Here is a selection of publications where different laminin isoforms were used to create more authentic cell culture systems.
Generation of 3D retinal tissue from human pluripotent stem cells using a directed small molecule-based serum-free microwell platform
Hassan Rashidi, Yeh Chwan Leong, Kerrie Venner, Hema Pramod, Qi-Zhen Fei, Owen J. R. Jones, Dale Moulding & Jane C. Sowden Scientific Reports, 2022
Biolaminin 521 (LN521) was used as the matrix in a 2D/3D system for retinal differentiation from human pluripotent stem cells in an agarose micromould platform. To achieve a serum-free and animal-free protocol for producing retinal tissue with photoreceptor cells, the scientists successfully replaced Matrigel (which is derived from mouse tumor cells) with laminin-521, and fetal bovine serum (FBS) with human platelet lysate (HPL). The culture system first allows cells to self-organize forming neuroepithelial structures that resemble embryonic optic vesicles, and then mimics retinogenesis and produces retinal tissue with photoreceptor cells. The generated photoreceptors exhibited key photoreceptor cell features including the formation of OS-like structures containing proteins involved in phototransduction.
Laminins containing the β2 and γ3 chains regulate astrocyte migration and angiogenesis in the retina
Gnanaguru G., Bachay G., Biswas S., Pinzón-Duarte G., Hunter D.D. Brunken W.J.Development, 2013
Astrocytes regulate retinal vascular development. Generated extrinsically to the retina, astrocytes migrate into the retina through the optic nerve head. In this study, we show that astrocytes migrate within a laminin-containing basement membrane. Genetic deletion of the laminin β2 and γ3 chains affects astrocyte migration and spatial distribution. We show that laminins act as haptotactic factors in vitro in an isoform-specific manner, inducing astrocyte migration and promoting astrocyte differentiation. The addition of exogenous laminins to laminin-null retinal explants rescues astrocyte migration and spatial patterning. Furthermore, we show that the loss of laminins reduces β1 integrin expression in astrocytes which can be restored when astrocytes are cultured on Biolaminin 521 or Matrigel. Finally, they show that laminins containing β2 and γ3 chains regulate subsequent retinal blood vessel growth and maintain vascular integrity. These in vivo and in vitro studies demonstrate clearly that laminins containing β2 and γ3 chains are indispensable for migration and spatial organization of astrocytes and that they play a crucial role during retinal angiogenesis in vivo.
Laminin Expression in Adult and Developing Retinae: Evidence of Two Novel CNS Laminins
Libby R.T., Champliaud M-F, Claudepierre T., Xu Y., Gibbons E.P., Koch M., Burgeson R.E., Hunter D.D, Brunken W.J. The Journal of Neuroscience, 2000
Here, they examine the expression of all known laminin chains within the retina. The interphotoreceptor matrix (and, during early development, the subretinal space) contains the laminin a3, a4, a5, b2, b3, g2, and g3 chains. This suggests the presence of three laminins: laminin-332, laminin-423, and laminin-523. These laminin isoforms could exert important effects on photoreceptor development and may play a role in photoreceptor production, stability and synaptic organization.
Molecular interactions in the retinal basement membrane system: A proteomic approach
Manimalha Balasubramani, Emanuel M Schreiber, Joseph Candiello, G K Balasubramani, Justin Kurtz, Willi Halfter. Matrix Biol, 2010
The authors describe a direct analysis of an in vivo basement membrane (BM) system using a mass spectrometry (MS) based proteomics approach. Nidogens-1 and -2, laminin subunits α1, α5, β2, and γ1, agrin, collagen XVIII, perlecan, FRAS1 and FREM2 were the most abundant BM protein components.
Identification of cell surface markers and establishment of monolayer differentiation to retinal pigment epithelial cells
Plaza Reyes A., Petrus-Reurer S. Padrell Sánchez S., Kumar P., Douagi I, Bartuma H., Aronsson M., Westman S., Lardner E., André H Falk A., Nandrot E.F., Kvanta A., Lanner F.Nature Communications, 2020
Here, the authors have performed a comprehensive antibody screening and identify cell surface markers for RPE cells. They identified CD140b, CD56, GD2, and CD184 as central cell surface markers to evaluate hPSC-RPE differentiation efficiency, as well as a potential tool for the enrichment of hPSC-RPE during and after differentiation. They show that these markers can be used to isolate RPE cells during in vitro differentiation and to track, quantify and improve differentiation efficiency. Using these markers together with single-cell RNA-sequencing to evaluate the differentiation process, they have established an efficient, robust, direct and scalable xeno-free and defined monolayer differentiation protocol, where culture on supportive human recombinant Biolaminin 111 and 521 eliminates the need for manual selection, allowing large-scale production of pure hPSC-RPE.
Generation of Retinal Pigment Epithelial Cells Derived from Human Embryonic Stem Cells Lacking Human Leukocyte Antigen Class I and II
Petrus-Reurer S. Winblad N., Kumar P., Gorchs L., Chrobok M., Kathleen Wagner A.K., Bartuma H., Lardner E., Aronsson M., Plaza Reye A., Andre H., Alici E., Kaipe H., Kvanta A., Lanner F.Stem Cell Reports, 2020
In this Stem Cell Reports article, the authors developed a strategy to evade the immune recognition triggered during transplants therapies with human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells. They generated and characterized hESCs and hESC-RPEs lacking surface presentation of HLA-I and -II through CRISPR/Cas9 targeting of B2M and CIITA. They established single-knockout beta-2 microglobulin (SKO-B2M), class II major histocompatibility complex transactivator (SKO-CIITA) and double-knockout (DKO) hESC lines that were further differentiated into corresponding hESC-RPE lines lacking either surface human leukocyte antigen class I (HLA-I) or HLA-II, or both. The activation of CD4+ and CD8+ T-cells was markedly lower by hESC-RPE DKO cells, while natural killer cell cytotoxic response was not increased. The results show that hESC-RPEs lacking HLA-I and -II evade T-cell response. Moreover, hESC-RPEs lacking HLA-I and -II do not increase NK cell cytotoxic activity. After transplantation of these immune-modified hESC-RPEs in a preclinical rabbit model, donor cell rejection was reduced and delayed. In conclusion, we have developed cell lines that lack both HLA-I and -II antigens, which evoke reduced T-cell responses in vitro together with reduced rejection in a large-eyed animal model. The results support the strategy to overcome host-donor mismatch in non-autologous cell-based treatment of AMD and other hESC-derived cell replacement therapies.
N-Terminomics identifies HtrA1 cleavage of thrombospondin-1 with generation of a proangiogenic fragment in the polarized retinal pigment epithelial cell model of age-related macular degeneration
Chen C-Y., Melo E., Jakob P., Friedlein A., Elsässer B., Goettig P., Kueppers V., Delobel F., Stucki C., Dunkley T., Fauser S., Schilling O., Iacone R. Matrix Biology, 2018
Here, the authors investigate the impact of elevated HtrA1 levels on the retinal pigment epithelial (RPE) secretome using a polarized culture system. The authors suggest a mechanism by which increased levels of HtrA1 may contribute to AMD pathogenesis. Human primary Retinal Pigmented Epithelium (RPE) cells (Sciencell, 6540) were seeded in transwells coated with Laminin 521. A model that recapitulates the structural, molecular and apical/basolateral signatures of adult RPE cells was achieved. The upregulation of HtrA1 alters the abundance of key proteins involved in angiogenesis and extracellular matrix remodeling. Thrombospondin-1, an angiogenesis modulator, was identified as a substrate for HtrA1 using terminal amine isotope labeling of substrates in conjunction with HtrA1 specificity profiling. HtrA1 cleavage of thrombospondin-1 was further corroborated by in vitro cleavage assays and targeted proteomics together with small-molecule inhibition of HtrA1. While thrombospondin-1 is anti-angiogenic, the proteolytically released N-terminal fragment promotes the formation of a tube-like structure by endothelial cells.
Xeno-Free and Defined Human Embryonic Stem Cell-Derived Retinal Pigment Epithelial Cells Functionally Integrate in a Large-Eyed Preclinical Model
Plaza Reyes A., Petrus-Reurer S., Antonsson L., Stenfelt S., Bartuma H., Panula S., Mader T., Douagi I., Andre H., Hovatta O., Lanner F., Kvanta A. Stem Cell Reports, 2015
This publication by the groups of Drs. Hovatta, Lanner, and Kvanta describe the production of hESC-RPE cells in a xeno-free and defined manner. In the paper, they describe an effective differentiation methodology using a human recombinant laminin-521 matrix with a xeno-free and defined medium. The differentiated RPE cells exhibit native characteristics including morphology, pigmentation, marker expression, monolayer integrity, polarization, and phagocytic activity. The authors also established a large-eyed geographic atrophy model that allowed in vivo imaging of the hESC-RPE and host retina. Cells were transplanted in suspension and showed long-term integration and formed polarized monolayers exhibiting phagocytic and photoreceptor rescue capacity.
Retinal Pigment Epithelial Cells Synthesize Laminins, Including Laminin 5, and Adhere to Them through a3- and a6-Containing Integrins
Aisenbrey S., Zhang M., Bacher D., Yee J., Brunken W.J., Hunter D.D.Invest Ophthalmol Vis Sci., 2006
The multilayered extracellular matrix underlying the retina is Bruch’s membrane (BM). Here they show that BM contains laminin chains that could form laminin-111, -332, -511, and -521. RPE cells synthesized these laminin chains in vitro, hence, RPE cells may synthesize BM laminins. The RPE cells adhered to the BM component collagen IV, but preferentially adhered to laminins. Of the laminins tested, the RPE cells adhered preferentially to laminin 332. The RPE cells interacted with these laminins via a3 and a6 containing integrins.
North Carolina Macular Dystrophy Is Caused by Dysregulation of the Retinal Transcription Factor PRDM13
Small K.W., DeLuca A.P, Whitmore S.S, Rosenberg T., Silva-Garcia R., Udar N., Puech b., Garcia C.A., Rice T.A., Fishman G.A, Héon E., Folk J.C, Streb L.M., Haas C.M., Wiley L.A., Scheetz T.E., Fingert J.H., Mullins R.F., Tucker B.A., Stone E.M.American Academy of Ophtalmology, 2015
Genome sequencing of patients to identified rare mutations involved in macular dystrophy. iPSCs were maintained in Essential 8 media on 521-To-Go plates and then differentiated by a 3D differentiation protocol to retinal tissues.