Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Why Many Cells are Better than One

Limited decision-making ability of individual cells is bolstered in masses

Researchers from Johns Hopkins have quantified the number of possible decisions that an individual cell can make after receiving a cue from its environment, and surprisingly, it’s only two.

The first-of-its-kind study combines live-cell experiments and math to convert the inner workings of the cell decision-making process into a universal mathematical language, allowing information processing in cells to be compared with the computing power of machines.

The research published on September 15 in Science also demonstrates why it’s advantageous for cells to cooperate to overcome their meager individual decision-making abilities by forming multicellular organisms.

“Each cell interprets a signal from the environment in a different way, but if many cells join together, forming a common response, the result can eliminate the differences in the signal interpretation while emphasizing the common response features,” says Andre Levchenko, Ph.D., associate professor of biomedical engineering and member of the Institute for Cell Engineering. “If a single blood vessel cell gets a signal to contract, it is meaningless since all the surrounding cells in the blood vessel need to get the message to narrow the blood vessel. Cell collaboration does wonders in terms of their ability to transfer information and convert it into decision-making.”

One bit of information represents two choices: yes or no, on or off, or one or zero in binary code, used by computer programmers. Two bits doubles the amount of choices to four and so on for each bit added.

To determine how many bits of information a cell has for each decision, the researchers had to measure a real biological decision in progress. They decided to look at a well-known cell stimulant, a protein called tumor necrosis factor (TNF), responsible for turning on the inflammation response in the body. When cells detect TNF on their surface, they transmit a message that sends a messenger protein into the nucleus to turn on inflammation genes.

The researchers administered different amounts of TNF to mouse cells in dishes, and then they determined whether the messenger went to the nucleus. They bound the messenger with a glowing tag; the more messenger present in the nucleus, the brighter the nucleus would appear under a microscope. The researchers used a computer program to quantify the brightness of the nucleus after the addition of TNF. From this, they calculated a single cell’s response to be 0.92 bits of information, allowing for two possible decisions.

“What we get from this information is that the cell can only reliably detect the presence of the signal or not, nothing more precise,” says Levchenko. “This was a little bit dissatisfying because we were hoping that the cells could recognize many more levels of the input and use that to make more decisions than just two.”

The researchers tested other scenarios to see if cells could respond in more ways. They looked at decision outputs other than inflammation, like development and cell survival. They also looked to see if the cell’s response to a certain stimulus changed over time, as well as explored whether receiving different input signals that led to the same outcome could boost decision-making potential. None of these different situations drove cells to show greater decision-making ability. Cells seem to have distinct limits to the amount of information they intake that confines the number of decisions they can make, says Levchenko.

Finally, the researchers investigated the idea that cells could collectively respond to input to make decisions together. They went back to quantifying the brightness of the nucleus in response to TNF, but this time they examined clusters of cells and compiled this data into their equation. They found that clusters of as few as 14 cells could produce 1.8 bits of information, corresponding to somewhere from 3 to 4 different potential decisions for the cluster.

The fact that combinations of cells can make more decisions suggests why being multicellular is such a good thing in the animal world and why cells can sometimes achieve so much more if they are working together than separately, says Levchenko.

“We’ve learned that there is a clear limit on what can happen in a cell, and we are actually quantifying for the first time what the cells can and can’t do,” says Levchenko. “A lot of people were surprised that this was even possible. This framework we’ve laid will allow us to test what kind of tricks cells use, other than being multicellular, to expand their decision repertoire.”

The first author on the study, Raymond Cheong, was responsible for much of the experimental and theoretical analysis. Other researchers involved included Alex Rhee and Chiaochun Joanne Wang of Johns Hopkins and Ilya Nemenman of Emory University.

The study was supported by the National Institutes of Health, the Medical Scientist Training Program at Johns Hopkins and the Los Alamos National Laboratory Directed Research and Development Program.

Vanessa McMains | EurekAlert!
Further information:

More articles from Life Sciences:

nachricht Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München

nachricht Second research flight into zero gravity
21.10.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>