What's involved in the stem cell collection process?

What's involved in the stem cell collection process? So patients need to get certain blood tests done, get their hearts and lungs checked out through echocardiograms and lung function tests to kind of meet the basic requirements of going through a stem cell transplant. Once they've gone through that process and we have a thumbs up from their respective insurance companies as well, there's generally a central line place, you know, it's usually an upper body central line, which will be utilized for the stem cell collection process. You know, in the old days of the bone marrow transplantation, we actually did go to the operating room and take a liter of your bone marrow. Then we would do the chemotherapy and give you back your bone marrow and we called it a bone marrow transplant. But actually now the correct terminology is a hematopoietic stem cell transplant. And the reason for that is that we learned that we don't need the entire bone marrow to restore your bone marrow. We actually just need the stem cells to live in your bone marrow. And so we've learned how to stimulate those cells in the bone marrow with these drugs called growth factors or granulite colony stimulating factors or GCSF, also called granics, also called nupogen. These cells will actually lead to the cells to divide and eventually leave the bone marrow. And that may be sufficient to actually then start collecting the cells. In many patients, if we want to collect especially for two transplants, often that's not sufficient. And we give a second drug called plurixaphor, which actually basically removes the anchor of the stem cells in the bone marrow and allows them to flow away into the blood. And so we're basically pushing the cells out into the bloodstream so that we can then collect them through the catheter and through the peripheral blood. So that actually depends on payer issues. It can be performed by the patient. It can be performed by a caregiver. It can be performed at a physician's office. And oftentimes this is related to reimbursements, whether or not the nupogen can be supplied to the patient directly or needs to be administered in a physician's office. When you have a certain sufficient number of CD34 cells in the bloodstream and you've made calculations that, all right, if the CD34 counts get to this number, I would be able to collect this many amount of stem cells. That's when you bring patients in to the aphoresis center and that central line is hooked up to an aphoresis machine, which functions very much like a hemodialysis machine. The actual collection process is performed on something called the phoresis machine, which is basically a machine where blood from the patient is removed. It's circulated through tubes without actually touching the machine, but through sterile tubes. Inside the machine, there's a centrifugation process where the white cells that contain the stem cell population are removed and the blood is returned back to the patient. Then that type of procedure typically takes three or four hours a day. And generally patients can collect sufficient stem cells anywhere between one and five consecutive days of this type of phoresis procedure. So the blood flows through that machine, the machine fluxes out the stem cells and stores them away in the bag. And then once that process is done, the stem cell processing lab processes those stem cells and freezes those bags for future use. And those stem cells can be used five, 10, 15, 20 years from now, given how the process is nowadays. Then we wait for another week or 10 days and patients are brought into either the hospital or in the outpatient setting to get high dose melphalan. And then a day later they get parts of their stem cells that have been collected back. That's how the whole process kind of flows. That is a very good question and that's something that you should ask. Normally there is a minimum number of stem cells that is required to restore your bone marrow function after a transplant. And that's usually about two million cells. Most of us like to give a little bit of a cushion in case not all of the cells are perfectly viable. So we tend to give at least three to five million cells. And that is for one transplant. Myeloma is the one disease where sometimes a second transplant is helpful, both immediately following the first transplant, they may call that tandem transplants, or perhaps in the future at a time of relapse. And so for the most part you should be collecting for at least two transplants. So when you are harvesting, as your blood is going through all this tubing and through the machine and the collection process, you will actually lose a lot of electrolytes, calcium and magnesium and potassium. And so the pharesis nurses will be replacing you to prevent you from having cramping and sort of tetany and all these uncomfortable things that you can experience because of the loss of those electrolytes. So Tums of course being giving you calcium back.