Navigation Links
Blame the environment: Why vaccines may be ineffective for some people

A new discovery may explain why a tuberculosis vaccine is not as effective for some people as anticipated, and potentially explains why other vaccines do not work as well for some as they do for others. In a research report presented in the December 2010 issue of the Journal of Leukocyte Biology (, scientists from Singapore show that Mycobacterium chelonae, a common environmental bacterium found in soil and water, can decrease the effectiveness of the bacille Calmette-Guerin (BCG) vaccine used to prevent tuberculosis, especially in countries outside of the United States.

"Uncovering the reasons why BCG is failing will help researchers in designing new, more effective vaccines against TB," said Geok Teng Seah, Ph.D., a researcher involved in the work from the Department of Microbiology at the National University of Singapore. "This will give us more tools to fight this globally significant infectious disease."

To make this discovery, scientists studied mice with and without prior exposure to M. chelonae. When subsequently given BCG vaccine, the mice with prior exposure to M. chelonae produced higher amounts of suppressive chemical signals; these chemical signals are believed to reduce the level of immunity induced by BCG vaccine in the host mice. Then the researchers extracted certain white blood cells with known suppressive functions from both exposed and unexposed mice. After transferring these cells into separate groups of unexposed mice, they found that recipients of suppressor cells from M. chelonae exposed mice did not respond as strongly to BCG vaccine as recipients of suppressor cells from unexposed donor mice. This indicates that the suppressor cells from M. chelonae exposed mice are functionally different from those of unexposed mice. Ultimately, the data suggest that these suppressor cells, induced in the host when exposed to M. chelonae, dampen the effectiveness of the BCG vaccine.

"This study sheds important light on why many immunological therapies and vaccines look great in the lab, but fall short in the real world," said John Wherry, Ph.D., Deputy Editor of the Journal of Leukocyte Biology. "Humans are exposed to many more non-disease causing bacteria and viruses compared to relatively clean laboratory animals, and as this study shows with a TB vaccine, environmental exposure to one kind of bacteria can influence the efficacy of immunity to different, more dangerous bugs."


Contact: Cody Mooneyhan
Federation of American Societies for Experimental Biology

Related biology news :

1. Lacking Finance Education to Blame for Rising Insolvency?
2. Dont blame cities for climate change, see them as solutions
3. Discovery in legumes could reduce fertilizer use, aid environment: Stanford researchers
4. Cow vaccines go vroom
5. Scientists use computer algorithms to develop seasonal flu vaccines
6. New bacterial signaling molecule could lead to improved vaccines
7. Prescription drug could boost effects of vaccines for HIV and other diseases
8. Vaccines preventing pneumococcal disease protect African children with sickle-cell disease
9. GEN reports on the promise of DNA vaccines
10. Major breakthrough may pave the way for therapeutic vaccines
11. Bug barcode readers hold out promise of universal vaccines
Post Your Comments:
(Date:6/16/2016)... 2016 The global ... reach USD 1.83 billion by 2024, according to ... Technological proliferation and increasing demand in commercial buildings, ... drive the market growth.      (Logo: ... development of advanced multimodal techniques for biometric authentication ...
(Date:6/9/2016)... innovation leader in attendance control systems is proud to announce the introduction of fingerprint ... sure the right employees are actually signing in, and to even control the opening ... ... ... Photo ...
(Date:6/7/2016)... TORONTO , June 7, 2016  Syngrafii ... begun a business relationship that includes integrating Syngrafii,s ... pilot branch project. This collaboration will result in ... for the credit union, while maintaining existing document ... ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... ... 2016 , ... While the majority of commercial spectrophotometers and fluorometers use the ... models are higher end machines that use the more unconventional z-dimension of 20mm. ... the bottom of the cuvette holder. , FireflySci has developed several Agilent flow ...
(Date:6/23/2016)... , June 23, 2016 /PRNewswire/ - FACIT ... Ontario biotechnology company, Propellon Therapeutics ... development and commercialization of a portfolio of first-in-class ... Epigenetic targets such as WDR5 represent an exciting ... significantly in precision medicine for cancer patients. Substantial ...
(Date:6/23/2016)... 23, 2016  The Biodesign Challenge (BDC), a university ... to harness living systems and biotechnology, announced its winning ... New York City . ... showcased projects at MoMA,s Celeste Bartos Theater during the ... MoMA,s senior curator of architecture and design, and ...
(Date:6/23/2016)... , June 23, 2016 Apellis ... Phase 1 clinical trials of its complement C3 ... single and multiple ascending dose studies designed to ... (PD) of subcutaneous injection in healthy adult volunteers. ... (SC) either as a single dose (ranging from ...
Breaking Biology Technology: