Polymerized Laminin-521: A Feasible Substrate for Expanding Induced Pluripotent Stem Cells at a Low Protein Concentration

Abstract

Laminins (LNs) play a central role in the self-assembly and maintenance of basement membranes and are involved in critical interactions between cells and other extracellular matrix (ECM) proteins. Among the defined, xeno-free ECM culture matrices, LNs—namely LN521—have emerged as promising coating systems for the large-scale expansion of induced pluripotent stem cells (iPSCs). The biologic activity of LNs is enhanced by their acidification-induced self-polymerization into a cell-associated network called polylaminin (polyLN), which can recapitulate the native-like polymeric array in a cell-free system. Here, we show for the first time to our knowledge that polyLN521 displays a native-like hexagonal-like structure and that, at basal and low concentrations, it permits the large-scale expansion of human iPSCs. Human iPSCs expanded with polyLN521 maintained the pluripotent state and showed no impairment of karyotype stability or telomere length. These results suggest that low-concentration polyLN521 is a stable and cost-effective coating for large-scale iPSC expansion.

Laminin Alpha 2 Enhances the Protective Effect of Exosomes on Human iPSC-Derived Cardiomyocytes in an In Vitro Ischemia-Reoxygenation Model

“…For MSC-EXO production, we coated plates with polyLNs-the biomimetic form of human recombinant LN211 or LN221 (100 µg/mL, BioLamina, Sundbyberg, Sweden), (Supplemental Figure S4A). We diluted the polyLNs in cold, sterile acid buffer solution (20 mM sodium acetate, 1 mM CaCl 2 , pH 4.0) at final concentrations of 5 µg/mL (polyLN211 and polyLN221) as previously reported [55]. Then, 10 mL of polyLN211 or polyLN221 was added to a 175 mm 2 flask, which was maintained overnight at 37 • C. The next day, we washed the flasks 3 times with phosphate-buffered saline (PBS) before plating the cells.…”

Design of dual peptide-conjugated hydrogels for proliferation and differentiation of human pluripotent stem cells

“…Unlike conventional cells such as cancer cells or primary cells extracted from tissues, hPSCs cannot, in general, proliferate on conventional dishes made of polystyrene. hPSCs are extensively cultured on extracellular matrix (ECM) proteins, for example, in recombinant vitronectin (rVN)-coated or laminin 521 (LN521)-coated dishes [ [8] , [9] , [10] , [11] , [12] ]. Recently, peptide-conjugated materials have been prepared for hPSC proliferation by several researchers [ 8 , [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] , [21] , [22] , [23] , [24] , [25] , [26] , [27] , [28] ].…”