JAN 28, 2021 6:00 AM PST

Killers With a Hit on the Spike

WRITTEN BY: Tara Fernandez

Natural killer cells, or NK cells, are specialized immune cells of the innate immune system. Their job revolves around eliminating the spread of cells that are either cancerous or that have been infected by pathogens. 

Certain cell therapy strategies aim to harness the power and potential of NK cells by genetically modifying them to target specific antigens. A recent study has demonstrated that one of these potential targets is the spike protein of the COVID-causing coronavirus, SARS-CoV-2. The research team that performed the work were from the Center for Immunity and Inflammation at the New Jersey Medical School.

For cell therapy applications, the modification of the cells involves the isolation of immune cells from the peripheral blood or bone marrow before genetically engineering them to express the chimeric antigen receptor or CAR. Approved cell therapies using CAR-T cells, mostly for cancer treatments, have not been the first choice as COVID therapies. In some patients, the administration of CAR-Ts can result in the side effect of raising systemic levels of cytokines in the body, similar to the “cytokine storm” caused by SARS-CoV-2 infections. CAR-NKs, however, are gentler and less likely to have these unwanted adverse effects.

In the study published in the bioRxiv preprint server, scientists developed NK cells that express CAR using the S309 antibody—an antibody isolated from individuals who had recovered from COVID infections, which showed high affinity for the spike protein of the virus, which upon binding, neutralizes it.

Why not just use the S309 antibody as a therapeutic? Because, say the authors, the half-life of monoclonal antibody therapies is only around three weeks. In contrast, these modified NK cells persist for much longer, forming a more potent and lasting shield against infection symptoms.

The next steps are to further validate S309-CAR-NK against full viral particles rather than the pseudotyped spike protein molecules used in the study. Testing in pre-clinical animal models will also help predict the potential efficacy of the new therapy in patients.

“These results pave the way for generating ‘off-the-shelf’ S309-CAR-NK cells for treatment in high-risk individuals as well as provide an alternative strategy for patients unresponsive to current vaccines,” wrote the authors in the manuscript.

 

 

Source: bioRxiv.


 

About the Author
  • Tara Fernandez has a PhD in Cell Biology and has spent over a decade uncovering the molecular basis of diseases ranging from skin cancer to obesity and diabetes. She currently works on developing and marketing disruptive new technologies in the biotechnology industry. Her areas of interest include innovation in molecular diagnostics, cell therapies, and immunology. She actively participates in various science communication and public engagement initiatives to promote STEM in the community.
You May Also Like
OCT 15, 2020
Immunology
The Immune Cells Giving Menopausal Women Higher BPs
OCT 15, 2020
The Immune Cells Giving Menopausal Women Higher BPs
In general, men have higher blood pressures than women, giving them an increased risk of developing heart disease. After ...
OCT 20, 2020
Immunology
The Immune Pause Button Slowing MS Progression
OCT 20, 2020
The Immune Pause Button Slowing MS Progression
  Scientists have a new theory about the genetics behind the progressive, debilitating effects of multiple sclerosi ...
DEC 08, 2020
Immunology
Drug Targets Cold Tumors' Achilles Heel
DEC 08, 2020
Drug Targets Cold Tumors' Achilles Heel
Immunotherapies have emerged as a powerful treatment modality for cancer. They join chemotherapy, surgery, radiotherapy, ...
DEC 29, 2020
Immunology
Cancer-Killing Viruses Enter in Stealth Mode, Penetrate Immune Barrier
DEC 29, 2020
Cancer-Killing Viruses Enter in Stealth Mode, Penetrate Immune Barrier
Viruses that when administered to patients preferentially attack and kill cancer cells, leaving normal tissues unscathed ...
JAN 05, 2021
Immunology
Immune Imbalances Dictate COVID Symptom Severity
JAN 05, 2021
Immune Imbalances Dictate COVID Symptom Severity
COVID symptoms. “As it is often the case for pathogenic infections, the host immune system is a key player in vira ...
FEB 01, 2021
Microbiology
A Potential Leptospirosis Vaccine is Created
FEB 01, 2021
A Potential Leptospirosis Vaccine is Created
Spirochetes are a type of free-living, spiral-shaped bacteria, some of which are harmless and others that can cause dise ...
Loading Comments...