Figure 3.

Viral subversion of Siglec-1-mediated extracellular vesicle dissemination. DCs capture extracellular vesicles bearing MHC–peptide complexes or distinct enveloped viruses such as HIV-1 or EBOV through Siglec-1 recognition of sialylated gangliosides and are then trafficked and stored within a sac-like compartment. While captured extracellular vesicles exit this compartment to present antigens to T cells via immune synapse formation complemented by the co-stimulatory signals provided by the activated DC, the exit of HIV-1 leads to the trans-infection of CD4⁺ T cells. In the case of EBOV, viral dissemination to other target cells needs further investigation. MHC-II: major histocompatibility complex class II; TCR: T cell receptor.