Scientists in Uganda, East Africa and Africa are now collaborating with
their colleagues in USA and UK in research work using gene therapy for sickle
cell patients and people living with HIV/Aids.
Scientists define Gene therapy as a technique that modifies a person's genes to treat or cure a specific
disease.
Gene therapies can work by several mechanisms including replacing a
disease causing gene with a healthy copy of the gene and inactivating a disease
causing gene that is not functioning properly among others.
Background
Experts explain that
gene therapy technology works well by using genes and deoxyribonucleic acid (DNA).
Genes include the
Mendelian gene which is a basic unit of heredity and the molecular gene is a
sequence of nucleotides in DNA that is transcribed to produce a functional RNA
DNA is the material
that carries all the information about how living things will look and
function. It supplies the genetic instructions that tell the body how to
develop, live and reproduce.
Therefore since
sickle cell and HIV/Aids are known to be diseases for developing countries
especially in Africa and Uganda inclusive with no cure, scientists across the
globe in collaborative effort are currently researching using gene therapy
technology to find a cure for people suffering these diseases.
Scientists in USA are
already in advanced stages of the research where they have products with
products already being used.
They are already
collaborating with scientists in Uganda where the initiative is led by
scientists at the Joint Clinical Research Center (JCRC) who are currently
preparing to implement the research activities in Uganda.
The facilities are
already in place including laboratory equipment and research work will kick off
from 2024.
This was revealed to
a group of science journalists during a monthly biocafe in Uganda’s Kampala
recently.
The Deputy Director
of JCRC Dr Francis Ssalli took the journalists through the topic “Preparedness
for gene therapy research and clinical services for the health and wellbeing of
Ugandans” and below are the details.
Current Gene
Therapy research Pattern
According to Dr Ssali
sickle cell and HIV/Aids are a major challenge in Africa with Uganda ranking
number 5 in sickle cell pandemic after Nigeria, Democratic Republic of Congo
and Tanzania
Apparently the
genetic engineering law which covered mainly issues related to agriculture
Technology is now being reviewed by Uganda's Parliament to include aspects of
advanced research in the health sector using gene therapy technology to allow
scientists in the health sector to carry out research.
The aim is to get a
cure for sickle cell and HIV/ Aids patients within the country and which is
affordable. Currently patients who can afford are taken to countries such as
India and USA to sick for sickle cell treatment using gene therapy technology.
Mr Ronald Jagwe from
Uganda National Council for Science and Technology noted that Health care,
environment including agriculture are
now key areas to be considered o=in modifying biosecurity laws
“Scientists are now
prepared to apply modification technologies including issues of biosecurity and
our scientists in the health sector are researching on use of gene therapy to
address health challenges people are faced with,”
Dr Ssali notes that
“what we know in health is that people are given medication either using
injectable or tablets. Today we are advancing by using cells which can be
obtained from another person to administer treatment. Colleagues from the
agriculture sector have advanced in using these technologies where seed can be
modified to increase yields,”
He adds that in the
health sector scientists have not utilized human seed for modification to
obtain cure but gene therapy has come on to address this incurable diseases.
Although trials are still ongoing and
the long-term effects are still unclear, promising results show the potential
for gene therapy as a treatment option.
Red blood
cells contain haemoglobin which is a molecule that delivers oxygen to the
body’s tissues which sickle cell patients’ lack.
In sickle
cell disease, a problem with haemoglobin means that the red blood cells are C
shaped like a sickle.
As a result,
they can stick in the cardiovascular system. They are also unable to deliver
oxygen effectively. This can affect the body in various ways.
Currently the
only cure for sickle cell disease is a stem cell transplant, but
organizations such as the Sickle Cell Disease Association of America are
working to raise awareness and encourage funding for more research into this
condition.
According to
a US based Genetic Home Reference,
sickle cell disease affects people whose ancestors come from Africa,
Mediterranean countries such as Greece, Turkey and Italy, the Arabian
Peninsula, India, and Spanish-speaking regions in South America, Central
America and parts of the Caribbean.
Types
HbSS is wher
a person inherits two sickle cell genes, one from each parent. They will
have sickle cell anemia, which is the most severe type of sickle cell disease.
HbSC is where
a person inherits a sickle cell gene from one parent. From the other
parent, they inherit a gene that results in another type of abnormal
hemoglobin. This type is usually less severe than HbSS.
HbS beta-thalassemia is where a person inherits a sickle cell gene from one parent
and a gene for beta-thalassemia, another type of anemia.
Sickle cell trait: is where
if a person has only one sickle cell gene, they will not have sickle cell
disease, but they can pass that gene to their children.
Statistical
Data
According to
the Centers for Disease Control and Prevention (CDC), about100, 000 people in
the United States have sickle cell disease. Around 1 in 365 Black Americans are
born with the disease, and 1 in 13 are born with the trait. Sickle cell disease
affects about 1 in 16,300 Hispanic Americans.
The 2008 United Nations report estimates that there are between 20 and
25 million people worldwide living with SCD, of which 12–15 million live in Africa. The
disease appears to be
more likely in areas where is common
Apparently
Uganda is rated number with sickle cell prevalence in Africa after Nigeria,
Democratic Republic of Congo, Tanzania and Sudan.
Symptoms
They include
yellowing of the skin and white eyes, fatigue, pain and swelling in the hands
and feet, acute chest syndrome, vision loss, enlarged spleen, liver, heart, or
kidney damage, malnutrition in the young and infertility in males because
causing prolonged painful erection
leading to high blood pressure and borne joint damage.
Medication
Apparently the drugs include
Hydroxyurea (Hydrea) which helps ensure the supply of oxygen to
the body.
Others are L-glutamine
oral powder (Endari) which helps reduce the number of sickle
cells, Voxelotor (Oxbryta) helps to boost haemoglobin supply
and Crizanlizumab-tmca which helps reduce pain.
Gene therapy technology
application
According to Dr Ssali clinical
trial have been in sickle in USA patients and there is treatment in place
This is done by isolating stem
cells using bio vectors where virus that enter the cells will deliver stem
cells. The gene the patient is obtained and cloned in the Laboratory. The virus
will then infect the cells and the vector goes through the pours to deliver the required protein.
The cells that are isolated will
get processed in 4 days and this is injected in the patient.
These process can be used to treat
sickle cell which affects lymphocytes at the throat and this is done using T-
cells where the t=gland will get trained to fight the disease.
Gene therapy application on
HIV/Aids patients
Dr Ssali contends that the same
process scientists go through modifying cells to treat sickle cell is done for HIV/ Patients.
“For HIV/AIDS we use are currently using anti-retroviral drugs as
treatment for patients. Gene therapy technology use for started in US, India
and UK and the first generation trials for cure is almost complete. This is a
step already because in Uganda in 1980’s scientists were doing nothing but we
have prepared the laboratory equipment and in 2030 we should be able to get a
cure,”
So far scientists in USA have
done 6 clinical trials using the CRISPR- Cas9 enzyme modification where cells
were removed from a patient for evaluation.




