The conjunctival extracellular matrix, related disorders and development of substrates for conjunctival restoration

Bogerd

et al. 2021

IJMS

Self Cite

One key element to the health of the ocular surface encompasses the presence of gel-forming mucins in the pre-ocular tear film. Conjunctival goblet cells are specialized epithelial cells that secrete mucins necessary for tear film stability and general homeostasis. Their dysfunction can be linked to a range of ocular surface inflammation disorders and chronic injuries. To obtain new perspectives and angles to tackle mucin deficiency, the need for an accurate evaluation of their presence and corresponding mucin secretion in ex vivo conjunctival cultures has become a requisite. In vitro, goblet cells show a significant decrease in the production and secretion of gel-forming mucins, accompanied by signs of dedifferentiation or transdifferentiation. Explant cultures on laminin-treated CLP-PEG hydrogels can, however, support the production of gel-forming mucins. Together, we challenge the current paradigm to evaluate the presence of cultured goblet cells solely based on their general mucin (MUC) content through imaging analyses, showing the need for additional techniques to assess the functionality of goblet cells. In addition, we broadened the gel-forming mucin profile of in vivo goblet cells with MUC5B and MUC6, while MUC2 and MUC6 is added to the profile of cultured goblet cells.

Section: Discussionmentioning

confidence: 99%

Section: Substrate-based Culture Technologies To Improve Goblet Cell Functionalitymentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Characterisation of Gel-Forming Mucins Produced In Vivo and In Ex Vivo Conjunctival Explant Cultures

Bogerd

et al. 2021

IJMS

Self Cite

“…Commonly used graft tissues such as human amniotic membrane or autologous mucous membrane have certain drawbacks, including limited availability, time-consuming preparation, and inconsistent tissue properties such as thickness or growth factor content, which have led to an increased focus on alternative tissues and materials [ 3 , 4 , 5 , 6 , 7 , 8 ]. In this context, extracellular matrix-based biomaterials and decellularized tissues are becoming more important and have already been used clinically [ 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. The biochemical composition of the extracellular matrix is unique for every organ and has an effect on specific tissue properties and cell–matrix interactions [ 16 , 17 , 18 ].…”

Section: Introductionmentioning

confidence: 99%

Influence of Storage Conditions on Decellularized Porcine Conjunctiva

et al. 2023

Porcine decellularized conjunctiva (PDC) represents a promising alternative source for conjunctival reconstruction. Methods of its re-epithelialization in vitro with primary human conjunctival epithelial cells (HCEC) have already been established. However, a long-term storage method is required for a simplified clinical use of PDC. This study investigates the influence of several storage variants on PDC. PDC were stored in (1) phosphate-buffered saline solution (PBS) at 4 °C, (2) in glycerol-containing epithelial cell medium (EM/gly) at −80 °C and (3) in dimethyl sulfoxide-containing epithelial cell medium (EM/DMSO) at −196 °C in liquid nitrogen for two and six months, respectively. Fresh PDC served as control. Histological structure, biomechanical parameters, the content of collagen and elastin and the potential of re-epithelialization with primary HCEC under cultivation for 14 days were compared (n = 4–10). In all groups, PDC showed a well-preserved extracellular matrix without structural disruptions and with comparable fiber density (p ≥ 0.74). Collagen and elastin content were not significantly different between the groups (p ≥ 0.18; p ≥ 0.13, respectively). With the exception of the significantly reduced tensile strength of PDC after storage at −196 °C in EM/DMSO for six months (0.46 ± 0.21 MPa, p = 0.02), no differences were seen regarding the elastic modulus, tensile strength and extensibility compared to control (0.87 ± 0.25 MPa; p ≥ 0.06). The mean values of the epithelialized PDC surface ranged from 51.9 ± 8.8% (−196 °C) to 78.3 ± 4.4% (−80 °C) and did not differ significantly (p ≥ 0.35). In conclusion, all examined storage methods were suitable for storing PDC for at least six months. All PDC were able to re-epithelialize, which rules out cytotoxic influences of the storage conditions and suggests preserved biocompatibility for in vivo application.

Stem Cells International

“…The conjunctiva is essential in the healthy ocular surface and provides a physical and an immunological barrier promoting innate and adaptive immunity [ 1 ]. Severe conjunctival damage, such as ocular cicatricial pemphigoid and Stevens-Johnson syndrome, trauma, and thermal or chemical burns, leads to severe ocular surface scarring and need a suitable substitute for surgical reconstruction of functional fornixes and conjunctiva.…”

Section: Introductionmentioning

confidence: 99%

Crosslinked Decellularized Porcine Pericardium as a Substrate for Conjunctival Reconstruction

Chen

Deng

Luo

et al. 2022

Seeking for suitable conjunctival reconstruction substitutes to overcome the limitations of current substitutes, such as amniotic membrane, is urgent. Decellularized tissues have become a promising strategy for tissue engineering. In this study, we prepared decellularized porcine pericardium (DPP) scaffolds by the phospholipase A2 method and crosslinked them with aspartic acid (Asp) and human endothelial growth factor (hEGF) to enhance biological performance on the DPP, obtaining DPP-Asp-hEGF scaffolds. In vitro DPP showed lower apoptosis, highly desirable, well preservation of extracellular matrix components, and favorable macro-microstructure, which was confirmed by histology, immunofluorescence, electron microscopy, collagen and DNA quantification, and cytotoxicity assay, compared to the native porcine pericardium (NPP). The crosslinked efficacy of the DPP-Asp-hEGF was furtherer verified by in vitro experiments with Fourier transform infrared (FTIR) and X-ray diffraction (XRD). Through animal models of conjunctiva defect model, the DPP-Asp-hEGF revealed a closed, multilayer epithelium with an equal amount of goblet cells and no indication for conjunctival scarring after 28 days, compared to amniotic membrane (AM) groups and sham groups. These results suggested that DPP-Asp-hEGF can offer a good conjunctival reconstructive substitute both in structure and in function.