I feel fortunate in my research because I don’t use an animal model. Most labs doing what I do use mice or rats for their research. We do so very sparingly, prefering to use a “stripped down” cell culture system, at least for our initial research. Animal work only arrives at the end of a project to provide proof of principle.

HEK cells. Thanks to The University of Hull

The cell culture system we use employs a type of cell known as HEK, short for Human Embryonic Kidney. It is, as its name more than suggests, a cell line harvested from the kidney of a human embryo. This harvesting took place decades ago, long before thoughts of patient consent were considered (Just ask Henrietta Lacks about that one). The cells are essentially just epithelial cells, the simple cells that form the linings of your mucous membranes. We can take these cells and “transfect’ them with the DNA coding for the proteins we’re interested in studying. To translate that, basically we infect the cell with DNA. A few days later the cell has made use of this DNA because it can’t tell the difference between the new we gave it, and its own. Because of this the cell is making the proteins we study.

I study a cellular process known as signal transduction. This is the study of how a cell (in my case, a brain cell or neuron) correctly interprets and responds to the signals it receives from its environment. Neurons are hellishly complicated cells and it is a real challenge to dissect the molecular pathways used for signal transduction.

That’s where our HEK cells come in handy. We can essentially recreate a simplified neuron by selecting a few cellular components that we wish to study and making the HEK express them. I can make it express glutamate receptors (see my first post), and it will do so quite happily. And these receptors will function almost exactly as they do in your brain.

It’s wicked good fun!

Now, how can we be using something that was harvested decades ago? Well, they live in little plastic dishes quite happily, ut to keep the cells healthy and fit they must be “passaged” every few days. This means you wash them, give them fresh food-media (a sort of broth), and re-divide them. Around the world there are companies who maintain pure lines of cells. They’re generally stored in liquid nitrogen, a shockingly cold -190C, which effectively keeps them in stasis, eternally trapped in youth.

We order our cells at passage (P) 35 or 36. We use them for a maximum of 8 passages, so they get discarded at around P43. To keep the work in the lab rolling along, for time and science wait for no man, we have to defrost a new batch of cells around the time we reach P41.

Now my boss just had a birthday…you guessed it, his 41st. We celebrated in a way traditional to Western Gentlemen since the dawn of the brewing age.

Needless-to-say the day after the night before was painful. To quote Withnail, “I feel like a pig has shit in my head.”

Or, to quote a friend of mine who lived and worked in Japan and made the mistake once of drinking with his Salarayman friends, “I just wanted to find a hacksaw and cut my own head off to make the pain go away.”

Not much science was done that day, but my boss made one pertinent observation that made me feel a little better.

He pointed out that if he was an HEK cell, at P41 we’d be getting ready to thaw out new talent, and in two passages time he’d be in the biohazard trash. I was able to point out that since I just turned 33, in two passages time I’ll be at P35 and ready to take the reins, as it were.

This (sad and geeky) analogy pleased me greatly. My boss, not so much. For me, it’s another reminder about postdoctoral life. Although it sometimes seems like you’re stuck in stasis, endlessly waiting, just another few months, just another year, just another publication, just another experiment, your time will come.

The important question is not necessarily when will that happen, but will I be ready when it does?