Publications
Here is a selection of publications where different laminin isoforms were used to create more authentic cell culture systems.
Blockade of 1 Integrin–Laminin-5 Interaction Affects Spreading and Insulin Secretion of Rat Beta-Cells Attached on Extracellular Matrix
Parnaud G., Hammar E., Rouiller D.G., Armanet M., Halban P.A., Bosco D.Diabetes, 2006
In this study, the authors show that outside-in signaling via engagement of B1 integrins by laminin-332 is an important component of normal B-cell function. By using specific blocking antibodies, the authors demonstrated that laminin-332 is the component present in 804G matrix (rat bladder carcinoma cell line), responsible for the effect of 804G matrix on B-cell function and spreading. Only the B1 integrin was detected in B-cells, a well-known laminin-332 ligand. Anti–B1 integrin antibody reduced the spreading of B-cells on 804G matrix. The blockade of the interaction between B1 integrins and laminin-332 resulted in a reduction in glucose-stimulated insulin secretion. Blocking anti–B1 integrin antibody also inhibited focal adhesion kinase phosphorylation induced by 804G matrix. In conclusion, anti–B1 integrin and –laminin-332 antibodies interfere with the spreading of B-cells, resulting in decreased insulin secretion in response to glucose.
Regulated laminin-332 expression in human islets of Langerhans
Armanet M., Wojtusciszyn A., Morel P., Parnaud G., Rousselle P., Sinigaglia C., Berney T., Bosco D.The FASEB Journal, 2009
In this article, the authors show that LN-332 is expressed in isolated human islets with labeling confined to endocrine cells. Labeling in isolated islets is granular but don’t colocalize with hormone secretory granules. LN- 332 is most abundant in cultured islets compared to freshly isolated islets and is found in a culture medium, which suggests that it is secreted by islets. When islets are exposed to interleukin (IL)-1B, expression and secretion of LN-332 increase compared to control. Inhibition of phosphatidylinositol 3-kinase (PI3-K) activity, inhibited culture and IL-1B-induced LN-332 expression in islets. These results show that LN-332, known to have some beneficial effect on B-cells in vitro, is produced and secreted by endocrine islet cells and is up-regulated by stress conditions such as culture and IL-1-exposure. Altogether, their observations can be considered as prerequisites necessary to hypothesize that the in vitro effect of LN-332 on B-cell secretion, viability, and replication is of physiological relevance as well.
Human Laminin Isotype Coating for Creating Islet Cell Sheets
Yamashita S., Ohashi K., Utoh R., Okano T., Yamamoto M.Cell Medicine, 2015
This study describes an experimental approach to create a monolayered islet cell construct (islet cell sheet), followed by transplantation into a subcutaneous pocket. The authors try to identify an optimal human ECM as a coating material on PIPAAm surfaces, which allowed rat islet cells to attach on the surfaces and subsequently to be harvested as a monolithic cell sheet. Dispersed rat islet cells were seeded onto PIPAAm dishes coated with various human laminin isotypes: LN211, LN332, LN411, LN511, and HL-placenta. The highest value of plating efficiency was found in the HL-332-PIPAAm group (83.1 ± 0.7%). The HL-332-PIPAAm group also showed the highest cellular confluency (98.6 ± 0.5%). Islet cells cultured on the HL-332-PIPAAm surfaces showed a positive response in the glucose-stimulated insulin secretion test. LN511 also showed good results.
Co-culture with extracellular matrix proteins reduces hypoxia-induced human islet cell death
Brandhorst et al. Xenotransplantation, Abstracts of the IPITA-IXA-CTS 2015 Joint Congress November 15–19, 2015, Melbourne, Australia
Islets are experiencing hypoxic conditions after transplantation. The aim of this study was to assess the effect of collagen IV and laminin isoform -521, -511 and -411 on the survival and function of isolated human islets exposed to severe hypoxia. Compared with hypoxic controls (100%) all ECMs significantly increased islet recovery after culture at 0.75% oxygen ranging from 163 +/- 12% to 173 +/- 28% using collagen IV or laminin-411, respectively. Increased post-culture recovery correlated with decreased islet fragmentation which was lowest using laminin-521 (66%, P < 0.01) and laminin-511 (66% P < 0.05). Islet ROS generation was also lowest after culture with laminin-521 and laminin-511. Islet viability was increased in all experimental groups when compared to controls but was highest using collagen IV and laminin-511. This observation corresponds to the insulin response after glucose challenge that was best preserved when collagen IV or laminin-511 was used for islet incubation.
The Vascular Basement Membrane: A Niche for Insulin Gene Expression and B Cell Proliferation
Nikolova G., Jabs N., Konstantinova I., Domogatskaya A., Tryggvason K., Sorokin L., Fässler R., Gu G., Gerber H-P., Ferrara N., Melton D.A., Lammert E.Developmental Cell, 2006
Mouse pancreatic islets intimately interact with endothelial cells and differentiation and delamination of insulin-producing b cells from pancreatic epithelium strictly require endothelial cells. Doug Melton and colleagues show that BMs within islets are formed and found exclusively around capillaries but not islet cells. Islet endothelial cells express laminin a4 and a5. Laminins promote insulin gene expression and proliferation in B-cells and B1-integrin is required for this laminin response. Laminin-411 and -511 worked well but also laminin-111 which shows that the applied laminin does not necessarily have to be endothelial cell-derived. Research on islet transplantation has shown that it takes about 1–2 weeks for transplanted islets to become revascularized in the host and the authors suggest that treating islets with these laminins prior to transplantation will help maintain insulin production until new capillaries are formed in transplanted islets.
Laminin 411 acts as a potent inducer of umbilical cord mesenchymal stem cell differentiation into insulin-producing cells
Qu H., Liu X., Ni Y., Jiang Y., Feng X., Xiao J., Guo Y., Kong D., Li A., Li X., Zhuang X., Wang Z., Wang Y., Chang Y., Chen S., Kong F., Zhang X., Zhao S., Sun Y., Xu D., Wang D., Zheng C. Journal of Translational Medicine, 2014
Efficient induction of differentiation to insulin-producing cells from MSCs. Up-regulated insulin expression at both mRNA and protein levels. Administration of the insulin-producing cells in T1 diabetes rats rapidly 1) down-regulated fasting blood glucose levels, 2) significantly reduced the HbA1c concentration and 3) markedly improved the symptoms and survival of the rats.
Key matrix proteins within the pancreatic islet basement membrane are differentially digested during human islet isolation
Cross S.E., Vaughan R.H., Willcox A.J., McBride A.J., Abraham A.A., Han B., Johnson J.D., Maillard E., Bateman P.A., Ramracheya R.D., Rorsman P., Kadler K.E., Dunne M.J., Hughes S.J., Johnson P.R.V.Am J Transplant. 2016
Here the authors investigated the impact of islet isolation on basement membrane (BM) integrity in the human islet. Collagen IV, panlaminin, perlecan and laminin-α5 in the islet BM were significantly digested by enzyme treatment. Laminin-α5 (found in both layers of the duplex BM) and perlecan were lost entirely, with no restoration evident during culture. Islet function and survival decreased and islet cytotoxicity increased during culture. The islet basement membrane (BM) influences islet function and survival and an incomplete islet BM has implications for islet integrity and transplanted graft longevity.
Culturing functional pancreatic islets on α5-laminins and curative transplantation to diabetic mice
Sigmundsson K., Ojala J.R.M., Öhman M.K. Österholm A-M., Moreno-Moral A., Domogatskaya A., Yen Chong L., Sun Y., Chai X., Steele J.A.M, George B., Patarroyo M., Nilsson A-S., Rodin S., Ghosh S., Stevens M.M., Petretto E., Tryggvason K. Matrix Biology, 2018
Here, the authors have developed a novel method to grow and maintain normoxic and functional islets which may significantly enhance the efficacy of islet transplantation treatment for diabetes. A key component of this method is the coating with biologically relevant laminins, found in the peri-islet capsule and BM of islet capillaries. Islets cultured in vitro on α5-laminins adhere and spread to form layers of 1-3 cells in thickness while maintaining cell-to-cell contacts. The cells remained normoxic and functional for at least 7 days in culture. In contrast, spherical islets kept in suspension developed hypoxia and central necrosis within 16 hours. Mouse islets plated on laminin-521 could be cultured in a serum-free mTeSR1 medium for an extended period of time. Approximately 20% of islet cells showed a co-expression of insulin and glucagon. The double-hormone expression was confirmed in histological analyses of mouse and monkey pancreata. The flattened islets start robust cell proliferation after a lag period of approximately two weeks in a serum-free mTeSR1 culture on laminin-521. Transplantation mouse islets cultured on α5-laminin-coated polydimethylsiloxane membranes for 3–7 days normalized blood glucose already within 3 days in mice with streptozotocin-induced diabetes.
Remodeling of the extracellular matrix is a requirement for the hepatic progenitor cell response
Kallis Y.N., Robson A.J., Fallowfield J.A., Thomas H.C., Alison M.R., Wright N.A., Goldin R.D., Iredale J.P., Forbes S.J.Gut, 2011
In advanced liver damage, hepatic regeneration can occur through the proliferation of a resident hepatic progenitor cell (HPC) population. Extra-cellular matrix (ECM) laminin invariably surrounds HPCs, but the functional requirement of this matrix-cell association is untested in vivo. Here, the authors test the relationship between collagen degradation, laminin deposition, and the HPC response. Failure of ECM remodeling after chronic fibrotic liver injury hinders the ability of the liver to activate HPCs. Laminin-progenitor cell interactions within the HPC niche are critical for HPC mediated regeneration.
Laminin 411 and 511 promote the cholangiocyte differentiation of human induced pluripotent stem cells
Takayama K., Mitani S., Nagamoto Y., Sakurai F., Tachibana M., Taniguchi Y., Sekiguchi K., Mizuguchi H. Biochem Biophys Res Commun. 2016
Here the authors searched for a suitable extracellular matrix to promote cholangiocyte differentiation from human iPS cells and found that both laminin 411 and laminin 511 were suitable for this purpose. Differentiated human iPSC to cholangiocyte-like cells via hepatoblasts-like cells (derived according to previous papers). The hepatoblast-like cells were mixed in a collagen gel and plated and for cholangiocyte differentiation, laminin was added to the medium. The gene expression levels of the cholangiocyte markers, aquaporin 1 (AQP1), SRY-box 9 (SOX9), cystic fibrosis transmembrane conductance regulator (CFTR), G protein-coupled bile acid receptor 1 (GPBAR1), Jagged 1 (JAG1), secretin receptor (SCTR), and g-glutamyl transferase (GGT1) were increased by using laminin 411 or laminin 511 as a matrix. In addition, the percentage of AQP1-positive cells was increased from 61.8% to 92.5% by using laminin 411 or laminin 511. Furthermore, the diameter and number of cysts consisted of cholangiocyte-like cells were increased when using either matrix.