/ 10 April 2021

More ethnically diverse bone marrow donors needed to save lives

Dkms Laboratory In Dresden
Too monochrome: The world’s pool of bone marrow donations are kept in cold storage vaults such as this one in Dresden, Germany. (Robert Michael/Picture Alliance)

A lack of ethnic diversity among donors, coupled with cultural myths, have led to a paucity of bone marrow donors, resulting in hundreds of avoidable deaths caused by leukaemia and other blood-related diseases.

According to Jane Ward, the deputy director of the South African Bone Marrow Registry (SABMR), the lack of sufficient education to counter cultural beliefs, especially among black South Africans, contributes to donor resistance. A common myth is that regenerative stem cells are somehow body parts and cannot be parted with. 

She said a major education and destigmatisation campaign is needed to help people donate — and to realise that help is available.

“Also, by the time many black patients go to a doctor or clinic to be referred upwards for treatment, it’s often too late. We can only transplant bone marrow when a patient is in remission, and that requires extensive treatment. 

“If you don’t catch it quickly enough, you can’t treat it. That and the lack of facilities, plus the costs — which we cover for matching, donor collection and stem cell transport — have proved the biggest hurdles,” Ward said. 

“You’re more likely to find a match within your own ethnic group and it’s been shown that there are more white donors on registries worldwide. There’s simply not enough ethnic diversity among donors.”

Two other societal phenomena have contributed to shrinking the local bone marrow registry base from 74 000 to 73 000 donors over the past five years: emigration and ageing.

Last year, of those donors removed from the local donor base, more than 6% were lost because of emigration, Ward revealed. 

And because stem cells age with their hosts, donors are retired from the database at 60 years old.

“Emigration is not a train smash because we contact them and transfer them to the registry of the destination country – but that ups the cost in getting the donor cells transported back here,” she explained.

A new partnership between the SABMR and Netcells, South Africa’s largest private cord blood bank, is set to improve access to more cost-effective, life-saving treatment for leukaemia and some 79 other blood related diseases.

While 550 patients have received matched unrelated transplants since the SABMR was established in 1991 — an outflow of critical tissue matching capability required for Dr Chris Barnard’s historic 1967 heart transplant — the chances of finding a bone marrow match remain slim. 

This new partnership includes the establishment of a public community cord blood stem cell bank — Africa’s first — and marks another milestone in reducing the one-in-100 000 odds of finding a bone marrow match for patients in South Africa.

While South Africa has been part of the world registry for bone marrow transplants for 20 years, giving it access to some 39-million registered donors, there are only 73 000 South African donors in an ageing local registry. 

This puts South Africans at a major cost and access disadvantage. One of the biggest stumbling blocks remains the few black (global and local) donors and the gap between South Africa’s funded private transplant funding and unfunded state sector transplants — which the community cord blood stem cell bank aims to address.

Ethnic diversity hurdle

There are other reasons why donor recruitment remains so low.

The SABMR only began recruiting donors in 2018, meaning it had to develop a recruitment division from scratch after the well-known Sunflower Fund relinquished this task as part of its cancer treatment funding efforts.

Ward said that recent advances in medical technology have brought umbilical cord blood stem cells to the table as an effective treatment. Besides infant cord blood stems cells, blood from young healthy males aged 18 to 25 is the preferred transplant choice. Although that age bracket is the preferred choice, any one who is healthy and younger than 60 can donate.

Lisa King, a Sangamo BioSciences Inc. research associate, isolates DNA at the Sangamo BioSciences lab in Point Richmond, California, U.S., on Photographer: David Paul Morris/Bloomberg via Getty Images

According to Ward, a consequence of this reality is that South Africa recently became only the second country globally to drop the donor recruitment age from 18 to 16 in its attempt to swell the registry.

“Education is vital to counter myths and create a younger, informed donor base. We want everybody in the next generation to know about this life-saving treatment and how they can help.” 

One way to achieve this is to use new channels such as TikTok and Instagram for the younger generation being targeted. 

Widening local availability

Shelley Bredin, the managing director of Netcells, outlined how her company works and will partner with the SABMR.

Netcells receives umbilical cord blood stem cells from infants at birth, freezing them for future use. The parents opting to do this do so as an insurance against future blood-based diseases. 

The umbilical stem cells are also a 25% match for a sibling, widening the “insurance safeguard”. Parents can, at the outset, choose whether to opt for community stem cell banking or private stem cell banking, the former costing half the price (R15 000). This is in return for the stem cells being allocated on a priority needs basis to either their family or an outside matched recipient — on a first-come-first-served basis — via the SABMR registry. 

If the community banked stem cells are used for an outside recipient, the parents are reimbursed fully. Once the initial selected storage period ends, when privately banking the stem cells, Netcells contacts the parents and asks them if they want to continue storage or to donate them to the SABMR as a philanthropic gesture.

If parents opt for private stem cell banking, the frozen cells are kept exclusively for their use, but the up-front price increases to R29 000 for 10 years’ storage.

“It’s a very personal decision,” she said. “Our intention is to make the stem cells more attainable for more people and at the same time serving to expand the donor pool in South Africa. Some who have the money would still prefer to bank privately as they don’t want to take the gamble.”

Impact of Covid-19 

Cost remains an ever-present reality, with Covid-19 dramatically reducing the global pool of available and usable donor blood cells.

“It’s no longer just an issue of an adult donor having to be medically fit. The question becomes, will the donor get Covid? You have to test [the donor], for that. Yet [umbilical] cord blood remains readily available, and you don’t need a whole bunch of tests on the donor,” Bredin said

This was yet another current contextual advantage of the new partnership, she emphasised.

Bredin said cord blood is a much simpler source of stem cells than an adult’s blood. By establishing a community cord blood bank, they hope to reduce the need for expensive global sourcing. 

An adult blood cell donation can cost between R250 000 and R270 000 from a foreign country (just over half that locally) while foreign-sourced umbilical cord blood can cost up to R1-million. Only a very few local medical aids fund all sourced donations and transplants.

Leukaemia is the most common cancer among children and teens worldwide, accounting for 30% of all cancers diagnosed in children.

The miraculous, life-saving bone marrow transplant addressing end-stage haematological disorders happens just 12 500 times a year globally, according to the SABMR.

Anyone wanting to find out more about stem cell harvesting and donation or who would like to contribute to the SABMR donor fund to help save lives should visit nextbio.co.za/netcells/ or sabmr.co.za/become-a-donor/. Alternatively they can email: [email protected]