Aptamer-based inhibition of the chemokines CCL17 and CCL22 in allergic and inflammatory reactions
Biological and Biomimetic Chemistry
Final Report Abstract
The chemokines C-C motif chemokine ligand 17 (CCL17) and C-C motif chemokine ligand 22 (CCL22) are ligands of the C-C motif chemokine receptor 4 (CCR4). They are mainly secreted by dendritic cells (DC) and macrophages to recruit CCR4-expressing T cells in physiological processes, and notably during diseases including skin allergies like allergic contact dermatitis (ACD). We could show that mice genetically deficient for CCL17 and CCL22 have ameliorated allergic symptoms in contact hypersensitivity (CHS), the mouse model for ACD. Furthermore, we report that aptamers recognizing either CCL17 or CCL22 can inhibit chemokine-dependent migration and supress allergic symptoms in the CHS model. In a series of experiments the duration of action of the CCL17-specific aptamer MF35.47m, the time of administration and the perseverance of its suppressive effects in CHS were assessed. Whereas aptamer application 24 h post allergen challenge still led to amelioration of ear swelling, the reduction of T cell immigration into the skin was not as effective as aptamer application closer to the time of challenge. A pre-challenge application of aptamer was most effective when applied 1 h before challenge suggesting a duration of action of 12 – 24 h in vivo. However, the suppressive effects of MF35.47m did not last for a second allergen challenge. In addition to the CCL17- specific aptamer MF35.47, manual and automated in vitro selection procedures, also referred to as SELEX (Systematic Evolution of Ligands by Exponential enrichment) were performed to generate CCL22-specific aptamers. Out of eight possible CCL22-specific aptamer candidates we selected one for modification, in vitro and in vivo tests, based on its high specificity, affinity and ability to suppress CCL22-dependent T cell migration. Injection of this aptamer called AJ102.29m during a CHS, at the time of the allergen challenge and 12 h post challenge, led to an efficient amelioration of allergic symptoms in vivo, and, importantly, did not induce undesired Toll-like receptor activation. With the prospect of developing a therapeutic treatment, we explored the possibility of a topical aptamer application in a cream formulation. For that purpose, an ex vivo skin penetration assay was established, in which the penetration of AJ102.29 into the epidermis and dermis was proven. Moreover, topical application of AJ102.29m during CHS supressed ear swelling and reduced T cell migration in CHS, providing proof-of-principle that topical application of an aptamer represents a possibility for development of a non-invasive local ACD treatment. As a further approach towards the development of an ACD therapeutic, aptamer selections specific for human CCL17 were performed but did not lead to a functionally inhibiting aptamer, yet.
Publications
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The GM-CSF/CCL17 pathway in obesity-associated osteoarthritic pain and disease in mice. Osteoarthritis and Cartilage, 31(10), 1327-1341.
Shin, Heonsu; Prasad, Varun; Lupancu, Tanya; Malik, Shveta; Achuthan, Adrian; Biondo, Mark; Kingwell, Bronwyn A.; Thiem, Manja; Gottschalk, Marlene; Weighardt, Heike; Förster, Irmgard; de Steiger, Richard; Hamilton, John A. & Lee, Kevin M.-C.
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Role of the CCL17/CCL22-CCR4-axis in the barrier organs skin and gut. Rheinischen Friedrich-Wilhelms-Universität Bonn.
Gottschalk, M.
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Topical application of a CCL22-binding aptamer suppresses contact allergy. Molecular Therapy - Nucleic Acids, 35(3), 102254.
Jonczyk, Anna; Gottschalk, Marlene; Mangan, Matthew S.J.; Majlesain, Yasmin; Thiem, Manja W.; Burbaum, Lea-Corinna; Weighardt, Heike; Latz, Eicke; Mayer, Günter & Förster, Irmgard
