Featured Research

from universities, journals, and other organizations

Invertebrate Immune Systems Are Anything But Simple

Date:
June 22, 2007
Source:
European Science Foundation
Summary:
A hundred years since microbiologists first discovered the invertebrate immune system, they are just beginning to understand its complexity. Scientists recently discovered that invertebrates have evolved elaborate ways to fight disease.

The invertebrate immune system is anything but simple.
Credit: Image courtesy of European Science Foundation

A hundred years since Russian microbiologist Elie Metschnikow first discovered the invertebrate immune system, scientists are only just beginning to understand its complexity. Presenting their findings at a recent European Science Foundation (ESF) conference, scientists showed that invertebrates have evolved elaborate ways to fight disease.

By studying starfish, Metschnikow was the first to see cells digesting bacteria, a process he called phagocytosis (the eating of cells by other cells). Phagocytosis, it turns out, is an important immune defence in all living things. Since Metschnikow’s work, scientists have studied the immune systems of simpler organisms (such as invertebrates) in the hope of understanding the immune systems of more complex organisms, like us.

However, invertebrates’ immune systems are more elaborate than we expected. “We have underestimated the complexity of invertebrate immunity,” says Dr. Paul Schmid-Hempel, an evolutionary ecologist at the ETH Zurich in Switzerland. By studying the immune systems of fruit flies, mosquitoes and other invertebrates (including bed bugs, moths, crustaceans, worms, sponges and bees), scientists are finding new molecules involved in defences against pathogens (microbes that cause disease).

One molecule found in fruit flies, Dscam, is capable of folding itself in 18,000 different ways. Computer models that predict the structure of this molecule have led scientists to suggest that this folding creates different shapes, each capable of binding to different structures on the pathogen’s surface. “These molecules can be used very flexibly by assembling their components in many ways,” says Schmid-Hempel. Until now, this ability to recognize specific pathogens was thought to be limited to vertebrates.

In another exciting area of research, scientists showed the sophisticated ways that invertebrates manage their immune systems. “Insects recognise peptidoglycan [a component of bacterial cell wall] and this triggers a rapid immune response” explains Schmid-Hempel. However, once the bacteria have been killed, molecules digest peptidoglycans and therefore dampen down the immune response. Regulating the immune response in this way is important because immune systems, if left unchecked, can harm an individual by mistakenly attacking cells in the body.

In humans, the failure of the body to recognise itself results in autoimmune diseases. For example, Crohn’s disease is the failure of the body to recognize intestinal cells, resulting in an immune response against these cells. Understanding these autoimmune processes in invertebrates might help us to better engineer drugs to tackle these debilitating diseases in humans.

Insects can also boost their immune systems ready for a pathogen invasion. Female bedbugs, which are often wounded during mating, enhance their immune system prior to mating in anticipation of pathogen invasion. Similarly, bumblebees maintain their immune systems in an enhanced state following a pathogen attack to counter future infections. “This can even cross generations, with mothers transferring immunity to their offspring” says Schmid-Hempel. This delicate management of immune responses has until now been regarded as a characteristic of vertebrates.

Schmid-Hempel thinks that the molecular mechanisms found in invertebrate immune systems may rival those seen in the vertebrate world. He says: “Insects use different cells and molecules, but follow very similar principles for detecting pathogens as vertebrates.”

And scientists are only beginning to understand the elaborate ways that invertebrates respond to pathogens. As they discover new molecules, the invertebrate immune system could turn out to be much more like that of vertebrates — making it an even better model for the study of our own immune system.


Story Source:

The above story is based on materials provided by European Science Foundation. Note: Materials may be edited for content and length.


Cite This Page:

European Science Foundation. "Invertebrate Immune Systems Are Anything But Simple." ScienceDaily. ScienceDaily, 22 June 2007. <www.sciencedaily.com/releases/2007/06/070621102626.htm>.
European Science Foundation. (2007, June 22). Invertebrate Immune Systems Are Anything But Simple. ScienceDaily. Retrieved April 24, 2014 from www.sciencedaily.com/releases/2007/06/070621102626.htm
European Science Foundation. "Invertebrate Immune Systems Are Anything But Simple." ScienceDaily. www.sciencedaily.com/releases/2007/06/070621102626.htm (accessed April 24, 2014).

Share This



More Plants & Animals News

Thursday, April 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Monkeys Are Better At Math Than We Thought, Study Shows

Monkeys Are Better At Math Than We Thought, Study Shows

Newsy (Apr. 23, 2014) A Harvard University study suggests monkeys can use symbols to perform basic math calculations. Video provided by Newsy
Powered by NewsLook.com
Raw: Leopard Bites Man in India

Raw: Leopard Bites Man in India

AP (Apr. 22, 2014) A leopard caused panic in the city of Chandrapur on Monday when it sprung from the roof of a house and charged at rescue workers. (April 22) Video provided by AP
Powered by NewsLook.com
Iowa College Finds Beauty in Bulldogs

Iowa College Finds Beauty in Bulldogs

AP (Apr. 22, 2014) Drake University hosts 35th annual Beautiful Bulldog Contest. (April 21) Video provided by AP
Powered by NewsLook.com
805-Pound Shark Caught Off The Coast Of Florida

805-Pound Shark Caught Off The Coast Of Florida

Newsy (Apr. 22, 2014) One Florida fisherman caught a 805-pound shark off the coast of Florida earlier this month. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins