Treponema pallidum Recombinant Antigens for High-Sensitivity Syphilis LFA & CLIA Development
The Sekbio Syphilis Rapid Test Antigens are recombinant Treponema pallidum proteins — TpN15, TpN17, and TpN47 — expressed individually and as fusion constructs for use as detection antigens in syphilis immunoassay development. These antigens detect anti-T. pallidum antibodies (IgG and IgM) in serum or plasma, enabling treponemal syphilis screening across all stages of infection.
Unlike non-treponemal tests (RPR/VDRL), treponemal antigen-based tests remain reactive throughout the patient's lifetime after treatment — providing permanent serological evidence of prior infection. Multi-epitope antigen design using all three TP antigens (TpN15+17+47) maximizes sensitivity across diverse patient populations with variable antibody profiles.
TpN15, TpN17, and TpN47 each carry distinct immunodominant epitopes — patients may respond variably to different TP antigens. Multi-epitope antigen capture ensures sensitivity across diverse seropositive populations.
Recombinant T. pallidum antigens formulated to minimize cross-reactivity with autoimmune conditions (ANA, RF) and related spirochetes (Borrelia, Leptospira) — reducing false positives in complex co-morbid populations.
Detects anti-TP antibodies in primary, secondary, latent, and tertiary syphilis. Unlike RPR, treponemal antigen tests do not revert to negative after treatment — providing reliable lifetime syphilis serostatus.
Validated for fingerstick whole blood in point-of-care LFA format — enabling syphilis screening in antenatal clinics, STI clinics, and community outreach settings without laboratory infrastructure.
Test design meets WHO Sexually Transmitted Infections (STI) diagnostic performance criteria. Suitable for use in WHO recommended screen-and-treat approaches for antenatal syphilis screening.
TpN15, TpN17, and TpN47 antigens available individually or as pre-mixed fusion constructs for OEM LFA and CLIA kit manufacturers. Custom fusion protein constructs available on request.
| Syphilis Stage | Sensitivity | Reference Confirmation |
|---|---|---|
| Primary syphilis | >94% | Clinical diagnosis + RPR/TPHA |
| Secondary syphilis | >99% | Clinical + RPR/TPHA confirmed |
| Latent syphilis | >99% | TPHA/TPPA confirmed |
| Overall (all stages) | >99.5% | TPPA as reference standard |
| Reference method: TPPA (T. pallidum Particle Agglutination). Full dataset available on request. | ||
| Condition | Result |
|---|---|
| Healthy blood donors (RPR non-reactive) | Non-reactive ✓ |
| Rheumatoid factor positive | Non-reactive ✓ |
| HIV positive (no syphilis history) | Non-reactive ✓ |
| Leptospirosis | Non-reactive ✓ |
| Overall specificity | >99% ✓ |
WHO recommends universal syphilis testing at first antenatal visit. Rapid test format enables same-visit screen-and-treat in low-resource settings — preventing congenital syphilis.
15-minute point-of-care syphilis screening in STI and sexual health clinics. Whole blood fingerstick sample avoids venipuncture and laboratory delays for immediate clinical decision-making.
Multi-epitope recombinant antigens for CLIA automated analyzer integration and ELISA kit development — covering high-throughput hospital laboratory and blood bank syphilis screening applications.
TpN15, TpN17, TpN47 antigens as OEM raw materials for rapid test manufacturers. Custom multi-epitope fusion constructs available. Full analytical and clinical validation dataset for regulatory submissions.
Technical datasheets, performance data, and OEM supply details available on request.