SYDNEY, Feb. 15 (Xinhua) -- Australian researchers on Friday said they have uncovered genetic mutations in cells behind autoimmune disease, pointing to significant implications for the diagnosis and treatment of the major medical condition.
"Current treatments for autoimmune disease address only the symptoms, but not the cause. To make more targeted treatments that address disease development and progression, we first need to understand the cause," Professor Chris Goodnow, executive director of the Garvan Institute of Medical Research and director of the University of New South Wales (UNSW) Sydney Cellular Genomics Futures Institute, said in a statement.
"We have developed a technique that allows us to look directly at the cells that cause autoimmune disease - it's as though we're looking through a new microscope lens for the first time, learning more about autoimmune disease than was ever possible before."
A team led by researchers at the Garvan Institute pinpointed individual cells that cause autoimmune disease from patient samples and uncovered how the cells "go rogue" by evading checkpoints that normally stop immune cells from targeting the body's own tissues, according to the institute.
The findings "could have significant implications for the diagnosis and treatment of autoimmune disease, which affects one in eight individuals in Australia", it said.
Because "rogue" immune cells are so rare in a blood sample -- less than one in 400 cells -- studying them has been a challenge and analysis to date "has at best revealed 'averages' of the vast mix of cells in a patient's sample", said Dr. Mandeep Singh, first author of the findings published in the Cell medical journal.
"Using cellular genomics, we developed a method to 'zoom in' on these disease-causing immune cells in the blood samples of four patients with cryoglobulinemic vasculitis - a severe inflammation of the blood vessels," Singh said.
By separating individual cells and their genetic material, the researchers isolated immune cells producing antibody proteins that target healthy tissues in the body and are associated with the most common autoimmune diseases, including rheumatoid arthritis.
Once isolated, the researchers analyzed the "rogue" cells, scanning more than a million positions in the genome to identify DNA variants that may be at the root of disease, according to the institute.
The research findings uncovered the root cause of an autoimmune disease and "the ability to identify and investigate specific immune cells at such resolution has vast potential for future treatments to target the cause of all autoimmune diseases", it said.
"In our study, we uncovered specific mutations that mark early stages of autoimmune disease. If we can diagnose a patient at these stages, it may be possible to combine our knowledge of these mutations with new targeted treatments for lymphoma to intervene in disease progression or to track how well a patient is responding to treatments," said the study's co-senior author Dr. Joanne Reed, who heads the rheumatology and autoimmunity group at the Garvan Institute.
The researchers are now planning follow-up studies to investigate mutations of autoimmune cells in a range of other diseases, including lupus, celiac disease and type 1 diabetes.
"Identifying these rogue immune cells is a significant step forward for how we study autoimmune disease - and crucially the first step to finding ways to eliminate them from the body entirely," Goodnow said.
