Assessment of the Kinetics ofTreponema pallidumDissemination into Blood and Tissues in Experimental Syphilis by Real-Time Quantitative PCR
- 1 June 2007
- journal article
- Published by American Society for Microbiology in Infection and Immunity
- Vol. 75 (6), 2954-2958
- https://doi.org/10.1128/iai.00090-07
Abstract
Little is known about the size and kinetics of treponemal burdens in blood and tissues during acquired or experimental syphilitic infection. We used real-time quantitative PCR to measure Treponema pallidum DNA levels in rabbits infected intratesticularly with the prototype Nichols strain. At the outset, we performed a series of in vitro blood spiking experiments to determine the effect of blood processing procedures on the distribution of treponemes in various blood components. T. pallidum DNA levels in plasma and whole blood were approximately 10-fold higher than those in serum and more than 200-fold greater than those in peripheral blood mononuclear cells (PBMCs). Ten rabbits were inoculated intratesticularly with doses of treponemes ranging from 4 x 10(7) to 2 x 10(8) organisms. In five rabbits, T. pallidum DNA levels were measured sequentially in serum, plasma, whole blood, and PBMCs until sacrifice at peak orchitis, at which time brain, kidney, liver, spleen, and testicles were harvested; blood and organs were also harvested at orchitis from the other five rabbits. T. pallidum DNA was detected in plasma within 24 h postinfection. Treponeme levels in whole blood and blood components increased significantly with the development of peak orchitis. Overall, levels in serum and PBMCs were lower than those in plasma and whole blood; this disparity was particularly marked at early time points. Significantly greater numbers of spirochetes were found in the spleen than in liver, kidney, or brain tissue at the time of sacrifice. Our findings highlight the remarkable capacity of T. pallidum to disseminate from the site of infection to blood and tissues, and they identify the spleen as a prime target for treponemal invasion.Keywords
This publication has 39 references indexed in Scilit:
- Detection of Treponema pallidum subsp. pallidum from Skin Lesions, Serum, and Cerebrospinal Fluid in an Infant with Congenital Syphilis after Clindamycin Treatment of the Mother during PregnancyJournal of Clinical Microbiology, 2007
- Development of a Real-Time PCR Assay To Detect Treponema pallidum in Clinical Specimens and Assessment of the Assay's Performance by Comparison with Serological TestingJournal of Clinical Microbiology, 2007
- Quantitative Assessment of Protection in Experimental SyphilisInfection and Immunity, 2005
- Molecular Subtyping of Treponema pallidum from North and South CarolinaJournal of Clinical Microbiology, 2005
- Treponema pallidumStrain‐Specific Differences in Neuroinvasion and Clinical Phenotype in a Rabbit ModelThe Journal of Infectious Diseases, 2005
- Use of PCR in the diagnosis of early syphilis in the United KingdomSexually Transmitted Infections, 2003
- Identification of aTreponema pallidumLaminin-Binding ProteinInfection and Immunity, 2003
- Studies of rabbit testes infected with Treponema pallidum. III. Immunosuppressive activity of infiltrating mononuclear cells.Sexually Transmitted Infections, 1984
- Host Response to Treponema pallidum in Intradermally-Infected Rabbits: Evidence for Persistence of Infection at Local and Distant SitesJournal of Investigative Dermatology, 1980
- Infectivity tests in syphilis.Sexually Transmitted Infections, 1969