- Laura Plitt
- BBC World News
When Sarah was barely 10 days old, her mother Maria-Luiza Prioteasa began to notice that something was wrong with her daughter.
“He vomited a lot, he did not gain weight, he had diarrhea, the diaper irritated his skin until it left it bleeding,” he recalls.
“As I am very thin and I do not eat very healthy I thought that my milk was not good enough. So I tried feeding it for a week half with my milk and the rest with formula milk,” he continues.
But the attempts of this mother from South Yorkshire, in the center of the United Kingdom, did not give the results she expected: the baby continued to lose weight.
After five weeks where Sarah’s diet and several blood tests were closely monitored, the doctors came to a diagnosis: the little girl had the severe combined immunodeficiency syndrome due to adenosine deaminase deficiency (better known by its acronym in English, ADA-SCID), a rare genetic disorder that leaves the sufferer without weapons to fight any kind of infection.
Bubble boy disease
The acronym SCID encompasses a group of genetic disorders that affect the development of the immune system.
There are several types of SCID, which vary depending on the protein or gene affected. But all of its modalities have something in common: specific white blood cells (the lymphocytes) work incorrectly or are not present, and therefore the body does not have an adequate immune system to defend itself against viruses, fungi and bacteria.
Without treatment, children born with this condition succumb to opportunistic infections and generally do not exceed the year of life.
According to Claire Booth, pediatric immunologist at the Great Ormond Street children’s hospital in London, it is estimated that “among all SCID forms there is 1 case every 100,000 births in the world. The most severe type is ADA deficiency. , where the patient lacks T, B and NK cells (also known as natural killers) “.
It is the disorder that Sarah was diagnosed with in 2016, and many years before David Vetter, an American boy whose story captured the public’s attention in the 1970s, and served as the inspiration for the movie “The Boy in the Plastic Bubble,” starring John Travolta.
Hence, the syndrome was popularly known as “the bubble boy disease”, a name by which many recognize it today.
At the time, the only possible treatment for SCID-ADA was a bone marrow transplant, and in the absence of a compatible donor, Vetter lived in a sterilized plastic chamber inside his home, and was only able to venture outside when NASA designed a special suit for him that allowed him to move around the outside world while remaining isolated.
Vetter died in 1984 at the age of 12, due to complications derived from a bone marrow transplant that they managed to do with a new technique at that time that did not require 100% compatibility.
Gene therapy, a revolutionary advance
Over the years, new treatments have appeared: while waiting for a compatible donor, patients are treated with antibiotics, injections of immoglobulin – a solution of human antibodies – and sometimes blood transfusions.
They are temporary, expensive, and inconvenient solutions.
However, a gene therapy put to the test by researchers at the University of California in the United States and Great Ormond Street Hospital in the United Kingdom during an experimental trial showed that it is possible to repair the immune system of children with SCID-ADA, without resorting to a transplant.
Treatment consists of first removing stem cells that make up the patient’s blood. Then, in the laboratory, using a viral vector called lentivirus, the genetic material that the patient is missing (a correct version of the ADA gene) is inserted into these cells.
These corrected stem cells, once re-engrafted into the patient, begin to produce a seemingly continuous supply of healthy immune cells capable of fighting infection.
Of the 50 children treated in both countries, 48 reestablished their immune function and resumed a normal life, that is, in contact with other children and without the need to continue with medication.
“We have seen more than one 95% efficient after two or three years of therapy, with which we are confident that it will be a long-lasting treatment “, tells BBC Mundo Booth, co-author of the study published in the journal New England Journal of Medicine.
During rehearsal no complications were reported, and most of the adverse effects of the therapy were mild or moderate. While the benefits, when compared to a bone marrow transplant are many, explains Booth.
Finding a compatible donor is not easy to begin with, especially for ethnic minority patients.
But also, “as (in a transplant) you are putting the cells of another person in the patient, there is always a risk that I will reject them, of a fight that can affect many organs in the body: the skin, the liver, the intestines, the lungs and that can be very serious, “says the immunologist.
“We also have to use chemotherapy before the transplant from an unrelated donor, to somehow empty the bone marrow and make room for the new cells to enter, and then the patient has to take immunosuppressive drugs for a long time to avoid a confrontation between his cells and those of the donor. ”
“Instead, since gene therapy uses the patient’s own cells, there is no risk of a fight. And because we don’t have to use as much chemotherapy before the procedure, it is, on the whole, much less toxic, “says Booth.
After gene therapy, “it takes about three months for the immune system to reach a good level and a little longer until it fully recovers. Therefore, the patient must take preventive medicines for the first six or twelve months. Then they can stop the most of them and start to socialize and lead a normal life. ”
“For families this is something incredible“, says the expert.
A “normal girl”
Sarah, the 5-year-old girl from South Yorkshire, is one of the patients whose life was changed by the trial.
Gone are the days when Sarah he couldn’t even kiss his daughter or sleep with her.
“If he touched my face, for example, I had to go wash my hands up to the elbow for two or three minutes. Sometimes they would bleed for that. If the pacifier fell on the floor, I had to sterilize it before giving it to him again. “, He says.
“I stayed with her almost all the time in the room, and I changed twice a day and also cleaned the house twice a day because of the need to protect her,” he says.
“Today Sarah goes to the park and we don’t have to clean the place where she sits every time, goes to school, to dance, to the vacation club … she is a normal girl, He has many friends, and even now we can have a pet in the house. ”
“Her life changed completely. And I am happy that everything happened when she was so little and could not realize what was happening.”
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Eddie is an Australian news reporter with over 9 years in the industry and has published on Forbes and tech crunch.