Expression of Surface Antigens in HaCaT Cells by Virulent Treponema Pallidum

Lee, Jong Seo; Lee, Min Geol; Lee, Kwang Hoon; Lee, Jung Bock

Abstract

BACKGROUND: In primary syphilis, Treponema pallidum invades skin and mucosa through the epidermis, enters blood vessels and circulates in the blood. Afterwards, T. pallidum migrates out of the blood vessels to the pidermis in secondary syphilis to induce diverse skin findings. Therefore, the epidermis seems to be one of the main targets in syphilis. Most of the epidermal cells are keratinocytes and it can be presumed that T. pallidum infection elicits defence mechanisms at keratinocyte level resulting in changes of the keratinocyte surface molecule expression.
OBJECTIVE
We have examined by ELISA whether virulent T. pallidum and its 47-kDa antigen could change the expressions of E cadherin, MHC-I, and ICAM-1 on the surface of HaCaT, a transformed human kerainocyte cell line.
METHODS
The 96 well plates of 4 x 10(4) HaCaT cells/well were cultured for 1-2 days at 37 degrees C, and cultured for 16 hours at 37 degrees C including 3x 10(5) T. pallidum per well or its 47-kDa antigen. Then the changes of E-cadherin, MHC-I and, ICAM-I were observed by ELISA. Media alone was used for negative control and TNF-alpha of 10U/well was used for positive control.
RESULTS
On culturing with T. pallidum, the expression of E-cadherin and MHC-I increased significantly compared with the negative control. That of ICAM-1 showed increased findings compared to the negative control, but it was not significant. On culturing with its 47-kDa antigen, the expression of E-cadioerin and MHC-I increased significantly compared with negative control ICAM-1 expression was increased compared to the negative control, but it was not significant.
CONCLUSION
The increase in E-cadherin and MHC-I expressions in HaCaT cells cultured with T. pallidum may be related to the defence mechanisms of the host cells.