Expression data of muscle and draining lymph node after intramuscular ISCOM-Matrix vaccine adjuvant treatment

ISCOM vaccines induce a balanced Th1/Th2 response and cytotoxic T lymphocytes. The adjuvant component, ISCOM-Matrix, consists of purified saponin fractions, cholesterol and phospholipids. The mode of action for the ISCOM-Matrix is known to some extent but still we lack knowledge of important segments in initiation of the immune response. The study was performed to analyze the early transcriptional responses to the ISCOM-Matrix alone, without the use of co-administered antigen. Matrix M (AbISCO® 100) was given as intramuscular injection and after 24 hours the pigs was sacrificed for gene expression analysis, performed for the injection site and the draining lymph node. Results revealed 594 and 362 genes to be differentially expressed (FC > 2; q < 0.05) at the injection site and in the lymph node, respectively. This show that the ISCOM-Matrix, without any antigen added, has a clear immunomodulatory effect at the site of administration as well as in the draining lymph node. Six pigs, castrated males, 11 weeks old was used for the experiment. They were sorted two weeks prior the treatment and kept separate throughout the experiment. 3 pigs were intramuscularly (biceps femoris) injected with ISCOM-Matrix (AbISCO® 100) suspended in 1 ml sterile saline. 3 control animals were similarly injected with saline only. The pigs were sacrificed after 24 hours and muscle tissue from injection site and draining (internal iliac) lymph nodes were collected and transferred to RNAlater for RNA isolation.