Human Serum Eye Drops in Eye Alterations: An Insight and a Critical Analysis

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.

Nano-composite system of traditional Chinese medicine for ocular applications: molecular docking and three-dimensional modeling insight for intelligent drug evaluation

The absorption of drugs was impeded in the posterior part of the eye due to the special structure. In addition, it was crucial to comprehend transport laws of molecules in ocular drug delivery for designing effective strategies. However, the current quality evaluation methods of the eye were backward and lack of dynamic monitoring of drug processes in vivo. Herein, nano-drug delivery system and three-dimensional (3D) model were combined to overcome the problems of low bioavailability and diffusion law. The model drugs were screened by molecular docking. The flexible nano-liposome (FNL) and temperature-sensitive gel (TSG) composite formulation was characterized through comprehensive evaluation. COMSOL software was utilized to build 3D eyeball to predict the bioavailability of drugs. The size of the preparation was about 98.34 nm which is relatively optimal for the enhanced permeability of the eyes. The formulation showed a stronger safety and non-irritant. The pharmacokinetics results of aqueous humor showed that the AUC of two drugs in this system increased by 3.79 and 3.94 times, respectively. The results of 3D calculation model proved that the concentrations of drugs reaching the retina were 1.90×10-5 mol/m3 and 6.37×10-6 mol/m3. In conclusion, the FNL-TSG markedly improved the bioavailability of multiple components in the eye. More importantly, a simplified 3D model was developed to preliminarily forecast the bioavailability of the retina after drug infusion, providing technical support for the accurate evaluation of ocular drug delivery. It provided new pattern for the development of intelligent versatile ophthalmic preparations.

MIC-1 Antlerogenic Stem Cells Homogenate from Cervus elaphus Accelerate Corneal Burn Reepithelization in Rabbits

Deer antler is the only mammalian organ that can fully grow back once lost from its pedicle. Antler regeneration is a stem cell-based process. Therefore, antlers probably offer the most pertinent model for studying organ regeneration in mammals. Evaluation of the effect of deer antler stem cells on the healing of superficial and deep rabbit corneal wounds was performed. Thirty-six New Zealeand White rabbits were used in this study in superficial and deep denaturation models, and corneal erosion was performed with n-heptanol placed on the cornea for 30 and NaOH for 90 s. Antler stem cells in drop formulation with hyaluronate was used. As a control, sodium hyaluronate in the superficial model and protein-free calf blood dialysate (Solcoseryl) in the deep model were administered. In superficial corneal damage, a reduction in the area of the damaged cornea was observed from day 3 of the experiment to an adequate level: 45% in the test group and 52% in the control group relative to the baseline damage (100%). Between days 3 and 7, on average, a smaller lesion area was observed in the group receiving antler stem cells. The use of antler stem cells has resulted in a marked improvement in cornea clarity. According to the 5-point scale of corneal opacity evaluation, where 1 is completely clear and 5 is completely opaque, the first statistically significant changes were observed after 4 weeks of treatment: 3.0 in the study group, 4.1 in the control with Solcoseryl, and 4.4 in the control group. After 9 weeks, these values were, 2.5, 3.8, and 4.1, respectively. The present preliminary study shows the promising results of antlerogenic stem cells of Cervus elaphus topically applied for the treatment of corneal injury. A deeper understanding of the developmental mechanisms involved in antler renewal can be useful for controlling regeneration cornea processes.

Transregional autologous serum eye drop provision by a large German Red Cross Blood Donation Service

BACKGROUND

The Blood Donation Service West serves North Rhine-Westphalia (NRW), Rhineland-Palatinate (RP), and Saarland, an area of 56,500 km². In addition to routine red blood cell concentrates, plasma, and platelets, special products are provided. Since 2014, this has included autologous serum eye drops (ASED) for topical use in patients suffering from different illnesses accompanied by dry eye disease.

METHODS

A volume of 250-525 mL of patient blood was collected into an anticoagulant-free blood bag. Laboratory testing included Hepatitis B/C-, HIV 1/2-, and Lues-serology. Coagulation and centrifugation were followed by leukoreduction. Single-use vials were obtained by filling mini-bag systems using a sterile tube welder. Storage at ≤-20 °C enabled a shelf-life of up to 6 months and 30 days at 4 °C after thawing for shipment.

RESULTS

Contracts were closed with 15 ophthalmology clinics and medical practices in NRW and RP to supply patients with ASED. The patient pool increased from 19 in 2014 to 46 in 2020, with an average age of 43-55 years. Overall, blood collections almost tripled from 31 to 100 per year, increasing the stock of deliverable single-use vials from 3328 to 13,358. Delivery in a liquid state allowed engagement of 44 pharmacies located in the patient neighborhoods for continuous supply.

CONCLUSION

Manufacturing in a closed bag system allowed integration into blood bank operations. However, cost-coverage by health insurance remained a case-by-case decision. Allogeneic application as 'just-another-blood-product' could be an aspiration. Yet, conclusive data from large clinical trials are needed for licensed provision in Germany.

Stabilization of eye drops containing autologous serum and recombinant human epidermal growth factor for dry eye syndrome

Human epidermal growth factor (hEGF) and autologous serum are considered safer and more effective in treating dry eye syndrome. However, suitable formulas and preparation methods are needed to obtain eye drop containing autologous serum and hEGF, which are stable during storage and use. Therefore, this study aimed to develop a stable and effective eye drops containing autologous serum and hEGF. Stabilization of autologous serum and hEGF was done by adding lyoprotectant and antioxidant agents, and then prepared using the freeze-drying method. The clarity, pH, sterility, and endotoxin content of the preparation were evaluated. The effectiveness of the preparation was assessed by a cell viability test using a WST-8 reagent. Based on the results, all formulas produce preparations that are isotonic, clear, sterile, stable, and free from endotoxins. Cell viability test shows the addition of 25 μg/mL hEGF increased epithelial cell proliferation by up to 197%. It can be concluded that eye drops containing autologous serum and 25 μg/mL hEGF can be a promising therapy for dry eye syndrome.

Serum eye drops for the treatment of ocular surface diseases: a systematic review and meta-analysis

BACKGROUND

The use of blood-derived eye drops for topical treatment of ocular surface diseases has progressively increased in recent years.

MATERIALS AND METHODS

To evaluate the use of serum eye drops in ocular surface disorders, we performed a systematic search of the literature.

RESULTS

In this systematic review, we included 19 randomised controlled trials (RCTs) investigating the use of serum eye drops in 729 patients compared to controls. For the quantitative synthesis, we included only 10 RCTs conducted in patients with dry eye syndrome comparing autologous serum to artificial tears. At 2-6 weeks, no clear between-group differences in Schirmer test (MD 1.05; 95% CI: -0.17-2.26) and in fluorescein staining (MD -0.61; 95% CI: -1.50-0.28) were found (very low-quality evidence, down-graded for inconsistency, serious risk of biases, and serious imprecision). Slightly higher increase in tear film break-up time (TBUT) scores in autologous serum compared to control (MD 2.68; 95% CI: 1.33-4.03), and greater decrease in ocular surface disease index (OSDI) in autologous serum compared to control (MD -11.17; 95% CI: -16.58 - -5.77) were found (low quality evidence, down-graded for serious risk of bias, and for inconsistency). For the Schirmer test, fluorescein staining and TBUT, data were also available at additional follow-up timing (2-12 months): no clear between-group differences were found, and the quality of the evidence was graded as low/very-low.

CONCLUSIONS

In patients with dry eye syndrome, it is unclear whether or not the use of autologous serum compared to artificial tears increases Schirmer test and fluorescein staining scores at short-term and medium-/long-term follow up. Some benefit at short-term follow up for the outcome of TBUT and OSDI was observed, but the quality of the evidence was low.

The use of autologous serum eye drops for the treatment of ocular surface disorders

Objectives

To investigate the use of autologous serum (AS) eye drops in patients with ocular surface disorders who were refractory to conventional treatments.

Methods

A retrospective cohort study was conducted at a tertiary care centre. We included patients with a prescription of AS eye drops from December 2006 to January 2016. Electronic prescriptions (Prescriplant) and clinical histories were reviewed. A database with sociodemographic and pharmacotherapheutic variables was created. The efficacy was evaluated subjectively and adverse effects was a measurement of safety. AS eye drops were elaborated, in a laminar flow hood, with the blood samples for a final concentration of 20%.

Results

One hundred and seventy-three patients were considered for the study, 78.03% of them female. Their mean age was 63.87 years (SD 16.69). The use of AS eye drops was indicated for several diseases: corneal diseases (corneal ulcer or corneal persistent epithelial defects) (34.32%); Sjögren syndrome (17.16%); dry eye resulting from autoimmune disease (15.38%); and blepharitis/blepharospasm (12.43%). The regular dosage was every 3 or 4 hours (40.46%). 21.97% patients used the AS in one eye only. The mean length of treatment was 2.71 years. All patients, except one, improved their symptoms with the treatment and no one suffered harmful effects.

Conclusions

Numerous national and international guidelines on dry eye treatment have been published, but they differ in dosing, concentration and indication of AS eye drops. Consequently, there is no consensus about the best therapy with AS. In this article we describe the clinical practice of AS eye drops. In the study, indications for AS therapy were mostly: corneal diseases; Sjögren syndrome; and dry eye resulting from autoimmune disease; and blepharitis or blepharospasm. Patients went to the hospital pharmacy to pick up AS eye drops before 90 days, it ensures the stability of eye drops. AS is an effective, safe and well tolerated treatment.

MG53 promotes corneal wound healing and mitigates fibrotic remodeling in rodents

The cornea plays an important role in transmitting light and providing protection to the eye, but is susceptible to injury and infection. Standard treatments for corneal wounds include topical lubricants, antibiotics, bandage contact lens, and surgery. However, these measures are often ineffective. Here we show that MG53, a protein with an essential role in cell membrane repair, contributes to the corneal injury-repair process. Native MG53 is present in the corneal epithelia, tear film, and aqueous humor, suggesting its potential function in corneal homeostasis. Knockout of MG53 in mice causes impaired healing and regenerative capacity following injury. Exogenous recombinant human MG53 (rhMG53) protein protects the corneal epithelia against mechanical injury and enhances healing by promoting migration of corneal fibroblasts. Using in vivo alkaline-induced injury to the rat cornea, we show that rhMG53 promotes re-epithelialization and reduces post-injury fibrosis and vascularization. Finally, we show that rhMG53 modulates TGF-β-mediated fibrotic remodeling associated with corneal injury. Overall, our data support the bi-functional role of MG53 in facilitating corneal healing and maintaining corneal transparency by reducing fibrosis and vascularization associated with corneal injuries.

Heather Chandler, Tao Tan, Chunlin Yang et al. find that the cell membrane repair protein MG53 plays a key role in repairing cornea injury. Using mouse and rat models, they show that recombinant human MG53 protects the cornea against injury and enhances healing.

Detection of neopterin in tear samples

The main goal of the present study was to detect neopterin concentrations in human tear samples and to evaluate its potential correlation with serum neopterin levels. For this purpose, 20 systemically healthy volunteers were recruited, and both tear and serum samples were synchronically collected from each individual. Enzyme-linked immunoassay (ELISA) was carried out to detect the quantity of neopterin in the samples. Mean human tear neopterin levels were observed as 3±0.56 nM while mean serum neopterin was 9±1.25 nM. Additionally, a significant positive correlation between tear neopterin and serum neopterin concentrations was observed. This is the first report to show neopterin concentration in human tears as a biological sample. Collecting tears from the individuals is a non-invasive sampling method, and as an analytical aspect detection of neopterin by ELISA in tear samples construct a valuable, practical and cheap procedure for the diagnosis and monitoring of intraocular inflammation and systemic immune-mediated diseases.