Gert van der Hoek
In Memoriam - Editor, Senior Moderator
Tuberculosis causes 1.7 million deaths annually, the number is growing every year.
Also a growing number of TB-patients with MDR-TB or XDR-TB (= drugresistant).
A real "superbug".
About one-third of the world's population has been exposed or infected with the TB bacteria,
but only 10% of these people with latent TB become ill with the active form of the disease.
This study seems to be an important step to develop a test to find out if you belong to the 10%.
Scientists Move Closer To Blood Test That Predicts TB Using Genetic Signature
Article Date: 19 Aug 2010
Some snips
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Scientists have moved a step closer to developing a blood test that one day will be able to predict which 10 per cent of people who carry the TB bacterium in a latent form will later go on to have the full blown disease: they have identified clusters of genes or a "transcriptional signature" in patients with latent TB that is also carried by people with the active disease.
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There are two forms of TB: latent and active. People with the latent form of the disease carry the bacterium but don't develop symptoms, in fact only 10 per cent of people with the latent form will go on to develop the active form. The active disease attacks mainly the lungs, but TB bacteria can also attack any part of the body such as the kidney, spine, and brain.
Unfortunately, our immune response to the bacterium is not straightforward and difficult to characterize. This is what has been holding back the development of new diagnostics, treatments and vaccines. It appears that susceptibility to the disease is not a matter of one or two genes, but clusters of genes, and maybe even relationships between those clusters, controlled by whether certain genes are switched on or off.
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So currently, while we can test whether people carry the TB bacterium, we can't tell which of the 1 in 10 carriers is likely to progress to active disease.
-
They found that one particular blood-based signature, the "neutrophil-driven interferon (IFN)-inducible gene profile", was the strongest link between people with latent TB and those with active disease, and this "reverted back to that of healthy controls after treatment".
They also found that a subset of this signature discriminated active TB from other inflammatory and infectious diseases, and that while an "IFN-inducible signature was also observed in whole blood of patients with systemic lupus erythematosus (SLE), their complete modular signature differed from TB".
They concluded that their study had found a hitherto unappreciated role for the type of signalling this signature controls in the development of TB and this could be important for developing new vaccines and treatments.
-
"If you could predict which so-called carriers of TB will progress to the full-blown disease, this would have major ramifications for stopping the global epidemic."
"We just have to prove it now, but it's very promising,"
http://www.medicalnewstoday.com/articles/198254.php
Also a growing number of TB-patients with MDR-TB or XDR-TB (= drugresistant).
A real "superbug".
About one-third of the world's population has been exposed or infected with the TB bacteria,
but only 10% of these people with latent TB become ill with the active form of the disease.
This study seems to be an important step to develop a test to find out if you belong to the 10%.
Scientists Move Closer To Blood Test That Predicts TB Using Genetic Signature
Article Date: 19 Aug 2010
Some snips
-
Scientists have moved a step closer to developing a blood test that one day will be able to predict which 10 per cent of people who carry the TB bacterium in a latent form will later go on to have the full blown disease: they have identified clusters of genes or a "transcriptional signature" in patients with latent TB that is also carried by people with the active disease.
-
There are two forms of TB: latent and active. People with the latent form of the disease carry the bacterium but don't develop symptoms, in fact only 10 per cent of people with the latent form will go on to develop the active form. The active disease attacks mainly the lungs, but TB bacteria can also attack any part of the body such as the kidney, spine, and brain.
Unfortunately, our immune response to the bacterium is not straightforward and difficult to characterize. This is what has been holding back the development of new diagnostics, treatments and vaccines. It appears that susceptibility to the disease is not a matter of one or two genes, but clusters of genes, and maybe even relationships between those clusters, controlled by whether certain genes are switched on or off.
-
So currently, while we can test whether people carry the TB bacterium, we can't tell which of the 1 in 10 carriers is likely to progress to active disease.
-
They found that one particular blood-based signature, the "neutrophil-driven interferon (IFN)-inducible gene profile", was the strongest link between people with latent TB and those with active disease, and this "reverted back to that of healthy controls after treatment".
They also found that a subset of this signature discriminated active TB from other inflammatory and infectious diseases, and that while an "IFN-inducible signature was also observed in whole blood of patients with systemic lupus erythematosus (SLE), their complete modular signature differed from TB".
They concluded that their study had found a hitherto unappreciated role for the type of signalling this signature controls in the development of TB and this could be important for developing new vaccines and treatments.
-
"If you could predict which so-called carriers of TB will progress to the full-blown disease, this would have major ramifications for stopping the global epidemic."
"We just have to prove it now, but it's very promising,"
http://www.medicalnewstoday.com/articles/198254.php
