Virulent Treponema pallidum Activates Human Vascular Endothelial Cells

Bryan S. Riley, Nancy Oppenheimer-Marks, Eric J. Hansen, Justin D. Radolf, Michael V. Norgard

Research output: Contribution to journalArticlepeer-review

69 Scopus citations


Perivascular lymphocytic infiltration, fibrin deposition, and endothelial cell abnormalities consistent with cellular activation are prominent histopathologic features of syphilis, a sexually transmitted disease caused by the spirochetal bacterium Treponema pallidum. Because activated endothelial cells play important roles in lymphocyte homing and hemostasis, the ability of virulent T. pallidum to activate cultured human umbilical vein endothelial cells (HUVEC) was investigated. T. pallidum induced the expression of intercellular adhesion molecule-1 (ICAM-1) and procoagulant activity on the surface of HUVEC. Electron microscopy of T. pallidum-stimulated HUVEC revealed extensive networks of fibrin strands not observed in cultures without trepo- nemes. ICAM-1 expression in HUVEC also was promoted by a 47-kDa integral membrane lipoprotein purified from T. pallidum, implicating a role for spirochete membrane lipoproteins in endothelial cell activation. The combined findings are consistent with the pathology of syphilis and provide the first evidence that a pathogenic spirochetal bacterium such as T. pallidum or its constituent integral membrane lipoprotein(s) can activate directly host vascular endothelium.

Original languageEnglish (US)
Pages (from-to)484-493
Number of pages10
JournalJournal of Infectious Diseases
Issue number3
StatePublished - Mar 1992

ASJC Scopus subject areas

  • General Medicine


Dive into the research topics of 'Virulent Treponema pallidum Activates Human Vascular Endothelial Cells'. Together they form a unique fingerprint.

Cite this