Two Potential Syphilis Vaccine Candidates Inhibit Dissemination of Treponema pallidum

Abstract

Syphilis, caused by the spirochete Treponema pallidum subspecies pallidum, continues to be a major public health problem worldwide. Recent increases in the number of syphilis cases, in addition to the lack of an efficient vaccine against T. pallidum for humans, highlights an urgent need for the design and development of an efficacious syphilis vaccine. Here, we assess the vaccine potential of the adhesion protein Tp0136 and the outer membrane protein Tp0663. Rabbits were subcutaneously immunized with recombinant proteins Tp0136, Tp0663, or control PBS. Immunization with Tp0136 or Tp0663 generated a strong humoral immune response with high titers of IgG, as assessed by ELISA. Moreover, animals immunized with Tp0136 or Tp0663 exhibited attenuated lesion development, increased cellular infiltration at the lesion sites, and inhibition of treponemal dissemination to distant organs compared to the unimmunized animals. These findings indicate that Tp0136 and Tp0663 are promising syphilis vaccine candidates. Furthermore, these results provide novel and important information for not only understanding the pathogenic mechanisms of spirochetes, but also the development of spirochete-specific subunit vaccines.

A Review on the Diagnosis and Treatment of Syphilis

“…Tp0136 and Tp0663 immunization proteins can prevent pathogen dissemination in the local areas and also to the distant organ sites at early stages. Tp0136 represented a strong reaction to the serum antibodies with the infected rabbit, while Tp0663 requires further studies [29].…”

Vaccines against sexually transmitted infections: an update

“…Introduction of lymph nodes from Tp0751‐immunized, T. pallidum , ‐challenged animals to naïve animals failed to induce infection, satisfactorily confirming sterile protection. Therefore, Tp0751 is a promising syphilis vaccine candidate, 31 along with other proteins such as Tp0136 (adhesion protein) and Tp0663 (outer membrane protein) 32 …”

“…Therefore, Tp0751 is a promising syphilis vaccine candidate, 31 along with other proteins such as Tp0136 (adhesion protein) and Tp0663 (outer membrane protein). 32…”

Serum Interleukin-26 is a Potential Biomarker for the Differential Diagnosis of Neurosyphilis and Syphilis at Other Stages

“…Syphilis is still a major public health problem, with estimated 36 million occurrences and 12 million new cases worldwide. 2 , 3 Acquired syphilis is divided into primary, secondary, tertiary, latent, and seroresistant syphilis based on disease progression and clinical characteristics. 4–6 Although neurosyphilis is a tertiary syphilis, it is one of the most destructive, concealed, changeable and difficult clinical types of syphilis due to its occurrence at any stage of the infection and its involvement in the CNS with irreversible neurological dysfunction and potentially serious sequelae.…”