TB, Tuberculosis - Current Affairs Questions and Answers

1)   Indian researchers saw reduction in TB bacteria using phytochemical bergenin extracted from which tree?

a. Sakhua
b. Shala
c. Shorea robusta
d. Only a and b are same
e. All 3 of the above are the same
Answer  Explanation 

ANSWER: Only a and b are same

A team of Indian researchers achieved a 100-fold reduction in tuberculosis bacteria load in lungs of mice after 60 days of treatment using bergenin.

Bergenin is a phytochemical isolated from tender leaves of sakhua or shala tree (Shorea robusta). Unlike the regularly used antibiotic drugs that target the TB bacteria, the bergenin compound modulates the immune system to kill the bacteria found inside the macrophages, which is a type of white blood cells.

The study conducted by the Indian researchers show that the bergenin compound can be used to clear the bacteria.

In fact, when it is used in combination with other TB drugs, the compound can produce good results.

The researchers undertook several studies to understand the mode of action of the compound.

The compound was unable to directly kill tuberculosis bacteria when treated with the compound.

However, in the case of in vitro studies, the compound was able to kill the bacteria found inside infected cells.

In mice infected with TB and treated with the compound, there was significant reduction in the bacterial load in the lungs.

Unlike in the case of in vitro studies, in mice the compound was found to activate not only the macrophages but also other cell types (T cells) that led to effective killing of the bacteria.

A significant reduction in the number of granulomatic lesions was seen in animals treated with the compound.

Also, the bacterial load was 100-fold lower in mice treated with the compound compared with animals that were not treated with bergenin.

The bergenin compound was selectively enhancing the frequency of interferon-gamma and interleukin-17-producing T cells in the TB infected animals.

Interferon-gamma promotes bacteria-killing nitric oxide inside macrophages thus promoting the generation of protective immune responses against tuberculosis bacteria.

The compound can be used in patients with drug-resistant TB too, as it does not target the bacteria directly but modulates the immune system to kill the bacteria.

2)   A novel mechanism of a protein secreted by_______________, inhibiting the infected host’s immune response by modulating certain genes has been discovered, giving rise to hopes of a targeted drug therapy.

a. Mycobacterium tuberculosis (Mtb)
b. Sycobacterium tuberculosis (Stb)
c. Tycobacterium tuberculosis (Ttb)
d. Lycobacterium tuberculosis (Ltb)
Answer  Explanation 

ANSWER: Mycobacterium tuberculosis (Mtb)

With identification of suitable drug targets and candidate vaccines to control TB remaining a challenge and most of the studies focusing on strategies to prevent TB infection, scientists from the Centre for DNA Fingerprinting and Diagnostics here have looked at the interaction between pathogenic mycobacteria and the human cell during infection to develop a new form of targeted drug therapy. The discovery could not only be a potential drug target against mycobacterial infections but also help in developing a new biomarker for identification of M tuberculosis infection in humans.