New research reveals shared immune dysfunction mechanisms in allergies and autoimmune diseases

Recent epidemiological studies and immunologic reviews demonstrate significant clinical overlap between allergic and autoimmune diseases, challenging the traditional binary view of immune dysfunction. Shared inflammatory pathways, genetic risks, and epithelial barrier damage caused by environmental toxins disrupt immune tolerance and microbiome stability. These findings are driving cross-category drug repurposing, including interleukin-5 and Janus kinase inhibitors, while prompting clinicians to screen allergic patients for underlying autoimmune symptoms.

Shared biological mechanisms of allergies and autoimmunity

• ▪Disruptions in overlapping immune processes lead to a loss of immunological tolerance and misdirected inflammatory responses that can manifest as allergic or autoimmune conditions, according to immunologist Giuseppe Alvise Ramirez.
• ▪Allergic and autoimmune disorders share inflammatory signaling pathways, genetic susceptibilities, and mechanisms regulating immune tolerance, challenging the view that allergies involve only T-helper 2 responses and autoimmune diseases only T-helper 1 responses.

Studies linking allergic and autoimmune diseases

• ▪A 2025 systematic review and meta-analysis of 26 studies found a 49% higher hazard of autoimmune disease in patients with atopic dermatitis (hazard ratio 1.49, 95% CI 1.31-1.70).
• ▪A 2019 U.S. cross-sectional study found that 7.9% of adults and 2.0% of children with atopic dermatitis had an autoimmune disorder, compared to 5.7% of adults and 1.0% of children without atopic dermatitis.
• ▪A 2026 nationwide cohort study of over 269,000 South Korean adults associated allergic diseases with higher risks of six autoimmune conditions, including rheumatoid arthritis, Hashimoto's thyroiditis, Graves' disease, ankylosing spondylitis, ulcerative colitis, and systemic lupus erythematosus.

Observed clinical overlaps

• ▪Immunologist Giuseppe Alvise Ramirez highlighted food allergy and celiac disease as another example of allergic and autoimmune overlap affecting the gastrointestinal tract.
• ▪Patients with severe systemic lupus erythematosus frequently develop allergies and drug hypersensitivities during autoimmune flares, according to observations by immunologist Giuseppe Alvise Ramirez.

Epithelial barrier damage from environmental chemicals

• ▪Cezmi Akdis recommends reducing unnecessary contact with household cleaners, dishwasher detergents, and personal care products containing surfactants that damage epithelial barriers.
• ▪Exposure to everyday chemical substances like cleaning surfactants, air pollutants, microplastics, and food emulsifiers disrupts epithelial cell tight junctions, triggering persistent inflammation, according to Cezmi Akdis.
• ▪The epithelial barrier theory developed by Cezmi Akdis proposes that damage to protective cell layers in the skin, respiratory tract, and gastrointestinal system contributes to allergic and chronic inflammatory diseases.

Microbiome disruption on epithelial surfaces

• ▪Changes in microorganism communities inhabiting epithelial surfaces promote chronic inflammation and interfere with immune tolerance, according to Cezmi Akdis.
• ▪Environmental chemical exposures that damage epithelial barriers in the skin, respiratory tract, and gastrointestinal tract also affect the microbiome, according to research reviewed by Giuseppe Alvise Ramirez.

Therapeutic strategies targeting shared immune pathways

• ▪Restoring immune tolerance is emerging as a primary therapeutic focus for managing co-occurring allergic and autoimmune conditions, according to UCLA Health section chief Rita Kachru.
• ▪Identified overlaps in immune dysregulation have enabled the repurposing of medications between allergic and autoimmune conditions, including therapies targeting interleukin-5 and Janus kinase signaling.
• ▪Identifying shared immune biomarkers and dysregulation pathways is driving research into cellular and molecular immune-editing strategies, according to immunologist Giuseppe Alvise Ramirez.

Clinical practice and evaluation

• ▪Rita Kachru, section chief for clinical immunology and allergy at UCLA Health, frequently encounters patients with co-occurring allergic and autoimmune conditions in clinical practice.
• ▪Rita Kachru recommends that clinicians routinely evaluate allergic disease patients for autoimmune symptoms, including gastrointestinal issues, unexplained rashes, recurrent fevers, and photosensitivity.