In vitro based systems
Introduction to in vitro based systems for studying basement membranes
Studies in vitro using purified or recombinant basement membrane fragments have provided huge insight into basement membrane protein structure and function and these were the original biochemical investigations that established the field of basement membrane research. As an extension of these studies, cell-based investigations allow for molecular pathways to be interrogated in a manner not feasible in animal studies. Cells are advantageous in their ability to be easily manipulated, such as being able to knock in/out genes of interest, as well as being able to insert fluorescent tags. Immortalised cell lines are cost effective, easy to use, provide an unlimited supply of material and bypass ethical concerns associated with animal models.
Cell lines from a variety of origins, including immortalised and primary, produce a complex network of matrix in culture. In vitro models have facilitated basement membrane-relevant discoveries.
In vitro studies have progressed from monoculture to coculture to organ-on-a-chip models. The use of bioreactors and chips to apply physiologically relevant flow has displayed further advances in these models, encouraging matrix deposition and formation of basement membrane-like structures. The Wyss Institute has been a pioneer in the field of developing organ-on-a-chip models and these are widely available for organs including but not limited to kidney, lung and brain.
Another advance in cell-based models has been the development of 3D tissues through stem cell culture. It is possible to culture small tissue structures, known as organoids, which harbor some of the key multicellular, anatomical and even functional hallmarks of real organs. In kidney organoids collagen IV networks are detectable and thus provide an alternative in vitro model in which basement membranes can be studied.
All in vitro models are somewhat limited in terms of their in vivo similarity and it is important to take this into consideration. Culture conditions may vary between labs and this can have an effect on protein expression/localization and morphology of the cells. However, due to the ease of setting up experiments and the other advantages mentioned, cells continue to be a useful tool to study basement membranes.
Labs with a focus on basement membrane research
Hudson Lab Type IV collagen, structure and function
Yurchenco Lab Laminins, structure and function
Lennon Lab Kidney basement membrane, disease
Van Agtmael Lab Basement membranes in disease
- Collagen IV and basement membrane at the evolutionary dawn of metazoan tissues. Fidler, AL et al. Elife. 2017 Apr 18. PMID: 28418331
- Chimeric protein repair of laminin polymerization ameliorates muscular dystrophy phenotype. McKee, KK et al. J Clin Invest. 2017 Mar 1. PMID: 28218617
- Glomerular cell cross-talk influences composition and assembly of extracellular matrix. Byron, A et al. J Am Soc Nephrol. 2014 May. PMID: 24436469
- Kidney organoids from human iPS cells contain multiple lineages and model human nephrogenesis. Takasato, M et al. Nature. 2016 Aug 11. PMID: 27120161
- 3D organoid-derived human glomeruli for personalised podocyte disease modelling and drug screening. Hale, LJ et al. Nat Commun. 2018 Dec 4. PMID: 30514835