Susceptibility of Treponema pallidum to host-derived antimicrobial peptides.
Cox. David L DL; Sun. Yongcheng Y; Liu. Hsi H; Lehrer. Robert I RI; Shafer. William M WM
Key Findings
- Full‑length LL‑37 and rabbit CAP‑18 kill Treponema pallidum rapidly in lab tests.
- The killing effect is reduced when salt concentrations are high, which may limit systemic use.
- A truncated version of LL‑37 (WS22‑N‑amide) retains activity and prevented infection in a rabbit model.
Practical Outcomes
- For biohackers, the study suggests that short, synthetic fragments of LL‑37 could be explored as topical or localized anti‑syphilis agents, but they are not yet ready for oral or systemic self‑administration. The salt‑sensitivity means formulations would need to control ionic conditions. Further work is needed before any DIY protocol can be safely recommended.
Summary
The human antimicrobial peptide LL‑37 (and a rabbit version) can quickly kill the bacteria that cause syphilis, but its power drops in salty environments. A shorter piece of the peptide, called WS22‑N‑amide, still works and stopped infection in rabbits.
Abstract
LL-37 displays potent broad-spectrum activity against a number of pathogenic bacteria and is the only cathelicidin thus far identified in humans. In this study, we examined the capacity of human LL-37 and the similar CAP-18-derived peptide from rabbits to exert antimicrobial activity against the causative agent of syphilis, Treponema pallidum. We found that both peptides, as well as a truncated version of human LL-37 that contains its bactericidal domain, could exert rapid, but salt-sensitive antimicrobial activity against T. pallidum. Infectivity of T. pallidum in a rabbit model could effectively be blocked with the synthetic truncated LL-37-derived peptide WS22-N-amide.
Study Information
pubmed
2003
2003-11-01T00:00:00.000Z
10.1016/j.peptides.2003.07.026
31
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