Effect of Leptospira interrogans outer membrane proteins LipL32 on HUVEC.
Leptospira cause disease through a toxin-mediated process by inducing vascular injury, particularly a small-vessel vasculitis. Breakdown of vessel endothelial cell integrity may increase vessel permeability which is correlated with the changes of tight junction and/or apoptosis in vessel endothelial cells. The specific toxin responsible remains unidentified. In this study, we amplified outer membrane protein LipL32 from the genome of Leptospira interrogans serovar Lai, and it was subcloned in pET32a(+) vector to express thioredoxin(Trx)-LipL32 fusion protein in Escherichia coli BL21(DE3). The protein was expressed and purified, and Trx-LipL32 was administered to culture with human umbilical vein endothelial cells (HUVEC) to elucidate the role of leptospiral outer membrane proteins in vessel endothelial cell. The purified recombinant protein was capable to increase the permeability of HUVECs. And the protein was able to decrease the expression of ZO-1 and induce F-actin in HUVECs display thickening and clustering. Moreover, apoptosis of HUVEC was significantly accelerated. But the fusion partner had no effect in these regards. It is possible that LipL32 is involved in the vessel lesions.
Laboratory of Infection and Immunity, West-China Center of Preclinical and Forensic Medicine, Sichuan University, Chengdu, China.
Zhan
Z
Sun
Lang
L
Bao
DaoKun
D
Li
Bi
B
Huang
Bingting
B
Wu
D000199:Actins / Q000378:metabolism; D017209:Apoptosis; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000302:isolation & purification / Q000633:toxicity*; D002199:Capillary Permeability / Q000187:drug effects; D002478:Cells, Cultured; D003001:Cloning, Molecular; D042783:Endothelial Cells / Q000382:microbiology*; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D005822:Genetic Vectors; D006801:Humans; D007921:Leptospira interrogans / Q000472:pathogenicity*; D008074:Lipoproteins / Q000235:genetics / Q000302:isolation & purification / Q000633:toxicity*; D008565:Membrane Proteins / Q000037:antagonists & inhibitors; D010750:Phosphoproteins / Q000037:antagonists & inhibitors; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000633:toxicity; D062826:Zonula Occludens-1 Protein
D000199:Actins; D001425:Bacterial Outer Membrane Proteins; C406589:LipL32 protein, Leptospira; D008074:Lipoproteins; D008565:Membrane Proteins; D010750:Phosphoproteins; D011994:Recombinant Proteins; C569042:TJP1 protein, human; D062826:Zonula Occludens-1 Protein