Monday, November 26, 2007

TB’s Fighting Back!!

Tuberculosis… we’ve all heard of it. Many have thought it may have been cured, but it has made a comeback into today’s health headlines. Tuberculosis is a respiratory bacterial infection, but can also sometimes attack the central nervous system among other areas of the body. The bacterium that causes tuberculosis is called Mycobacterium tuberculosis and is bacillus in morphology and tests weakly positive in a Gram stain. It is highly infective as it only needs a cough or a sneeze from an infected person to transmit the bacterium. After the discovery of successful antibiotics, the number of incidences of being diagnosed with Tuberculosis dropped dramatically. Consistent use of antibiotics, in combination with an unsuccessful eradication program has caused new strains of Tuberculosis to emerge. A recent program by the World Health Organization to halt Tuberculosis has resulted in an “extensively” resistant strain to antibiotics.

Researchers tracked the developing drug resistance of one particular strain of Mycobacterium tuberculosis over 12 years. They found that at the time of the 2001 adoption of the DOT+ strategy for multi-drug resistant strains, the strain was already resistant to one or more of the drugs mandated by that strategy, thus allowing the strain to survive and develop resistance to additional drugs.

The continued use of antibiotics is not the answer to defeating the disease. The development of new treatment strategies may be what would be required to be able to continually battle the emergence of the now drug resistant stains of tuberculosis. The “discovery of copper-repressing protein in bacterium” may be a new strategy to defeat this disease.

Scientists have known that when macrophages - the host's immune cells - swallow an invading bacterium, they dump excessive amounts of copper onto the invader in an effort to kill it. While all cells need copper to function, too much of the metal ion causes cell death.

"But the invaders fight back with their own defense," says Adel Talaat, a microbiologist at the University of Wisconsin-Madison School of Veterinary Medicine. "They block the excess copper."

As this may hopefully be a new way to fight bacterial infections, of not only tuberculosis, the question now is how to trick the bacterium to forgo the mechanisms that prevent excessive uptake of copper.

Sources:

http://en.wikipedia.org/wiki/Tuberculosis

http://www.sciencedaily.com/releases/2007/10/071022120253.htm

http://www.who.int/mediacentre/factsheets/fs104/en/

http://www.sciencedaily.com/releases/2006/09/060915202534.htm

http://www.sciencedaily.com/releases/2006/12/061214084423.htm

Image Sources:

http://medicineworld.org/images/blogs/mycobacterium-tuberculosis-299290.jpg

1 comment:

Dominic B. said...

Everytime we try to trick a bacteria it willadapt...it has done that for millions of years. Bacteria were here WAYYYY before we were here....they will remain WAYYYY after we are all gone! Are we EVER going to learn that?