CRISPR-Cas9 tagged posts

For CRISPR, Tweaking DNA fragments before Inserting yields Highest Efficiency Rates yet

Image result for Gene KI strategy using Cas9 RNP and end-modified dsDNA donors.
Gene KI strategy using Cas9 RNP and end-modified dsDNA donors.

University of Illinois researchers achieved the highest reported rates of inserting genes into human cells with the CRISPR-Cas9 gene-editing system, a necessary step for harnessing CRISPR for clinical gene-therapy applications.

By chemically tweaking the ends of the DNA to be inserted, the new technique is up to five times more efficient than current approaches. The researchers saw improvements at various genetic locations tested in a human kidney cell line, even seeing 65% insertion at one site where the previous high had been 15%.

Led by chemical and biomolecular engineering professor Huimin Zhao, the researchers published their work in the journal Nature Chemical Biology...

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Herpes’s Achilles Heel

microscopy image of herpes simplex virus
Scientists have used gene editing to disrupt both latent and actively replicating herpes simplex virus in human cells. Image: Aunt_Spray/iStock/Getty Images

In a first, scientists use gene-editing to disrupt both latent and active herpes virus in human cells. Scientists have used the gene-editing tool CRISPR-Cas9 to disrupt both latent reservoirs of the herpes simplex virus and actively replicating virus in human fibroblast cells. Experiments pinpoint weak spot that can make the virus susceptible to gene editing.

The herpes simplex virus, commonly known as the cold sore virus, is a devious microbe.

It enters the body through regions lined with mucous membranes – mouth, nose and genitals – but quickly establishes lifelong viral hideouts inside nerve cells...

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Targeting a Blood Stem Cell subset shows lasting, Therapeutically Relevant Gene Editing

Microscopy image of blood stem cells that will go through CRISPR/Cas9 gene editing in a lab dish. Credit: Kiem lab / Fred Hutchinson Cancer Research Center

Researchers at Fred Hutchinson Cancer Research Center used CRISPR-Cas9 to edit long-lived blood stem cells to reverse the clinical symptoms observed with several blood disorders, including sickle cell disease and beta-thalassemia. It’s the first time that scientists have specifically edited the genetic makeup of a specialized subset of adult blood stem cells that are the source of all cells in the blood and immune system.

The proof-of-principle study suggests that efficient modification of targeted stem cells could reduce the costs of gene-editing treatments for blood disorders and other diseases while decreasing the risks of u...

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HIV Eliminated from the Genomes of Living Animals

A working model for HIV-1 elimination. A cartoon illustration of the viral elimination strategy is shown for single LASER ART, AAV9-CRISPR-Cas9 injection groups and dual treatment groups. We highlight the observed restriction of viral infection by LASER ART and an inability to achieve elimination of virus by AAV9-CRISPR-Cas9 treatment alone. However, the sequential administration of LASER ART and AAV9-CRISPR-Cas9 can achieve viral elimination in a subset of animals. Why specific animals are cured of infection while others are not is incompletely understood but tied, in measure, to viral set points

Researchers have for the first time eliminated replication-competent HIV-1 DNA – the virus responsible for AIDS – from the genomes of living animals...

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