NexaVant™

TLR3 agonist - NexaVant™ (NVT)

NexaVant™ is a double-stranded (ds) RNA-based TLR3 agonist and promising vaccine adjuvant. NexaVant™ (NVT) is a synthetic dsRNA of 424 base pairs produced by performing PCR-coupled bidirectional in vitro transcription of a viral nucleotide segment using T7 RNA polymerase technology.

NexaVant™ displays high purity (≥ 95%) and molecular homogeneity, therefore overcoming various obstacles of currently available dsRNA-based adjuvant candidates, including Poly(I:C) [1]. It induces NF-κB and IRF responses in HEK-Dual™ hTLR3 cells stronger than Poly(A:U), although it is less potent than Poly(I:C) HMW (see figures). Moreover, it does not trigger serious toxicity in preclinical studies [1]. Notably, NexaVant™ has shown promise as an adjuvant for T cell vaccines, enhancing Th1 immune responses and promoting lung-resident memory T cells for long-term and broad protection against respiratory pathogens [2].

InvivoGen also offers NexaVant™ VacciGrade™, a high-quality pre-clinical grade suited for in vivo studies. 

Key features

• Potent TLR3 agonist and vaccine adjuvant
• Highly pure (≥ 95%) and stable
• Ready-to-use liquid
• Batch-to-batch consistency
• Each lot is functionally tested
• High-quality pre-clinical NexaVant™ VacciGrade™ is also available

NexaVant™ is a trademark that belongs to the NA Vaccine Institute. 
NexaVant™ is for research purposes only; not for human or veterinary use.

References:

1. Ko KH, et al., 2023. A novel defined TLR3 agonist as an effective vaccine adjuvant. Front Immunol. ;14:1075291.
2. Ko KH, et al. 2024. A vaccine platform targeting lung-resident memory CD4+ T-cells provides protection against heterosubtypic influenza infections in mice and ferrets. Nat Commun.15(1):10368.

Figures

Molecular weight of NexaVant™ compared to Poly(I:C) HMW.  Poly(I:C) high molecular weight (HMW) (10 µg) and NexaVant™ (100 ng) were visualized on 1% agarose gel. NexaVant™ appears as a single dsRNA band with a length of 424 bp (approximately 275 kDa), while Poly(I:C) migrated as a smear with an average size between 1 kb to 8 kb.

Comparison of TLR3 ligands (NF-κB and IRF responses). HEK-Dual™ hTLR3 cells were stimulated with 10 μg/ml (red) or 1 μg/ml (violet) of Poly(A:U), Poly(I:C) HMW, and  NexaVant™. After overnight incubation, the TLR3-induced (A) NF-κB and (B) IRF  responses were assessed by measuring SEAP and Lucia activity in the supernatant, respectively. Data are shown as optical density (OD) at 630 nm or in fold response over non-induced cells (mean + SEM).

NF-κB and IRF dose-responses of HEK-Dual™ hTLR3 cells to NexaVant™ and Poly(I:C) HMW. HEK-Dual™ hTLR3 cells were incubated with increasing concentrations of NexaVant™ and Poly(I:C) HMW. After overnight incubation, the TLR3-induced (A) NF-κB and (B) IRF responses were assessed by measuring SEAP and Lucia activity in the supernatant, respectively. Data are shown as optical density (OD) at 650 nm or in fold response over non-induced cells (mean + SEM).

Specifications

Description: TLR3 agonist

CAS Number: 2839526-76-8

Quantity: 100 µl

Concentration: 1 mg/ml

Buffer composition: 10mM Phosphate Buffer pH 7.2

Working concentration: 0.1 - 1000 µg/ml

A260/A280 ratio: 1.8 ~ 2.2

Size: 424 bp

Quality control:

• Purity: ≥95% 
• Each lot is functionally tested using cellular assays.
• The absence of bacterial contamination (lipoproteins and endotoxins) has been confirmed using HEK-Blue-Lucia™ hTLR2 and HEK-Blue-Lucia™ mTLR4 cells.

Contents

NexaVant™ is provided as a colorless transparent liquid and is available in two quantities:

• tlrl-nvt: 100 µg at 1 mg/ml
• tlrl-nvt-5: 5 x 100 µg at 1 mg/ml

​ NexaVant™ is shipped at room temperature (RT).

Upon receipt, store at 4°C. NexaVant™ is stable at RT. However, to avoid contamination, we recommend to keep aliquots at 4°C for short-term storage or -20°C for long-term storage.

 The product is stable for up to 1 year when properly stored.

 Avoid repeated freeze-thaw cycles.