Scientist - News - 17-04-2009:
Modified lactic acid bacteria as an anti-allergy vehicle
Beintema, Nienke
Probiotic bacteria are a promising candidate for treating auto-immune and allergic disorders. When genetically modified to produce certain proteins, lactic acid bacteriaproved to induce specific immune tolerance.
Genetically modified Lactococcus lactis that secrete the protein ovalbumin inside the gut can induce immune tolerance against this protein in mice that are allergic to it. This was the conclusion of Inge Huibregtse, researcher at the Amsterdam Medical Center (AMC), who successfully defended her PhD thesis on April 15.
Ovalbumin is a protein present in many foods, such as eggs. Many people are hypersensitive or even allergic to it. An allergic reaction occurs when the body’s immune system overreacts to certain substances that are in fact harmless. The immune system, designed to fight off pathogens, might turn to these substances by producing high amounts of immune factors. These may cause irritation and inflammation. The same is the case in so-called auto-immune reactions, in which the immune system reacts against the body’s own tissues. This hyperactive immune system is also involved in gasterointestinal disorders such as inflammatory bowel disease (IBD)
Regulated immune reaction
The immune reaction can be modulated by substances that trigger the immune system in a regulated way. This same principle lies at the basis of vaccination. Huibregtse and colleagues at the AMC, the University of Ghent (Belgium) and the Flemish Institute of Biotechnology (VIB) used this principle to design a treatment against ovalbumin hypersensitivity. The same idea, they say, also applies in other disorders such as IBD.
The researchers inserted a gene for ovalbumin production into the DNA of L. lactis. This allowed for production of this protein inside the gut. In this way the researchers addressed the common problem of how to effectively administer a certain drug in the right place.
When testing their method in mice that were hypersensitive to ovalbumin, they found that the modified bacterium induced specific ovalbumin tolerance in these mice through changes in their immune system: the mice produced more interleukin-10 and less interferon gamma.
The acceptance of genetically modified organisms is still generally low, and clinical application may be years away. Nonetheless, the researchers expressed optimism that this strategy can be developed further for the treatment of allergic and auto-immune disorders.
More information:
AMC press release 2009
Article by Huibregtse in Clinical Immunology (2007)
Article by Huibregtse in Gasteroenterology (2007)
VIB press release 2007
«BackModified lactic acid bacteria as an anti-allergy vehicle
Beintema, Nienke
Probiotic bacteria are a promising candidate for treating auto-immune and allergic disorders. When genetically modified to produce certain proteins, lactic acid bacteriaproved to induce specific immune tolerance.Genetically modified Lactococcus lactis that secrete the protein ovalbumin inside the gut can induce immune tolerance against this protein in mice that are allergic to it. This was the conclusion of Inge Huibregtse, researcher at the Amsterdam Medical Center (AMC), who successfully defended her PhD thesis on April 15.
Ovalbumin is a protein present in many foods, such as eggs. Many people are hypersensitive or even allergic to it. An allergic reaction occurs when the body’s immune system overreacts to certain substances that are in fact harmless. The immune system, designed to fight off pathogens, might turn to these substances by producing high amounts of immune factors. These may cause irritation and inflammation. The same is the case in so-called auto-immune reactions, in which the immune system reacts against the body’s own tissues. This hyperactive immune system is also involved in gasterointestinal disorders such as inflammatory bowel disease (IBD)
Regulated immune reaction
The immune reaction can be modulated by substances that trigger the immune system in a regulated way. This same principle lies at the basis of vaccination. Huibregtse and colleagues at the AMC, the University of Ghent (Belgium) and the Flemish Institute of Biotechnology (VIB) used this principle to design a treatment against ovalbumin hypersensitivity. The same idea, they say, also applies in other disorders such as IBD.
The researchers inserted a gene for ovalbumin production into the DNA of L. lactis. This allowed for production of this protein inside the gut. In this way the researchers addressed the common problem of how to effectively administer a certain drug in the right place.
When testing their method in mice that were hypersensitive to ovalbumin, they found that the modified bacterium induced specific ovalbumin tolerance in these mice through changes in their immune system: the mice produced more interleukin-10 and less interferon gamma.
The acceptance of genetically modified organisms is still generally low, and clinical application may be years away. Nonetheless, the researchers expressed optimism that this strategy can be developed further for the treatment of allergic and auto-immune disorders.
More information:
AMC press release 2009
Article by Huibregtse in Clinical Immunology (2007)
Article by Huibregtse in Gasteroenterology (2007)
VIB press release 2007