RT Journal Article SR Electronic(1) A1 Chen, Hong-Ying A1 Zhang, Hong-Ying A1 Li, Xin-Sheng A1 Cui, Bao-An A1 Wang, Shu-Juan A1 Geng, Jing-Wei A1 Li, KunYR 2011 T1 Interleukin-18-mediated enhancement of the protective effect of an infectious laryngotracheitis virus glycoprotein B plasmid DNA vaccine in chickens JF Journal of Medical Microbiology, VO 60 IS 1 SP 110 OP 116 DO https://doi.org/10.1099/jmm.0.024109-0 PB Microbiology Society, SN 1473-5644, AB The immunogenicity of an infectious laryngotracheitis virus (ILTV) glycoprotein B (gB) plasmid DNA vaccine and the immunoregulatory activity of chicken interleukin-18 (IL-18) were investigated in a challenge model. Two recombinant plasmids, pcDNA3.1/gB (pgB) and pcDNA3.1/IL-18 (pIL-18), containing gB and IL-18 were constructed. Chickens were intramuscularly administered two immunizations 2 weeks apart, and challenged with the virulent CG strain of ILTV 2 weeks later. All animals vaccinated with pgB alone or with a combination of pgB plus pIL-18 developed a specific anti-ILTV ELISA antibody and splenocyte proliferation response. The ratios of CD4+ to CD8+ T lymphocytes in chickens immunized with pgB plus pIL-18 were significantly higher than in those immunized with pgB alone. Co-injection of pIL-18 significantly increased the production of gamma interferon and IL-2, indicating that IL-18 enhances the T helper 1-dominant immune response. Challenge experiments showed that the morbidity rate in the pgB group (25 %) was significantly higher than that in the pgB plus pIL-18 group (10 %). The mortality rates in the pgB and pgB plus pIL-18 groups were 10 and 0 %, respectively, and the corresponding protection rates were 60 and 80 %. These results indicate that IL-18 may be an effective adjuvant for an ILTV vaccine., UL https://www.microbiologyresearch.org/content/journal/jmm/10.1099/jmm.0.024109-0