Inflammation and Immunopharmacology

Lentiviral vector-mediated siRNA knockdown of SR-PSOX inhibits foam cell formation in vitro

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Abstract

Aim:

To investigate the expression of scavenger receptor that binds phosphatidylserine and oxidized lipoprotein (SR-PSOX)/CXC chemokine ligand 16 (CXCL16) in the human monocyte-derived cell line THP-1, and the effect of lentiviral vectors for the stable delivery of SR-PSOX/CXCL16 short hairpin RNA on foam cell formation.

Methods:

A lentiviral expression vector containing enhanced green fluorescence protein (GFP) and SR-PSOX small interfering RNA (siRNA) (Lenti-SR-PSOXsi), or the control siRNA (Lenti-NC) gene was constructed. A human monocyte-derived cell line THP-1 was transfected with a different multiplicity of infection (MOI) of Lenti-SR-PSOXsi or Lenti-NC, and cultured to obtain stably-transfected THP-1KD and THP-1NC cells. After incubation with oxidatively-modified, low-density lipoprotein (Ox-LDL), the expression of SR-PSOX/CXCL16 mRNA was determined by real-time PCR. The expression of the SR-PSOX/CXCL16 protein was detected by flow cytometry analysis. The effect of Lenti-SR-PSOXsi on foam cell formation was assessed by Oil red O-stain analysis.

Results:

Ox-LDL increased the expression of SR-PSOX/CXCL16 mRNA in a time- and dose-dependent manner in THP-1 cells. Four days after transfection with Lenti-SR-PSOXsi (MOI: 100), the percentage of GFP expression cells was over 89.3%. The expression of the SR-PSOX/ CXCL16 mRNA and protein in THP- 1KD cells significantly decreased compared with the parent cells, even the THP-1KD cells stimulated with 40 mg/L Ox-LDL. Ox-LDL uptake experiments in THP-1- and THP-1KD-derived macrophages indicated that SR-PSOX/CXCL16 deficiency decreased the development of macrophage-derived foam cell formation.

Conclusion:

The above data showed that SR-PSOX siRNA delivered by using lentiviral vectors in THP-1 cells was a powerful tool for studying the effect of SR-PSOX, and decreased the expression of the SR-PSOX gene by inhibiting macrophage-derived foam cell formation.

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Author information

Correspondence to Yao-cheng Rui or Li-xin Wei.

Additional information

This project was supported by the National Natural Science Foundation of China (No 30500615), the Young Scholars Foundation of Shanghai Public Health Bureau (No 2004-55-94), and the Young Scholars Foundation of SMMU (No 2005-SQ-11).

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Zhang, L., Liu, H., Li, T. et al. Lentiviral vector-mediated siRNA knockdown of SR-PSOX inhibits foam cell formation in vitro. Acta Pharmacol Sin 29, 847–852 (2008) doi:10.1111/j.1745-7254.2008.00823.x

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Keywords

  • SR-PSOX
  • CXCL16
  • lentiviral vector
  • small interfering RNA
  • atherosclerosis
  • oxidatively-modified
  • low-density lipoprotein

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