BMC Veterinary Research (Oct 2012)

Effects of over-expression of TLR2 in transgenic goats on pathogen clearance and role of up-regulation of lysozyme secretion and infiltration of inflammatory cells

  • Deng Shoulong,
  • Yu Kun,
  • Zhang Baolu,
  • Yao Yuchang,
  • Liu Yufeng,
  • He Haijuan,
  • Zhang Hongtao,
  • Cui Maosheng,
  • Fu Juncai,
  • Lian Zhengxing,
  • Li Ning

DOI
https://doi.org/10.1186/1746-6148-8-196
Journal volume & issue
Vol. 8, no. 1
p. 196

Abstract

Read online

Abstract Background Toll-like receptor 2 (TLR2) is important to host recognition of invading gram-positive microbes. In goats, these microbes can cause serious mastitis, anthrax, tetanus, and other problems. Transgenic goats constitutively over-expressing TLR2 in many tissues serve as a suitable model for the study of the role of TLR2 over-expression in bacterial clearance. Results Capra hircus TLR2 over-expression vector (p3S-LoxP-TLR2) was used to generate transgenic goats by egg microinjection. The integration efficiency was 8.57%. Real-time PCR and immunohistochemical results confirmed that the goats over-expressing the TLR2 gene (Tg) expressed more TLR2 than wild-type goats (WT). Monocyte-macrophages from the bloodstreams of transgenic goats were stimulated with synthetic bacterial lipoprotein (Pam3CSK4) and by the promotion of interleukin-6 (IL-6) and IL-10 expression in vitro. The oxidative damage was significantly reduced, and lysozyme (LZM) secretion was found to be up-regulated. Ear tissue samples from transgenic goats that had been stimulated with Pam3CSK4 via hypodermic injection showed that transgenic individuals can undergo the inflammation response very quickly. Conclusions Over-expression of TLR2 was found to decrease radical damage to host cells through low-level production of NO and MDA and to promote the clearance of invasive bacteria by up-regulating lysozyme secretion and filtration of inflammatory cells to the infected site.

Keywords