X.P. Wan, X. Yang, G. Lang, W.K. Sun, Y.H. Chen, J.L. Li, Y.R. Gu, R. Liu, Z.Z. Wang, X.B. Lu, R. Gao
Sichuan University, China
pp. 45 - 48
Keywords: chitosan and its derivatives, nanoparticle package and delivery, gene expression, pig interleukin-7, immune response
For sake of developing safe and effective technique to deliver and express animal immune gene in vivo to enhance comprehensive immunity of animal against infectious disease, the interleukin-7 gene of Tibetan pig was firstly cloned and reconstructed into eukaryotic expression plasmid,VR1020. The recombinant plasmid, VRTPIL-7, was expressed in vitro to confirm its bioactivity on lymphocytes of pig and mouse. Then VRTPIL-7 was respectively packed by polyethylenimine (PEI), chitosan(CS),PEG and PEI modified CS(PEG-PEI-CS) and PEG-modified galactosylated chitosan (PEG-GAL-CS). Their nanoparticle sizes, dispersivity and zeta potentials were analyzed.Nanoparticles of VRTPIL-7 were utilized to inject 21-day mice with 100μg recombinant plasmid per mice for studying effect on immunity in vivo. The results were found that,compared with the control, the immune cells and immunoglobulin content significantly increased in the blood of treated mice; the CD4+, CD8+ T cells and mRNA level of TLR1, TLR4 TLR6, TLR9, IL-1,IL-4,IL-6,IL-23 and TGF-β significantly elevated in the treated. These results also indicated that the VTPIL-7 wrapped with CS derivatives induced better innate and adaptive immunity than chitosan, and improved the immunoprotection and disease-resistance of mice, which implying CS derivatives could be promising practicable package molecules to deliver and express immune gene for control of animal diseases.