Go, T-Cells!
Matthew Willey - 12th December 2022
At this very moment, there is a war going on in my body.
It is a war of unimaginable scale, with billions of participants. It is a war that has been going on, not just in my body but in the body of all my ancestors, since time immemorial.
If my side loses, I die. Indeed, the costs on both sides couldn’t be higher.
I have some reason to think my side will prevail. Every single one of my ancestors fought this war and won. I have had immunisations which have tipped the hand of the invaders to the defenders. If the war gets to a certain point, I can call in medical allies who are armed with antiretrovirals and oxygen.
But we are a long way from that, the war is still being waged internally.
It is a war filled with participants of mind boggling complexity. Machines and soldiers and weaponry are being cranked out for a war that relies on subterfuge, diversion, tactics, weight of numbers and murderous intent.
The battlefield that sends my temperature soaring and my heart pounding is too complex for one human to grasp. The immune system is a mountain of incomplete sciences that work together in a way that we do not fully comprehend.
My defences start at the skin, and that simple wrapping has kept me safe until now. No virus can penetrate the armour. But over the weekend, someone sneezed and I inhaled a droplet, or I touched my eyes, and a virus found itself into my sinuses.
This virus is evolution incarnate. Utterly without purpose, and ruthlessly effective. Over the weekend it invaded my mucous membranes (feel free to skip) and replicated in hundreds, then millions, then billions.
Forewarned, my adaptive immune response set about replicating this, literally, feverish growth. By Monday I noticed a slight sniffle, my only awareness of the beginnings of a calamitous onslaught. By Monday night it occurred to me to do a RAT test, and the situation dawned.
By that time, an armada of baffling complexity was swinging into action. Tipped off by my vaccinations, my adaptive immune response churned out lymphocytes, B-Cells, T-Cells and many other warriors and weapons. A system akin to military intelligence sent signals from the front lines to where vast hatcheries in my marrow turned out foot soldiers.
My army set to work engulfing, spearing, eating, tearing apart every virus particle it could find.
Because the virus hit the ground running, my adaptive immune system needed a few days to reach full strength. It is an armada of dazzling size and a ruthless destroyer. That it knows the difference, in the white heat of battle, between friend and foe is only one of its many miracles.
It’s day three, and I’m bouncing off the walls with a high temperature whilst I shakily make my way to the bathroom.
I have had plenty of time to think, and what occurs to me is the sheer alienness of viruses. We live in a world of purpose, of cause and effect. A virus does not. It has no intention to invade and maim and kill, yes it does so with breathtaking precision. It is evolution, pure and simple. Without human bodies, it would be extinct in hours.
To say that it has a purpose is equivalent to saying gravity wants to pull. We can’t understand something so tiny, so economically, so parsimoniously destructive, and yet for it to have no reason at all.
My immune system is the result of fighting wars like this, high stakes wars on an unimaginable scale, but for nothing. The only prize is survival.
I strongly recommend the Kurtgesagt book “Immune”. It shows a glimpse of the vast and underexplored wonder that is the immune system. And that’s where I do find meaning, in the microscopic immensity of it all, lying weakly in bed on a Wednesday night, at 38.5 degrees and falling.
Go, T-Cells. You got this. I’m sorry I gave you zero thought last week.