Autoimmune Responses in COVID-19 Patients

The emergence of autoimmune phenomena during and after SARS-CoV-2 infection has been recognised as a significant contributor to disease severity and long-term complications. Patients with COVID-19 develop a complex autoantibody repertoire directed against host antigens including angiotensin-converting enzyme 2, cytokines, phospholipid-binding proteins and G protein-coupled receptors. The breadth of this response ranges from transient elevations of natural autoantibodies to persistent new-onset specificities that remain detectable a year or more after acute illness. Age-related immunosenescence, epitope cross-reactivity with viral proteins and dysregulated immune regulation underpin this phenomenon, leading to thrombotic events, organ dysfunction and neuropsychiatric sequelae. Detailed epitope mapping has revealed molecular mimicry between viral surface proteins and self-antigens, suggesting direct mechanisms of autoimmunity. Ongoing research is refining the clinical and mechanistic links between specific autoantibodies and the spectrum of post-COVID-19 conditions, with important implications for diagnostics, risk stratification and potential immunomodulatory therapies.

Research from Nature Portfolio

Recent studies have mapped the dynamics of new-onset autoantibodies in cohorts of mild and severe COVID-19 patients, demonstrating that a wide range of autoantibodies emerge following infection and persist for at least twelve months. Epitope mapping techniques have identified sequence similarities between key viral fusion peptides and host antigens, supporting a molecular mimicry model for post-infectious autoimmunity. Parallel investigations into autoantibodies against ACE2, chemokines and cytokines have shown elevated levels in individuals with severe disease, with specific immunoglobulin subclasses targeting epitopes near the catalytic domain of ACE2 and proinflammatory cytokines. Furthermore, autoantibodies against G protein-coupled receptors and renin–angiotensin system-related molecules such as CXCR3 and AGTR1 correlate strongly with clinical severity, and alterations in autoantibody network patterns appear predictive of disease progression.

Autoimmune Responses in COVID-19 Patients publication trend

The graph below shows the total number of articles in autoimmune responses in covid-19 patients across all publications each year (not limited to Nature Index journals).

Technical terms

Autoantibody: An antibody directed against the body’s own proteins or antigens.

Epitope: The specific region of an antigen recognised by an antibody.

Molecular mimicry: Sequence or structural similarity between foreign and self-antigens that can trigger autoimmunity.

Immunosenescence: Age-related decline and remodelling of the immune system’s function.

Antiphospholipid antibodies: Autoantibodies targeting phospholipids or phospholipid-binding proteins, associated with thrombotic disorders.

References

1. Prevalent and persistent new-onset autoantibodies in mild to severe COVID-19. Nature Communications (2024).
2. Autoantibodies to ACE2 and immune molecules are associated with COVID-19 disease severity. Communications Medicine (2024).
3. Severe COVID-19 patients exhibit elevated levels of autoantibodies targeting cardiolipin and platelet glycoprotein with age: a systems biology approach. npj Aging (2023).
4. Prothrombotic autoantibodies in serum from patients hospitalized with COVID-19. Science Translational Medicine (2020).
5. Reaction of Human Monoclonal Antibodies to SARS-CoV-2 Proteins With Tissue Antigens: Implications for Autoimmune Diseases. Frontiers in Immunology (2021).
6. Autoantibodies targeting GPCRs and RAS-related molecules associate with COVID-19 severity. Nature Communications (2022).