- HIV is a dreaded virus
that leads to the development of AIDS. Some people are immune to HIV infection.
- HIV hides in certain genes that aid in avoiding drug
- Current study identifies that mutation in
CXCR4/CCR4 leads to immunity against HIV.
system used to edit genes in T-cells to induce immunity.
affects the T cells in the body and
prevents them from mounting a response.
A few individuals are found to be resistant to HIV infection and such
individuals were studied by researchers
from The University of California
San Francisco to identify the mutations that gave rise to the immunity. The new
gene editing tool CRISPR/cas9 system was used to edit the specific gene
elements to determine if it leads to immunity against the virus.
infection has affected 78 million people
million people are believed to have died due to the
- In 2015, 38.7 million people were found to live
- 1.8 million were children.
the same year 1.1 million died of the illness.
The infection is dreaded
across the world as it is sexually transmitted with limited medical support.
The virus gets into the DNA of the immune cells and is difficult to remove from
the system with the currently available medication. This necessitates life-long
‘T-cells that are attacked by HIV can now be made immune using the CRISPR/Cas 9 system, raising hopes for a better cure for AIDS.’
individuals host an immune response that prevents the growth and multiplication
of HIV, this lead the researchers in the current study to identify the genetic
pattern of these HIV resistant
One of the lead authors
of the study, Judd F. Hultquist said "There
have been lots of efforts to sequence the genomes of resistant people to
discover the mutations that make them immune to the virus. But there are many
different genes that could be involved: some control the virus's ability to
enter immune cells, others control how the virus tricks cells into expressing
its genes. Until now, there was no way to test which of these mutations
actually confer resistance in primary human T-cells."
Replacement using CRISPR
The human T cells
survive for a very short time out of the human body and hence, any study that
needs to be carried out on the T-cells has to be immediate. The use of viruses
in earlier studies to create changes to the DNA proved futile when immune cells
In the current study,
the research team was able to produce changes to the immune cell DNA using the CRISPR/Cas 9 system
The specially designed
CRISPR/Cas 9 system were added to immune cells that were freshly harvested and
the gene editing tool made the appropriate changes after which it underwent
cellular degradation before it could make any further changes to the immune
DNA Mutations Using High Throughput Parallel T cell Editing System
The researchers in the
study used high throughput T-cell DNA editing system where candidate genes at
different positions in the T cell DNA of many T-cells were carried out in
parallel. These T-cells were then exposed to HIV to
identify which mutation rendered the cell immune to the virus.
This new technique
increased the speed as many DNA mutations could be carried out within a short
period of time, which is highly critical as T-cells last only for a short while
outside the body. If this technique
needs to be tailored for a cure, carrying out the DNA mutation within a short
period of time will form the crux of the treatment as the DNA of the T cells
need to be altered and then injected into the patient within a short period of
researchers identified two genes CXCR4 and CCR4 into which the HIV 'hid' during
an infection. When these two genes were mutated, the cells were immune to the
study on the infectivity of HIV and the resultant immunity in certain T cells
could lead to better treatment for HIV.
Highlights of the Study:
- The study found that mutations in
the genes CXCR4 and CCR4 were found to provide immunity against HIV infection.
- CRISPR/Cas 9 system was used to edit the genes of freshly
harvested immune cells of susceptible individuals.
processes of editing and reintroduction into the host were completed within a
short span of time, a first of its kind and of high relevance as T-cells
survive for a very short time outside the body.
better method of treatment as well as prophylaxis against HIV.
- Global HIV and AIDS statistics - (http://www.avert.org/global-hiv-and-aids-statistics)