Posted by Becky
Today's topic is what's happening in Leif's bone marrow right now, and what that means for his future treatment.
The doctors say that the blood Leif has at the moment is being made by both his own and the donor's stem cells. Over the 100 days post-transplant, they will be checking Leif's level of chimerism, meaning the ratio of new to old cells in his bone marrow. The goal is for Leif to have more than 95% donor cells by Day 100. If he has 100% donor cells, he'll have complete chimerism. If he has some percentage of his own and some of the donor's he'll have mixed chimerism. If he has all his own cells, that's a graft failure and we hope that doesn't happen. The term "chimerism" comes from a Greek mythological creature with the wings of an eagle and the heads of a lion, a goat, and a dragon. In genetics, a chimera is an animal that has different DNA in some of its cells than in others. Some male tortoiseshell cats are chimeras, and so are stem cell transplant recipients.
Leif's stem cells were beaten up by the chemotherapy and radiation, and the donor cells weren't. That should give the donor cells an advantage, as they duke it out for territory inside Leif's bones.
The doctors can test for chimerism via blood test or bone marrow biopsy. Leif will be getting bone marrow biopsies, to check for both chimerism and lymphoma. As Leif describes it, although the cancerous B-lymphocytes have been cleared out of his body, the factories - his stem cells - are still there. We want those to be replaced by the donor's healthy stem cells. The doctors have a number of ways of adjusting his treatment, to achieve the goal of complete chimerism.
Leif's been sleeping a lot (about 18-20 hours per day) since he got home, which is expected. He's been waking up to take his pills, shower, go for his all-important daily walk, and eat. Today we went for a drive; I went to the office supply store, grocery store, and L.L. Bean, and Leif stayed in the car and looked at the great outdoors. He should not go out in public for quite some time yet, except for his necessary hospital visits. We got him some new warm gloves; the circulation in his hands isn't what it used to be, and his hands have been getting really cold on his walks.
He has more energy today than he had yesterday, and we hope that trend will continue. As his energy increases, I expect him to become stir-crazy. One of the problems with being immune suppressed is that you can't feel it, the way you can feel being sick. It's hard to believe you should not be out and about, increasing your exposure to pathogens, when you basically feel fine. So one of my jobs is to keep Leif reined in a little bit. Wish me luck!
Today's topic is what's happening in Leif's bone marrow right now, and what that means for his future treatment.
The doctors say that the blood Leif has at the moment is being made by both his own and the donor's stem cells. Over the 100 days post-transplant, they will be checking Leif's level of chimerism, meaning the ratio of new to old cells in his bone marrow. The goal is for Leif to have more than 95% donor cells by Day 100. If he has 100% donor cells, he'll have complete chimerism. If he has some percentage of his own and some of the donor's he'll have mixed chimerism. If he has all his own cells, that's a graft failure and we hope that doesn't happen. The term "chimerism" comes from a Greek mythological creature with the wings of an eagle and the heads of a lion, a goat, and a dragon. In genetics, a chimera is an animal that has different DNA in some of its cells than in others. Some male tortoiseshell cats are chimeras, and so are stem cell transplant recipients.
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| We do not expect Leif to look like this, regardless of his level of chimerism. |
Leif's stem cells were beaten up by the chemotherapy and radiation, and the donor cells weren't. That should give the donor cells an advantage, as they duke it out for territory inside Leif's bones.
The doctors can test for chimerism via blood test or bone marrow biopsy. Leif will be getting bone marrow biopsies, to check for both chimerism and lymphoma. As Leif describes it, although the cancerous B-lymphocytes have been cleared out of his body, the factories - his stem cells - are still there. We want those to be replaced by the donor's healthy stem cells. The doctors have a number of ways of adjusting his treatment, to achieve the goal of complete chimerism.
Leif's been sleeping a lot (about 18-20 hours per day) since he got home, which is expected. He's been waking up to take his pills, shower, go for his all-important daily walk, and eat. Today we went for a drive; I went to the office supply store, grocery store, and L.L. Bean, and Leif stayed in the car and looked at the great outdoors. He should not go out in public for quite some time yet, except for his necessary hospital visits. We got him some new warm gloves; the circulation in his hands isn't what it used to be, and his hands have been getting really cold on his walks.
He has more energy today than he had yesterday, and we hope that trend will continue. As his energy increases, I expect him to become stir-crazy. One of the problems with being immune suppressed is that you can't feel it, the way you can feel being sick. It's hard to believe you should not be out and about, increasing your exposure to pathogens, when you basically feel fine. So one of my jobs is to keep Leif reined in a little bit. Wish me luck!
Good luck, Becky (with keeping Leif reined in)!
ReplyDeleteGood luck, Leif, with all your healing work!!
Much love to you both!