[Recombinant porcine lung surfactant protein A inhibits porcine reproductive and respiratory syndrome virus infection into host cells in vitro].

Abstract

OBJECTIVE:

To investigate the antiviral activity of porcine lung surfactant protein A (SP-A) to porcine reproductive and respiratory syndrome virus (PRRSV) in vitro.

METHODS:

The SP-A gene was amplified by PCR from the plasmid containing porcine SP-A gene, and subcloned into pcDNA3. 1A-CD5 vector containing the human CD5 signal peptide to generate SP-A eukaryotic expression vector pcDNA-CD5-SPA/MH. The recombinant expression vector was transfected into HEK293T cells mediated with calcium phosphate. The expressed recombinant SP-A was identified by Western blot and purified from culture medium by Ni-NTA-Agarose beads. The binding activity of SP-A with PRRSV was identified by ELISA. The antiviral activity of SP-A to PRRSV was analyzed by viral titer reduction assays on MARC-145 cells and porcine alveolar macrophages (PAM).

RESULTS:

The results showed that the eukaryotic expression vector of SP-A gene could mediate SP-A expression in HEK293T cells, the expressed SP-A could bind PRRSV in a dose dependent manner. The PRRSV incubated in advance with SP-A showed the lower infective activity compared with no-SP-A-incubated PRRSV on both MARC-145 cells and porcine alveolar macrophages. The SP-A-treated PRRSV titers in MARC-145 cells and PAM cells were significantly lower than that of SP-A-untreated PRRSV at 72 h post-infection.

CONCLUSION:

Recombinant porcine SP-A significantly inhibit the infection of PRRSV to the host cells in vitro, which indicates that recombinant SP-A possesses anti-PRRSV activity.

• Authors: Feng Zhang, Fei Zhong, Xiujin Li, Xingxing Wang, Kao Zhang, Huihui Chen, Zhen Li, Wenyan Li, Hongli Pan, Dongmei Han
• Journal: Wei sheng wu xue bao = Acta microbiologica Sinica (Wei Sheng Wu Xue Bao) Vol. 52 Issue 5 Pg. 654-60 (May 04 2012) ISSN: 0001-6209 [Print] China
• PMID: 22803352 (Publication Type: English Abstract, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Pulmonary Surfactant-Associated Protein A
• Recombinant Proteins

Topics

• Animals
• Cell Line
• HEK293 Cells
• Humans
• Macrophages, Alveolar (immunology, virology)
• Porcine Reproductive and Respiratory Syndrome (immunology, prevention & control)
• Porcine respiratory and reproductive syndrome virus (immunology, physiology)
• Pulmonary Surfactant-Associated Protein A (biosynthesis, genetics, immunology)
• Recombinant Proteins (biosynthesis, genetics, immunology)
• Swine
• Virus Replication