Cow milk allergy occurs in children and in adults.
Scientists at Messerli Research Institute at the Vetmeduni Vienna, the Medical University of Vienna, and the University of Vienna investigated what actually makes the milk allergenic. A specific protein in milk known as beta-lactoglobulin is able to initiate an allergy only when being devoid of iron.
Loaded with iron, the protein is harmless. The scientists discovered the same mechanism recently with regard to birch pollen allergy. Their findings help to decipher allergic reactions and were published in the journal PLOS ONE.
Milk allergy is frequently confused with lactose intolerance. However, these are two entirely different mechanisms that occur in the body. People with lactose intolerance do not digest lactose properly because they lack an enzyme known as lactase. In the case of the potentially much more dangerous cow milk allergy, however, the body's immune system attacks milk proteins with its own IgE antibodies.
According to statistics, about two to three percent of children in Europe suffer from a genuine milk allergy. Less adults are diagnosed with the disease. The formation of so-called Th2 lymphocytes is initiated in these patients. Th2 lymphocytes contribute in great measure to the production of IgE antibodies to milk proteins. Hence, people develop an allergic reaction to milk.
Such an allergy may cause swelling of the mouth and mucous membranes, diarrhea, exacerbation of neurodermitis, and in rare cases even an allergic shock. Precise diagnostic investigation helps to differentiate between allergy and intolerance and thus avoid incorrect diets which, under certain circumstances, may cause malnutrition.
Lack of iron load transforms milk protein into allergen
One of the most important milk allergens, the so-called beta-lactoglobulin, belongs to the protein family of lipocalins. Lipocalins possess molecular pockets which are able to accommodate iron complexes. Iron is bound to the protein by so-called siderophores. The first author Franziska Roth-Walter and her colleagues now show that an "empty" milk protein, one without iron and siderophores, helps to activate Th2 lymphocytes. As a consequence, the production of IgE antibodies against the milk protein is stimulated. The patient gets sensitized and may develop an allergic reaction to milk. Roth-Walter, working at the department of Comparative Medicine at the Messerli Research Institute says: "Knowledge of the molecular structure of allergens has contributed very significantly to our conclusion about milk allergy. This is of enormous practical relevance."
Investigating the difference between organic and conventional milk
As the next step the scientists want to find out, what contributes to the iron load of milk proteins. The lead investigator Erika Jensen-Jarolim explains: "One of the most burning questions we want to answer is: Why are these milk proteins loaded to a greater or lesser extent with iron? The manner of keeping and feeding cows may be a factor involved in this phenomenon. Iron loading may depend on whether the milk is produced organically or conventionally. This will be one of our major interests in the future. Lipocalins exist in all mammals. We assume that our conclusions will be applicable to the milk of other mammals as well."
The article „The major cow milk allergen Bos d 5 manipulates T-helper cells depending on its load with siderophore-bound iron”, by Franziska Roth-Walter, Luis. F. Pacios, Cristina Gomez-Casado, Gerlinde Hofstetter, Georg A. Roth, Josef Singer, Araceli Diaz-Perales and Erika Jensen-Jarolim was published on the 12th of August in the journal PLOS ONE. DOI: 10.1371/journal.pone.0104803
About the Messerli Research Institute
The Messerli Research Institute was founded in 2010 with support from the Messerli Foundation (Sörenberg, Switzerland) under the management of the University of Veterinary Medicine, Vienna in cooperation with the Medical University of Vienna and the University of Vienna. Its research is devoted to the interaction between humans and animals, as well as its theoretical principles in animal cognition and behavior, comparative medicine and ethics. http://www.vetmeduni.ac.at/messerli
About the University of Veterinary Medicine, Vienna
The University of Veterinary Medicine, Vienna in Austria is one of the leading academic and research institutions in the field of Veterinary Sciences in Europe. About 1,200 employees and 2,300 students work on the campus in the north of Vienna which also houses five university clinics and various research sites. Outside of Vienna the university operates Teaching and Research Farms. http://www.vetmeduni.ac.at
Prof. Erika Jensen-Jarolim
Messerli Research Institute
University of Veterinary Medicine Vienna
Medical University Vienna
Science Communication / Public Relations
University of Veterinary Medicine Vienna (Vetmeduni Vienna)
T +43 1 25077-1153
Dr. Susanna Kautschitsch | idw - Informationsdienst Wissenschaft
Gene switch may repair DNA and prevent cancer
12.02.2016 | Institute for Integrated Cell-Material Sciences at Kyoto University
New method opens crystal clear views of biomolecules
11.02.2016 | Deutsches Elektronen-Synchrotron DESY
Today, plants and microorganisms are heavily used for the production of medicinal products. The production of biopharmaceuticals in plants, also referred to as “Molecular Pharming”, represents a continuously growing field of plant biotechnology. Preferred host organisms include yeast and crop plants, such as maize and potato – plants with high demands. With the help of a special algal strain, the research team of Prof. Ralph Bock at the Max Planck Institute of Molecular Plant Physiology in Potsdam strives to develop a more efficient and resource-saving system for the production of medicines and vaccines. They tested its practicality by synthesizing a component of a potential AIDS vaccine.
The use of plants and microorganisms to produce pharmaceuticals is nothing new. In 1982, bacteria were genetically modified to produce human insulin, a drug...
Atomic clock experts from the Physikalisch-Technische Bundesanstalt (PTB) are the first research group in the world to have built an optical single-ion clock which attains an accuracy which had only been predicted theoretically so far. Their optical ytterbium clock achieved a relative systematic measurement uncertainty of 3 E-18. The results have been published in the current issue of the scientific journal "Physical Review Letters".
Atomic clock experts from the Physikalisch-Technische Bundesanstalt (PTB) are the first research group in the world to have built an optical single-ion clock...
The University of Würzburg has two new space projects in the pipeline which are concerned with the observation of planets and autonomous fault correction aboard satellites. The German Federal Ministry of Economic Affairs and Energy funds the projects with around 1.6 million euros.
Detecting tornadoes that sweep across Mars. Discovering meteors that fall to Earth. Investigating strange lightning that flashes from Earth's atmosphere into...
Physicists from Saarland University and the ESPCI in Paris have shown how liquids on solid surfaces can be made to slide over the surface a bit like a bobsleigh on ice. The key is to apply a coating at the boundary between the liquid and the surface that induces the liquid to slip. This results in an increase in the average flow velocity of the liquid and its throughput. This was demonstrated by studying the behaviour of droplets on surfaces with different coatings as they evolved into the equilibrium state. The results could prove useful in optimizing industrial processes, such as the extrusion of plastics.
The study has been published in the respected academic journal PNAS (Proceedings of the National Academy of Sciences of the United States of America).
Exceeding critical temperature limits in the Southern Ocean may cause the collapse of ice sheets and a sharp rise in sea levels
A future warming of the Southern Ocean caused by rising greenhouse gas concentrations in the atmosphere may severely disrupt the stability of the West...
12.02.2016 | Event News
09.02.2016 | Event News
02.02.2016 | Event News
12.02.2016 | Physics and Astronomy
12.02.2016 | Life Sciences
12.02.2016 | Medical Engineering