Table 2.

Viral complement evasion proteins, their homologues and evasion mechanisms.

Virus Name	Viral Protein	Host Homologue	Targets	Evasion Mechanism
Herpesvirus Saimiri	Complement Control Protein Homologue (CCPH)	DAF, MCP	CP/LP; AP C3 convertase	Decay AccelerationCofactor Activity
Herpesvirus Saimiri	HVSCD59	CD59	C5b-8 and C5b-9	MAC Complex Inhibition
Kaposi’s Sarcoma-Associated Herpesvirus	KSHV Complement Control Protein (KCP)	DAF, MCP	CP/LP and AP C3 convertase	Decay AccelerationCofactor Activity
Murine Gamma-herpesvirus 68	γ-hv68 RCA Protein	DAF, MCP	CP/LP and AP C3 convertase	Exact mechanism unknown; Effect possibly mediated through C3 interaction
Variola Virus	Variola Virus Inhibitor Of Complement Enzymes (SPICE)	MCP	CP/LP and AP C3/C5 convertase	Decay AccelerationCofactor Activity
Vaccinia Virus	Vaccinia Virus Complement Control Protein (VCP)	MCP	CP/LP and AP C3/C5 convertase	Decay AccelerationCofactor Activity
Monkeypox Virus	Monkeypox Virus Inhibitor Of Complement Enzymes (MOPICE)	MCP	CP/LP C3 convertase	Cofactor Activity
Astrovirus	Coat Protein	Human Neutrophil Defensin-1	C1q and MBL	Classical Pathway Inactivation: Disassociates C1s from C1q Lectin Pathway Inactivation: Blocks Masp-2 interaction with MBL
Herpes Simplex Virus	Envelope Surface Glycoprotein C	N/A	AP C3 convertase and C3b	Blocks C3b interaction with properdin and C5 Accelerates decay of alternative pathway C3 Convertase
Hepatitis B virus	HBx protein	N/A	CD46, CD59 and C4BP α	MAC Complex Inhibition CP/LP C3 convertase
Influenza virus	Matrix Protein 1	N/A	C1q	Classical Pathway Inactivation: Inhibits C1q interaction with IgG antibodies
Dengue (DENV), West Nile Virus, And Yellow Fever (YFV)	Non-Structural Protein 1 (NS1)	N/A	C1s, C4, C9	Bind Factor H/C4BP → Cofactor Activity Decreases deposition of C3b and MAC Interacts with C4 And C1s → Reduces classical C3 convertase and reduced deposition of C4b And C3b Binds Clusterin & Vitronectin → MAC Complex Inhibition