Designer protein patches boost cell signaling

January 06, 2021

A new class of protein material that interacts with living cells without being absorbed by them can influence cell signaling, a new study shows. The material does this by binding and sequestering cell surface receptors.

The discovery could have far-reaching implications for stem cell research and enable the development of new materials designed to modulate the behavior of living systems.

The research, reported in the January 6 edition of Nature, was led by the Baker lab at the University of Washington School of Medicine and the Derivery lab at the Medical Research Council Laboratory of Molecular Biology in Cambridge, U.K. Their paper is titled, Design of Biologically Active Binary Protein 2D Materials.

Cells interact with their environment via receptors at their surface. These receptors can bind to hormones, neurotransmitters, drugs, and toxins. When such molecules bind to a receptor, this triggers a response inside the cell, a process known as signaling.

But for the cell, it is important that this response be transient, to still be responsive to the signal later on. To achieve this, cells will commonly terminate signaling by absorbing both an activated receptor and the molecule that stimulated it, thereby targeting both for destruction inside the cell.

"This tendency of cells to internalize receptors likely lowers the efficiency of immunotherapies," said Emmanuel Derivery, assistant professor at the MRC Laboratory of Molecular Biology. "Indeed, when antibody drugs bind their target receptors and then become internalized and degraded, more antibody must always be injected."

To create a way around this, Baker lab postdoctoral scholar Ariel Ben-Sasson designed new proteins that assemble into large, flat patches. This molecular scaffolding was then further engineered to contain signaling molecules.

Graduate student Joseph Watson of the Derivery lab showed that such protein materials could latch onto cells, activate surface receptors, and resist being absorbed by the cell for hours or even days.

"This work paves the way towards a synthetic cell biology, where a new generation of multi-protein materials can be designed to control the complex behavior of cells," said David Baker, professor of biochemistry at the UW School of Medicine and director of the UW Medicine Institute for Protein Design.

By swapping out which cell surface receptors were targeted by the patch, the researchers showed that different cell types could be activated.

"We now have a tool that can interact with any type of cells in a very specific way," said Ben-Sasson. "This is what is exciting about protein engineering: it opens fields that people may not expect."

According to co-author Hannele Ruohola-Baker, professor of biochemistry at the UW School of Medicine and associate director of the UW Medicine Institute for Stem Cell and Regenerative Medicine, versions of these new materials could eventually help physicians alleviate the dangers of sepsis by controlling the inflammatory response to infection.

They might even enable entirely new ways to treat COVID-19, heart disease, and diabetes, and perhaps mitigate the downstream effects of strokes, including Alzheimer's disease.

"This breakthrough helps pave the way for the use of synthetic cell biology in regenerative medicine," said Ruohola-Baker.
This news release was written by Ian Haydon of the UW Medicine Institute for Protein Design. Full
Creator: Ariel Ben-Sasson, UW Medicine

Title: Binary protein 2D assembly animation

Self-assembly is a process where same molecules, or building blocks, interact to form complex materials. This animation shows yet a more complex process - co-assembly - where materials are assembled from a mix of two different building blocks. For materials engineers and biologists looking for new tools this development allows to control where, when, or under what conditions the material would assemble and its emergent properties evolve. A Jan. 6, 2021 paper in Nature shows that bioengineers can form flat arrays embedded to cell surfaces, trigger and boost biological activation through receptors clustering and uptake impediment (endocytosis block). This proof-of-concept demonstrates the far-reaching potential of this new class of designer materials to narrow the gap between synthetic and living systems. This video was produced using python and the Pymol graphical interface (Schrödinger).

University of Washington Health Sciences/UW Medicine

Related Stem Cell Articles from Brightsurf:

Fat cell hormone boosts potential of stem cell therapy
Mesenchymal stem cell (MSC) therapy has shown promising results in the treatment of conditions ranging from liver cirrhosis to retinal damage, but results can be variable.

Oncotarget Characterization of iPS87, a prostate cancer stem cell-like cell line
Oncotarget Volume 11, Issue 12 reported outside its natural niche, the cultured prostate cancer stem cells lost their tumor-inducing capability and stem cell marker expression after approximately 8 transfers at a 1:3 split ratio.

Stem cell identity unmasked by single cell sequencing technology
Scientists from The University of Queensland's Diamantina Institute have revealed the difference between a stem cell and other blood vessel cells using gene-sequencing technology.

It's all about the (stem cell) neighborhood
Researchers at Duke-NUS Medical School have now identified how the stem cell neighbourhood, known as a niche, keeps stem cells in the gut alive.

Spaceflight activates cell changes with implications for stem cell-based heart repair
A new study of the effects of spaceflight on the development of heart cells identified changes in calcium signaling that could be used to develop stem cell-based therapies for cardiac repair.

Not just a stem cell marker
The protein CD34 is predominantly regarded as a marker of blood-forming stem cells but it helps with migration to the bone marrow too.

Interferon-beta producing stem cell-derived immune cell therapy on liver cancer
Induced pluripotent stem (iPS) cell-derived myeloid cells (iPS-ML) that produce the anti-tumor protein interferon-beta (IFN-beta) have been produced and analyzed by researchers from Kumamoto University, Japan.

Scientists aim to create the world's largest sickle cell disease stem cell library
Scientists at the Center for Regenerative Medicine at Boston Medical Center and Boston University School of Medicine are creating an induced pluripotent stem cell (iPSC)-based research library that opens the door to invaluable sickle cell disease research and novel therapy development.

Designer switches of cell fate could streamline stem cell biology
Researchers at the University of Wisconsin-Madison have developed a novel strategy to reprogram cells from one type to another in a more efficient and less biased manner than previous methods.

Allen Institute for cell science releases gene edited human stem cell lines
The Allen Institute for Cell Science has released the Allen Cell Collection: the first publicly available collection of gene edited, fluorescently tagged human induced pluripotent stem cells that target key cellular structures with unprecedented clarity.

Read More: Stem Cell News and Stem Cell Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to