Cells that offer hope

CHENNAI: Rare diseases are anything but rare. Several international studies suggest there are 7,000 unique disorders affecting over 400 million people in the world. And the number is increasing, with nearly 250 new diseases being classified as rare diseases each year.

This is where stem cell transplant, also known as bone marrow transplant, plays an important role, as it can treat many rare blood cancers and blood disorders. Stem cells can be retrieved from blood vessels and bone marrow.

On Rare Diseases Day, experts tell DT Next about the important role of stem cell transplant in treating several types of rare genetic diseases and the challenges in encouraging people to donate stem cells.

For instance, in August last year, when a man was diagnosed with leukaemia, his family was informed that he was chemo-resistant and that the conventional method of chemotherapy would not help him. A bone marrow transplant could have given him a fresh lease of life. However, with low awareness about stem cell donation and very few registered donors, it was next to impossible to find a match.

No awareness

Experts say that there are over 100 blood disorders and cancers that can be treated through stem cell transplant. While awareness is slowly picking up and more people are volunteering to donate, this needs more impetus.

There’s awareness for thalassemia and sickle cell anaemia but this is just 2 out of the long list of rare diseases in the world today. Acute myeloid leukaemia, chronic granulomatous disease, Krabbe disease, Hurlers syndrome etc are a few of the thousands that the public has never heard of.

Sumati Misra, head of counselling and transplant centre management at DATRI Blood Stem Cell Donor Registry, claims stem cell transplant has been successful in treating over 100 blood disorders and cancers.

“Many people are dissuaded by their family and other influencers in the extended family. They don’t know how difficult it is to find a match. Only 25% of patients find a match within their family and the rest have to find donors in registries. Finding a matched unrelated donor is a challenge – the odds are 1:10000 to 1:1 million,” says Sumati.

She added that ethnicity matters, and hence patients of Indian origin have a higher chance of finding a match within an Indian registry. Though there are over 5 lakh registered donors, that’s less than 1% of the Indian population.

There are many genetic diseases (like sickle cell anaemia) that can be diagnosed accurately in foetal life itself by examining foetal DNA. Some of these diseases are treated after birth by stem cell transplantation. However, the success of it is limited by lack of donors, progression of disease in the baby, rejection of donor cells by the baby’s immune system, and, in rare cases, rejection of baby’s tissue by donor cells.

Out-patient procedure

Lack of awareness leads to myths regarding stem cell donation. Many matched donors do not want to donate, or are dissuaded by their friends and loved ones.

“This is a very safe, painless and quick out-patient process. The donor is awake throughout the donation in most cases. We need more people to register and donate,” adds Sumati.

For patients from middle and lower middle-class families, the situation is dire. Guidance on treatment, financial support and planning are critical factors affecting access to stem cell transplantation in India.

“While anyone can be a stem cell donor, people hesitate because donors fear long-term side-effects or would lose something valuable if they donate. It’s unfortunate that despite a huge population, we have very few donors,” points out Dr Sathyamurthy, senior oncologist, Stanley Medical College and Hospital.

Financial burden

While affordable cancer care is unavailable for a large section of the society here, rare disorders make it worse, due to limited access to facilities and treatment.

Every year, over 1 lakh people are diagnosed with blood cancer or blood disorders such as thalassemia or aplastic anaemia in India. With over 42 million carriers, the country is also known as the thalassemia capital of the world.

The most effective treatment for such life-threatening diseases is a blood stem cell transplant, ideally at an early age. Even for those who get access to appropriate health care, this often results in heavy social and financial burdens.

The Tamil Nadu government releases Rs 5 crore for treatment of patients with rare diseases. In December 2020, the Madras HC directed the Union Government to release Rs 4.4 crore for treating patients with rare diseases in the State.

The Union Health Ministry grants Rs 50 lakh for patients belonging to all categories of rare diseases, under the National Policy for Rare Diseases, 2021. The budget allocation for the financial year 2022-2023 towards rare diseases was Rs 25 crore.

HLA match

Stem cells are the mother of all cells and can produce all the significant cells in our body. Since they’re also found in the bone marrow, the procedure involves mobilising the cells in the blood.

It is important in stem cell transplants to see how closely the HLA (human leukocyte antigens) of the transplant patient matches the HLA of the donor. This is done by taking a blood sample. HLAs are protein molecules (markers) we inherit from our parents.

Although it’s similar to blood donation, HLA is rare to find. “The best way to get stem cells is from your siblings. However, the chances of getting matched are only about 25%,” explains Dr MP Ram Prabu, senior consultant, medical oncologist, Gleneagles Global Health City. “Both the donor and receiver must be cautious and be prepared (physically and mentally) for the transplant. Doctors must ensure that the patient is infection-free for 30 days after stem cells are infused. Then, there’s an impact witnessed in the blood count as it’d increase in a week.”

Rare diseases in India

Until 31 October 2021, there were 4,001 rare diseases recorded. The most common among them are haemophilia, thalassemia, sickle cell anaemia, primary immune deficiency in children, autoimmune diseases, Lysosomal storage disorders (such as Pompe disease), Hirschsprung disease, Gaucher’s disease, Cystic Fibrosis, Haemangioma, and some forms of muscular dystrophy.

Stem cell therapy can potentially treat

ALS, Alzheimer’s, autoimmune & neurological conditions, Chronic obstructive pulmonary disease (COPD), Crohn’s Disease, Diabetes (Type 1), heart failure, diseases of the kidney and liver, Lupus, Lyme disease, Multiple Sclerosis, Neuropathy, Parkinson’s, Reflex Sympathetic Dystrophy (RSD), Spinal cord injury, Stroke, Traumatic Brain Injury (TBI)