Why Cell Biology?
Our bodies are made of roughly 40 trillion tiny cells. These cells can be quite autonomous, but they mostly work together because they are connected by their surrounding membranes – vanishingly thin sheets that flattened out and stitched together would cover about twenty-four football fields*. These membranes are buzzing hubs, relaying signals that coordinate cells and exchanging vital nutrients and waste products so cells can stay healthy. They also serve as a platform to assemble minute scaffolds that give the cells their shape – and collectively, sculpt cells into the tissues and organs that make up our bodies.
What we do
We try to figure out how these cell membranes work. We use cutting edge genetic engineering approaches to probe and experiment on cell membranes. We watch these experiments unfurl in real-time in single, living cells viewed under extremely powerful microscopes.
Why we do it
Malfunctioning membranes are the basis for many of human diseases. For example, membranes that send signals telling cells to divide when they shouldn’t cause cancer. Bacteria and viruses trick cell membranes into swallowing them up, hiding them from the immune system. Muscle cells around blood vessels and airways sometimes relay signals from their membranes to contract more than they should, leading to diseases like hypertension and asthma.
By understanding in detail how membranes normally work, we aim to learn exactly what goes wrong in these and other diseases – and hopefully, figure out how new medicines can be developed to treat them.
*This is just a rough estimate, and could be wrong. But here’s some real references, so if it is wrong, I can blame someone else: 40 trillion cells is rounded from a recent best guess for a typical adult human [1]. Lets assume that these are about as big as a BHK cell – not an especially tiny or large animal cell – at 2000 square micron surface area for its membrane [2]. So, here’s the math: 4×10^13 x 2×10^-9 = 80,000 square meters. A Football field is roughly 3345 square meters (I know, I know – that should be in yards not meters but hey, you convert microns into yards!). So, that’s roughly 24 football fields, rounding up. Aficionados will argue that “Gerry, you’re not made of 40 trillion BHK cells” and that’s true – indeed, the cells in our bodies vary greatly in size [1] and even more so in surface area. So this is a very rough estimate. If I were a true champion of science I would use my own cells and measure it myself – but firstly, good luck removing, flattening and stitching together 40 trillion membranes and secondly, I surely wouldn’t survive the process. –GH.
[1] Bianconi, E., Piovesan, A., Facchin, F., Beraudi, A., Casadei, R., Frabetti, F., et al. (2013). An estimation of the number of cells in the human body. Annals of Human Biology, 40(6), 463–471. http://doi.org/10.3109/03014460.2013.807878
[2] Griffiths, G., Back, R., & Marsh, M. (1989). A quantitative analysis of the endocytic pathway in baby hamster kidney cells. The Journal of Cell Biology, 109(6 Pt 1), 2703–2720.
Hammond Lab 