Antibodies trick bacteria into killing each other

Nov 14, 2011

The dominant theory about antibodies is that they directly target and kill disease-causing organisms. In a surprising twist, researchers from the Albert Einstein College of Medicine have discovered that certain antibodies to Streptococcus pneumoniae actually trick the bacteria into killing each other.

Pneumococcal vaccines currently in use today target the pneumococcal capsular (PPS), a sort of armor that surrounds the bacterial cell, protecting it from destruction. Current thought hold that PPS-binding antibodies protect against by inducing opsonic killing, a process in which pathogens are coated with a substance called opsonin, marking the pathogen out for destruction by the immune system.

While such antibodies are an important part of how protect against disease, there are PPS-specific antibodies that do not promote opsonic killing but are protective nonetheless.

In the study, Masahide Yano and his colleagues identify one of mechanisms these non-opsonic antibodies use. They increase the rate of communication between the as well as competence-induced killing, or fratricide, where the bacteria naturally kill each other off because of overconcentration.

"These findings reveal a novel, previously unsuspected mechanism by which certain PPS-specific antibodies exert a direct effect on pneumococcal biology that has broad implications for bacterial clearance, genetic exchange and antibody immunity to pneumococcus," says Yano.

Explore further: Understanding how cells follow electric fields

More information: Antibodies to Streptococcus pneumoniae Capsular Polysaccharide Enhance Pneumococcal Quorum Sensing, 13 September 2011 mBio vol. 2 no. 5 e00176-11. doi: 10.1128/​mBio.00176-11

Related Stories

New insights could lead to a better pneumococcal vaccine

Sep 22, 2008

Discovery of a new, previously unknown mechanism of immunity suggests that there may be a better way to protect vulnerable children and adults against Streptococcus pneumoniae (pneumococcal) infection, say researchers at ...

New pneumococcal vaccine approach successful in early tests

Feb 16, 2011

Pneumococcus (Streptococcus pneumoniae) accounts for as much as 11 percent of mortality in young children worldwide. While successful vaccines like Prevnar® exist, they are expensive and only work against specific pneumo ...

How meningitis bacteria attack the brain

Aug 18, 2009

(PhysOrg.com) -- A specific protein on the surface of a common bacterial pathogen allows the bacteria to leave the bloodstream and enter the brain, initiating the deadly infection known as meningitis. The new finding, which ...

Recommended for you

Understanding how cells follow electric fields

15 hours ago

Many living things can respond to electric fields, either moving or using them to detect prey or enemies. Weak electric fields may be important growth and development, and in wound healing: it's known that ...

Protein scaffold

May 27, 2015

Right before a cell starts to divide to give birth to a daughter cell, its biochemical machinery unwinds the chromosomes and copies the millions of protein sequences comprising the cell's DNA, which is packaged ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.