Autologous serum eye drops for ocular surface disorders

Autologous Serum Eye Drops Diluted with Cyclosporine A 0.05% and Sodium Hyaluronate 0.1%: An Experimental Comparative Study

PURPOSE

The purpose of this study was to assess in-vitro efficacy of a suffusion of autologous serum withcyclosporine 0.05% (CsA) and sodium hyaluronate 0.1% (SH).

METHODS

The expression of proinflammatory markers interleukin 6 (IL-6) and TNF-Alpha (TNF-α) in limbal epithelial cells was evaluated. Also, assessment of the stability of epithelial growth factor and transforming growth factor-beta (EGF, TGF-β) in the 50% combinations with autologous serum (AS) was done. The characteristics (pH, density, osmolality) of the two combinations were also evaluated. Additionally, cytotoxicity effect of given test compounds was evaluated on human limbal epithelial cells (LEpiC).

RESULTS

The percentage of cells expressing IL-6 subjected to AS + SH and AS + CsA were 6.23% and 5.69% respectively. There was no significant difference in percentage of cells expressing TNF-α between the formulations (5.87%, 5.83% respectively). The growth factors; EGF and TGF-β remained stable forone month duration (on 2 and 4 weeks) at 4 °C without significant difference between the time intervals tested. The results of MTT assay suggested that limbal epithelial cells treated with AS + CsA and AS + SH combinations showed minimal toxicity however it was not significant statistically (p ≤ 0.05).

CONCLUSION

Two test combinations (AS + CsA, AS + SH) showed stable growth factors (EGF, TGF-β) and good anti-inflammatory property against pro-inflammatory markers. Also, the 2 combinations were found safe on cultured limbal epithelial cells. The novel combination of autologous serum in CsA may provide added benefit in dry eye disease (DED) through their combined anti-inflammatory and epitheliotropic effects.

Allogenic and autologous nondiluted serum eye drops-validation strategy compliant with good manufacturing practice

BACKGROUND AND AIMS

Serum eye drops alleviate ocular symptoms of diseases such as sicca syndrome, or chronic graft-versus-host disease. This study was designed for good manufacturing practice validation of our standard manufacturing, storage and transport processes for both autologous and allogenic SEDs. Specifications of quality parameters are lacking and were aimed to be defined.

METHODS

Using sterile collected, coagulated whole blood, serum was separated by centrifugation and filled into single-use eye drop applicator vials. Quality control tests included visual inspection, sterility, leukocyte concentration, pH, vitamin A, TGF-ß and VEGF-A. Samples were collected after manufacture and after 24 h and 6 months of frozen storage (-20°C). Sterility testing was performed after opening the SED applicators at specified intervals. For transport validation, SEDs were packed in insulated transport bags and stored at 20-24°C and 30-32°C for 8 h.

RESULTS

Vitamin A, TGF-ß and VEGF-A assays showed no difference in concentration between fresh and 24 h frozen serum. All specifications for pH (aim 7.4) and cellular contamination were met and microbiological contamination tests were negative. Shelf-life was defined as 6 months at -20°C. Once opened, the product must be used within 24 h to avoid bacterial outgrowth. Transporting frozen SEDs from the manufacturer via a local pharmacy to the patient within a maximum of 4 h was demonstrated.

CONCLUSIONS

The GMP compliance of our production, storage and transport processes for autologous and allogenic SEDs was successfully validated. 100% serum eye drops in single-use applicators can be safely used for up to 24 h after opening.

Corneal neuropathic pain: a review to inform clinical practice

Corneal neuropathic pain (CNP) is a poorly defined disease entity characterised by an aberrant pain response to normally non-painful stimuli and categorised into having peripheral and central mechanisms, with the former responding to instillation of topical anaesthetic. CNP is a challenging condition to diagnose due to numerous aetiologies, an absence of clinical signs and ancillary tests (in vivo confocal microscopy and esthesiometry), lacking the ability to confirm the diagnosis and having limited availability. Symptomatology maybe mirrored by severe and chronic forms of dry eye disease (DED), often leading to misdiagnosis and inadequate treatment. In practice, patients with suspected CNP can be assessed with questionnaires to elicit symptoms. A thorough ocular assessment is also performed to exclude any co-existent ocular conditions. A medical and mental health history should be sought due to associations with autoimmune disease, chronic pain syndromes, anxiety and depression. Management begins with communicating to the patient the nature of their condition. Ophthalmologists can prescribe topical therapies such as autologous serum eyedrops to optimise the ocular surface and promote neural regeneration. However, a multi-disciplinary treatment approach is often required, including mental health support, particularly when there are central mechanisms. General practitioners, pain specialists, neurologists and psychologists may be needed to assist with oral and behavioural therapies. Less data is available to support the safety and efficacy of adjuvant and surgical therapies and the long-term natural history remains to be determined. Hence clinical trials and registry studies are urgently needed to fill these data gaps with the aim to improve patient care.

Comparison of autologous serum and platelet-rich plasma in the treatment of severe dry eye and persistent epithelial defects

PURPOSE

To compare the efficacy of topical autologous serum and platelet-rich plasma (PRP) in patients with severe dry eye and persistent epithelial defects.

METHODS

Sixty-seven eyes of 42 patients including 12 Sjogren, 11 meibomian gland dysfunction, 8 post penetrating keratoplasty, 5 acne rosacea, 5 chemical burn and 3 neurotophic keratopathy were analyzed. Best corrected visual acuity, Schirmer, Ocular Surface Disease Index (OSDI), tear break-up time, Oxford staining scores were measured before the treatment and 1 month. One month scores of two groups were compared.

RESULTS

Thirty three eyes received autologous serum and 34 received PRP. There was no statistically significant differences between two groups in ocular surface parameters at baseline. Statistically significant improvements were achieved in both groups in all parameters at 1 month (p < 0.05). Schirmer score improved from 7.9 ± 7.6 to 10.6 ± 8.4 mm in autologous serum (p < 0.001) and from 10.9 ± 9.5 to 13.3 ± 10.1 in PRP (p < 0.001); BUT from 4.3 ± 2.7 to 6.7 ± 3.4 s (p < 0.001) and 4.5 ± 3.0 to 6.0 ± 3.6 (p < 0.001); OSDI from 47.7 ± 14.7 to 25.7 ± 11.0 (p < 0.001) and from 54.1 ± 17.3 to 26.8 ± 11.0 (p < 0.001); Oxford score from 4.0 ± 1.0 to 1.3 ± 1.1 in (p < 0.001) and 3.9 ± 0.9 to 1.6 ± 1.3 (p < 0.001) respectively. Significant visual improvement was achieved with PRP from 0.81 ± 0.73 LogMAR to 0.72 ± 0.63 (p = 0.025), whereas insignificant with serum from 0.60 ± 0.65 to 0.57 ± 0.67 (p = 0.147). Mean epithelial healing time was 6.7 ± 4.7 (2-14) days in serum and 3.6 ± 1.9 (2-7) in PRP (p = 0.195).

CONCLUSIONS

Both treatments are equally effective in severe dry eye and persistent epithelial defects. Although, visual gain is higher in PRP, autologous serum may be preferable due to low cost.

Lagophthalmos-induced corneal perforation in a patient with congenital erythropoietic porphyria

Congenital erythropoietic porphyria (CEP) is a rare autosomal recessive disorder in which the activity of uroporphyrinogen III synthase (UROS) is decreased. This results in the accumulation of photoreactive porphyrinogens, primarily in the skin and bone marrow. We describe a case of a patient with CEP who initially presented with scarring and shortening of the anterior and posterior lid lamella, which led to the development of lagophthalmos. Vascularized hyperkeratotic plaques in both corneas were also present. Despite treatment with topical ocular surface lubricants, corneal perforation with iris and uvea prolapse developed and evisceration of the right eye under local anesthesia was performed. The presented case suggests that despite topical therapy, ocular complications may exacerbate requiring surgical intervention, especially in the presence of lagophthalmos.

Blood-Derived Eye Drops for the Treatment of Corneal Neuropathic Pain

Blood-derived preparations, including autologous or allogenic serum, umbilical cord serum/plasma, and platelet-rich plasma eye drops, contain various growth factors, cytokines, and immunoglobulins that resemble natural tears. These components play important roles in corneal cell migration, proliferation, and wound healing. Blood-derived eye drops have demonstrated clinical effectiveness across a spectrum of ocular surface conditions, encompassing dry eye disease, Sjögren's syndrome, graft-versus-host disease, and neuropathic corneal pain (NCP). Currently, management of NCP remains challenging. The emergence of blood-derived eye drops represents a promising therapeutic approach. In this review, we discuss the benefits and limitations of different blood-derived eye drops, their mechanisms of action, and treatment efficacy in patients with NCP. Several studies have demonstrated the clinical efficacy of autologous serum eye drops in relieving pain and pain-like symptoms, such as allodynia and photoallodynia. Corneal nerve parameters were also significantly improved, as evidenced by increased nerve fiber density, length, nerve reflectivity, and tortuosity, as well as a decreased occurrence of beading and neuromas after the treatment. The extent of nerve regeneration correlated with improvement in patient-reported photoallodynia. Cord plasma eye drops also show potential for symptom alleviation and corneal nerve regeneration. Future directions for clinical practice and research involve standardizing preparation protocols, establishing treatment guidelines, elucidating underlying mechanisms, conducting long-term clinical trials, and implementing cost-effective measures such as scaling up manufacturing. With ongoing advancements, blood-derived eye drops hold promise as a valuable therapeutic option for patients suffering from NCP.

Post-refractive Surgery Dry Eye: A Systematic Review Exploring Pathophysiology, Risk Factors, and Novel Management Strategies

Dry eye disease frequently manifests following corneal refractive procedures, significantly impacting patients' quality of life. This review systematically synthesizes current evidence on the pathophysiological mechanisms, risk factors, and therapeutic interventions for post-refractive surgery dry eye. Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, a systematic review of literature published until August 2023 was conducted, focusing on post-refractive surgery dry eye. Eighteen relevant studies were identified through screening and eligibility assessment. A qualitative synthesis of outcomes was performed using narrative and thematic analysis methods. Surgically induced neurotrophic deficiency, stemming from nerve transection, triggers a cascade of events including apoptosis, inflammation, and lacrimal dysfunction, ultimately leading to tear film instability. Risk factors such as female gender, thyroid eye disease, meibomian gland dysfunction, higher ablation depths, and the use of LASIK over surface ablation exacerbate the condition. While conventional treatments like artificial tears provide temporary relief, emerging interventions such as nerve growth factors, matrix metalloproteinase inhibitors, serum eye drops, and specialized contact lenses show promise in promoting nerve regeneration and epithelial healing. Strategies such as customized ablation profiles, smaller optical zones, and nerve-sparing techniques like small incision lenticule extraction demonstrate potential advantages. A multifaceted therapeutic approach targeting neuroprotection, anti-inflammatory mechanisms, and tear film stabilization is imperative for effectively managing post-refractive surgery dry eye. Future research should focus on evaluating prognostic biomarkers, exploring precision medicine approaches, and investigating neuroprotective adjuvants to further enhance treatment outcomes.

Five-Year Risk and Safety Profile of Autologous Serum Eye Drop Therapy

PURPOSE

To evaluate the risk and safety profile of autologous serum eye drop therapy in clinical routine over a period of 5 years.

METHODS

This retrospective study involved all patients treated with autologous serum between July 2014 and December 2019 at a tertiary ophthalmic referral center. The electronic patient record system was searched for all patients with autologous serum eye drop therapy at any time point. These records were subsequently searched for keywords such as infectious keratitis, corneal ulcer, conjunctivitis, or endophthalmitis at any recorded contact. The probability of an association between the therapy with autologous serum eye drops and infectious complications was investigated independently by three corneal specialists and rated as likely, potential, or unlikely.

RESULTS

In total, 752 patients were treated with autologous serum eye drops between July 2014 and December 2019. There were 5 384 batches with a total of 107 680 bottles of serum eye drops that had been produced and dispensed for these patients during this period. The records of 291 patient showed a combination of autologous serum therapy and at least one keyword for infectious diseases. In 288 patients, individual case analyses revealed an unlikely association between the therapy and infection, as their infectious episodes occurred either before the start of the therapy, more than 1 month after the therapy ceased, or in the contralateral untreated eye in the case of unilateral therapy. Three cases of infectious keratitis were classified as potentially associated with autologous serum therapy. However, all three patients suffered from chronic anterior eye diseases with a high risk of spontaneous infectious complications independent of therapy with autologous eye drops. None of the infectious events was rated as being likely due to the serum eye drops.

CONCLUSIONS

Serum eye drops are often used in patients with severe or chronic anterior eye diseases with an intrinsic risk of infectious diseases. Despite these preexisting risk factors, autologous serum eye drops can be considered safe, even in patients with a compromised ocular surface.

Platelet-rich plasma for treating dry eye disease - A systematic review and meta-analysis

PURPOSE

Dry eye disease has public health and economic significance. Platelet-rich plasma is rich in anti-inflammatory agents and growth factors, both beneficial for ocular surface repair. This study aimed to conduct a systematic review and meta-analysis to summarize the benefits of platelet-rich plasma for treating dry eye disease and its adverse effects.

METHODS

Prospective comparative studies using platelet-rich plasma as monotherapy for dry eye disease were included for efficacy assessment. Before-after studies were included for adverse events assessment. Data sources included PubMed, Google Scholar, Web of Science, and Scopus. A systematic review and meta-analysis protocol was pre-registered on PROSPERO (CRD42022347982). PRISMA guidelines were followed. The National Health Institute (NIH) quality assessment tool for before-after studies, the Cochrane risk of bias tool (RoB2), and the methodological index for non-randomized studies were used to assess the risk of bias. Heterogeneity was assessed using the I2 statistic.

RESULTS

19 studies (10 comparative and 9 before-after) were included in the systematic review and meta-analysis. The occurrence rate of adverse effects was 2.6 % (95 % CI: 0.5 - 4.7). The pooled standardized mean difference (SMD) for dry eye symptoms was 0.81 (95 % CI: 0.25 - 1.37; I2 = 82 %; p < 0.00001; Z = 2.84, p = 0.004); tear quality was 0.44 (95 % CI: 0.06 - 0.81; I2 = 67 %; p = 0.003; Z = 2.26, p = 0.02); tear quantity was 0.45 (95 % CI: 0.03 - 0.88; I2 = 74 %; p = 0.0003; Z = 2.10, p = 0.04); and corneal staining 0.72 (95 % CI: 0.14 - 1.30; I2 = 85 %; p < 0.00001; Z = 2.43, p = 0.02).

CONCLUSION

The current study shows that platelet-rich plasma is efficacious in managing dry eye disease, significantly reducing dry eye signs and symptoms. Such significant improvements could translate to improved quality of life.

Current Advances in Regenerative Strategies for Dry Eye Diseases: A Comprehensive Review

Dry eye disease (DED) is an emerging health issue affecting millions of individuals annually. Ocular surface disorders, such as DED, are characterized by inflammation triggered by various factors. This condition can lead to tear deficiencies, resulting in the desiccation of the ocular surface, corneal ulceration/perforation, increased susceptibility to infections, and a higher risk of severe visual impairment and blindness. Currently, the clinical management of DED primarily relies on supportive and palliative measures, including the frequent and lifelong use of different lubricating agents. While some advancements like punctal plugs, non-steroidal anti-inflammatory drugs, and salivary gland autografts have been attempted, they have shown limited effectiveness. Recently, there have been promising developments in the treatment of DED, including biomaterials such as nano-systems, hydrogels, and contact lenses for drug delivery, cell-based therapies, biological approaches, and tissue-based regenerative therapy. This article specifically explores the different strategies reported so far for treating DED. The aim is to discuss their potential as long-term cures for DED while also considering the factors that limit their feasibility and effectiveness. These advancements offer hope for more effective and sustainable treatment options in the future.

Biological effects of stored platelet-rich plasma eye-drops in corneal wound healing

BACKGROUND/AIMS

This study aimed to assess the efficacy and sterility of stored platelet-rich plasma (PRP) eye-drops for corneal epithelial wound healing compared with those of autologous serum (AS) eye-drops.

METHODS

At our single institution, PRP and AS eye-drops were prepared using peripheral blood obtained from six healthy volunteers and stored at 4°C. Platelet and leucocyte counts and transforming growth factor (TGF)-β1, epidermal growth factor (EGF), and fibronectin levels were assessed during storage for up to 4 weeks. Sterility was assessed by culturing 4-week poststorage samples. PRP, AS, and phosphate-buffered saline (PBS) eye-drop efficacies were compared using corneal epithelial wound healing assays in vitro and in vivo and monitoring wound areas under a microscope every 3 hours.

RESULTS

Higher platelet and lower leucocyte counts were seen in PRP than in whole blood on the day of preparation. After storage, TGF-β1, EGF, and fibronectin levels were significantly higher in PRP than in AS eye-drops. In vitro and in vivo, PRP eye-drops used on the day of preparation significantly promoted corneal epithelial wound healing compared with PBS. Moreover, PRP eye-drops stored for 4 weeks significantly promoted corneal wound healing compared with PBS and AS eye-drops.

CONCLUSION

PRP eye-drops stored at 4°C for 4 weeks promoted corneal epithelial wound healing with higher levels of growth factors than those observed in AS eye-drops, while maintaining sterility, suggesting that this preparation satisfies the unmet medical needs in the treatment of refractory keratoconjunctival epithelial disorders.

Allogeneic Serum Eye Drops: A Randomized Clinical Trial to Evaluate the Clinical Effectiveness of Two Drop Sizes

INTRODUCTION

Allogeneic serum from blood donors is starting to be used to treat patients with dry eye disease (DED). However, the optimal dose is not known. We therefore aimed to evaluate the clinical efficaciousness and user-friendliness of micro-sized versus conventional-sized allogeneic serum eye drops (SEDs).

METHODS

In a randomized trial, patients with DED first receive micro-sized SEDs (7 µl/unit) for 1 month, followed by a 1-month washout, before receiving conventional-sized SEDs (50 µl/unit) for 1 month; or vice versa. The primary endpoint was the Ocular Surface Disease Index (OSDI) score. Secondary endpoints were tear break-up time (TBT), tear production (TP), and presence of corneal punctate lesions (CP). The user-friendliness of both application systems was also compared. A linear mixed model for cross-over design was applied to compare both treatments.

RESULTS

Forty-nine patients completed the trial. The mean OSDI score significantly improved from 52 ± 3 to 41 ± 3 for micro-sized SEDs, and from 54 ± 3 to 45 ± 3 for conventional-sized SEDs. Non-inferiority (margin = 6) of micro-sized SEDs was established. We demonstrate a significant improvement for TBT in case of conventional-sized SEDs and for CP in both treatment groups. TP trended towards an improvement in both treatment groups. The user-friendliness of the conventional drop system was significantly higher.

CONCLUSIONS

For the first time, non-inferiority of micro-sized allogeneic SEDs was established. The beneficial effect of both SED volumes was similar as measured by the OSDI score. Although user-friendliness of the micro drop system was significantly lower, it is an attractive alternative as it saves valuable donor serum.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT03539159).

Efficacy and safety of platelet-rich plasma and autologous-serum eye drops for dry eye in primary Sjögren's syndrome: a randomized trial

We compared the efficacy and safety of autologous-serum (AS) and platelet-rich plasma (PRP) eye drops for dry eye (DE) treatment in primary Sjögren's syndrome (SS). This prospective, randomized, double-blinded clinical study included patients diagnosed with primary SS DE. Thirty-eight participants were randomly assigned to the AS or PRP groups. Corneal and conjunctival staining scores, Schirmer I test, tear film break-up time (TBUT), and ocular surface disease index (OSDI) scores were evaluated at 4 and 12 weeks. Conjunctival impression cytology (CIC) metaplasia grade and goblet cell density grade at 12 weeks were compared with those at baseline. Corneal and conjunctival staining scores and TBUT significantly improved at 4 and 12 weeks in both groups (all p < 0.005). No significant difference between the AS and PRP groups was observed at 4 and 12 weeks. The Schirmer I values, OSDI scores, CIC metaplasia grade, and goblet cell density grade did not significantly change at 4 and 12 weeks in either group. Both AS and PRP eye drops are effective for primary SS DE without a significant difference. Considering that the preparation time of PRP is shorter than that of AS, PRP can be a good alternative treatment for primary SS DE.

New developments in the management of persistent corneal epithelial defects

A persistent epithelial defect (PED) is a corneal epithelial defect that failed to heal after 2weeks. It is a condition that carries much morbidity, and our understanding of PED remains poor, with current treatment methods often having unsatisfactory outcomes. With PEDs becoming more prevalent, more efforts are required to establish reliable treatment modalities. Our reviews describe the causes of PEDs and the different approaches developed to manage them, as well as their associated limitations. Emphasis is placed on understanding various advances in the development of new treatment modalities. We have also described a case of a woman with a background of graft-versus-host disease on long-term topical corticosteroids who developed complicated PED involving both eyes. The current approach to managing PEDs generally involves exclusion of an active infection, followed by treatment modalities that aim to encourage corneal epithelial healing. Success rates, however, remain far from desirable, as treatment remains challenging due to multiple underlying etiologies. In summary, advances in the development of new therapies may be able to facilitate progress in the understanding and treatment of PED.

Randomized controlled trial on the efficacy and safety of autologous serum eye drops in dry eye syndrome

BACKGROUND

Autologous serum eye drops (ASEDs), a novel treatment derived from blood serum, have emerged as a groundbreaking solution for managing dry eye syndrome (DES). These drops have shown significant promise in relieving the distressing symptoms of DES. This study aimed to evaluate the safety and effectiveness of ASEDs compared to traditional treatments, which often prove inadequate or result in unwanted side effects, particularly in individuals with moderate-to-severe DES.

AIM

To evaluate whether ASEDs are safer and more effective than conventional artificial tears in the treatment of moderate-to-severe DES.

METHODS

This multi-centered randomized controlled trial included 240 patients with moderate-to-severe DES from three ophthalmology clinics in China. They were randomly assigned to receive either ASEDs or artificial tears for 12 wk. The primary outcome was the change in the ocular surface disease index (OSDI) score, with secondary outcomes including tear break-up time (TBUT), Schirmer I test, corneal fluorescein staining (CFS), and conjunctival impression cytology (CIC). Statistics analysis was performed using an analysis of covariance with adjustments made for baseline values.

RESULTS

Our findings revealed that both ASEDs and artificial tears significantly improved the OSDI score, TBUT, Schirmer I test, CFS, and CIC from baseline to week 12. The ASEDs group showed significantly greater improvement in all these measures than the artificial tears group (all P values < 0.05). The average difference in the OSDI score between the two cohorts was -10.3 (95% confidence interval: -13.6 to -7.0), indicating a substantial improvement in the ASEDs group. The occurrence of adverse events was comparable between cohorts, with no reports of severe adverse events.

CONCLUSION

ASEDs are more effective and safer than artificial tears for mitigating symptoms of moderate-to-severe DES. ASEDs could be an alternative/supplementary therapy for patients with DES less responsive to traditional treatments.

Recent advances in drug treatments for dry eye disease

INTRODUCTION

Dry eye disease (DED) is a common ocular condition with a significant impact on patients' quality of life. Conventional treatments include behavioral changes, tear substitutes, and anti-inflammatory agents; however, recent advances in the understanding of DED pathogenesis have opened the way to the development of novel treatment strategies able to target several pathways involved in the onset and persistence of DED.

AREAS COVERED

Literature search was conducted on PubMed and Scopus around the term 'dry eye disease' and others involving its pathophysiology and therapeutic strategy. The primary focus was on recent drugs approved by FDA or under investigation in phase 3 clinical trials. Google and ClinicalTrials.gov were used for obtaining information about the status of FDA approval and ongoing clinical trials.

EXPERT OPINION

Due to its multifaced pathogenesis, DED management is often challenging, and patients' needs are frequently unmet. Recently, several novel treatments have been either FDA-approved or studied in late-phase trials. These novel drugs target-specific biological components of the ocular surface and reduce inflammation and ocular pain. Additionally, new drug delivery systems allow for increased bioavailability, improve effective dosing, and minimize ocular side effects. These advances in drug therapies show real promise for better management of DED patients.

Future directions in managing aniridia-associated keratopathy

Congenital aniridia is a panocular disorder that is typically characterized by iris hypoplasia and aniridia-associated keratopathy (AAK). AAK results in the progressive loss of corneal transparency and thereby loss of vision. Currently, there is no approved therapy to delay or prevent its progression, and clinical management is challenging because of phenotypic variability and high risk of complications after interventions; however, new insights into the molecular pathogenesis of AAK may help improve its management. Here, we review the current understanding about the pathogenesis and management of AAK. We highlight the biological mechanisms involved in AAK development with the aim to develop future treatment options, including surgical, pharmacological, cell therapies, and gene therapies.

Can Serum Drops Containing Doxycycline Provide a Supplemental Anti-Bacterial Effect in the Treatment of Bacterial Keratitis?

PURPOSE

Systemic doxycycline has been prescribed to reduce inflammation and enhance corneal healing in bacterial keratitis. Topical autologous serum drops (ASD) containing doxycycline following oral supplementation may additionally confer an anti-bacterial effect. The potential of this supplementation was evaluated by determining the in vitro susceptibility of bacterial keratitis isolates to doxycycline.

METHODS

The minimum inhibitory concentrations (MICs) of doxycycline against 100 bacterial keratitis isolates were determined using Etests. Twenty-seven Staphylococcus aureus, ten coagulase-negative Staphylococci, six Streptococcus pneumoniae, seven viridans group streptococci, seven other Gram-positive bacteria, nineteen Pseudomonas aeruginosa, eight Serratia marcescens, four Moraxella spp., two Haemophilus spp., and ten other Gram-negative bacteria isolates were tested. MICs of doxycycline were compared to a serum standard concentration of doxycycline (SSCD) of 4 µg/mL and concentrations that would be found in 50% and 20% serum component clinical preparations of ASD, corresponding to 50% SSCD (2 µg/mL) and 20% SSCD (0.8 µg/mL), respectively. MICs equal to or less than these values were used to deem a bacterial isolate susceptible.

RESULTS

For Gram-positive bacteria, susceptibilities to SSCD, 50% SSCD, and 20% SSCD were 86%, 65%, and 60%, respectively. For Gram-negative bacteria, susceptibilities to SSCD, 50% SSCD, and 20% SSCD were 37.2%, 23.3%, and 11.6%, respectively. Chi-squared analyses comparing Gram-positive and Gram-negative susceptibilities showed significantly greater susceptibility of Gram-positive bacteria at all three tested MICs (<0.0001, <0.0001, <0.0001).

CONCLUSIONS

Our data suggest that autologous serum drops containing theoretic concentrations of doxycycline may provide an additional anti-bacterial effect in the treatment of bacterial keratitis, especially for Gram-positive bacterial keratitis compared to Gram-negative bacterial keratitis.

[Treatment of ocular mucous membrane pemphigoid]

Ocular mucous membrane pemphigoid is the manifestation of a systemic autoimmune disease. As autoantibodies circulating in the blood cannot be adequately treated by eye drops, systemic immunosuppressive treatment of this autoimmune disease naturally plays the most important role. Ophthalmic topical or even surgical procedures are only used as supportive measures or usually to control ocular complications that have developed. Patients with the typical clinical picture are treated causally with systemic immunosuppression causally, nurturing eye drops, as well as by minimally invasive surgery if complications arise, if possible in an inflammation-free state, in accordance with the guidelines if the diagnosis is positive but also if the biopsy and serology are repeatedly negative after exclusion of all differential diagnoses. Purely topical anti-inflammatory treatment is insufficient to prevent irreversible progression of scarring conjunctivitis. Corresponding treatment recommendations have been formulated in current European as well as German guidelines and are presented here as an overview.

Anti-Inflammatories in the Treatment of Dry Eye Disease: A Review

Inflammation is an important driver of dry eye disease (DED) pathogenesis. An initial insult that results in the loss of tear film homeostasis can initiate a nonspecific innate immune response that leads to a chronic and self-sustaining inflammation of the ocular surface, which results in classic symptoms of dry eye. This initial response is followed by a more prolonged adaptive immune response, which can perpetuate and aggravate inflammation and result in a vicious cycle of chronic inflammatory DED. Effective anti-inflammatory therapies can help patients exit this cycle, and effective diagnosis of inflammatory DED and selection of the most appropriate treatment are therefore key to successful DED management and treatment. This review explores the cellular and molecular mechanisms of the immune and inflammatory components of DED, and examines the evidence base for the use of currently available topical treatment options. These agents include topical steroid therapy, calcineurin inhibitors, T cell integrin antagonists, antibiotics, autologous serum/plasma therapy, and omega-3 fatty acid dietary supplements.

Eye drops of human origin-Current status and future needs: Report on the workshop organized by the ISBT Working Party for Cellular Therapies

BACKGROUND AND OBJECTIVES

Serum eye drops (SEDs) are used to treat ocular surface disease (OSD) and to promote ocular surface renewal. However, their use and production are not standardized, and several new forms of human eye drops have been developed.

MATERIALS AND METHODS

The International Society for Blood Transfusion Working Party (ISBT WP) for Cellular Therapies held a workshop to review the current types of eye drops of human origin (EDHO) status and provide guidance.

RESULTS

The ISBT WP for Cellular Therapies introduced the new terminology 'EDHO' to emphasize that these products are analogous to 'medical products of human origin'. This concept encompasses their source (serum, platelet lysate, and cord blood) and the increasingly diverse spectrum of clinical usage in ophthalmology and the need for traceability. The workshop identified the wide variability in EDHO manufacturing, lack of harmonized quality and production standards, distribution issues, reimbursement schemes and regulations. EDHO use and efficacy is established for the treatment of OSD, especially for those refractory to conventional treatments.

CONCLUSION

Production and distribution of single-donor donations are cumbersome and complex. The workshop participants agreed that allogeneic EDHO have advantages over autologous EDHO although more data on clinical efficacy and safety are needed. Allogeneic EDHOs enable more efficient production and, when pooled, can provide enhanced standardization for clinical consistency, provided optimal margin of virus safety is ensured. Newer products, including platelet-lysate- and cord-blood-derived EDHO, show promise and benefits over SED, but their safety and efficacy are yet to be fully established. This workshop highlighted the need for harmonization of EDHO standards and guidelines.

Platelets, Protean Cells with All-Around Functions and Multifaceted Pharmacological Applications

Platelets, traditionally known for their roles in hemostasis and coagulation, are the most prevalent blood component after erythrocytes (150,000-400,000 platelets/μL in healthy humans). However, only 10,000 platelets/μL are needed for vessel wall repair and wound healing. Increased knowledge of the platelet's role in hemostasis has led to many advances in understanding that they are crucial mediators in many other physiological processes, such as innate and adaptive immunity. Due to their multiple functions, platelet dysfunction is involved not only in thrombosis, mediating myocardial infarction, stroke, and venous thromboembolism, but also in several other disorders, such as tumors, autoimmune diseases, and neurodegenerative diseases. On the other hand, thanks to their multiple functions, nowadays platelets are therapeutic targets in different pathologies, in addition to atherothrombotic diseases; they can be used as an innovative drug delivery system, and their derivatives, such as platelet lysates and platelet extracellular vesicles (pEVs), can be useful in regenerative medicine and many other fields. The protean role of platelets, from the name of Proteus, a Greek mythological divinity who could take on different shapes or aspects, is precisely the focus of this review.

Marginal Corneal Infiltration Following Treatment for Metastatic Breast Cancer with Triple Chemotherapy of Trastuzumab, Pertuzumab & Docetaxel

PURPOSE

To report a case of bilateral marginal corneal infiltration upon treatment with trastuzumab, pertuzumab, and docetaxel via novel proposed mechanisms.

CASE DESCRIPTION

A patient, diagnosed with metastatic breast cancer and positive for human epidermal growth factor receptor 2 (HER2) with high Ki67, presented with bilateral severe marginal corneal infiltration upon undergoing first cycle of triple chemotherapy: trastuzumab, pertuzumab, and docetaxel. Treatment with topical corticosteroids and antibiotics was unsuccessful and was replaced by allogeneic serum eye drops (SED). The case improved significantly 10 days upon starting allogeneic SED.

CONCLUSIONS

We propose that trastuzumab, pertuzumab, and docetaxel suppress HER2 and Ki67 in the cornea and lacrimal gland. To the best of our knowledge, our report is the first to highlight the potential impact of this triple chemotherapy on the lacrimal gland and cornea and the first to highlight the proposed role of Ki67 suppression in damaging corneal integrity.

[Corneal regeneration: is there a place for tissues of perinatal origin?]

The article reviews the main properties of the cornea and the mechanisms of its physiological regeneration and repair in response to damage and describes the most promising methods of treatment aimed at stimulating limbal stem cells and based on the use of native tissues of perinatal origin, umbilical cord mesenchymal stromal cells, and cell-free therapeutic products.

A Novel Ferroptosis Inhibitor UAMC-3203, a Potential Treatment for Corneal Epithelial Wound

Corneal wound, associated with pain, impaired vision, and even blindness, is the most common ocular injury. In this study, we investigated the effect of a novel ferroptosis inhibitor, UAMC-3203 (10 nM-50 µM), in corneal epithelial wound healing in vitro in human corneal epithelial (HCE) cells and ex vivo using alkali-induced corneal wounded mice eye model. We evaluated in vivo acute tolerability of the compound by visual inspection, optical coherence tomography (OCT), and stereomicroscope imaging in rats after its application (100 µM drug solution in phosphate buffer pH 7.4) twice a day for 5 days. In addition, we studied the partitioning of UAMC-3203 in corneal epithelium and corneal stroma using excised porcine cornea. Our study demonstrated that UAMC-3203 had a positive corneal epithelial wound healing effect at the optimal concentration of 10 nM (IC₅₀ value for ferroptosis) in vitro and at 10 µM in the ex vivo study. UAMC-3203 solution (100 µM) was well tolerated after topical administration with no signs of toxicity and inflammation in rats. Ex-vivo distribution study revealed significantly higher concentration (~12-38-fold) and partition coefficient (K_p) (~52 times) in corneal epithelium than corneal stroma. The UAMC-3203 solution (100 µM) was stable for up to 30 days at 4 °C, 37 °C, and room temperature. Overall, UAMC-3203 provides a new prospect for safe and effective therapy for corneal wounds.

Age-Related Differences in the Clinical Patterns of Ocular Graft-Versus-Host Disease

Objectives

To evaluate age-related differences in clinical patterns of ocular graft-versus-host disease (GVHD).

Materials and Methods

In this cross-sectional study, patients diagnosed with ocular GVHD were evaluated in two groups: Group I included those aged 18 years or younger and Group II included those over 18 years of age. Demographic and clinical information were recorded and compared between the groups.

Results

Forty eyes of 20 patients were included (11 patients were in Group I and 9 patients were in Group II). Follow-up was at least 6 months. All patients had burning, dryness, and foreign body sensation. Conjunctival hyperemia, cicatricial conjunctivitis, and limbal stem cell disease (LSCD) was observed more frequently in Group II. In addition to non-preserved artificial tears, cyclosporine A 0.05% (65%) and autologous/allogeneic serum eye drops (80%) were given and silicone plugs were inserted (28%). In Group I, an improvement in GVHD scoring and best corrected visual acuity was observed after 6 months of treatment (p<0.0005).

Conclusion

In ocular GVHD, conjunctival cicatrization and limbal stem cell deficiency might be observed more often in adults. Topical cyclosporine, autologous/allogenic serum drops, and punctal plugs are helpful in moderate or more severe cases. With early diagnosis and treatment, an improvement in clinical signs and visual acuity might be observed, particularly in younger patients.

Novel drug delivery systems for the management of dry eye

Dry eye disease (DED) is a frequently observed eye complaint, which has recently attracted considerable research interest. Conventional therapy for DED involves the use of artificial tear products, cyclosporin, corticosteroids, mucin secretagogues, antibiotics and nonsteroidal anti-inflammatory drugs. In addition, ocular drug delivery systems based on nanotechnology are currently the focus of significant research effort and several nanotherapeutics, such as nanoemulsions, nanosuspensions, microemulsions, liposomes and nanomicelles, are in clinical trials and some have FDA approval as novel treatments for DED. Thus, there has been remarkable progress in the design of nanotechnology-based approaches to overcome the limitations of ophthalmic formulations for the management of anterior eye diseases. This review presents research results on diagnostic methods for DED, current treatment options, and promising pharmaceuticals as future therapeutics, as well as new ocular drug delivery systems.

Synthetic Heparan Sulfate Mimetic Polymer Enhances Corneal Nerve Regeneration and Wound Healing after Experimental Laser Ablation Injury in Mice

(1) Background: Abnormal corneal wound healing compromises visual acuity and can lead to neuropathic pain. Conventional treatments usually fail to restore the injured corneal tissue. In this study, we evaluated the effectiveness of a synthetic heparan sulfate mimetic polymer (HSmP) in a mouse model of corneal wound healing. (2) Methods: A surgical laser ablation affecting the central cornea and subbasal nerve plexus of mice was used as a model of the wound-healing assay. Topical treatment with HSmP was contrasted to its vehicle and a negative control (BSS). Corneal repair was studied using immunofluorescence to cell proliferation (Ki67), apoptosis (TUNEL assay), myofibroblast transformation (αSMA), assembly of epithelial cells (E-cadherin) and nerve regeneration (β-tubulin III). (3) Results: At the end of the treatment, normal epithelial cytoarchitecture and corneal thickness were achieved in HSmP-treated animals. HSmP treatment reduced myofibroblast occurrence compared to eyes irrigated with vehicle (p < 0.01) or BSS (p < 0.001). The HSmP group showed 50% more intraepithelial nerves than the BSS or vehicle groups. Only HSmP-treated corneas improved the visual quality to near transparent. (4) Conclusions: These results suggest that HSmP facilitates the regeneration of the corneal epithelium and innervation, as well as restoring transparency and reducing myofibroblast scarring after laser experimental injury.

Ocular surface optimization before cataract surgery

The evolution of refractive cataract surgery has increased patient expectations for visual outcomes following cataract surgery. Precise biometry and keratometry are critical for accurate intraocular lens (IOL) selection and favorable surgical outcomes. In patients with the ocular surface disease and corneal pathologies, preoperative measurements can often be erroneous, leading to postoperative refractive surprises and dissatisfied patients. Conditions such as dry eye disease, epithelial basement membrane dystrophy, Salzmann's nodular dystrophy, and pterygia need to be addressed thoroughly before performing cataract surgery to optimize the ocular surface, obtain high-quality preoperative measurements, and ultimately determine the appropriate IOLs. In this review, the various ocular surface pathologies affecting cataract surgery outcomes and options for treatment are discussed and the importance of optimization of the ocular surface before cataract surgery is reviewed.

Dry eye syndrome: comprehensive etiologies and recent clinical trials

Dry eye syndrome (DES) is multifactorial and likely to be a cause of concern more so than ever given the rapid pace of modernization, which is directly associated with many of the extrinsic causative factors. Additionally, recent studies have also postulated novel etiologies that may provide the basis for alternative treatment methods clinically. Such insights are especially important given that current approaches to tackle DES remains suboptimal. This review will primarily cover a comprehensive list of causes that lead to DES, summarize all the upcoming and ongoing clinical trials that focuses on treating this disease as well as discuss future potential treatments that can improve inclusivity.

Refolding of bioactive human epidermal growth factor from E. coli BL21(DE3) inclusion bodies & evaluations on its in vitro & in vivo bioactivity

Human epidermal growth factor (hEGF) is a mitogenic protein widely used in pharmaceutical and cosmetic industries, thus recombinant DNA technology has been applied to meet the high demand for hEGF. The overexpression of recombinant protein in E. coli often leads to the formation of inclusion bodies (IBs). Mild solubilisation preserves the native secondary protein structure in IBs, thereby the high recovery of active protein from IBs. The redox system also plays a pivotal role in the formation of disulphide bonds during refolding of disulphide bond-containing protein. This study aimed to recover hEGF from bacterial IBs through freeze-thawing solubilisation and glutathione-based oxidative refolding. CBD-Ssp DnaB-hEGF fusion protein was expressed as IBs in E. coli, washed with Triton X-100 and urea to remove most protein contaminants, then the solubilised fusion protein was obtained by freeze-thawing with the addition of 2 M urea. The solubilised protein was subsequently refolded by intein cleavage via a glutathione-based redox system. The refolded hEGF demonstrated heat-resistant properties, interacted with specific antibodies on ELISA, stimulated keratinocyte proliferation and possessed significant in vivo wound healing properties on the 8th day, confirming that hEGF was correctly folded. In summary, the protocol described is suitable for the recovery of refolded hEGF from bacterial IBs by mild solubilisation and oxidative refolding.

Equine Umbilical Cord Serum Composition and Its Healing Effects in Equine Corneal Ulceration

Background

Human autologous serum (AS) and umbilical cord serum (UCS) both contain growth and neurotrophic factors that promote corneal healing.

Aim

Our objectives were to compare equine AS and UCS cytokine and growth factor profiles and to assess the safety and clinical feasibility of the therapeutic use of UCS eye drops in cases of spontaneous complex ulcers.

Study Design

Prospective clinical trial.

Methods

Vitamin A insulin growth factor, platelet-derived growth factor-BB, transforming growth factor (TGF)-β1 (enzyme-linked immunosorbent assay), interleukin (IL)-1β, IL-6, interferon-γ, and monocyte chemoattractant protein 1 concentrations were determined in 10 AS collected from different horses and 10 UCS sampled at delivery. Six client-owned horses presenting with complex non-healing corneal defects of >5 mm² were included in a clinical trial and treated with conventional therapy and conditioned UCS drops for 8–15 days. Ulcer surface and time to complete epithelialization were recorded.

Results

Median concentrations of vitamin A, insulin growth factor, and platelet-derived growth factor-BB were not significantly different in AS compared with UCS (respectively, 14.5 vs. 12.05 μg/ml; 107.8 vs. 107.3 pg/ml; and 369.1 vs. 924.2 pg/ml). TGF-β1 median concentration in UCS was significantly higher than in AS (3,245 vs. 2571pg/ml) (p = 0.04). IL-1β, IL-6, interferon-γ, and monocyte chemoattractant protein 1 concentrations were variable in AS and undetectable in UCS. The corneal median ulcerative area was 37.2 mm² (6.28–57.14 mm²) and had a duration of 4–186 days (median 19 days). All lesions healed within 13–42 days (median 17 days). No adverse effects nor recurrences within 1 month were noticed.

Limitations

The sample size was small. Spontaneous corneal epithelial defects presented with variable clinical characteristics. There were no age-matched control horses to assess corneal healing time and rate.

Conclusion and Clinical Significance

Equine UCS may be beneficial, as it contains no pro-inflammatory cytokines and a greater concentration of TGF-β1 compared with AS. Topical UCS appears safe and may potentially be used as adjunctive therapy for equine complex non-healing ulcers.

Autologous versus allogeneic versus umbilical cord sera for the treatment of severe dry eye disease: a double-blind randomized clinical trial

PURPOSE

To measure the effects of Autologous serum (AS), Allogeneic Serum (HS) and Umbilical Cord serum (CS) eye drops in severe dry eye disease (DES), as well as to characterize and quantify several molecules in the three sera (albumin, fibronectin; Vitamin A and E; IgG, IgA and IgM; Transforming growth factor β; Epithelial growth factor).

METHODS

Randomized, double-blind, single-centre, three-arm (AS, HS and CS) clinical trial. Sixty-three subjects were included with severe DES, 21 in each arm of the study. Visual acuity, Schirmer test, Breakup time (BUT), lissamine green, fluorescein staining measurements and a questionnaire were performed prior to treatment, and after one-month and three-month follow-up.

RESULTS

There was a significant main effect of time on visual acuities, Schirmer and BUT tests and fluorescein and lissamine green staining measurements and questionnaire scores (p = 0.015, p = 0.002, p < 0.001, p < 0.001, p = 0.031 and p < 0.001, respectively), although there was no significant interaction between time and serum type, nor between serum type and the test performed. Regarding the concentration of molecules, in our study AS contained significantly higher concentrations of IgA, IgG and fibronectin whereas HS contained significantly higher concentration of IgM, vitamins A and E, TGF and albumin. Contrary to previous reports, CS did not show higher concentration of any of the molecules analysed.

CONCLUSIONS AND RELEVANCE

The three sera were effective in the treatment of severe DES. CS did not contain a higher proportion of molecules compared to AS/HS. More research is needed to assess the effect of AS in patients with DES and autoimmune diseases.

Effect of Autologous Serum Eye Drops on Corneal Haze after Corneal Cross-linking

SIGNIFICANCE

Corneal haze remains a frequent post-operative finding in patients undergoing corneal cross-linking. It has been shown that autologous serum tears promote epithelial healing and reduce post-operative pain; however, the role in the prevention of corneal haze has not been reported.

PURPOSE

This study aimed to compare the effect of autologous serum tears versus preservative-free artificial tears on the prevention and resolution of post-cross-linking corneal haze.

METHODS

A retrospective cohort study was conducted in a sample population from one surgeon at a tertiary eye center from 2016 to 2019. Seventy-six eyes of consecutive patients who underwent cross-linking were included. Records were reviewed for corneal Scheimpflug densitometry values and maximum keratometry, epithelial healing time, and the use of either autologous serum tears or preservative-free artificial tears. Corneal densitometry values, expressed in standardized grayscale units (GSU), were recorded for the anterior 150-μm corneal stroma and in the 0.0 to 2.0 mm and 2.0 to 6.0 mm zones.

RESULTS

Forty-four eyes received autologous serum tears, whereas 32 eyes received preservative-free artificial tears. The baseline GSU of the anterior stromal 0 to 2 mm annulus and the 2 to 6 mm annulus did not significantly differ between groups (P = .50 and P = .40, respectively). There was a statistically significant increase in mean GSU for both anterior 0 to 2 mm and 2 to 6 mm zones between baseline and 1 month (P < .001) and 3 months (P < .001). When comparing the two groups, no statistically significant difference was found post-operatively between the mean GSU at 1 month for the anterior 0 to 2 mm (P = .38) nor the 2 to 6 mm zone (P = .12), or for the third month (P = .60 and P = .44, respectively).

CONCLUSIONS

Using Scheimpflug densitometry, we did not find a significant difference in the post-cross-linking corneal haze at 1 and 3 post-operative months between patients who use autologous serum tears and those who use preservative-free artificial tears.

Incidence, prevalence, and outcome of moderate to severe neurotrophic keratopathy in a German tertiary referral center from 2013 to 2017

Background

Neurotrophic keratopathy (NK) is an orphan disease, with an estimated prevalence of 1–5/10,000. No data regarding the incidence exists. The primary aim was to evaluate incidence and prevalence of NK at a tertiary referral center in Germany, and the secondary aim was to analyze demographic parameters, etiology, and clinical features and therapeutic outcomes.

Methods and material

All patients treated for NK with serum eye drops (SED), amnionic membrane transplantation (AMT), or penetrating keratoplasty (PK) in 2013–2017 were identified. Age, sex, etiology of NK, visual acuity, disease stage, treatment, and visual acuity were analyzed. Incidence and prevalence of NK in our hospital and the overall population of the city were calculated.

Results

In 63 eyes of 60 patients (56.7% male; 68 ± 16 years), the most common underlying diseases were herpetic infections (23.8%), neurological causes (19%), and diabetes mellitus (14.3%). The annual incidence of NK in our tertiary referral center ranges between 5/10,000 and 3/10,000, the prevalence between 9/10,00 and 22/10,000. In all patients treated with corneal ulcers, the prevalence was up to 27% (2706/10,000). The incidence in the overall population is estimated at 0.1–0.3/10,000, the prevalence at 0.2–0.5/10,000 to 0.5/10,000.

Conclusion

Based on our assessment, the prevalence of NK in the overall population is lower than estimated before. However, in patients with corneal ulcers, the percentage of NK is comparably high. The disease may still be underdiagnosed due to the variety of underlying disorders and unknown comorbidities. Thus, in cases of therapy-refractive superficial keratopathy or ulcerations, NK should be considered more frequently.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00417-021-05535-z.

Improving morphological outcome in lamellar macular hole surgery by using highly concentrated autologous platelet-rich plasma

Purpose

To evaluate the use of highly concentrated autologous platelet-rich plasma (PRP) in lamellar macular hole (LMH) surgery with regard to function and morphology.

Methods

We included 12 eyes of 12 patients with progressive LMH in this interventional case series. After 23/25-gauge pars plana vitrectomy, 0.1ml highly concentrated autologous platelet-rich plasma was applied under air tamponade. Induction of posterior vitreous detachment and peeling of tractive epiretinal membranes were performed whenever present. Phacovitrectomy was undertaken in cases of phakic lens status. Postoperatively, all patients were instructed to rest in a supine position for the first two postoperative hours. Best-corrected visual acuity (BCVA) testing, microperimetry, spectral-domain optical coherence tomography (SD-OCT), and fundus photography were carried out preoperatively and 6 months postoperatively.

Results

Foveal configuration was restored in 10 of 12 patients (83.3%) at 6 months postoperatively. Two patients who had not undergone ILM peeling showed a recurring defect at 6-month follow-up. Best-corrected visual acuity improved significantly from 0.29 ± 0.08 to 0.14 ± 0.13 logMAR (Wilcoxon: p=0.028). Microperimetry remained unchanged (23.38 ± 2.53 preoperatively; 23.0 ± 2.49 dB postoperatively; p=0.67). No patient experienced vision loss after surgery, and no significant intra- or postoperative complications occurred.

Conclusion

The application of PRP in the surgical therapy of LMH results in good morphological and functional outcomes. Additional peeling of the ILM seems to be mandatory when using PRP to prevent the recurrence of LMH. Strict postoperative supine positioning for 2 h avoids PRP dislocation. Larger sample sizes are needed to confirm the results.

Proteomic Characterization of Plasma Rich in Growth Factors and Undiluted Autologous Serum

Over the last three decades, there has been special interest in developing drugs that mimic the characteristics of natural tears for use it in the treatment of several ocular surface disorders. Interestingly, the composition of blood plasma is very similar to tears. Therefore, different blood-derived products like autologous serum (AS) and plasma rich in growth factors (PRGF) have been developed for the treatment of diverse ocular pathologies. However, scarce studies have been carried out to analyze the differences between both types of blood-derived products. In the present study, blood from three healthy donors was drawn and processed to obtain AS and PRGF eye drops. Then, human corneal stromal keratocytes (HK) were treated with PRGF or undiluted AS. Proteomic analysis was carried out to analyze and characterize the differential protein profiles between PRGF and AS, and the differentially expressed proteins in HK cells after PRGF and AS treatment. The results obtained in the present study show that undiluted AS induces the activation of different pathways related to an inflammatory, angiogenic, oxidative stress and scarring response in HK cells regarding PRGF. These results suggest that PRGF could be a better alternative than AS for the treatment of ocular surface disorders.

Combinatorial therapy with immunosuppressive, immunomodulatory and tear substitute eyedrops ("Triple Play") in Recalcitrant Immunological Ocular Surface Diseases

PURPOSE

The current paradigm for therapy of recalcitrant ocular surface diseases (OSD) consists of a sequential, step-up treatment approach. A combinatorial topical therapy (anti-inflammatory/immunosuppressive [steroid] with immunomodulatory [pooled human immune globulin] and tear substitute [serum]) that simultaneously targets several immunological pathways may be more efficacious. This report evaluates if the combinatorial therapy resulted in clinical benefit in patients with recalcitrant OSD.

METHODS

We performed a retrospective case study of patients receiving topical, preservative-free, compounded formulations of steroids, pooled human immune globulin, and serum tears. Outcome measures included visual acuity, ocular surface disease index (OSDI), ocular discomfort score, subjective global assessment (SGA), corneal staining, conjunctival redness, and slit lamp photographs.

RESULTS

Patients consisted of one male and 11 females ranging in age from 27 to 87 years old. Pathologies included ocular graft-versus-host disease (n = 4), Sjögren's syndrome (n = 3), ocular cicatricial pemphigoid (n = 1), pemphigus vulgaris (n = 1), peripheral ulcerative keratitis (n = 1), Stevens-Johnson syndrome (n = 1), and giant papillary conjunctivitis (n = 1). All patients were "improved" or "much improved" on SGA after combinatorial therapy. There was a clinically meaningful reduction in OSDI, ocular discomfort, corneal staining, and conjunctival injection. Additionally, three patients had improvement in their visual acuity (one from 20/400 to 20/20). Adverse effects included increased intraocular pressure in two patients, presumably due to topical steroid use.

CONCLUSIONS

Combinatorial therapy provides clinical benefit by reducing the symptoms and signs in recalcitrant OSD. Our study provides the rationale for performing prospective clinical trials to evaluate the efficacy of combinatorial therapy for treating recalcitrant OSD.

Aniridia and the ocular surface: Medical and surgical problems and solutions

Congenital aniridia is a multisystemic genetic disease due to a mutation in PAX6 gene which severely affects the development and functionality of the human eyes. In patients affected by the mutation, aside from the absence or defects of iris tissue formation, abnormalities in position or opacities of the crystalline lens, macular hypoplasia, ocular surface disease is the main cause of visual loss and the deterioration of the quality of life of most patients. Limbal stem cell deficiency combined with tear film instability and secondary dry eye cause aniridic keratopathy which, in advanced stages, ends up in corneal opacification. In this paper, the actual knowledge about congenital aniridia keratopathy physiopathology and medical and surgical treatment options and their efficacy are discussed. Indications and results of topical treatments with artificial tears and blood-derivatives in its initial stages, and different surgical techniques as limbal stem cell transplantation, keratoplasty and keratoprostheses are reviewed. Finally, recent advances and results in regenerative medicine techniques with ex vivo stem cell cultivation or other types of cultivated cells are presented.

Autologous serum eye drops for ocular surface disorders

PURPOSE OF REVIEW

Ocular surface disease is a prevalent, diverse group of conditions that cause patient discomfort and decreased visual acuity and present considerable expense to both patients and healthcare systems. Autologous serum eye drops are a topical treatment modality derived from the patient's own blood. Use of serum eye drops for ocular surface disease has been promising due to biochemical similarities to endogenous tears.

RECENT FINDINGS

Use of serum eye drops for moderate to severe ocular surface diseases such as dry eye, corneal epithelial defects, and inflammatory conditions has become more prevalent. Recent studies have demonstrated that the use of serum eye drops is well-tolerated by patients and associated with improvement in patient-reported outcomes and objective dry eye parameters. Production of serum eye drops may vary, treatment costs can be significant, and the quality of evidence for serum eye drop use published from randomized controlled trials is modest, particularly for long-term treatment. Accessibility remains an area for improvement and may be complemented by allogeneic serum eye drops.

SUMMARY

Serum eye drops are frequently used as a safe, well-tolerated, and effective treatment for ocular surface disease. Further research is needed to assess long-term outcomes and improve accessibility.

Treatment of persistent epithelial defects with single-dose autologous serum eye drops

PURPOSE

We aimed to investigate the efficacy and safety of single-dose autologous serum eye drops (ASEDs) for treatment of persistent corneal epithelial defects (PEDs).

METHODS

About 34 eyes of 26 patients treated from March 2016 to May 2020 with a single dose of ASEDs for PEDs that did not respond to conventional treatment were retrospectively evaluated. Patient demographics, predisposing factors, size, and duration of the PED, duration of treatment, and dosage of ASEDs, PED healing time, success rate of the ASED treatment, and follow-up time after the onset of ASED treatment were recorded. Autologous serum eye drops (20%) were prepared by diluting the serum with preservative-free artificial tears in single-dose vials. Vials were stored at -20°C and used daily after dissolving.

RESULTS

The mean patient age was 47.0 ± 18.5 years, and 13 (50%) of the patients were male. The most common indication for ASEDs was PED after keratoplasty. The mean duration of ASED treatment was 8.5 ± 6.3 months, and mean follow-up time was 22.8 ± 12.2 months. Autologous serum eye drop treatment was effective in 25 (73.5%) eyes and partially effective in 5 (14.7%) eyes. None of the eyes displayed complications related to the treatment.

CONCLUSION

In patients with PED for whom conservative treatment is insufficient, ASEDs prepared by dilution with preservative-free artificial tears in single-dose vials and administered based on the daily use principle appear to be effective and safe.

Amniotic membrane extract eye drops: a new approach to severe ocular surface pathologies

A protocol for processing amniotic membrane as an extract to be re-hydrated and administered topically as eye drops (amniotic membrane extract eye drops, AMEED) has been developed. Safety and efficacy of AMEED was assessed in patients with severe ocular surface pathologies. prospective clinical follow-up of ocular surface symptoms before and after regular application of the AMEED for at least 4 weeks on patients with severe ocular surface disorders as chronic dry eye disease, limbal stem cell deficiency, neurotrophic ulcer and permanent and disabling symptomatology that were refractory to conventional treatment. Efficacy and tolerability were assessed based on patient-reported symptoms, objective measurements, and reports of adverse events. Thirty-six eyes from 25 patients were included. Although the visual quality function score, by means of a VQF25 questionnaire, was not statistically different after the treatment (p = 0.4657), there was a clear trend, statistically significant, towards the improvement in ocular symptoms like foreign body sensation, itching and stinging (p < 0.05) and clinical presentation of the pathology. All patients with corneal ulcer showed complete epithelization. Topically applied AMEED proved to be safe, well tolerated and effective in reducing the symptoms and clinical signs of severe ocular disease. Further studies are needed to confirm the best indications for AMEED use.

Short- and Long-Term Stability of Plasma Rich in Growth Factors Eye Drops

PURPOSE

To analyze whether plasma rich in growth factors (PRGFs) eye drops preserve their activity and biological properties after storage for 9 and 12 months at -20°C, and at 4°C, and at room temperature (RT) for 3 and 7 days in comparison to fresh samples (t0).

METHODS

PRGF eye drops were obtained from 6 healthy donors. Then, they were stored for 9 and 12 months at -20°C. At each time, different PRGF eye drops samples were thawed and maintained at RT or at 4°C for 3 and 7 days. Platelet-derived growth factor-AB, epidermal growth factor, transforming growth factor-β1, vascular endothelial growth factor, angiopoietin-1, and thrombospondin-1 were analyzed at each time and temperature of storage. In addition, the pH level, the microbial contamination, and the proliferative potential on primary human corneal stromal fibroblasts human keratocytes of each obtained PRGF eye drops were also evaluated.

RESULTS

All growth factor levels were preserved at each time and storage condition. No differences were observed on the human keratocytes proliferation after treatment with PRGF eye drops at any studied time or temperature. No microbial contamination was observed in any of the PRGF eye drops. Finally, the pH levels increased significantly after 9 and 12 months of storage at -20°C compared with t0.

CONCLUSIONS

PRGF eye drops can be stored for up to 12 months without reduction of the main growth factors and proteins and without any microbial contamination. Furthermore, the biological activity of the PRGF eye drops is maintained after storing for 3 and 7 days at 4°C or at RT.

Progress in the use of plasma rich in growth factors in ophthalmology: from ocular surface to ocular fundus

Introduction: The use of blood derivatives and especially Plasma rich in growth factors (PRGF), for regenerative purposes has been a common trend along the last decades in the field of oral surgery, dermatology, orthopedics, and more recently in ophthalmology.Areas covered: PRGF is a type of platelet-rich plasma that is being explored for the treatment of ocular injuries. The present review article highlights 50 ophthalmology-related publications about the application of PRGF in the treatment of acute and chronic pathologies in ophthalmology as well as most relevant challenges and future prospects.Expert opinion: PRGF technology provides a wide range of formulations that can be used therapeutically in many different acute and chronic ocular pathologies. In addition to eye drops enriched with autologous growth factors, PRGF enables the preparation of both immunologically safe and fibrin-based formulations. Recent advances in the field have promoted PRGF storage for 12 months under freezing conditions, its daily use for 7 days at room temperature and the freeze-dried formulation. The thermally treated immunosafe formulation has shown promising clinical results for the treatment of several diseases such as Sjögren syndrome, graft versus host disease or cicatrizing conjunctivitis. In addition, several fibrin formulations have been preclinically evaluated and clinically incorporated as an adjuvant to ocular surface or glaucoma surgeries, dermal fat graft procedures, limbal stem cell expansion and retinal surgeries. The present review explores the latest scientific and clinical data, current challenges, and main prospects of this technology for the treatment of several ocular injuries.

The Lucerne Protocol for the Production of Autologous Serum Eyedrops

BACKGROUND

There are a variety of protocols for manufacturing autologous serum (AS) eye drops. The Lucerne protocol for the production of AS eye drops uses a slightly reduced gravitational (g)-force and time for the centrifugation process (2500 × g for 10 minutes), compared to previously published optimised protocols, to obtain high levels of epitheliotropic growth factors (3000 × g for 15 minutes). The goal of this study was to compare the concentrations of growth factors, albumin and lysozyme in autologous serum eye drops manufactured with these protocols.

MATERIAL AND METHODS

Blood from 5 healthy volunteers was placed in plastic tubes without an anticoagulant. Tubes from each donor were left in a vertical position for 2 hours at room temperature to facilitate coagulation, followed by centrifugation at either 2500 × g for 10 minutes or at 3000 × g for 15 minutes at room temperature. The serum levels of beta nerve growth factor (β-NGF), transforming growth factor β1 (TGF-β1), epidermal growth factor (EGF), hepatocyte growth factor (HGF), platelet-derived growth factor BB (PDGF-BB) and vascular endothelial growth factor A (VEGF-A) were measured in triplicate with a multi-analyte Simple Plex platform. The Simple Plex cartridge allows each sample to be run in triplicate for each analyte and prevents any interaction between the antibody components for each biomarker. The serum level of albumin was measured by turbidimetric immunoassay Tina-quant and of lysozyme by single radial immunodiffusion assay.

RESULTS

For all analytes, the reduced g-force and centrifugation time did not result in a significant difference in serum levels.

CONCLUSIONS

The Lucerne protocol for the production of autologous serum eye drops with reduced g-force and a shorter centrifugation time does not affect the concentrations of the main epitheliotropic growth factors, albumin and lysozyme, in AS eye drops.