So now that the transplant is done, what’s happening.  In a word, Haematopoiesis.  It’s a Greek word formed from two other Greek words.  One meaning ‘blood’ the other meaning ‘to make’.  Making blood.

Using stem cells.  The ones that, as I type, are being introduced into Kristina.

Fun fact:  The healthy adult human makes between 10 billion and 100 billion new blood cells each day (no wonder I’m tired).  Take a nap.  You’ve earned it.

What sorcery is at play?  Stem cells.  Haematopoietic stem cells.  Or, as my spell checker likes, Hematopoietic stem cells.  These cells have the unique ability to give rise to all the different mature blood types and tissues.  Some that stay in the bone marrow, some that flow through the blood and others that in tissues. In laymens terms, the main ones are red blood cells, white blood cells, and the platelets.

But (of course) it’s more complicated than that.  Stem cells can create a wide variety of cells, but do so through another layer of cells called  ‘progenitor cells’.  The progenitor cells are only slightly less cool than stem cells.

Stem cells can live indefinitely and create progenitors, but progenitor cells can only create certain specific cell types and can only replicate so long before they expire.  As long as the stem cells are good, the creation of the progenitors and subsequent cell types can go on for a long time. 

So what type of cells do stem cells create?  They have big fancy words and different levels of creation.  Picture a big family tree with two diverse kids more diverse grandkids and great grandkids each with special powers all originating from a single parent (don’t dwell on that analogy too long).  But it’s fascinating how these stem cells organically know where to go (the spongy bone marrow) and how they replicate into myeloid progenitors and common lymphoid progenitors which in turn create another level and type of blood cells, some of which then give rise to still other types of blood cells. 

The progenitors mostly live in the factory – the bone marrow.  But the cells they create go forth and do the real work throughout the body, delivering oxygen and fighting off invaders.

And while we’re at it, let’s ponder for a bit just how new this process of transplanting stem cells is.   It started in the 1950’s, the decade into which I was born, right here in Seattle by the very hospital where Kristina is getting her transplant – the Fred Hutch Cancer Research Center (which is now just the Fred Hutch Cancer Center).

Dr. E. Donnall Thomas was the primary driver of treatments for blood cancers in the 60’s at the Fred Hutch and received the 1990 Nobel Prize in medicine for his ground breaking research.  Most of which was done right here in Seattle.

Fascinating process and Kristina’s in the right place at the right time in history.