Human Placenta Laminin-111 as a Multifunctional Protein for Tissue Engineering and Regenerative Medicine

Preparation of a universally usable, animal product free, defined medium for 2D and 3D culturing of normal and cancer cells

Since 1958, cell culture media supplemented with fetal bovine serum is used, despite the well-known concerns about animal welfare, reproducibility, reliability, relevance, and safety. To obliterate these concerns and increase scientific accuracy, we recently published an open access, publicly available paper on a defined medium composition to make it possible for any lab to prepare this medium. The medium supports routine culturing and cell banking as well as investigations of growth curves, dose response testing of compounds of cells in 2D and 3D, and cell migration; all important aspects for research and toxicology. Here we give a detailed description of how to mix the defined universal cell culture medium in 14 simple steps to support any entity that wishes to make it. We also list different normal and cancer cell lines that have been cultured in the defined medium.•Open source composition of animal product free universal cell culture medium•Protocols for mixing solutions of small xeno free molecules for supplementation•Protocols for mixing solutions of human proteins for supplementation.

A fast and efficient method for isolating Schwann cells from sciatic nerves of neonatal mice

BACKGROUND

Schwann cells (SCs) isolation is one of the basic techniques for study of peripheral nervous system and peripheral neuropathy. A combined and effective method of isolating SCs from sciatic nerves of newborn mice with high yield and purity is still lacking.

NEW METHODS

Sciatic nerves from neonatal mice aged 3-5 days serve as the source of SCs. Removal of adjacent connective tissue and epineurium, treatment with arabinoside hydrochloride and differential cell detachment technique were applied to eliminate fibroblast contamination and increase the purity of SCs. Combined use of collagenase/dispase and trypsin was chosen to increase the yield of SCs. Culture dishes precoated with poly-l-lysine and laminin, culture medium supplemented with heregulin β-1 and forskolin, and reasonable cell seeding density were implemented to increase the growth and proliferation of cultured SCs. Immunostaining of S100β and p75 neurotrophin receptor was used to identify the purity of SCs.

RESULTS

Our method is able to obtain high-yield SCs with a purity of 90% within five days and a purity more than 99% within seven days from sciatic nerves of neonatal mice.

COMPARISON WITH EXISTING METHODS

Previous SCs isolation mostly focused on rats or adult mice and have a few limitations due to fibroblasts contamination, low yield and time-consuming. Our method permits SCs isolation from neonatal mice with a high yield and purity of primary SCs within 7 days.

CONCLUSION

We described a fast, efficient and step-by-step method of isolating SCs from sciatic nerves of neonatal mice with high yield and purity.

An engineered CD81-based combinatorial library for selecting recombinant binders to cell surface proteins: Laminin binding CD81 enhances cellular uptake of extracellular vesicles

The research of extracellular vesicles (EVs) has boomed in the last decade, with the promise of them functioning as target-directed drug delivery vehicles, able to modulate proliferation, migration, differentiation, and other properties of the recipient cell that are vital for health of the host organism. To enhance the ability of their targeted delivery, we employed an intrinsically overrepresented protein, CD81, to serve for recognition of the desired target antigen. Yeast libraries displaying mutant variants of the large extracellular loop of CD81 have been selected for binders to human placental laminin as an example target. Their specific interaction with laminin was confirmed in a mammalian display system. Derived sequences were reformatted to full-length CD81 and expressed in EVs produced by HeLa cells. These EVs were examined for the presence of the recombinant protein and were shown to exhibit an enhanced uptake into laminin-secreting mammalian cell lines. For the best candidate, the specificity of antigen interaction was demonstrated with a competition experiment. To our knowledge, this is the first example of harnessing an EV membrane protein as mediator of de novo target antigen recognition via in vitro molecular evolution, opening horizons to a broad range of applications in various therapeutic settings.

Laminins Regulate Placentation and Pre-eclampsia: Focus on Trophoblasts and Endothelial Cells

Pre-eclampsia is a systemic vascular disease characterized by new-onset hypertension and/or proteinuria at ≥20 weeks of gestation and leads to high rates of maternal and perinatal morbidity and mortality. Despite the incomplete understanding of pre-eclampsia pathophysiology, it is accepted that insufficient spiral artery remodeling and endothelial dysfunction are major contributors. Laminins (LNs) are a vital family of extracellular matrix (ECM) molecules present in basement membranes that provide unique spatial and molecular information to regulate implantation and placentation. LNs interact with cell surface receptors to trigger intracellular signals that affect cellular behavior. This mini-review summarizes the role of LNs in placental development during normal pregnancy. Moreover, it describes how LN deficiency can lead to the pre-eclampsia, which is associated with trophoblast and vascular endothelial dysfunction. New research directions and the prospect of clinical diagnosis of LN deficiency are discussed, and the gaps in basic and clinical research in this field are highlighted.