Cytokine and receptor expression in skin draining lymph nodes after skin immunization

Topical (epicutaneous, e.c.) application of the adjuvant CpG ODN during immunization leads to a robust immune response compared to when subcutaneous (s.c.) administration. Dendritic cells are hematopoietically derived cells that are important in cross-presenting to and activating CD8 T cells. Dermal dendritic cells are one of the two major dendritic cell subsets found in the skin which mobilize from the skin to draining lymph nodes to present to T cells upon activation. Dermal dendritic cells are found in skin draining lymph nodes around 24 hours post immunization. To determine how the immune system respond differently between e.c. versus s.c. administration of CpG ODN, we evaluated changes in the skin draining lymph node environment upon the two routes of adjuvant application. Expression chemokines and chemokine receptors were assessed with real-time qPCR. To determine the changes in the skin draining lymph node environment (cytokine and cytokine receptor levels) upon immunization via real time RT-PCR. Adult C57bL/6 mice were immunized via subcutaneous injection of chicken ovalbumin (OVA) in the presence or absence of the adjuvant CpG ODN 1826 administered subcutaneously or epicutaneously. Skin draining lymph nodes were harvested for analysis.