# Optimization to Improve the Protective Capacity of the Tp0751 Syphilis Vaccine Candidate

> **NIH NIH U19** · UNIVERSITY OF WASHINGTON · 2020 · $444,796

## Abstract

PROJECT SUMMARY/ABSTRACT
The bacterium that causes syphilis, Treponema pallidum subsp. pallidum, disseminates widely throughout an
infected host to infect every organ and tissue. Previous studies conducted in the Cameron laboratory have
identified a surface-exposed T. pallidum adhesin, designated Tp0751, which mediates attachment to
endothelial cells and, as such, plays an important role in the process of T. pallidum dissemination. In initial
studies, immunization of rabbits with this treponemal adhesin induced an immune response that provided
significant protection against T. pallidum dissemination. The long-term objective of the studies contained in this
proposal is to expand on these prior promising protection results and develop an enhanced vaccinogen that
fully protects immunized animals against disseminated T. pallidum infection. To accomplish this objective, the
following specific aims are proposed: (1) determine the protective region(s) of the Tp0751 immunogen; (2)
optimize the Tp0751 vaccinogen formulation; (3) optimize the delivery of the Tp0751 vaccinogen; and (4) test
the heterologous protective capacity and duration of achieved protection of the optimal Tp0751 and Tpr
vaccine formulation and delivery system. We anticipate these investigations will generate a syphilis candidate
vaccine that exhibits protection against disseminated infection and, when combined with the optimized Tpr
vaccinogen from Scientific Project 2, will provide complete protection against syphilis.

## Key facts

- **NIH application ID:** 9982774
- **Project number:** 5U19AI144133-02
- **Recipient organization:** UNIVERSITY OF WASHINGTON
- **Principal Investigator:** CAROLINE E CAMERON
- **Activity code:** U19 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $444,796
- **Award type:** 5
- **Project period:** 2019-08-01 → 2024-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9982774

## Citation

> US National Institutes of Health, RePORTER application 9982774, Optimization to Improve the Protective Capacity of the Tp0751 Syphilis Vaccine Candidate (5U19AI144133-02). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/9982774. Licensed CC0.

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