BIOLOGICS IN DEPTH
Biologics are used to restore the immune system’s ability to fight infections and disease.1 A better understanding on how an overactive immune system causes atopic dermatitis can help you better appreciate the role of biologics in managing your condition.2-4
Flare-ups and Your Immune System
Atopic dermatitis is a result of Type 2 inflammation.2
When your immune system responds to threats, this results in inflammation.2 There are three types of inflammatory responses, depending on what your immune system is reacting against.2 Each type of response uses different immune cells and specific chemical signals.2
A Type 1 inflammatory response is used to fight viruses, cancer cells, and bacteria that invade cells.2 Your immune system uses Type 2 inflammatory responses for allergens and parasites, while Type 3 responses are for fungi and bacteria that do not invade cells.2
In atopic dermatitis, allergens or irritants trigger an overactive Type 2 inflammatory immune response, resulting in flare-ups and symptoms.2
Type 2 inflammation is also seen in other allergic diseases, like asthma and allergic rhinitis.2 So it’s possible for one person to have two or more of these diseases at the same time.2
Chemical Signals and the Itch-Scratch Cycle
IL-4 and IL-13 are important chemical signals in atopic dermatitis.2
Type 2 immune responses use several different chemical signals that result in inflammation.2 These chemical signals are one of the targets for biological therapy.
In atopic dermatitis, it is believed that two important chemical signals of Type 2 immune proteins called IL-4 and IL-13 are present in every stage of the disease.2 Both IL-4 and IL-13 may contribute to the symptoms in several ways.2-4
Increased levels of IL-4 contributes to allergic inflammation, promoting allergic antibodies and helping attract the cells responsible for the allergic immune response.4
IL-13 enhances the itch sensation,3 prompting the urge to scratch, helping perpetuate the itch-scratch cycle.
Both IL-4 and IL-13 may also affect the ability of the skin to block irritants and infections.3, 4 IL-13 in particular could weaken the skin barrier, allowing more irritants and germs to enter, thereby resulting in more inflammation.3
In addition to IL-4 and IL-13, there are several other chemical signals that are possibly involved in atopic dermatitis, which are under investigation.2, 4 These pieces of information increase our understanding of the disease, potentially giving doctors and patients more options for treatment.
How Biologics Help in Atopic Dermatitis
Biological therapies may be used to target the overactive immune system, by blocking some of the processes and signals that underlie the disease.1, 4
Biologics can be used to target Type 2 Inflammation.1, 2, 4
Biologics that may be useful for the treatment of atopic dermatitis are designed to block the actions of the chemical signals involved in the disease process.2, 4 Potential goals of such therapy include reducing the underlying inflammation, decreasing symptoms, helping break the itch-scratch cycle, and reducing flare-ups.2, 4
Research into the use of biologics for patients with moderate to severe atopic dermatitis have revealed quite promising results.2. 4 Studies have shown significant improvement in some patients in terms of sustained decrease in itchiness and other symptoms.2. 4
However, as with any other treatment, there are some potential side effects.2, 4 It’s important to discuss the pros and cons with a professional health expert before starting with any new medication.
- Stöppler, M.C. “Biological Therapy”, Balentine, J.R. (Editor), MedicineNet. https://www.medicinenet.com/biological_therapy/article.htm#what_is_biological_therapy (Accessed October 28, 2020).
- Maurer, M. & Wittmann, M. (2020). Type 2 inflammation in atopic dermatitis and beyond: shared pathophysiology and clinical management. In Maurer, M. (chair), ADVENT medical education symposium, European Academy of Allergy and Clinical Immunology (EAACI) Digital Congress 2020. https://www.emjreviews.com/allergy-immunology/symposium/type-2-inflammation-in-atopic-dermatitis-and-beyond-shared-pathophysiology-and-clinical-management/
- Furue, M., Ulzii, D., Nakahara, T., et al. (2020). Implications of IL-13Rα2 in atopic skin inflammation. Allergology International, 69(3), 412-416. https://www.sciencedirect.com/science/article/pii/S1323893020300113
- Deleanu, D. & Nedelea, I. (2019). Biological therapies for atopic dermatitis, an update. Exp Ther Med, 17(2), 1061-1067. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6327672/
Health information contained herein is provided for general educational purposes only. Your healthcare professional is the single best source of information regarding your health. Please consult your healthcare professional if you have any questions about your health or treatment.