Dengue NS1 ST2
Description
Dengue NS1 Protein: Structure and Diagnostic Utility
Dengue NS1 is a non-structural glycoprotein secreted during acute dengue virus (DENV) infection. Key characteristics include:
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Structure: Hexameric form in its soluble state, critical for immune evasion and pathogenesis .
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Function: Facilitates viral replication, modulates host immune responses, and disrupts endothelial integrity .
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Diagnostic Use: Detectable in serum during the first 7 days of illness, with sensitivity comparable to RT-PCR .
Table 1: NS1 Detection Performance in Dengue Diagnosis
| Assay Type | Sensitivity (%) | Specificity (%) | Detection Window | Source |
|---|---|---|---|---|
| NS1 Antigen STRIP | 68–87.5 | 98–100 | Days 1–7 | |
| Lab-based ELISA | 100 | 97 | Days 1–14 |
sST2: A Biomarker for Severe Dengue
Soluble ST2 (sST2) is a member of the IL-1 receptor/TLR superfamily, linked to immune dysregulation and vascular leakage in severe dengue .
Key Findings:
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Kinetics:
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Cardiac Impairment:
Table 2: sST2 Levels Across Dengue Severity Groups
| Severity Group | sST2 (ng/ml) Febrile Phase | sST2 (ng/ml) Critical Phase |
|---|---|---|
| Dengue Fever (DF) | 12.4 ± 3.2 | 8.1 ± 2.5 |
| Severe Dengue (SD) | 25.6 ± 7.8 | 32.9 ± 9.4 |
| Controls | 3.1 ± 1.0 | — |
| Data derived from . |
Pathophysiological Link Between NS1 and sST2
While NS1 and sST2 are not a single compound, their roles intersect in dengue pathogenesis:
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NS1 triggers endothelial dysfunction and cytokine storms, indirectly elevating sST2 .
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sST2 amplifies vascular leakage via IL-33/ST2L signaling, exacerbating severe outcomes .
Therapeutic Implications:
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Heparan sulfate mimetics (e.g., PG545) inhibit both NS1-mediated vascular leakage and viral entry .
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sST2 modulation may improve outcomes in severe dengue, though optimal timing remains under investigation .
Research Gaps and Future Directions
Product Specs
Product Science Overview
Dengue virus (DENV) is a mosquito-borne virus that belongs to the Flaviviridae family. It is responsible for causing dengue fever, a disease that affects millions of people worldwide, particularly in tropical and subtropical regions. The virus is transmitted primarily by Aedes aegypti and Aedes albopictus mosquitoes. There are four distinct serotypes of the dengue virus, namely DENV-1, DENV-2, DENV-3, and DENV-4. Infection with one serotype provides lifelong immunity to that specific serotype but not to the others, which means a person can be infected with dengue up to four times.
Non-structural protein 1 (NS1) is a glycoprotein encoded by the dengue virus genome. It is a multifunctional protein that plays a crucial role in the viral replication cycle and pathogenesis. NS1 is involved in the formation of the viral replication complex and is essential for viral RNA synthesis. Additionally, NS1 is secreted from infected cells and can be found in the bloodstream of infected individuals. It is known to interact with various components of the host immune system, contributing to immune evasion and pathogenesis.
NS1 subtype 2 refers to the NS1 protein derived from the DENV-2 serotype. DENV-2 is one of the most prevalent and virulent serotypes of the dengue virus. The NS1 protein of DENV-2 has been extensively studied due to its significant role in the disease’s severity and its potential as a diagnostic marker and vaccine target.
Recombinant NS1 refers to the NS1 protein that has been produced using recombinant DNA technology. This involves inserting the gene encoding the NS1 protein into an expression system, such as bacteria, yeast, or mammalian cells, to produce the protein in large quantities. Recombinant NS1 is used in various research and diagnostic applications, including the development of diagnostic assays and vaccines.
- Diagnostic Marker: Recombinant NS1 is used in diagnostic assays to detect dengue virus infection. NS1 antigen detection tests are widely used for early diagnosis of dengue, as NS1 can be detected in the blood of infected individuals during the acute phase of the disease.
- Vaccine Development: NS1 is considered a potential target for dengue vaccines. Studies have shown that immunization with recombinant NS1 can induce protective immunity against dengue virus infection. NS1-based vaccines are being explored as a strategy to prevent dengue.
- Pathogenesis Studies: Recombinant NS1 is used in research to study the mechanisms of dengue virus pathogenesis. By understanding how NS1 interacts with the host immune system and contributes to disease severity, researchers can develop targeted therapies to mitigate the effects of dengue.
