Scientists have identified novel biomarkers that may help design a new rheumatoid arthritis treatment, even predicting the condition before it develops.
A new study, published in Scientific Reports, and led by researchers from Washington State University and Arthritis Northwest in Spokane, may help to advance rheumatoid arthritis treatment. The team found that cells from a cheek swab taken from a woman with rheumatoid arthritis revealed new biomarkers for the disease.
The epimutations of the cells – which are molecular factors and processes around DNA that regulate genome activity, independent of DNA sequence – were distinct from those without the joint-damaging autoimmune disease.
The team believes that their findings will help further rheumatoid arthritis treatment, combatting the condition before its symptoms persist.
Micheal Skinner, the senior author of the study from Washington State University’s School of Biological Sciences, said: “If we can identify these patients ten years earlier before the disease develops, it opens up a whole arena of preventative medicine that we did not have access to before.”
Rheumatoid arthritis treatment limitations
In the US alone, around 200,00 people are affected by rheumatoid arthritis annually, with the disease being more prevalent in women than in men. However, current rheumatoid arthritis treatment has limited efficacy in many patients who have already developed the disease. Previous research demonstrates that patients who are administered treatment in the early stages of the disease can cause remission of the symptoms.
Skinner said: “Having biomarkers could allow treatment to begin even earlier before the first signs of it start.”
Biomarker discovery
The team collected cheek cells – otherwise known as buccal cells – using a swab from two cohorts of women—one group of 26 caucasian women from Spokane and a group of 23 African-American women from Los Angeles. Half of the women in each group had rheumatoid arthritis, while the others served as a control.
Despite them being taken from the cheek, the buccal cells enabled the researchers to do an epigenome-wide analysis. The epigenome consists of chemical factors that can modify the genome and change its behaviour, and although it is not part of the DNA itself, epimutations can still be passed down through subsequent generations.
The team discovered epimutations in areas called DNA methylation regions in both groups of women who had rheumatoid arthritis. Although previous research had illustrated that African-Americans showed signs of an increased prevalence of rheumatoid arthritis, the team observed a large overlap in epimutations among both races, meaning the biomarkers hold a strong signal for the disease.
Skinner commented: “Surprisingly, most of the DNA methylation sites we found that were consistent among patients with the disease were associated with genes previously known to be involved in rheumatoid arthritis.
“The findings add to evidence that the disease is likely systemic, meaning it was found not just in immune system cells involved in rheumatoid arthritis development but in many different cells throughout the body.”
Additionally, the team tested an immune-related monocyte cell type in the blood samples from both sets of women, but the buccal cells also showed epimutations as well, meaning a relatively non-invasive diagnostic cheek swab test could be developed to screen for the disease.