Autoimmunity and immunoadsorption
Autoantibodies are a type of antibody that mistakenly attacks the body’s own cells and tissues instead of targeting harmful invaders like bacteria or viruses. This autoimmune activity is hypothesised to play a role in long COVID and ME/CFS (although there is debate).
Immunoadsorption is a medical treatment that removes specific antibodies, including autoantibodies, from the bloodstream. Blood is drawn from the patient, filtered to selectively eliminate these antibodies, and then returned to the body.
Investigating the autoimmune hypothesis
Researchers at Charité University Hospital in Berlin have suggested that autoimmunity highlight evidence that autoantibodies – including those targeting β-adrenergic and muscarinic acetylcholine receptors – may be involved in the pathophysiology (underlying disease processes)of long COVID and ME/CFS.
To test the autoimmunity hypothesis, the study recruited 20 patients with post-COVID ME/CFS (individuals with long COVID who meet the Canadian Consensus Criteria for ME/CFS) who had elevated β2-adrenergic autoantibodies. These participants underwent five immunoadsorption sessions to remove these autoantibodies.
Findings
At the six months, the majority of participants reported clinical improvements in multiple domains, including: “fatigue, post-exertional malaise, pain, cognitive, autonomic, and immunological symptoms” and also in handgrip strength. The researchers concluded that the observed improvements support the hypothesis that autoantibodies contribute to ME/CFS and long COVID in some patients.
However, not all participants showed significant clinical improvement. The study also had limitations, including a small sample size, lack of a control group, and patient-reported outcomes. Acknowledging these factors, the researchers emphasised the need for further investigation. Furthermore, it would be interesting to see the results of longer-term follow-up.
Conclusion
The researchers suggest that immunoadsorption may lead to rapid clinical improvement in a subset of patients but emphasise that further trials are necessary to confirm their findings. The team is currently conducting randomised controlled trials with larger sample sizes to better assess the effectiveness of immunoadsorption in treating post-COVID ME/CFS.
The study ” serves as proof of concept for the initiation of clinical trials using drugs specifically designed to target autoantibodies.”
