Dutch company Merck Animal Health embarked on the development of new vaccination strategies to protect against bovine mastitis by signing an agreement with the Department of Medical Microbiology of the University Medical Center Utrecht and the Faculty of Veterinary Medicine of Utrecht University in the Netherlands, Merck reported today. The project, titled “Evasion Molecules in Bovine Mastitis Vaccines” (EVAC), aims to develop a series of vaccines against difficult-to-treat infections with certain bacteria known to cause bovine mastitis, such as Staphylococcus aureu, Streptococcus uberis and Escheria coli. Development of vaccines against bovine mastitis have been hampered due to the relevant pathogens’ creation of “immune evasion molecules” that block or interfere with important processes in the immune system of the cow, Merck said. Evasion molecules also appear to interfere with the immune response that is provoked against vaccines. Therefore, despite the induction of high antibody levels, the clinical efficacy of most mastitis vaccines developed so far have been poor, Merck said. Through the EVAC project, 25 of the 50 evasion molecules have been identified and characterized, and recombinant versions of the proteins have been produced. Combinations of such evasion molecules will be added to traditional antigens in candidate vaccines. Merck expects these vaccines to raise the neutralizing antibodies against immune evasion molecules in the animal, leading the evasion system of the bacteria to become impaired and allowing the antibodies to neutralize the mastitis-causing pathogens. The EVAC project is part of the Alternatives for Antibiotics (ALTANT) program, coordinated by public-private research consortium Immuno Valley. The technologies developed within the ALTANT program may result in an efficacious vaccine against bovine mastitis and, in combination with current therapeutic tools, can result in unprecedented possibilities to control the disease, according to Rene Aerts, Ph.D., vice president of global biological research and development at Merck Animal Health. <HOME>
