Thymic stromal lymphopoietin (TSLP) is a natural substance produced by the body, playing a role in the immune system. TSLP antibodies are specialized proteins designed to specifically target and neutralize TSLP’s effects in the body.
Understanding TSLP’s Role
TSLP is a cytokine primarily released by epithelial cells in barrier tissues such as the skin, lungs, and gut. It acts as an “alarmin,” released in response to triggers like allergens, viruses, pollutants, or tissue injury. This release signals the immune system.
Once released, TSLP interacts with a specific receptor complex on immune cells, including dendritic cells, T cells, and basophils. This interaction influences immune responses. TSLP drives type 2 inflammation, a common feature in allergic and inflammatory diseases, and its overactivity is linked to their development.
How TSLP Antibodies Work
TSLP antibodies are monoclonal antibodies. These engineered proteins specifically bind to TSLP in the body. By binding to TSLP, these antibodies prevent it from attaching to its receptor complex on immune cells.
This blockade effectively disrupts the signaling pathways that TSLP would normally activate. Consequently, the downstream inflammatory responses that contribute to symptoms in certain diseases are reduced. For example, blocking TSLP can lessen the activation of dendritic cells, which in turn reduces the production of certain inflammatory cytokines like IL-4, IL-5, and IL-13.
Therapeutic Uses of TSLP Antibodies
TSLP antibodies are used or investigated for several medical conditions where TSLP’s overactivity contributes to disease. A primary application is in the treatment of severe asthma, particularly for patients whose condition remains uncontrolled despite other therapies. Tezepelumab (TEZSPIRE) is an approved TSLP antibody for this use. It is the only biologic approved for severe asthma without limitations based on specific biomarkers like eosinophil counts or allergic status.
Tezepelumab has shown effectiveness in reducing asthma exacerbations and improving lung function across a broad range of severe asthma phenotypes, including eosinophilic, allergic, and type 2-low asthma. Clinical trials have demonstrated significant reductions in annualized asthma exacerbation rates, ranging from 63-71% in eosinophilic severe asthma and 34-49% in type 2-low asthma. This broad applicability distinguishes it from other biologics that target more specific downstream mediators of inflammation.
TSLP antibodies are also being investigated for other allergic and inflammatory conditions. These include atopic dermatitis (eczema), chronic rhinosinusitis with nasal polyps, chronic obstructive pulmonary disease, and eosinophilic esophagitis. The upstream action of TSLP antibodies makes them promising candidates for various conditions driven by type 2 inflammation.
What to Know About TSLP Antibody Treatment
TSLP antibody treatments, such as Tezepelumab, are administered by injection, typically once every four weeks. This medication is an add-on maintenance therapy, used in conjunction with other standard treatments to manage chronic conditions. It is not a cure but rather a tool to help control symptoms and reduce disease activity.
Patients considering TSLP antibody treatment should understand it is part of a broader, ongoing treatment plan. Common side effects are generally mild and may include injection site reactions such as redness, swelling, or pain. Other reported side effects include upper respiratory tract infections, nasopharyngitis (inflammation of the nasal passages and throat), and headaches. These reactions often resolve on their own.