Table 3.
Bioactive Element | Sources | Effects | Ref |
---|---|---|---|
Viral Agents | |||
Cytokine response modifier A protein (CrmA) | Cowpox virus (CPV) | Inhibits the production of caspase-1. Prevents formation of mature IL-1β from pro-IL-1β. |
[22, 24] |
vIL-10 | Epstein Barr virus (EBV) Human cytomegalovirus (HCMV) Orf virus (OV) |
Produces homologue to pro-wound healing and anti-inflammatory IL-10. | [22, 26, 28] |
vVEGF | OV | Binds to VEGFR2. Induces pro-wound healing and pro-inflammatory effects of VEGF. | [22, 29] |
vTNFR | CPV HCMV |
Secreted to bind to TNF class of cytokines. Inhibits effect of TNF. |
[22, 131] |
vIL-18BP | EBV OV Molluscum contagiosum virus (MCV) |
Binds to IL-18. Inhibits IL-18-dependent IFN-γ production. | [22, 132] |
vGM-CSFBP | EBV | Binds to granulocyte macrophage colony stimulating factor. Modulates colony formation of macrophages. | [22, 133] |
vMIP2 | Kaposi’s sarcoma- associated virus (KSHV) | Binds MIP2. Inhibits chemokine effect for immune evasion. | [22, 134] |
vCKBP2 | Vaccinia virus | Interacts with receptor binding domain of monocyte chemoattractant protein-1 (MCP-1). Blocks chemokine-receptor interactions. | [22, 135] |
MT-7 | Human myxoma virus (HMV) | Binds to chemokine binding motifs on GAGs in extracellular matrix. Disables the chemokine from binding. No chemokine gradient may be formed and maintained. | [16, 22, 108, 136] |
Bacterial Agents | |||
Cytokine-specific proteases | Porphyromonas gingivalis | Arg-specific HRGP and RGP2 and Lys- specific KGP proteases degrade TNF-α, eliminating one of major mediators of inflammation. | [59] |
Protein A | Staphylococcus aureus | Protein A binds to the Fc region of IgG antibodies. Once bound, the IgG molecules are in the incorrect conformation for recognition from neutrophils or macrophages | [116] |
Extracellular fibrinogen-binding protein (Efb) | Staphylococcus aureus | Efb, is a virulence factor that is able to bind to complement components, C3b. Is able to inhibit complementary opsonization. | [117, 118] |
Clumping factor A (ClfA) | Staphylococcus aureus | ClfA is the main fibrinogen-binding protein found in S. aureus during the stationary phase of growth. Through surface deposition of fibrinogen, the material becomes anti-opsonic. | [119] |