess the effect of ELP on PE. Multiple regression analysis was performed on absolute PE versus axial length, corneal power, rate of refractive growth, refractive error, and best-corrected visual acuity. RESULTS: Forty-three eyes were included. The PE was 0.63 ± 1.68 D; median absolute PE, 0.85 D (IQR, 1.83 D). The median absolute PE was greater when the measured ACD was used to calculate predicted refraction instead of the standard A-constant (1.88 D [IQR, 1.72] D vs 0.85 D [IQR, 1.83], resp. [P = 0.03]). Absolute PE was not significantly correlated with any other parameter. CONCLUSIONS: Variations in ELP did not contribute significantly to PE 10 years after infant cataract surgery.
Yonamine S, Ton L, Rose-Nussbaumer J, Ying G-S, Ahmed IIK, Chen TC, Weiner A, Gedde SJ, Han Y. Survey of the American Glaucoma Society Membership on Current Glaucoma Drainage Device Placement and Postoperative Corticosteroid Use. Clin Ophthalmol 2022;16:2305-2310.Abstract
Purpose: To assess practice patterns and opinions of glaucoma specialists regarding glaucoma drainage device tube shunt placement and post-operative anti-inflammatory medication use. We also assess the perceived need for a randomized control trial to compare them. Patients and Methods: An online survey was distributed to a group of glaucoma specialists from the American Glaucoma Society via the American Glaucoma Society forum from April to August 2021. Results: One hundred and twenty-eight responses were included. Ninety percent placed tubes in the anterior chamber. Sixty-one percent reported that evidence suggested the superiority of sulcus tube placement over the anterior chamber, whereas 34% reported there was not enough evidence to suggest superiority of either in preventing endothelial cell loss. Comparing these techniques for intraocular pressure control, 49% reported evidence suggested sulcus tube placement superiority whereas 46% reported there was not enough evidence. Over 40% of respondents reported that they were either unfamiliar with literature or that there was not enough evidence to support the superiority of difluprednate 0.05% over prednisolone 1% for post-operative use in preventing endothelial cell loss and for intraocular pressure control. Ninety percent and 81% of respondents respectively would benefit from randomized control trials comparing outcomes of anterior chamber vs sulcus tube placement and post-operative corticosteroid usage. Conclusion: Most glaucoma specialists surveyed place glaucoma drainage device tube in the anterior chamber over the sulcus. A randomized control trial to determine optimal tube placement and post-operative anti-inflammatory medication use for preventing endothelial cell loss would change current glaucoma drainage device practice patterns.
Kang JH, Wang M, Frueh L, Rosner B, Wiggs JL, Elze T, Pasquale LR. Cohort Study of Race/Ethnicity and Incident Primary Open-Angle Glaucoma Characterized by Autonomously Determined Visual Field Loss Patterns. Transl Vis Sci Technol 2022;11(7):21.Abstract
Purpose: We evaluated racial/ethnic differences in primary open-angle glaucoma (POAG) defined by machine-learning-derived regional visual field (VF) loss patterns. Methods: Participants (N = 209,036) from the Nurses' Health Study (NHS; 1980-2018), Nurses' Health Study II (NHS2; 1989-2019), and Health Professionals Follow-Up Study (HPFS; 1986-2018) who were ≥40 years of age and free of glaucoma were followed biennially. Incident POAG cases (n = 1946) with reproducible VF loss were confirmed with medical records. Total deviation information from the earliest reliable glaucomatous VF for each POAG eye (n = 2564) was extracted, and machine learning analyses were used to identify optimal solutions ("archetypes") for regional VF loss patterns. Each POAG eye was assigned a VF archetype based on the highest weighting coefficient. Multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using per-eye Cox proportional hazards models. Results: We identified 14 archetypes: four representing advanced loss patterns, nine of early loss, and one of no VF loss. Compared to non-Hispanic whites, black participants had higher risk of early VF loss archetypes (HR = 1.98; 95% CI, 1.48-2.66) and even higher risk for advanced loss archetypes (HR = 6.17; 95% CI, 3.69-10.32; P-contrast = 0.0002); no differences were observed for Asians or Hispanic whites. Hispanic white participants had significantly higher risks of POAG with paracentral defects and advanced superior loss; black participants had significantly higher risks of all advanced loss archetypes and three early loss patterns, including paracentral defects. Conclusions: Blacks, compared to non-Hispanic whites, had higher risks of POAG with early central and advanced VF loss. Translational Relevance: In POAG, risks of VF loss regional patterns derived from machine learning algorithms showed racial differences.
Gomez A, Mercado C, Venkateswaran N, de la Sen-Corcuera B, Miller D, Dubovy S, Salero E, Sabater AL. Brief incubation of corneal grafts in activated platelet rich plasma enhances corneal endothelial cell survival and regeneration. Exp Eye Res 2022;220:109100.Abstract
Corneal transplantation is the most frequent organ transplantation worldwide. Unfortunately, corneal graft failure is common and endothelial decompensation is considered the major cause. Corneal endothelial cells (CECs) lack the capacity to reproduce, and perioperative and postoperative endothelial cell loss remains a significant challenge associated with corneal graft viability. Therefore, strategies to preserve CEC density are critical to extend graft survival. Activated platelet rich plasma (aPRP), a product extracted from autologous blood, has both antioxidant and regenerative properties. aPRP eye drops have shown effectiveness in the treatment of corneal pathologies such as ulcers, dry eye, and burns. Our purpose is to determine the protective and regenerative effect of aPRP on corneal grafts by evaluating aPRP's effect on the survival and proliferation of human CECs. Human corneal grafts were incubated in aPRP for 15 min to assess the activation of the CEC pAkt survival pathway as measured by ELISA. Evaluation of the protective effect of aPRP was made using an apoptotic model, which simulated oxidative stress conditions. Expression of apoptotic markers was measured using ELISA and endothelial cell viability was determined by optical microscopy. The CEC proliferation rate was measured in vitro with Ki-67 staining. Corneal graft gross structure was evaluated by Hematoxylin & Eosin and Masson trichrome staining. Our results indicate that a short incubation of human corneal grafts in aPRP protects CECs from apoptosis by upregulating the pAkt survival pathway and promoting CEC proliferation. Additionally, aPRP incubation does not induce histological changes in the grafts. A brief pre-treatment of human corneal grafts in aPRP may be beneficial for transplant longevity, as it protects CECs from apoptosis by upregulating intracellular survival pathways and promoting proliferation. In addition, this approach appears to be safe and has the potential to improve surgical outcomes following corneal transplantation.
Simpson FC, Islam MM, Buznyk O, Edin E, Groleau M, Kozak-Ljunggren M, Magrelli FM, AbuSamra DB, Argüeso P, Chodosh J, Liszka A, Fagerholm P, Griffith M. Electron-Beam Irradiated Recombinant Human Collagen-Phosphorylcholine Corneal Implants Retain Pro-Regeneration Capacity. Front Bioeng Biotechnol 2022;10:883977.Abstract
Sterilization of biodegradable, collagen-based implants is challenging as irradiation sterilization methods can alter their mechanical properties. Electron beam (EB) irradiation is a terminal sterilization method that has been used for biologically-derived implants. Here, recombinant human collagen type III-phosphorylcholine (RHCIII-MPC) hydrogels were irradiated with EB doses of 17, 19, or 21 kGy and their subsequent biocompatibility and ability to promote regeneration in rabbit corneas was evaluated. Unirradiated hydrogels stored in 1% chloroform in phosphate-buffered saline (C-PBS) were the controls. There were no significant differences between irradiated and non-irradiated samples in optical or physical properties (tensile strength, modulus, elasticity), or the ability to support cell growth. However, irradiated implants were more sensitive to high levels of collagenase than unirradiated controls and the C-PBS implants had increased cell growth compared to EB and controls at 72 h. Corneal implants e-beamed at 17 kGy or e-beamed and subsequently frozen (EB-F) to increase shelf-life showed no adverse biological effects of the irradiation. EB, EB-F, and C-PBS implanted corneas all rapidly re-epithelialized but showed mild neovascularization that resolved over 6 months. The regenerated neo-corneas were transparent at 6 months post-operation. In vivo confocal microscopy confirmed normal morphology for the epithelium, stroma, sub-basal nerves and unoperated endothelium. Histology showed that all the regenerated corneas were morphologically similar to the normal. Immunohistochemistry indicated the presence of a differentiated corneal epithelium and functional tear film. In conclusion, the e-beamed corneal implants performed as well as non-irradiated control implants, resulting in fully regenerated neo-corneas with new nerves and without blood vessels or inflammation that may impede vision or corneal function. Therefore, a complete validation study to establish EB irradiation as an effective means for corneal implant sterilization prior to clinical application is necessary as a next step.
Littau JL, Velilla L, Hase Y, Villalba-Moreno ND, Hagel C, Drexler D, Osorio Restrepo S, Villegas A, Lopera F, Vargas S, Glatzel M, Krasemann S, Quiroz YT, Arboleda-Velasquez JF, Kalaria R, Sepulveda-Falla D. Evidence of beta amyloid independent small vessel disease in familial Alzheimer's disease. Brain Pathol 2022;:e13097.Abstract
We studied small vessel disease (SVD) pathology in Familial Alzheimer's disease (FAD) subjects carrying the presenilin 1 (PSEN1) p.Glu280Ala mutation in comparison to those with sporadic Alzheimer's disease (SAD) as a positive control for Alzheimer's pathology and Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) bearing different NOTCH3 mutations, as positive controls for SVD pathology. Upon magnetic resonance imaging (MRI) in life, some FAD showed mild white matter hyperintensities and no further radiologic evidence of SVD. In post-mortem studies, total SVD pathology in cortical areas and basal ganglia was similar in PSEN1 FAD and CADASIL subjects, except for the feature of arteriosclerosis which was higher in CADASIL subjects than in PSEN1 FAD subjects. Further only a few SAD subjects showed a similar degree of SVD pathology as observed in CADASIL. Furthermore, we found significantly enlarged perivascular spaces in vessels devoid of cerebral amyloid angiopathy in FAD compared with SAD and CADASIL subjects. As expected, there was greater fibrinogen-positive perivascular reactivity in CADASIL but similar reactivity in PSEN1 FAD and SAD groups. Fibrinogen immunoreactivity correlated with onset age in the PSEN1 FAD cases, suggesting increased vascular permeability may contribute to cognitive decline. Additionally, we found reduced perivascular expression of PDGFRβ AQP4 in microvessels with enlarged PVS in PSEN1 FAD cases. We demonstrate that there is Aβ-independent SVD pathology in PSEN1 FAD, that was marginally lower than that in CADASIL subjects although not evident by MRI. These observations suggest presence of covert SVD even in PSEN1, contributing to disease progression. As is the case in SAD, these consequences may be preventable by early recognition and actively controlling vascular disease risk, even in familial forms of dementia.
Glonek T, Snogren T, Schmidt SY, Hearn SL, Isreb MA, Greiner JV. Phosphatic metabolism in dark- and light-adapted rat retinas. Exp Eye Res 2022;221:109141.Abstract
This study defines retinal phosphatic metabolites and their adjustment to illumination in rat retinas under conditions that preserve retinal function. Metabolic data are measured using high-performance liquid chromatography (HPLC) and 31P nuclear magnetic resonance (31P NMR) spectroscopy after 10 min of light exposure in vivo compared with retinas from dark-adapted rats. Multiple high-energy and low-energy phosphatic metabolites of intermediary metabolism were quantified. The concentration of the high-energy phosphate adenosine triphosphate (ATP) remained unchanged from dark- to light-adaptation. Under the same conditions the concentrations of the high-energy phosphates guanosine triphosphate (GTP) and creatine phosphate increased, whereas the inorganic phosphate decreased. Comparing dark-adapted controls with retinas light-adapted either in vitro or in vivo, the evidence is consistent with a light-dependent increase in GTP and a decrease in cyclic guanosine monophosphate. Although cyclic adenosine monophosphate (cAMP) levels were lower in retinas light-adapted in vivo than in the dark-adapted controls, this did not seem to be an effect of light, as cAMP levels decreased similarly after 10 min incubation in dark or light in parallel with recovery of ATP/adenosine diphosphate ratios. This study: (1) reports on retinal metabolic changes with adjustment in illumination, (2) provides baseline measurements of retinal phosphatic metabolites in whole retinas, and (3) reports on the validity of chromatographic and spectroscopic methods used for studying retinal metabolism establishing a high correlation among measurements made using HPLC and 31P NMR.
Islam MM, Chivu A, AbuSamra DB, Saha A, Chowdhuri S, Pramanik B, Dohlman CH, Das D, Argüeso P, Rajaiya J, Patra HK, Chodosh J. Crosslinker-free collagen gelation for corneal regeneration. Sci Rep 2022;12(1):9108.Abstract
Development of an artificial cornea can potentially fulfil the demand of donor corneas for transplantation as the number of donors is far less than needed to treat corneal blindness. Collagen-based artificial corneas stand out as a regenerative option, having promising clinical outcomes. Collagen crosslinked with chemical crosslinkers which modify the parent functional groups of collagen. However, crosslinkers are usually cytotoxic, so crosslinkers need to be removed from implants completely before application in humans. In addition, crosslinked products are mechanically weak and susceptible to enzymatic degradation. We developed a crosslinker free supramolecular gelation strategy using pyrene conjugated dipeptide amphiphile (PyKC) consisting of lysine and cysteine; in which collagen molecules are intertwined inside the PyKC network without any functional group modification of the collagen. The newly developed collagen implants (Coll-PyKC) are optically transparent and can effectively block UV light, are mechanically and enzymatically stable, and can be sutured. The Coll-PyKC implants support the growth and function of all corneal cells, trigger anti-inflammatory differentiation while suppressing the pro-inflammatory differentiation of human monocytes. Coll-PyKC implants can restrict human adenovirus propagation. Therefore, this crosslinker-free strategy can be used for the repair, healing, and regeneration of the cornea, and potentially other damaged organs of the body.

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