Table 3 Mechanisms of OMV-induced host immune responses
Mechanism Type | Description | Host Cellular Response |
|---|---|---|
Endocytosis | OMVs enter host cells through macropinocytosis, clathrin-mediated endocytosis, and caveolae-mediated endocytosis. | Promotes the production of inflammatory factors such as IL-8. |
Proteins and Lipids | Membrane proteins and lipids carried by OMVs can activate pattern recognition receptors (such as TLRs) on host cells. | Activates inflammatory and immune signaling pathways. |
Immunostimulatory Molecules | Molecules such as lipopolysaccharides (LPS) and PG can strongly activate the host’s immune response. | Induces the expression of inflammatory cytokines and the recruitment of immune cells. |
DNA and RNA | Nucleic acids in OMVs can be recognized by innate immune receptors in host cells, such as NOD-like receptors. | Promotes the production of type I interferons and other inflammatory mediators. |
Bacterial Toxins | Some OMVs may carry bacterial toxins that can directly damage host cells or modulate host immune responses. | Causes cell death, inflammation, and tissue damage. |
Antigen Presentation | OMVs can be captured by antigen-presenting cells such as dendritic cells, thereby activating T cells. | dendritic cells, thereby activating T cells.Activates adaptive immune responses, including cytotoxic T cells and helper T cells. |