In the 19th century, researchers were already postulating that blood was “produced” in the marrow1 and since 1932, researchers and doctors have pursued the possibility that marrow transplantation could significantly benefit patients with several blood borne diseases. The rationale is straight forward: if the marrow is where blood is produced, then transplanting it from donors to people who have a disease in the blood is very promising. The way to access the bone marrow from a donor is to use very hard needles that drill in specific bones (where we find more bone marrow substate), such the jelly tissue (the bone marrow), process it (not the point of this text) and then, infuse it directly in the blood of the patient. Fortunately, if successful, the cells find their way to the marrow and home inside the bone of the patient.
Surely, many conceptual roadblocks were yet unknown Investigators like the need to genetically match donor and recipient to increase chance of transplant success. Thanks to the work or many researchers like Donnall Thomas (Nobel Prize winner in 1990)2, little by little we got a better grip on the process of bone marrow transplantation. Little did they know then, but the jelly tissue being transplanted in patients was actually mix of hematopoietic stem cells that could give rise to an entire new blood system in the recipient, restoring its function.
This is a great example of how stem cell biology applied in real life is able to substantially improve the life of patients all around the world! Now, with much more knowledge available about stem cells, the main goal of the field is to bring more relevant therapies for patients. Today we still rely on bone marrow donors but in the future, we envision being able to produce these cells ex-vivo in very large quantities3. Exciting times!
- Cooper B. The origins of bone marrow as the seedbed of our blood: from antiquity to the time of Osler. Proc (Bayl Univ Med Cent). 2011 Apr;24(2):115-8. doi: 10.1080/08998280.2011.11928697. PMID: 21566758; PMCID: PMC3069519
- Henig I, Zuckerman T. Hematopoietic Stem Cell Transplantation—50 Years of Evolution and Future Perspectives. Rambam Maimonides Med J 2014;5 (4):e0028. doi:10.5041/RMMJ.10162
- Akhilesh Kumar, Saritha S. D’Souza, Abir S. Thakur, "Understanding the Journey of Human Hematopoietic Stem Cell Development", Stem Cells International, vol. 2019, Article ID 2141475, 13 pages, 2019. https://doi.org/10.1155/2019/2141475