What Does Bone Marrow Actually Do?

We all have bone marrow but do we even need it? 

Yes. Very much yes. Hey, there are skeletons hiding inside sacks of meat, Jules here for DNews! I’m here to talk about bone marrow transplants, but we have to know what bone marrow is in the first place. In our bodies, there are these super cool types of cells called “stem cells”. We’ve talked about them before, but in a nutshell, these cells have the potential to turn into other types of cell that makes up the human body. One of the places we have stem cells is in our bone marrow. Bone marrow is a soft and fatty tissue that resides inside your bones and stores the stem cells that ultimately become blood cells. That’s red blood cells, which deliver oxygen throughout the body, white blood cells, which fight pathogens in your blood, like bacteria, and platelets which help clot up your blood 

when you get injured. 

But there are certain diseases that attack these cells, like multiple myeloma, which 

is cancer of the plasma cells, and leukemia, which causes abnormal white blood cells. To treat these diseases, doctors often first give patients high-dose chemotherapy or radiation treatments, which are intended to kill or disable most of the damaged, cancerous cells. But now, while patients may no longer have bad cells, they have very few good ones left either. That’s where the bone marrow transplant comes in; it is an effort to restart healthy cell production. There are three types of transplants: first, autologous, which means the marrow came from the patient’s own body and was extracted before chemo and radiation.

Another type is an allogeneic transplant, where all means “other” since another a the a 

person is donating their bone marrow. Problematically, the marrow has to come from someone with closely matching genes, like a relative. This is because most cells in your body have a particular protein marker telling your immune system that they belong to you. If the donor doesn’t have the same marker as you, your body might consider the new marrow an invader, and with effectively no immune cells left, that’s deathly dangerous. The last, and most controversial type of transplant, is an “umbilical cord blood” transplant. This is where stem cells are removed directly from a newborn child’s umbilical cord and placenta, and because the cells are so immature, they don’t need to be genetically identical the same way adult stem cells do. But despite the near-miraculous use of these stem cells to cure blood diseases, there is still one big barrier for many patients: access to healthy cells. For those who cannot use their own, there are Bone Marrow registries. There’s a stigma about how painful it is to donate, but according to the National Marrow Donor Program, bone marrow donation is usually a surgical outpatient procedure with anesthesia, with no pain during the extraction. Doctors use a needle to remove liquid marrow from your pelvic bone. Yes, I know this looks painful, but apparently, it typically isn’t. And don’t worry, it’s only about 1 to 5% of your marrow, and it’ll regenerate within just four to six weeks. However, the after-effects can include back or hip pain, fatigue, muscle pain, headache, and bruising at the incision site. On the receiving end, the cells from the donor marrow sample are inserted through a direct catheter line into the bloodstream. They find their way to the patient’s marrow and begin to make healthy blood cells. While more than 27 million people are registered as bone marrow donors, there are significant issues in getting bone marrow to certain ethnic groups with more diversity in their genetic line. People of European descent have less genetic diversity, and register in larger numbers, meaning that there are more matches to be made. Meanwhile, other ethnicities, such as African and Hispanic people tend to register less, and require more unique genetic matches. Today, bone marrow transplants save thousands of people each year, and just in the United States, roughly 20,000 such procedures are performed. But with as many as 70% of those needing a transplant unable to find a matching relative, bone marrow registration is more important than ever. Go out and get registered. Just like organ transplants, bone marrow transplants can fail if the donor and the recipient aren’t matched well. But what if there was a way to alter your immune system so that you could receive an organ from an incompatible donor?