Publications
Here is a selection of publications where different laminin isoforms were used to create more authentic cell culture systems.
Submacular integration of hESC-RPE monolayer xenografts in a surgical non-human primate model
Zengping Liu, Tanja Ilmarinen, Gavin S. W. Tan, Heidi Hongisto, Edmund Y. M. Wong, Andrew S. H. Tsai, Sami Al-Nawaiseh, Graham E. Holder, Xinyi Su, Veluchamy Amutha Barathi, Heli Skottman & Boris V. Stanzel Stem Cell Research & Therapy, 2021
This surgical xenotransplantation study addressed logistical, surgical, and immunosuppression-related issues in cell therapy. Biolaminin 521 -coated transplant sheets with live stem-cell-derived retinal pigment epithelium (RPE) cells were transported from the manufacturing site (Finland) to the transplantation site (Singapore), taking more than 30 hours, without any alterations in cell quality. Laminin-521 was also part of the clinically compliant differentiation protocol from embryonic stem cells to RPE cells. The process overall resulted in functional submacular xenograft integrations.
Culture surface protein coatings affect the barrier properties and calcium signalling of hESC-RPE
Taina Viheriälä, Juhana Sorvari, Teemu O. Ihalainen, Anni Mörö, Pyry Grönroos, Sabrina Schlie-Wolter, Boris Chichkov, Heli Skottman, Soile Nymark & Tanja Ilmarinen Scientific Reports, 2021
Biolaminin 521 was shown to significantly improve hESC-derived retinal pigment epithelial cell attachment and the formation of an intact epithelium after cryopreservation. Laminin-521 significantly improved cell attachment and epithelium barrier properties when compared to collagen (Col-IV) alone. The cryopreserved cells attached poorly to collagen only. Laminin was thus able to provide the needed support for differentiated therapeutic cells which usually require cryostorage before transplantation.
Endothelial basement membrane limits tip cell formation by inducing Dll4/Notch signaling in vivo
Stenzel D., Franco C.A., Estrach S., Mettouchi A., Sauvaget D., Rosewell I., Schertel A., Armer H., Domogatskaya A., Rodin S., Tryggvason K., Collinson L., Sorokin L., Gerhardt H. EMBO reports, 2011
Here the authors show that laminin α4 regulates tip cell numbers and vascular density by inducing endothelial Dll4/Notch signaling in vivo deficiency leads to reduced Dll4 expression, excessive filopodia and tip cell formation in the mouse retina, phenocopying the effects of Dll4/Notch inhibition. Lama4-mediated Dll4 expression requires a combination of integrins in vitro and integrin β1 in vivo. The authors conclude that appropriate laminin/integrin‐induced signaling is necessary to induce physiologically functional levels of Dll4 expression and regulate branching frequency during sprouting angiogenesis.
Xeno- and feeder-free differentiation of human pluripotent stem cells to two distinct ocular epithelial cell types using simple modifications of one method
Hongisto H., Ilmarinen T., Vattulainen M., Mikhailova A., Skottman H. Stem cell research and therapy, 2017
Here the authors describe a robust xeno- and feeder cell-free culture system for undifferentiated hPSCs along with efficient and scalable methods to derive high-quality retinal pigment epithelial (RPE) cells and corneal limbal epithelial stem cells (LESCs). Multiple genetically distinct hPSC lines were adapted to a robust, defined, xeno-, and feeder-free culture system of Essential 8™ medium and laminin-521 matrix. Thereafter, two-stage differentiation methods toward ocular epithelial cells were established utilizing xeno-free media and a combination of extracellular matrix proteins laminin-521 and Collagen IV. Derivative RPE formed functional epithelial monolayers with mature tight junctions and expression of RPE genes and proteins, as well as phagocytosis and key growth factor secretion capacity after 9 weeks of maturation on inserts. Efficient LESC differentiation led to cell populations expressing LESC markers such as p40/p63α by day 24. Finally, the authors established xeno-free cryobanking protocols for pluripotent hPSCs, hPSC-RPE cells, and hPSC-LESCs, and demonstrated successful recovery after thawing on laminin-521 and Collagen IV. The simple xeno-free methods described here could be upgraded to GMP-quality for future preclinical testing and safety and functional efficacy testing of the hPSC-RPE and hPSC LESCs produced with these protocols are currently ongoing in non-human primates and rabbit models of LSCD, respectively.
Long-Term Efficacy of GMP Grade Xeno-Free hESC-Derived RPE Cells Following Transplantation
McGill T.J., Bohana-Kashtan O., Stoddard J.W., Andrews M.D., Pandit N., Rosenberg-Belmaker L.R., Wiser O., Matzrafi L., Banin E., Reubinoff B., Netzer N., Irving C. Trans Vis Sci Tech., 2017
Publication from researchers at Cell Cure Neurosciences where they display the efficacy of RPE cells derived under xeno-free conditions from clinical and xeno-free grade human embryonic stem cells following transplantation into the subretinal space of Royal College of Surgeons (RCS) rats. BioLamina’s laminin cell culture substrate is being used in the differentiation protocol. The results of this study demonstrate that the transplantation of OpRegen into the subretinal space of RCS rats protected the retinal structure, rescued visual function, preserved rod and cone photoreceptors long-term (up to 180 days). Transplanted RPE cells were identified in both the subretinal space and integrated into the host RPE monolayer in animals of all age groups, and often contained internalized photoreceptor outer segments. Optomotor tracking was rescued in a dose-dependent manner. The outer nuclear layer was significantly thicker in cell-treated eyes than controls up to P150. No pathology was observed. This data combined with data collected in definitive safety studies (tumorigenicity and spiking and safety/biodistribution) has resulted in an FDA approved IND and a Phase 1/2a clinical trial for AMD patients is ongoing, NCT02286089.