CD69 modulates sphingosine-1-phosphate-induced migration of skin dendritic cells
Amalia Lamana1, Pilar Martin, Hortensia de la Fuente
1Servicio de Inmunología, Hospital de la Princesa, Universidad Autónoma de Madrid, Madrid, Spain.
Insights
CD69 deficiency enhances dendritic cell (DC) migration from skin to lymph nodes by modulating sphingosine-1-phosphate receptor 1 (S1P(1)) function. This finding offers insights into DC trafficking for targeted therapies.
Area of Science:
- Immunology
- Cell Biology
Background:
- CD69 is an early inducible leukocyte activation receptor.
- Dendritic cells (DCs) play a crucial role in immune responses by migrating from peripheral tissues to lymph nodes.
- Understanding DC migration is key for developing effective immunotherapies.
Purpose of the Study:
- To investigate the role of CD69 in murine dendritic cell differentiation, maturation, and migration.
- To elucidate the mechanisms by which CD69 influences DC trafficking, particularly in the context of skin sensitization.
- To explore the potential of targeting CD69 for modulating DC migration in vivo.
Main Methods:
- Contact sensitization model in mice.
- Subcutaneous transfer of CD69 knockout (CD69-/-) DCs.
- Two-photon microscopy for analyzing DC motility.
- Chemotaxis assays to sphingosine-1-phosphate (S1P).
- Flow cytometry to assess S1P receptor expression (S1P(1) and S1P(3)).
- In vivo treatment with S1P analogs (SEW2871 and FTY720).
Main Results:
- Skin DCs express CD69 upon maturation stimuli.
- CD69-/- DCs exhibited enhanced migration from skin to draining lymph nodes.
- CD69 deficiency did not affect interstitial motility of DCs within lymph nodes.
- CD69-/- DCs showed enhanced chemotaxis to S1P and increased S1P(1) expression.
- In vivo S1P analog treatment reduced skin DC migration.
Conclusions:
- CD69 negatively regulates S1P-induced migration of skin DCs to lymph nodes.
- CD69 modulates S1P(1) function, thereby controlling DC trafficking.
- These findings enhance understanding of DC migration patterns and suggest therapeutic strategies for antigen delivery.
Abstract:
In this study, we have investigated the role of CD69, an early inducible leukocyte activation receptor, in murine dendritic cell (DC) differentiation, maturation, and migration. Skin DCs and DC subsets present in mouse lymphoid organs express CD69 in response to maturation stimuli. Using a contact sensitization model, we show that skin DCs migrated more efficiently to draining lymph nodes (LNs) in the absence of CD69. This was confirmed by subcutaneous transfer of CD69-/- DCs, which presented an increased migration to peripheral LNs. Two-photon microscopy analysis showed that once DCs reached the LNs, CD69 deficiency did not alter DC interstitial motility in the LNs. Chemotaxis to sphingosine-1-phosphate (S1P) was enhanced in CD69-/- DCs compared with wild-type DCs. Accordingly, we detected a higher expression of S1P receptor type-1 (S1P(1)) by CD69-/- DCs, whereas S1P(3) expression levels were similar in wild-type and CD69-/- DCs. Moreover, in vivo treatment with S1P analogs SEW2871 and FTY720 during skin sensitization reduced skin DC migration to peripheral LNs. These results suggest that CD69 regulates S1P-induced skin DC migration by modulating S1P(1) function. Together, our findings increase our knowledge on DC trafficking patterns in the skin, enabling the development of new directed therapies using DCs for antigen (Ag) delivery.
