TY - JOUR A1 - Waxman, Susannah A1 - Strzalkowska, Alicja A1 - Wang, Chao A1 - Loewen, Ralitsa A1 - Dang, Yalong A1 - Loewen, Nils A. T1 - Tissue-engineered anterior segment eye cultures demonstrate hallmarks of conventional organ culture JF - Graefe’s Archive for Clinical and Experimental Ophthalmology N2 - Background Glaucoma is a blinding disease largely caused by dysregulation of outflow through the trabecular meshwork (TM), resulting in elevated intraocular pressure (IOP). We hypothesized that transplanting TM cells into a decellularized, tissue-engineered anterior segment eye culture could restore the outflow structure and function. Methods Porcine eyes were decellularized with freeze–thaw cycles and perfusion of surfactant. We seeded control scaffolds with CrFK cells transduced with lentiviral vectors to stably express eGFP and compared them to scaffolds seeded with primary TM cells as well as to normal, unaltered eyes. We tracked the repopulation behavior, performed IOP maintenance challenges, and analyzed the histology. Results Transplanted cells localized to the TM and progressively infiltrated the extracellular matrix, reaching a distribution comparable to normal, unaltered eyes. After a perfusion rate challenge to mimic a glaucomatous pressure elevation, transplanted and normal eyes reestablished a normal intraocular pressure (transplanted = 16.5 ± 0.9 mmHg, normal = 16.9 ± 0.9). However, eyes reseeded with eGFP-expressing CrFK cells could not regulate IOP, remaining high and unstable (27.0 ± 6.2 mmHg) instead. Conclusion Tissue-engineered anterior segment scaffolds can serve as readily available, scalable ocular perfusion cultures. This could reduce dependency on scarce donor globes in outflow research and may allow engineering perfusion cultures with specific geno- and phenotypes. KW - ocular anterior segment perfusion culture KW - tissue engineering KW - aqueous humor outflow KW - trabecular meshwork Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-323845 VL - 261 IS - 5 ER - TY - THES A1 - Verma-Führing, Raoul T1 - Die Trabekulopunktion als Prädiktiver Test für den Erfolg der Ab Interno Trabekulektomie im Schweineaugenmodell T1 - Trabeculopuncture as Predictive Test for the Outcome of Ab Interno Trabeculectomy in Porcine Anterior Segments N2 - To investigate trabeculopuncture (TP) for predicting the outcome of ab interno trabeculectomy (AIT). Ex vivo porcine anterior segments were perfused and sequentially underwent two procedures, TP and AIT. We concluded that a 10% reduction in IOP after TP can be used to predict the success (>20% IOP decrease) of AIT in porcine eyes. As porcine eyes share many similarities with human eyes, our findings may have implications on the validity of this test as a predictor for surgical outcomes of AITs in humans. N2 - Wir untersuchten die Trabekulopunktion (TP) zur Vorhersage des Erfolgs einer Ab Interno Trabekulektomie (AIT) an einem ex vivo Schweineaugen-Perfusionsmodell. Die Schweineaugen wurden nacheinander zwei Verfahren (TP und AIT) unterzogen. Wir kamen zu dem Schluss, dass eine 10-prozentige Senkung des Augeninnendrucks nach der TP zur Vorhersage des Erfolgs (>20-prozentige Senkung des Augeninnendrucks) einer AIT in Schweineaugen verwendet werden kann. Schweineaugen weisen viele Ähnlichkeiten mit menschlichen Augen auf. Die Implementation eines solchen Tests zur Vorhersage des chirurgischen Erfolgs einer AIT beim Menschen wäre von hoher klinischer Relevanz. KW - Glaukom KW - Goniotomie KW - Ab Interno Trabekulektomie KW - Trabekulopunktion KW - Glaucoma KW - trabecular meshwork KW - trabeculopuncture KW - ab interno trabeculectomy Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-282633 ER - TY - JOUR A1 - Han, Hong A1 - Kampik, Daniel A1 - Grehn, Franz A1 - Schlunck, Günther T1 - TGF-beta 2-Induced Invadosomes in Human Trabecular Meshwork Cells JF - PLoS ONE N2 - Primary open-angle glaucoma (POAG) is a leading cause of blindness due to chronic degeneration of retinal ganglion cells and their optic nerve axons. It is associated with disturbed regulation of intraocular pressure, elevated intraocular levels of TGF-β2, aberrant extracellular matrix (ECM) deposition and increased outflow resistance in the trabecular meshwork (TM). The mechanisms underlying these changes are not fully understood. Cell-matrix interactions have a decisive role in TM maintenance and it has been suggested that TGF-β-induced inhibition of matrix metalloproteases may drive aberrant ECM deposition in POAG. Invadopodia and podosomes (invadosomes) are distinct sites of cell-matrix interaction and localized matrix-metalloprotease (MMP) activity. Here, we report on the effects of TGF-β2 on invadosomes in human trabecular meshwork cells. Human TM (HTM) cells were derived from donor tissue and pretreated with vehicle or TGF-β2 (2 ng/ml) for 3d. Invadosomes were studied in ECM degradation assays, protein expression and MMP-2 activity were assessed by western blot and zymography and ECM protein transcription was detected by RT-qPCR. HTM cells spontaneously formed podosomes and invadopodia as detected by colocalization of Grb2 or Nck1 to sites of gelatinolysis. Pretreatment with TGF-β2 enhanced invadosomal proteolysis and zymographic MMP-2 activity as well as MMP-2, TIMP-2 and PAI-1 levels in HTM cell culture supernatants. Rho-kinase inhibition by H1152 blocked the effects of TGF-β2. Concomitant transcription of fibronectin and collagens-1, -4 and -6 was increased by TGF-β2 and fibrillar fibronectin deposits were observed in areas of invadosomal ECM remodelling. In contrast to a current hypothesis, our data indicate that TGF-β2 induces an active ECM remodelling process in TM cells, characterized by concurrent increases in localized ECM digestion and ECM expression, rather than a mere buildup of material due to a lack of degradation. Invadosomal cell adhesion and signaling may thus have a role in POAG pathophysiology. KW - intraocular pressure KW - cell cultures KW - cell staining KW - proteolysis KW - glaucoma KW - extracellular matrix KW - actins KW - trabecular meshwork Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-130074 VL - 8 IS - 8 ER -