Microvesicles are key players in cellular communication. As glandular secretions present a rich source of active exosomes, we hypothesized that exosome-like vesicles are present in Apis mellifera hypopharyngeal gland secretomal products (honey, royal jelly and bee pollen), and participate in their known antibacterial and pro-regenerative effects. We developed an isolation protocol based on serial centrifugation and ultracentrifugation steps and demonstrated the presence of protein-containing exosome-like vesicles in all three bee-derived products. Assessing their antibacterial properties, we found that exosome-like vesicles had bacteriostatic, bactericidal and biofilm-inhibiting effects on Staphylococcus aureus. Furthermore, we demonstrated that mesenchymal stem cells (MSCs) internalize bee-derived exosomelike vesicles and that these vesicles influence the migration potential of the MSCs. In an in vitro wound-healing assay, honey and royal jelly exosome-like vesicles increased migration of human MSCs, demonstrating their inter-kingdom activity. In summary, we have discovered exosome-like vesicles as a new, active compound in bee pollen, honey and royal jelly.
Bibliographical noteFunding Information:
This work was supported by CONICYT FONDECYT (Comisión Nacional de Investigación Cientıf́ ica y Tecnológica – Fondo Nacional de Desarrollo Cientıf́ ico y Tecnológico) grant no. 11180406 and 11180101.
© 2019 Published by The Company of Biologists Ltd | Journal of Experimental Biology.
- Apis mellifera
- Inter-kingdom communication
- Intercellular communication