Recent news on Thalassemia stem cell therapy -published in journal Nature Biotechnology- from a joint collaboration effort between New York's Sloan Kettering Cancer Center and Palermo's Cervello Hospital. This is great news and means a lot to those who are aware that they are carriers of the thalassemia gene.
Thalassemia beta major is a genetic condition
Thalassemia beta major babies when first born do not exhibit the symptoms of severe thalassemia as the baby has a special type of fetal hemoglobin known as Hb F. It has alpha chains and gamma chains but no defective beta chains (hence the name beta thalassemia major). However, as its hemoglobin converts to adult beta chains, the condition becomes noticeable as the child is anemic, requiring blood transfusions with all its related complications (see this chart on the problems associated with beta thalassemia)
How might the Trojan horse therapy work?
More on the basis of the stem cell therapy is available in this article but it essentially describes the virus carrying a healthy gene to replace the defective one in a thalassemia major patient's stem cells. This results increased levels of hemoglobin and converting the patient symptomatically and somatically into a thalassemia minor (compatible with normal life).
What about the next generation?
I'm not sure if the Trojan horse will also affect the germline cells, as only the bone marrow stem cells are extracted and exposed to the virus... meaning that children of these treated patients may still have a significant chance of inheriting 2 defective beta genes (one defective gene from each parent) and result in a thalassemia major child as well. However, if this technology is safe, can be easily replicated and commercially viable, it is a more elegant way of treating the condition vis-a-vis a stem cell transplant (which has its own risks).
Human trials with the Trojan horse stem cell therapy are due to start in the next few months. The article estimates that 3 million people worldwide are afflicted with this genetic condition and 50,000 succumb to the disease every year.
Prevalence and treatment in South East Asia
Apart from Singapore, which has managed to eradicate almost all cases of thalassemia major by pro-active screening and a strict genetic diagnosis program, in Malaysia and Thailand, thalassemia major is quite prevalent and many families especially in east Malaysia are not properly diagnosed nor chelation therapy administered due to costs associated with the desferrioxamine drug. Stem cell transplants only happen if there is a matched sibling source (bone marrow / umbilical cord blood / peripheral blood stem cells), a unit / donor which can be purchased from international banks; and if the child is still fit to undergo the procedure.
Stem cell transplantation for Thalassemia major by StemLife
Whilst on the topic of thalassemia major, StemLife has released a unit of cord blood stem cells for a sibling thalassemia major transplantation in the first quarter of this year and I'm happy to share that the child has since returned home. I'll share more updates with you when I have consent to release the details ;).
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