Tissue-Specific Immune Transcriptional Signatures in the Bordering Tissues of the Mouse Retina and Brain.

Purpose: Bordering the central nervous system (CNS) parenchyma are the choroid (underlying the retina) and the leptomeninges (the inner layers of the meninges enveloping the brain). Although near the neural parenchyma, the choroid and leptomeninges are external to the immune privileged environment of the retina and brain and thus are distinct immune compartments. This study aimed to characterize the transcriptomic signatures of immune cells within the choroid and leptomeninges bordering the healthy adult mouse CNS.

Proteomic Characterization of Transfusable Blood Components: Fresh Frozen Plasma, Cryoprecipitate, and Derived Extracellular Vesicles via Data-Independent Mass Spectrometry.

Extracellular vesicles (EVs) are a heterogeneous collection of particles that play a crucial role in cell-to-cell communication, primarily due to their ability to transport molecules, such as proteins. Thus, profiling EV-associated proteins offers insight into their biological effects. EVs can be isolated from various biological fluids, including donor blood components such as cryoprecipitate and fresh frozen plasma (FFP).

Extracellular vesicles in fresh frozen plasma and cryoprecipitate: Impact on in vitro endothelial cell viability.

Background: Transfusion-related acute lung injury (TRALI) remains a major contributor to transfusion-associated mortality. While the pathogenesis of TRALI remains unclear, there is evidence of a role for blood components. We therefore investigated the potential effects of fresh frozen plasma (FFP), cryoprecipitate, and extracellular vesicles (EVs) derived from these blood components, on the viability of human lung microvascular endothelial cells (HLMVECs) in vitro.

Non-invasive imaging of brain and retinal microglia in neurodegenerative diseases.

Microglia play crucial roles in immune responses and contribute to fundamental biological processes within the central nervous system (CNS). In neurodegenerative diseases, microglia undergo functional changes and can have both protective and pathogenic roles. Microglia in the retina, as an extension of the CNS, have also been shown to be affected in many neurological diseases.

Comparison of penetrating and endothelial keratoplasty in patients with iridocorneal endothelial syndrome: A registry study.

Background: To compare graft survival of endothelial keratoplasty (EK) versus penetrating keratoplasty (PK) in patients with iridocorneal endothelial (ICE) syndrome and identify ocular features associated with graft survival.

Methods: Observational, prospective, cohort study. A total of 30 806 first grafts performed between 1985 and 2020 were identified through the Australian Corneal Graft Registry and included in this observational, prospective cohort study.

Investigation of the effect of pre-analytical factors on particle concentration and size in cryoprecipitate using nanoparticle tracking analysis.

Background: Cryoprecipitate is used primarily to replenish fibrinogen levels in patients. Little is known about the presence of micro- or nano-sized particles in cryoprecipitate. Therefore, we aimed to quantify these particles and investigate some pre-analytical considerations.

Membranes Prepared from Recombinant RGD-Silk Fibroin as Substrates for Human Corneal Cells.

A recombinant formulation of silk fibroin containing the arginine-glycine-aspartic acid (RGD) cell-binding motif (RGD-fibroin) offers potential advantages for the cultivation of corneal cells. Thus, we investigated the growth of corneal stromal cells and epithelial cells on surfaces created from RGD-fibroin, in comparison to the naturally occurring silk fibroin. The attachment of cells was compared in the presence or absence of serum over a 90 min period and analyzed by quantification of dsDNA content.

Effect of Rho-Associated Protein Kinase Inhibitors on Epidermal Keratinocytes: A Proposed Application for Burn Wound Healing.

Rho-associated protein kinases (ROCKs) affect a variety of cellular functions, including cell attachment, migration, and proliferation. ROCK inhibitors therefore have potential as tools for optimizing cell behavior in tissue engineering applications, including the manufacturing of cultivated epithelial autografts (CEAs) used in the treatment of burn patients. For example, ROCK inhibitors may facilitate earlier engraftment of CEA sheets by increasing the proliferation of skin keratinocytes .

Poly(2-allylamidopropyl-2-oxazoline)-Based Hydrogels: From Accelerated Gelation Kinetics to Compatibility in a Murine Subdermal Implant Model.

A rapid photo-curing system based on poly(2-ethyl-2-oxazoline--2-allylamidopropyl-2-oxazoline) and its compatibility are presented. The base polymer was synthesized from the copolymerization of 2-ethyl-2-oxazoline (EtOx) and the methyl ester containing 2-methoxycarboxypropyl-2-oxazoline (CMestOx) followed by amidation with allylamine to yield a highly water-soluble macromer. We showed that spherical hydrogels can be obtained by a simple water-in-oil gelation method using thiol-ene coupling and investigated the biocompatibility of these hydrogel spheres in a 28-day murine subdermal model.

Stromal cells cultivated from the choroid of human eyes display a mesenchymal stromal cell (MSC) phenotype and inhibit the proliferation of choroidal vascular endothelial cells in vitro.

Mesenchymal stromal cells (MSC), with progenitor cell and immunological properties, have been cultivated from numerous vascularized tissues including bone marrow, adipose tissue and the corneal-limbus of the eye. After observing mesenchymal cells as contaminants in primary cultures of vascular endothelial cells derived from the choroidal tunic of the human eye, we investigated whether the choroid might also provide a source of cultured MSC. Moreover, we examined the effect of the choroidal stromal cells (Ch-SC) on the proliferation of freshly isolated choroidal vascular endothelial cells (ChVEC) in vitro.

Hydrogels with Cell Adhesion Peptide-Decorated Channel Walls for Cell Guidance.

A method is reported for making hollow channels within hydrogels decorated with cell-adhesion peptides exclusively at the channel surface. Sacrificial fibers of different diameters are used to introduce channels within poly(ethylene glycol) hydrogels crosslinked with maleimide-thiol chemistry, which are backfilled with a cysteine-containing peptide solution which is conjugated to the lumen with good spatial efficiency. This allows for peptide patterning in only the areas of the hydrogel where they are needed when used as cell-guides, reducing the amount of required peptide 20-fold when compared to bulk functionalization.

Growth of Human and Sheep Corneal Endothelial Cell Layers on Biomaterial Membranes.

Corneal endothelial cell cultures have a tendency to undergo epithelial-to-mesenchymal transition (EMT) after loss of cell-to-cell contact. EMT is deleterious for the cells as it reduces their ability to form a mature and functional layer. Here, we present a method for establishing and subculturing human and sheep corneal endothelial cell cultures that minimizes the loss of cell-to-cell contact.

Optimization of silk fibroin membranes for retinal implantation.

Silk fibroin membrane displays potential for ocular tissue reconstruction as demonstrated by its ability to support a functioning retinal pigment epithelium (RPE) in vitro. Nevertheless, translation of these findings to the clinic will require the use of membranes that can be readily handled and implanted into diseased retinas, with minimal impact on the surrounding healthy tissue. To this end, we optimized the physical properties of fibroin membranes to enable surgical handling during implantation into the retina, without compromising biocompatibility or permeability.

Further Investigations on the Crosslinking of Tarsal Collagen as a Treatment for Eyelid Laxity: Optimizing the Procedure in Animal Tissue.

Purpose: A follow-up experimental study on the exposure of animal tarsal plate to ultraviolet-A radiation aimed at establishing an optimum range for safe irradiation conditions.

Methods: Sheep tarsus specimens were excised postmortem and then subjected to irradiation with ultraviolet-A rays (wavelength 365 nm) at higher irradiances than those reported in an initial study, using a laboratory radiation source. The mechanical properties (tensile strength and Young's modulus) of irradiated and nonirradiated samples were evaluated in a mechanical tester.

The Impact of Limbal Mesenchymal Stromal Cells on Healing of Acute Ocular Surface Wounds Is Improved by Pre-cultivation and Implantation in the Presence of Limbal Epithelial Cells.

While limbal epithelial cells are used for treating ocular surface wounds, the therapeutic potential of mesenchymal cells cultivated from the limbal stroma (LMSC) is less clear. We have therefore examined the effects of LMSC when applied to acute ocular surface wounds. LMSC derived from male rabbits (RLMSC) were applied to the ocular surface of female rabbits immediately following removal of the corneal and limbal epithelium.

Demonstration of P-selectin expression and potential function in human corneal epithelial cells.

In response to an unexpected observation of apparent localisation by immunocytochemistry, we have investigated the potential expression and function of P-selectin (CD62P) in human corneal epithelial cells. The SV40 immortalised cell line, HCE-T (validated by STR profiling), along with multiple donor corneal-limbal tissue samples, were examined for P-selectin expression using a combination of immunocytochemistry, Western blotting, RT-PCR and immunohistochemistry. Potential expression of the major ligand for P-selectin (P-selectin glycoprotein ligand-1; PSGL-1; CD162) was also examined by immunocytochemistry and RT-PCR.

Characterization of Human iPSC-RPE on a Prosthetic Bruch's Membrane Manufactured From Silk Fibroin.

Purpose: RPE cell transplantation as a potential treatment for AMD has been extensively investigated; however, in AMD, ultrastructural damage affects both the RPE and its underlying matrix support, the Bruch's membrane (BrM). An RPE monolayer supported by a surrogate scaffold could thus provide a more effective approach to cell-based therapy for AMD. Toward this goal, we aimed to establish a functional human induced pluripotent stem cell-derived (hiPSC)-RPE monolayer on a Bombyx mori silk fibroin (BMSF) scaffold.

Cultivation of corneal endothelial cells from sheep.

Research is currently under way to produce tissue engineered corneal endothelium transplants for therapeutic use in humans. This work requires the use of model animals, both for the supply of corneal endothelial cells (CECs) for experimentation, and to serve as recipients for test transplants. A variety of species can be used, however, a number of important advantages can be gained by using sheep as transplant recipients.

A potential role for Eph receptor signalling during migration of corneal endothelial cells.

The corneal endothelium is a monolayer of epithelial cells that lines the posterior surface of the cornea and is essential for maintenance of corneal transparency. Wound healing within the corneal endothelium typically occurs through cell spreading and migration rather than through proliferation. The mechanisms that control corneal endothelial cell migration are unclear.

Mounting of Biomaterials for Use in Ophthalmic Cell Therapies.

When used as scaffolds for cell therapies, biomaterials often present basic handling and logistical problems for scientists and surgeons alike. The quest for an appropriate mounting device for biomaterials is therefore a significant and common problem. In this review, we provide a detailed overview of the factors to consider when choosing an appropriate mounting device including those experienced during cell culture, quality assurance, and surgery.

Impact of oral vitamin D supplementation on the ocular surface in people with dry eye and/or low serum vitamin D.

Purpose: To determine the possible association between serum vitamin D levels and dry eye symptoms, and the impact of an oral vitamin D supplement.

Methods: Three linked studies were performed. (i) 29 older adult participants, (ii) 29 dry eyed participants, and (iii) 2-month vitamin D supplementation for 32 dry eyed/low serum vitamin D levelled participants.

Optimization of Corneal Epithelial Progenitor Cell Growth on Bombyx mori Silk Fibroin Membranes.

Scaffolds prepared from silk fibroin derived from cocoons of the domesticated silkworm moth Bombyx mori have demonstrated potential to support the attachment and growth of human limbal epithelial (HLE) cells in vitro. In this study, we attempted to further optimize protocols to promote the expansion of HLE cells on B. mori silk fibroin- (BMSF-) based scaffolds.