Microbiome Composition Influences Autoantibody Development in Lupus
People with lupus produce autoantibodies causing the body to attack itself and promoting inflammation and tissue damage. A new research study divided people with lupus into two cohorts, or groups, so they could identify key differences. One group consisted of first-degree relatives (FDRs) without lupus and healthy people, and their molecular profiles were compared against a second group, which consisted of unrelated people with and without lupus.
The researchers found elevated plasma levels of lupus-related autoantibodies in both people with the disease and their FDRs compared to healthy people. They noted that FDRs with a parent or child relationship with a person with lupus had elevated plasma levels compared to healthy people and siblings of people with lupus, which has not been shown previously.
Additionally, they discovered a direct correlation between levels of microbial translocation (MT) (a driver of immune activation) and plasma autoantibodies in FDRs and found differences in the circulating microbiome composition of people with lupus and their FDRs compared to healthy people.
“There is increasing evidence that the interactions between our immune systems and the bacteria in our gastrointestinal system is important in a number of diseases including lupus. This paper demonstrates that the more bacterial products that get through the gut lining into the blood circulation, the more autoantibodies are found in the blood. This being more in first degree relatives of lupus patients than control subjects suggests that there may be shared genetic or environmental factors that impact how leaky our guts are,” said Dr. Gary Gilkeson, study author and professor of medicine at the Medical University of South Carolina.
The study results indicate that microbial products from the gut mucosa into the circulation may play a role in autoantibody development and immune suppressive therapy may affect this association. Further investigation is needed to establish causality. Learn about the genetics of lupus.