Navigation Links
Human cells exhibit foraging behavior like amoebae and bacteria
Date:3/11/2010

When cells move about in the body, they follow a complex pattern similar to that which amoebae and bacteria use when searching for food, a team of Vanderbilt researchers have found.

The discovery has a practical value for drug development: Incorporating this basic behavior into computer simulations of biological processes that involve cell migration, such as embryo development, bone remodeling, wound healing, infection and tumor growth, should improve the accuracy with which these models can predict the effectiveness of untested therapies for related disorders, the researchers say.

"As far as we can tell, this is the first time this type of behavior has been reported in cells that are part of a larger organism," says Peter T. Cummings, John R. Hall Professor of Chemical Engineering, who directed the study that is described in the March 10 issue of the Public Library of Science journal PLoS ONE.

The discovery was the unanticipated result of a study the Cummings group conducted to test the hypothesis that the freedom with which different cancer cells move a concept called motility could be correlated with their aggressiveness: That is, the faster a given type of cancer cell can move through the body the more aggressive it is.

"Our results refute that hypothesisthe correlation between motility and aggressiveness that we found among three different types of cancer cells was very weak," Cummings says. "In the process, however, we began noticing that the cell movements were unexpectedly complicated."

Then the researchers' interest was piqued by a paper that appeared in the February 2008 issue of the journal Nature titled, "Scaling laws of marine predator search behaviour." The paper contained an analysis of the movements of a variety of radio-tagged marine predators, including sharks, sea turtles and penguins. The authors found that the predators used a foraging strategy very close to a specialized random walk pattern, called a Lvy walk, an optimal method for searching complex landscapes. At the end of the paper's abstract they wrote, "Lvy-like behaviour seems to be widespread among diverse organisms, from microbes to humans, as a 'rule' that evolved in response to patchy resource distributions."

This gave Cummings and his colleagues a new perspective on the cell movements that they were observing in the microscope. They adopted the basic assumption that when mammalian cells migrate they face problems, such as efficiently finding randomly distributed targets like nutrients and growth factors, that are analogous to those faced by single-celled organisms foraging for food.

With this perspective in mind, Alka Potdar, now a post-doctoral fellow at Case Western Reserve University and the Cleveland Clinic, cultured cells from three human mammary epithelial cell lines on two-dimensional plastic plates and tracked the cell motions for two-hour periods in a "random migration" environment free of any directional chemical signals. Epithelial cells are found throughout the body lining organs and covering external surfaces. They move relatively slowly, at about a micron per minute which corresponds to two thousandths of an inch per hour.

When Potdar carefully analyzed these cell movements, she found that they all followed the same pattern. However, it was not the Lvy walk that they expected, but a closely related search pattern called a bimodal correlated random walk (BCRW). This is a two-phase movement: a run phase in which the cell travels primarily in one direction and a re-orientation phase in which it stays in place and reorganizes itself internally to move in a new direction.

In subsequent studies, currently in press, the researchers have found that several other cell types (social amoeba, neutrophils, fibrosarcoma) also follow the same pattern in random migration conditions. They have also found that the cells continue to follow this same basic pattern when a directional chemical signal is added, but the length of their runs are varied and the range of directions they follow are narrowed giving them a net movement in the direction indicated by the signal.

"For the first time, this gives us a general framework for analyzing the way cells move," says Potdar.


'/>"/>

Contact: David F. Salisbury
david.salisbury@vanderbilt.edu
615-343-6803
Vanderbilt University
Source:Eurekalert

Related biology news :

1. Students perceptions of Earths age influence acceptance of human evolution, says U of Minn. study
2. Way to go: MBL scientists identify driving forces in human cell division
3. Musk ox population decline due to climate, not to humans, study finds
4. Study shows potential for using algae to produce human therapeutic proteins
5. Recently analyzed fossil was not human ancestor as claimed, anthropologists say
6. If bonobo Kanzi can point as humans do, what other similarities can rearing reveal?
7. New University of Colorado paper shows novel way to study human inflammatory disease
8. Intelligent people have unnatural preferences and values that are novel in human evolution
9. The carbon cycle before humans
10. A common thread links multiple human cognitive disorders
11. Human use heel first gait because it is efficient for walking
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/26/2016)... DUBLIN , April 27, 2016 ... of the  "Global Multi-modal Biometrics Market 2016-2020"  report ... ) , The analysts forecast ... a CAGR of 15.49% during the period 2016-2020.  ... a number of sectors such as the healthcare, ...
(Date:4/15/2016)... , April 15, 2016 ... "Global Gait Biometrics Market 2016-2020,"  report to their ... ) , ,The global gait biometrics market ... 13.98% during the period 2016-2020. Gait ... which can be used to compute factors that ...
(Date:3/31/2016)... 31, 2016   ... the "Company") LegacyXChange is excited to release ... soon to be launched online site for trading 100% ... ) will also provide potential shareholders a sense of ... to an industry that is notorious for fraud. The ...
Breaking Biology News(10 mins):
(Date:5/23/2016)... ... May 23, 2016 , ... PrecisionAg® Media ... in 2017 and Beyond. The paper outlines the key trends that are creating ... , “We’ve witnessed a lot of highs and lows as the precision agriculture ...
(Date:5/23/2016)... May 23, 2016 - Leading CRO,s Use ... - Frontage Implement a Single Platform to Manage End-to-end Operations ... Within the Bioanalytical lab Frontage Laboratories, a full-service contract ... and China , has selected IDBS, ... In addition to serving as the global electronic lab notebook (ELN), ...
(Date:5/22/2016)... (PRWEB) , ... May 22, 2016 , ... Doctors in ... in combating the asbestos cancer, malignant mesothelioma. Surviving Mesothelioma has just posted an article ... in the University of Rome’s Department of Clinical Sciences and Translational Medicine evaluated more ...
(Date:5/20/2016)... ... ... Korean researchers say Manumycin A triggers apoptosis, or natural cell death, in ... disease. Surviving Mesothelioma has just posted an article on the new study. Click ... mesothelioma study on the fact the Manumycin A, a derivative of Streptomyces parvulus, is ...
Breaking Biology Technology: