Harvest


It's been a long and hard week in the world of Josh. Finally, the preparations to my 'special day' have officially begun and I've been harvested.


Yes, in this context my stem cells are like a crop. They were grown, monitored and harvested, all inside my beautiful bones. To kick start the extra production, I was self-injecting a drug called Neupogen (filgrastim) which is also referred to as G-CSF - Granulocyte Colony Stimulating Factor. It encourages the bone marrow to overproduce blood stem cells, which can then be extracted later. The overproduction is known to cause bone aches and pains. They sucked.

Quick stab in the belly and we're good.
Every evening for 10 days, I settled down with a hot Ribena and injected into my stomach. For many, I can imagine this to be their idea of a nightmare. I must admit, it wasn't particularly comfortable for me either. Sometimes you just have to close your eyes and get over it. The outcome will be worth it.

A blood test indicated when the level of stem cells was high enough. They use a special marker on the cells to detect how many are available. This marker is called haematopoietic progenitor CD34 antigen. Once the number exceeds the threshold, the time is right.

A real-life blood stem cell! Not mine though. That would be too cool.
This brings me to the actual process of harvesting. Technically speaking, the correct term is haematopoietic stem cell apheresis, although it's a bit of a mouthful and doesn't flow off the tongue. I'll stick with harvesting.

Removing the stem cells from the bloodstream has become a very simple procedure with the introduction of automatic machinery. The blood is removed from a vein in one arm, and sent through a centrifuge which separates out the blood cells by spinning them very fast. The machine identifies the different cells and removes the stem cells. The remaining blood is combined again, and returned through a vein in the other arm.

Meet Aphrodite, the apheresis centrifuge of love, pleasure and procreation.
I would love to be more technical, but the theory is very simple and effective. Unfortunately the simplicity of the process doesn't take away from how uncomfortable it is. The output needle must be very secure as the system works under high pressure. This means that the needle is metallic, fastened securely, and inserted under local anaesthetic. One arm must be kept perfectly straight and still for the entire duration of the harvest. The other uses a simple cannula which is made of flexible plastic.
My brave egghead.
Five hours after beginning, the machine stops. For safety's sake, they will not remove more than 120mL of blood/cells in one day. It takes the entire five hours to reach this volume. The cells, still warmish, are escorted to the laboratory and instantly analysed before being frozen. As like before, the technicians perform a CD34 count to verify the number of stem cells.
My stem cells, collected and bagged up. Vampires - hands off.
The total target of stem cells extracted depends on several factors - age, gender, height, weight, etc. For me, they wanted to harvest 2,000,000 cells/kg. This was expected to be easily obtained from two days on the apheresis machines.

After one day, only 700,000 cells/kg (35% of target) were extracted. Underwhelming, to say the least. Sometimes, the body needs a kick-start to release lots of stem cells at the right time.


This comes in the form of a drug called Mozobil (plerixafor) which cuts the microscopic anchors of the stem cells to release them. Great, huh? Except it meant more needles, a very sore injection site, and a common side effect, nausea. One dose also costs £5,860. It sounds expensive, although if somebody were to calculate my total medical costs over the past 18 months, you wouldn't even notice it.

One dose is equal to around 18% of my student loan.
Harvesting, day two, began again. Same process - needles in, arm straight, machine on. Five hours later, we were expecting a bumper crop! No. Only 700,000 cells/kg (35%) were extracted again. This is way below the target, and slightly below the minimum number that the hospital will risk a transplant with.
Day two, and feeling grumpy.
According to the nurses, almost nobody has to endure three days. My body wasn't cooperating, so day three was scheduled. Another dose of Mozobil was prescribed, and I returned to the hospital for the third day. Yet again, the same process as before. Five hours later, the CD34 count of the next harvest came back - 1,100,000 cells/kg!
Day three, and even grumpier. 
At last, the target was reached, plus a little extra. All the cells have been cryogenically frozen and are awaiting the time when I will need them.

The extra day of harvesting did mess up my beautiful planner from before. Stupid as it sounds, adding a day pushes my hospital admission date forward a week. It now is expected to be the 20th March, although it may shift if other factors don't go to plan.


Next appointments are coming through thick and fast though! On Tuesday 10th March, I have been referred to the Nuclear Medicine department to check heart and kidney functions. I'm not worried, and the 'nuclear' part of the name is just another way to say 'mildly radioactive dyes are used here'. Don't be scared.


More updates soon. In the meantime, keep checking back, and with some luck and determination, things will be over soon.
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Joshua Lerner

Hi! I’m the 'star' of Livin' With Lymphoma. The blog was founded on the 31st October 2013, on the day I was diagnosed with Stage 4B Hodgkin's lymphoma. I hope you find it funny and informative.

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