The very mention of Salmonella evokes fear amongst consumers in the western world because of the disease potential of this bacterial species that has caused hundreds of incidences of product recall and thousands of consumers falling ill due to contamination of foods like meat, frozen food, spinach, egg, poultry, tomato etc. According to a recent report, world wide about 2 lakh people are infected with Salmonella with less than 0.02% dying out of the episode. Most famous strains are S.typhi responsible for typhoid fever and S.paratyphi causing paratyphoid fever amongst humans. These vectors are especially dangerous to children, old age people and immune compromised consumers. It is inconceivable that Salmonella can be useful to man in any way but if recent research findings are to be believed the bacteria can help overcoming some forms of cancer at early stages. The SipA protein present in the cell of this bacteria can generate caspase-3 enzyme in the human body which can contribute to programmed death of cancerous cells in human body..
"Salmonella uses an enzyme, known as caspase-3, produced by the infected host cell, to deliberately increase inflammation at the site of infection. Normally, caspase-3 plays an important role in the body by removing damaged or malfunctioning cells from the system through a process known as 'programmed cell death' or apoptosis. It is this process of cell death that is often defective in cancerous cells. The researchers, Dónal Wall from the University of Glasgow, and Srikanth Chittur and Beth McCormick from the University of Massachusetts Medical School, demonstrated that the salmonella bacterial protein SipA is responsible for inducing caspase-3 activation within the host cell. "The novelty of the research is in understanding how the bacteria are undermining the host cell, and getting it [host cells] to process the bacterial toxins into smaller functional units," said Wall. The bacteria deliver large toxins into the cell and then use the host enzyme, caspase-3, to divide these proteins. These toxins can then go to different parts of the cell to carry out their individual functions." Caspase-3 only cuts specific sequences within proteins (bacterial toxins) known as caspase-3 cleavage sites. Notably, caspase-3 cleavage sites are found in several salmonella proteins; however, these appear to be restricted to proteins that play a role in bacterial entry, or proteins that are used to overpower the host cell, indicating that this may be a general strategy employed by the bacteria to aid with processing bacterial toxins. "Although this work is important for the field of host-pathogen interactions it also highlights a process that could be exploited in cancer therapeutics to activate programmed cell death in cells in which the early stages of this process are defective."
Though the findings show the potential for the use of Salmonella cells in treating cancer, there are logistical problems in delivering the live cells to the affected site in the patient and its subsequent inactivation to pre-empt any undesirable consequences due to their presence in the body. Further studies are needed to develop delivery techniques that can bring the cancer cells and the live bacteria together for achieving the desired result.
http://vhpotty.blogspot.com/
http://foodtechupdates.blogspot.com
No comments:
Post a Comment