Scientists just used CRISPR gene-editing techniques to remove HIV from human T-cells

Scientists managed to eliminate HIV-1 DNA from T cell genomes in human lab cultures. It will take time for advanced use in humans, but it is a remarkable accomplishment.

Using the much-touted CRISPR/Cas9 gene editing method, scientists have demonstrated how they can edit HIV out of human immune cell DNA, and in doing so, can prevent the reinfection of unedited cells too.

If you haven’t heard of the CRISPR/Cas9 gene-editing technique before…It allows scientists to narrow in on a specific gene, and cut-and-paste parts of the DNA to change its function.

Earlier this year, scientists started using CRISPR/Cas9 to successfully treat a genetic disease – Duchenne muscular dystrophy – in living mammals for the first time, and now it’s showing real potential as a possible treatment for HIV in the future.

The technique works by guiding ‘scissor-like’ proteins to targeted sections of DNA within a cell, and then prompting them to alter or ‘edit’ them in some way. CRISPR refers to a specific repeating sequence of DNA extracted from a prokaryote – a single-celled organism such as bacteria – which pairs up with an RNA-guided enzyme called Cas9.

So basically, if you want to edit the DNA of a virus within a human cell, you need a bacterium to go in, encounter the virus, and produce a strand of RNA that’s identical to the sequence of the virtual DNA.

This ‘guide RNA’ will then latch onto the Cas9 enzyme, and together they’ll search for the matching virus. Once they locate it, the Cas9 gets to cutting and destroying it.

Using this technique, researchers from Temple University managed to eliminate HIV-1 DNA from T cell genomes in human lab cultures, and when these cells were later exposed to the virus, they were protected from reinfection…

While gene-editing techniques have been trialled before when it comes to HIV, this is the first time that scientists have figure out how to prevent further infections, which is crucial to the success of a treatment that offers better protection than our current antiretroviral drugs.

Bravo! As usual, technology and science are themselves immune from Good and Bad. Those uses are defined by the humans who use advances to their own ends. That’s where ethics are required. Full credit to Kamel Khalili and fellow researchers at Temple University who brought their talents to bear on one of the scourges of the 20th Century and more.

Reprogrammed T-cells train immune system to kill cancer

A year ago, when chemotherapy stopped working against his leukemia, William Ludwig signed up to be the first patient treated in a bold experiment at the University of Pennsylvania. Mr. Ludwig, then 65, a retired corrections officer from Bridgeton, N.J., felt his life draining away and thought he had nothing to lose.

Doctors removed a billion of his T-cells — a type of white blood cell that fights viruses and tumors — and gave them new genes that would program the cells to attack his cancer. Then the altered cells were dripped back into Mr. Ludwig’s veins.

At first, nothing happened. But after 10 days, hell broke loose in his hospital room. He began shaking with chills. His temperature shot up. His blood pressure shot down. He became so ill that doctors moved him into intensive care and warned that he might die. His family gathered at the hospital, fearing the worst.

A few weeks later, the fevers were gone. And so was the leukemia.

There was no trace of it anywhere — no leukemic cells in his blood or bone marrow, no more bulging lymph nodes on his CT scan. His doctors calculated that the treatment had killed off two pounds of cancer cells.

A year later, Mr. Ludwig is still in complete remission. Before, there were days when he could barely get out of bed; now, he plays golf and does yard work.

“I have my life back,” he said.

Mr. Ludwig’s doctors have not claimed that he is cured — it is too soon to tell — nor have they declared victory over leukemia on the basis of this experiment, which involved only three patients. The research, they say, has far to go; the treatment is still experimental, not available outside of studies.

But scientists say the treatment that helped Mr. Ludwig…may signify a turning point in the long struggle to develop effective gene therapies against cancer. And not just for leukemia patients: other cancers may also be vulnerable to this novel approach… In essence, the team is using gene therapy to accomplish something that researchers have hoped to do for decades: train a person’s own immune system to kill cancer cells.

RTFA. Hope is a wonderful word. Accompanied with science and innovation, courage and care – so much may yet be achieved.

Immune system thwarted to allow pregnancy.

The concept of pregnancy makes no sense — at least not from an immunological point of view. After all, a fetus, carrying half of its father’s genome, is biologically distinct from its mother. The fetus is thus made of cells and tissues that are very much not “self” — and not-self is precisely what the immune system is meant to search out and destroy.

Women’s bodies manage to ignore this contradiction in the vast majority of cases, making pregnancy possible. Similarly, scientists have generally paid little attention to this phenomenon — called “pregnancy tolerance” — and its biological details.

Now, a pair of scientists from the California Institute of Technology (Caltech) have shown that females actively produce a particular type of immune cell in response to specific fetal antigens — immune-stimulating proteins — and that this response allows pregnancy to continue without the fetus being rejected by the mother’s body…

Scientists had long been “hinting around at the idea that the mother’s immune system makes tolerance possible…”What they didn’t have were the details of this tolerance — or proof that it was immune-related.

Now they do…

RTFA. Or spend the money and read the original paper at PNAS.

Patient’s own infection-fighting T-cells put late-stage melanoma into long-term remission


Researchers describe the first successful use of a human patient’s cloned infection-fighting T cells as the sole therapy to put an advanced solid-tumor cancer into long-term remission. A team led by Cassian Yee, M.D., reports these findings in the New England Journal of Medicine.

Yee and colleagues removed CD4+ T cells, a type of white blood cell, from a 52-year-old man whose Stage 4 melanoma had spread to a groin lymph node and to a lung. T cells specific to targeting the melanoma were then expanded vastly in the laboratory using modifications to existing methods. The lab-grown cells were then infused into the patient with no additional pre- or post-conditioning therapies, such as growth-factor or cytokine treatment. Two months later, PET and CT scans revealed no tumors. The patient remained disease free two years later, when he was last checked…

Yee cautioned that these results, presented in the journal’s “Brief Report” section, represent only one patient with a specific type of immune system whose tumor cells expressed a specific antigen. More studies are needed to confirm the effectiveness of the experimental T-cell therapy. If proven successful in more patients, Yee predicted this therapy could be used for the 25 percent of all late-stage melanoma patients who have the same immune-system type and tumor antigen.

Cripes! Even if a very specific set of circumstances are required, this could be the beginning of a dynamic new mode of treatment for cancers.