Immune hematology

Research led by the Centenary Institute in Sydney has found a brand new target for treating drug-resistant tuberculosis; our scientists have uncovered that the tuberculosis bacterium hijacks platelets from the body’s blood clotting system to weaken our immune systems. Tuberculosis is far from eradicated around the world and still infects more than 1,400 people per year in Australia. Antibiotic resistant tuberculosis is particularly deadly and expensive to treat; costing up to $250,000 to treat a single case in Australia.

Increasing the effectiveness

Scientists at the Centenary Institute have been working on new ways to treat tuberculosis by increasing the effectiveness of the immune system. Using the zebrafish model of tuberculosis, the researchers used fluorescent microscopy to observe the build-up of clots and activation of platelets around sites of infection. Because Senior author and head of the Centenary’s Immune Vascular Interactions laboratory, Dr. Stefan Oehlers, says “the zebrafish gives us literal insight into disease processes by watching cells interacting in real time”.

Following their hunch that these platelets are being tricked by the infection into getting in the way of the body’s immune system; the researchers treated infections with anti-platelet drugs, including widely available aspirin; and were able to prevent hijacking and allow the body to control infection better.

Immune-Vascular Interactions

Dr. Elinor Hortle; lead author of the paper published in The Journal of Infectious Diseases; and Research Officer in Centenary’s Immune-Vascular Interactions laboratory says “This is the first time that platelets are find to worsen tuberculosis in an animal model. It opens up the possibility that anti-platelet drugs could be used to help the immune system fight off drug resistant TB”.

There are over 1.2 million Australians living with latent tuberculosis, a non-infectious form of TB that puts them at risk of developing the active disease. “Our study provides more crucial evidence that widely available aspirin could be used to treat patients with severe tuberculosis infection and save lives;” says Dr. Hortle.

Complicated as pathogens

An immune system is a collection of biological processes within an organism that protects against disease by identifying and killing pathogens and tumour cells. Because  It detects a wide variety of agents, from viruses to parasitic worms; and needs to distinguish them from the organism’s own healthy cells and tissues in order to function properly. Therefore Detection is complicate as pathogens can evolve rapidly; therefore producing adaptations that avoid the immune system and allow the pathogens to successfully infect their hosts.
To survive this challenge, multiple mechanisms evolved that recognize and neutralize pathogens. Even simple unicellular organisms such as bacteria possess enzyme systems that protect against viral infections. Other basic immune mechanisms evolved in ancient eukaryotes and remain in their modern descendants, such as plants, fish, reptiles; and insects.
These mechanisms include antimicrobial peptides called defensins, phagocytosis, and the complement system. Vertebrates such as humans have even more sophisticated defense mechanisms. Because The immune systems of vertebrates consist of many types of proteins, cells, organs, and tissues; which interact in an elaborate and dynamic network.