Abstract: Laminin and perlecan are key components of basement membranes, providing essential cues for stem cell maintenance and function. Laminin binds integrins to regulate cell survival, proliferation, and differentiation, while perlecan captures growth factors (GFs) via heparan sulfate (HS) chains attached to its N-terminal PDI domain, modulating GF availability to cell surface receptors. Given the cooperative signaling between integrins and GF receptors, a culture substrate integrating both laminin’s adhesive properties and perlecan’s GF-binding capacity is highly desirable. We engineered a recombinant laminin fragment conjugated with perlecan’s HS-rich PDI domain, termed PerLam. PerLam was produced in cGMP-banked CHO-S cells and purified via chromatographic steps. The purified protein carries HS chains and binds bFGF in an HS-dependent manner. When used as a coating, PerLam exhibits potent cell-adhesive activity and robustly supports human iPSC (hiPSC) proliferation. hiPSCs maintained on PerLam remain undifferentiated for over 10 passages. Notably, PerLam eliminates the need for precoating, as hiPSCs can be passaged directly onto fresh plates with PerLam-supplemented medium. Beyond expansion, PerLam promotes directed hiPSC differentiation into mesodermal lineages, including skeletal muscle progenitors, and enhances dopaminergic progenitor maturation in rodent Parkinson’s disease models. By combining laminin’s integrin-binding activity with perlecan’s HS chains, PerLam offers a promising next-generation culture substrate for hiPSC expansion and differentiation in regenerative medicine.
Funding Source: Supported in part by a grant from AMED (Japan Agency for Medical Research and Development; JP20bm0804025).
