Increased Immunogenicity of Mast Cell-Associated Antigens

Dimitris Skokos (1) , Hany Goubran Botros (1) , C Demeure (1) , Joelle Morin (2) , Roger Peronnet (1) , Gerd Birkenmeier (3) , Sarah Boudaly (2) , Salah Mecheri (1)

1 Immuno-Allergie
2 UMR_S 561 - Immunologie, génétique et traitement des maladies métaboliques et du diabète
3 Leipzig University / Universität Leipzig

Background: Mouse bone marrow mast cells (BMMC) have been shown to induce lymphocyte activation through the release of membrane vesicles called exosomes stored in intracytoplasmic granules. The aim of this study is to characterize further the immunostimulatory properties of these exosomes in vivo. Methods: Exosomes isolated from BMMC loaded with bovine serum albumin (BSA) were injected into mice in the absence of adjuvants and antigen-specific antibody responses were measured. Results: Exosomes are located in the endocytic pathway since BSA, under its native as well as degraded form, was found to be associated with these compartments. Exosomes were highly efficient in inducing primary and secondary IgG1 and IgG2a antibody responses, suggesting that naturally occurring adjuvants are present in these compartments. Among several routes of immunization tested, intradermal and subcutaneous injections were found to be the most efficient. Conclusion: This new mechanism may account for a potential role of MC in the monitoring of tissue environment for the presence of non-self-antigens and in the development of specific immunity.

Mots clés: Mast Cells; Basophils; Eosinophils; exosomes; immune response

Domaines: Vaccinologie; Allergologie; Immunité adaptative; Immunité innée

Dimitris Skokos, Hany Goubran Botros, C Demeure, Joelle Morin, Roger Peronnet, et al.. Increased Immunogenicity of Mast Cell-Associated Antigens. Allergy and Clinical Immunology International, 2003. ⟨pasteur-03916966⟩