Nav: Home

Discovering the early age immune response in foals

June 29, 2017

Researchers at the Cornell University College of Veterinary Medicine have discovered a new method to measure tiny amounts of antibodies in foals, a finding described in the May 16 issue of PLOS ONE.

The methodology will help understand how fast a foal starts producing its own antibodies, which in turn will help optimize recommendations for young horse vaccination schedules, said Dr. Julia Felippe, associate professor of large animal medicine, and research associate Rebecca Tallmadge.

Newborn horses are initially protected against diseases by antibodies they receive after birth through the colostrum produced by their dam. Vaccination is an important strategy to protect neonates against diseases. However, administrating vaccines too early in life may have negative effects. Vaccines work by presenting the immune system with a killed pathogen (or a protein from it) that will "train" the body to recognize it as an intruder. If the immune system of the young animal is not ready, instead of recognizing the pathogen's protein in the vaccine as foreign, it may identify it as "self" and impair the production of an immune response against this particular pathogen. Additionally, the mother's antibodies may interfere with the neonate's antibody production, making the vaccine ineffective. To develop a protective vaccination strategy, it is crucial to understand how young animals become immunocompetent.

Monitoring the development of the neonatal immune system using traditional methods, such as an antibody count in the foal's blood, is hampered by the abundance of maternal antibodies relative to the young's own. The maternal antibodies wear off progressively as the young animal ages, but this may take a few months depending on the half-life of the different antibodies. Current guidelines recommend vaccination of foals to start at 3 months or at 6 months of age if the dam was vaccinated in late gestation.

"We presume that if the mother is vaccinated in her last month of pregnancy, her antibodies will transfer to the foal, but in reality we don't measure the efficiency of this process," said Felippe. Previous work led Felippe and Tallmadge to believe that the foal immune system could respond to vaccines very early in life, and the team decided to test this hypothesis. They vaccinated 3-day-old foals, gave them boosters at 21 and 35 days, and followed the foals' immune response up to 42 days after birth.

To overcome the challenge of counting antibodies in such young foals, Felippe and Tallmadge examined the foals' B cells, the cells that create antibodies. This allowed them to examine the foal's immune response alone, independent of maternal circulating antibodies. Additionally, B cells take up to 10 days before releasing the antibodies they created. "After they find a match for the antibody, B cells adjust and tweak their antibody to make a perfect fit for the pathogen," says Felippe. "They are amazing, they are like little factories." The DNA changes that occur in the B cells' maturation process can thus be tracked through time by sequencing their DNA. As the researchers gave boosters to the foals, they observed an increase in the diversity of mutations in the B cell DNA as those immune cells kept looking for a better fit to the antigen. "Testing antigen-specific B cells gave us beautiful responses," said Tallmadge. This suggests that foals start producing antibodies in the first days when vaccinated. Yet results were different depending on the type of vaccine.

"Our results suggested that some vaccines may induce higher production of antibodies than others," said Felippe. "However, our experiment was not designed to measure efficacy of certain vaccines." Rather, its aim was to explore the neonate's immune response almost in real time, and with more sensitivity, without confounding circulating maternal antibodies.

"Our approach can be applied to any vaccine or pathogen in any host species," said Tallmadge. After showing that neonates are capable of an immune response, the researchers now want to see if there are neonate-specific mechanisms designed to prevent this response.

"The reason why such a mechanism would exist is, imagine you live in the womb, very protected, and now you are out in the environment with billions of pathogens poking you for an immune response. If you respond to every stimulus with the same intensity at the same time, something might happen with you," said Felippe. "So, there may be something out there that prevents you from damaging yourself in this process and prioritizes a response to a stimulus that is relevant."
-end-


Cornell University

Related Immune System Articles:

Immune system upgrade
Theoretically, our immune system could detect and kill cancer cells.
Using the immune system as a defence against cancer
Research published today in the British Journal of Cancer has found that a naturally occurring molecule and a component of the immune system that can successfully target and kill cancer cells, can also encourage immunity against cancer resurgence.
First impressions go a long way in the immune system
An algorithm that predicts the immune response to a pathogen could lead to early diagnosis for such diseases as tuberculosis
Filming how our immune system kill bacteria
To kill bacteria in the blood, our immune system relies on nanomachines that can open deadly holes in their targets.
Putting the break on our immune system's response
Researchers have discovered how a tiny molecule known as miR-132 acts as a 'handbrake' on our immune system -- helping us fight infection.
Decoding the human immune system
For the first time ever, researchers are comprehensively sequencing the human immune system, which is billions of times larger than the human genome.
Masterswitch discovered in body's immune system
Scientists have discovered a critical part of the body's immune system with potentially major implications for the treatment of some of the most devastating diseases affecting humans.
How a fungus can cripple the immune system
An international research team led by Professor Oliver Werz of Friedrich Schiller University, Jena, has now discovered how the fungus knocks out the immune defenses, enabling a potentially fatal fungal infection to develop.
How the immune system protects us against bowel cancer
Researchers from Charité - Universitätsmedizin Berlin have discovered a protective mechanism which is used by the body to protect intestinal stem cells from turning cancerous.
How herpesviruses shape the immune system
DZIF scientists at the Helmholtz Zentrum München have developed an analytic method that can very precisely detect viral infections using immune responses.
More Immune System News and Immune System Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

Accessing Better Health
Essential health care is a right, not a privilege ... or is it? This hour, TED speakers explore how we can give everyone access to a healthier way of life, despite who you are or where you live. Guests include physician Raj Panjabi, former NYC health commissioner Mary Bassett, researcher Michael Hendryx, and neuroscientist Rachel Wurzman.
Now Playing: Science for the People

#544 Prosperity Without Growth
The societies we live in are organised around growth, objects, and driving forward a constantly expanding economy as benchmarks of success and prosperity. But this growing consumption at all costs is at odds with our understanding of what our planet can support. How do we lower the environmental impact of economic activity? How do we redefine success and prosperity separate from GDP, which politicians and governments have focused on for decades? We speak with ecological economist Tim Jackson, Professor of Sustainable Development at the University of Surrey, Director of the Centre for the Understanding of Sustainable Propserity, and author of...
Now Playing: Radiolab

An Announcement from Radiolab