Sindbis Virus (SINV) Research Reagents — Antibodies & Recombinant Proteins

Spike Glycoprotein E2 — Receptor Binding & Neutralization Target
E2 mediates attachment to host cell receptors and is the primary target for virus-neutralizing antibodies. E2 forms a heterodimer with E1 and assembles into trimeric spikes (80 spikes per virion) in a T=4 icosahedral lattice — one of the best-characterized viral surface architectures. Available:
• Recombinant E2 proteins: N-His (VK002062) and C-Fc (VK002061)
• Anti-E2 recombinant antibody SAA2271 (VK002063)
• Anti-E2 polyclonal antibody (VK002064)

Spike Glycoprotein E1 — Class II Fusion Protein
E1 is the class II fusion glycoprotein that mediates low-pH-triggered membrane fusion in endosomes. E1 is shielded by E2 in the prefusion state and undergoes a dramatic conformational rearrangement to form E1 homotrimers during fusion. Available:
• Recombinant E1 proteins in three formats: N-His (VK720012), C-His (VK002041), and C-Fc (VK002052)
• Anti-E1 polyclonal antibody (VK720014)

nsP2 — Protease / Helicase / RNA Capping Enzyme
nsP2 is a multifunctional enzyme: the N-terminal domain has RNA helicase and triphosphatase (RNA capping) activity, while the C-terminal domain is the cysteine protease responsible for polyprotein processing. nsP2 is also the primary determinant of SINV-induced host shutoff (inhibition of host transcription) — a critical factor in oncolytic vector design. Available: recombinant nsP2 protein C-His (VK002012) and anti-nsP2 polyclonal antibody (VK002014).

nsP3 — Macro Domain / Phosphoprotein
nsP3 contains the conserved alphavirus macro domain (ADP-ribose-1″-phosphatase) and a hypervariable C-terminal domain that recruits host G3BP1/2 to disassemble stress granules — a key immune evasion mechanism shared across alphaviruses. Available: recombinant nsP3 protein N-His (VK002022) and anti-nsP3 polyclonal antibody (VK002024).

nsP4 — RNA-Dependent RNA Polymerase (RdRp)
nsP4 is the catalytic core of the alphavirus replication complex. nsP4 is the target for polymerase-targeting antivirals and is the most conserved alphavirus protein — reagents against SINV nsP4 may cross-react with related alphaviruses (CHIKV, GETV, VEEV). Available: recombinant nsP4 protein N-His (VK002032) and anti-nsP4 polyclonal antibody (VK002034).

Do SINV reagents cross-react with CHIKV or other alphaviruses?
Structural proteins (E1/E2) are relatively divergent between alphavirus species — cross-reactivity is limited. However, nsP4 (RdRp) is the most conserved alphavirus protein, and our anti-nsP4 pAb (VK002034) may show cross-reactivity with CHIKV, GETV, and other Old World alphaviruses. Contact us for cross-reactivity testing data.

Which reagents are most relevant for SINV-based vector and oncolytic virus research?
For monitoring vector replication and transgene expression: anti-nsP2 pAb (VK002014) detects non-structural protein expression (replication marker), and anti-E2 pAb (VK002064) or anti-E2 recombinant antibody SAA2271 (VK002063) detect structural protein expression and virion assembly. For host shutoff studies: nsP2 protein and antibody are essential tools.

What is the difference between E1 and E2 for neutralization assays?
E2 is the primary neutralization target — anti-E2 antibodies block receptor binding and are the most potent neutralizers. E1 is shielded by E2 and only accessible in the post-fusion conformation. For neutralization studies, we recommend the anti-E2 recombinant antibody SAA2271 (VK002063) as a positive control.

Explore reagents for related alphaviruses and arboviruses:

SINV ✓ CHIKV GETV Dengue (DENV) West Nile (WNV) Zika (ZIKV) YFV