Influences of Leptospira interrogans infection on the expression of intercellular adhesion molecule 1 and vascular cell adhesion molecule 1

Abstract

Objective To investigate the influences of Leptospira interrogans (L.interrogans) infection on the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) on endothelial cells. Methods Expression of ICAM-1 and VCAM-1 at mRNA level was detected by reverse transcription-polymerase chain reaction (RT-PCR) after infecting human umbilical vein endothelial cells (HUVEC) with L. interrogans strain Lai. Silver staining was used to detect leptospires in lung, liver and kidney tissues of L. interrogans-infected C3H/HeJ mice. Expression of ICAM-1 and VCAM-1 in lung, liver and kidney tissues of L. interrogans-infected mice was measured with immunohistochemistry. Results L. interrogans infection increased the expression of ICAM-1 and VCAM-1 on HUVEC (P<0.05). Moreover, the expression of VCAM-1 at mRNA level was significantly higher than that of ICAM-1 (P<0.05). Silver-stained leptospires could be found in lung, liver and kidney tissues of L. interrogans-infected C3H/HeJ mice. Results of the immunohistochemical examination showed that increased expression of both ICAM-1 and VCAM-1 could be detected in ling, liver and kidney tissues of L. interrogans-infected mice, and the VCAM-1 level was significantly higher than that of ICAM-1 in every tissue sample (P<0.05). Conclusion L. interrogans infection could induce the expression of ICAM-1 and VCAM-1 on endothelial cells and increase the expression of VCAM-1 to a level significantly higher than that of ICAM-1, which mediated the infiltration of specific inflammatory cells to the site of infection. Key words: Leptospira interrogans; Adhesion molecule; ICAM-1; VCAM-1