comparative effect of different vaccines on immune-related gene expressions of rainbow trout (oncorhynchus mykiss) and experimentally infected with streptococcus iniae and lactococus garvie

To understand how different vaccines, i.e., bivalent formalin-inactivated vaccine (lactococus garvie and streptococcus iniae), could affect the immune-related gene expressions, the tnfalpha, il1 beta; and il8 genes of head kidney was measured in oncorhynchus mykiss. to address this, 630 juvenile fish weighing 26 ±3 g were initially (day 0) injected by three different treatments, including control group (normal saline only), aquavactm garvetil (merck) and iranian vaccine (jehade daneshagahi) and followed by bath immersion into the same vaccine on day 30. the head kidney was withdrawn to measure immune related gene expressions at the beginning of experiment (day 0), and following 14, 30, 45 and 60 days of post-vaccination. in the next step, control and both vaccinated groups were also subjected to either l. garvie or s. iniae challenge. similar samples were taken immediately following bacteria injection (time= 0) and 12, 48, 72 h, and following 7 and 10 days of challenged test. the realtime pcr indicated upregulation of all cytokine genes following vaccination at day 14 as compared to initial day (p<0.05). in prechallenged experiment, the higher induction in the level of those genes in the head kidney was related to aquavac vaccine (p<0.05). injection by s. iniae and l. garviae induced the level of immunerelated gene expression in the head kidney within the first few days with higher intensity in case of unvaccinated control group. although the aquavac produces higher upregulation of inflammatory gene expression rather than iranian vaccine, the immunostimulatory effects of both vaccines is a timerestricted.