​What are Transwells and Why Use Them?

​What are Transwells and Why Use Them?

Transwell systems are a novel way of creating dual surfaces in a culture to study cell migration and sidedness. 

They also provide an attractive way to co-culture cells and study interactions while condensing time and the number of steps involved.

If it ain’t broke, don’t fix it… but sometimes conventional is short of best.

Pictured above 12 well plate with Transwell inserts, 48/case

In many ways, this makes them superior to spheroid and organoid cultures which take individual cells out of context from surfaces.

Apical vs. Basolateral Differences in Cultures

One of the challenges of studying polar cells in culture is the lack of comparable research models.

Cells that form membranes in some tissues have strictly defined apical and basolateral surfaces because of the adhesion proteins on each face.

Kidney glomeruli and the intestinal lining are polarized this way. 2D culture models obscure the basolateral surface and prevent the study of important in vivo differences.

The basolateral surface is the face in contact with the extracellular matrix, the network of proteins that holds the inner face of epithelial membranes in space.

Growth of cells within Transwell inserts allows the orientation to be taken into account when final results are gathered.

Cells can be stained and visualized within the inserts without disturbance, offering a unique perspective on polarized cell behavior.

Materials and Design Features

PET VS Other Plastics

Polyethylene terephthalate (PET) and Polystyrene are both prime growing surfaces for adherent cells, but PET is touted as one of the most translucent plastics and has better resistance to environmental factors.

Polycarbonate is the more durable alternative to the two, but it does not always provide ideal visualization conditions.

See our PET inserts here, or browse our durable polycarbonate inserts.

Matrigel Addition

Matrigel is the name for the artificial extracellular matrix that is sometimes used with Transwell inserts.

It is made from mouse tumor tissue and supplied as a serum.

Chemical Gradients

For cell migration assays, a migration buffer using culture media and a chemoattractant is used to produce ideal migration conditions for the cell type in question.

This migration assay protocol using complement protein is one common format used.

The general concept guiding this protocol is that media containing chemoattractants can be produced using a culture of cells from adjacent tissues.

An idea so simple you are probably surprised you didn’t think of it first.

Cell Signaling

In vivo cells receive chemical signals from the extracellular matrix that direct the movement of integrin proteins to the correct surface of the cell.

Transwells are designed to help researchers create lifelike chemical gradients that direct the migration of cells. This allows for easy study of monolayer cultures.

It’s easier than you thought to study membranes. Organoid and spheroid models are unlikely to compare!

Research Connections Using Transwells:

A study using human gut epithelium developed monolayer cultures from postmortem ileum punches and grew them in Transwells using Matrigel for several days.

These were tested for cytokines and gene expression, then sections of matrigel were removed for full visualization of surface differences.

Example Applications of Transwells in Current Research

  • Blood-Brain Barrier Research
  • Placental Research
  • Kidney Research
  • Gut Epithelial Research
  • And more…!

Thinking of what to do next with your epithelial tissue research? See what we can offer you today.

Discover Our Entire Selection of Transwell Inserts

Stellar Scientific is a small, family owned business that carries hundreds of supplies to fit your needs. We take pride in our ability to cater directly to our customers.

That’s why we aim to stay on top of all the most current advances in cell culture research.

Come see our selection of cell culture plate inserts, available in 6 well, 12 well, and 24 well formats.

If you would ever like to ask a question about a product, or i to make a suggestion about what we should carry, just reach out to us through the contact us page.



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  2. Lee, J. L., & Streuli, C. H. (2014). Integrins and epithelial cell polarity. Journal of cell science, 127(Pt 15), 3217–3225. www.acmeplastics.com/content/the-difference-betwe...
  3. Warner, Rodney. “PE vs. Pet: How Are They Different?” TDI Packsys, 12 June 2023, www.acmeplastics.com/content/the-difference-betwe...
  4. Wright, C.W., Li, N., Shaffer, L. et al. Establishment of a 96-well transwell system using primary human gut organoids to capture multiple quantitative pathway readouts. Sci Rep 13, 16357 (2023). www.acmeplastics.com/content/the-difference-betwe...