A unique line of chickens could help lead to better prevention methods and treatment for vitiligo, an autoimmune disease in humans.
“The chicken models for autoimmune diseases are natural carriers of autoimmune diseases. They develop the diseases spontaneously, without genetic manipulation or induction of the autoimmune responses. These diseases are multifactorial, so you have to have a genetic component and an environmental trigger for the disease to develop,” said Gisela Erf, professor of immunology with the University of Arkansas System Division of Agriculture through its research arm, the Arkansas Agricultural Experiment Station and author of a recent study on the subject published in Frontiers in Immunology.
Vitiligo, which is found in 1-2% of the world’s population, affects skin pigment, resulting in white patches of skin over the human body. The disease is also associated with autoimmune thyroiditis.
The Smyth line of chickens is currently the only animal model that accurately displays all the symptoms of vitiligo, which makes it critical for research on this and other human autoimmune diseases.
“When it comes to autoimmunity and some aspects of cell-mediated immunity, the chicken is actually more similar to the human than the mouse,” she added. “Here, you have a real opportunity to determine the processes involved in the development of the disease.”
Although laboratory rats and mice are the most common animal models used in biomedical research, research involving chickens has also resulted in breakthroughs in medical research. One example of this is the use of chicken eggs to study how medications could affect children with cancer.
‘A living test-tube’
Erf has developed an easier method to measure and analyze immune cell activity in chickens.
To study immune responses to injected vaccines and other therapeutics, she uses the “pulp” of small growing feathers. This skin test site, which is unique to birds, functions as “a living test-tube,” requiring only minimally invasive procedures for biopsy and laboratory analysis.
“We take blood samples along with collecting the feather samples, so now we have a dual window where we can look at cellular responses at the site of the injection and at inflammatory responses in the blood, as well as the antibody response,” said Erf.
This technique is promising for furthering the understanding of immune responses in both poultry and people.
Industry support needed
Poultry industry support is vital for research on the Smyth and other chicken genetic lines to continue, Erf said, stressing the importance that someone champion these chicken lines.
Right now, when researchers retire, they rely upon other researchers to continue caring for live bird populations or on preservation technology that is still in its infancy. Restarting a chicken line requires years of careful breeding.
“It’s a labor of love to keep these populations alive and do the genetic selection and really pay attention to the phenotype that’s maintained,” she concluded.
