Immunomodulatory Effects of an Enzymatic Extract from Ecklonia cava on Murine Splenocytes

We investigated whether the brown seaweed Alariaceae Ecklonia cava (E. cava) has immunological effects on splenocytes in vitro. For that purpose, we prepared an enzymatic extract from E. cava (ECK) by using the protease, Kojizyme. Here, ECK administered to ICR mice dramatically enhanced the proliferation of their splenocytes and increased the number of their lymphocytes, monocytes and granulocytes. In flow cytometry assays performed to identify in detail the specific phenotypes of these proliferating cells after ECK treatment, the numbers of CD4⁺ T cells, CD8⁺ T cells and CD45R/B220⁺ B cells increased significantly compared to those in untreated controls. In addition, the mRNA expression and production level of Th1-type cytokines, i.e., TNF-α and IFN-γ, were down-regulated, whereas those of Th2-type cytokines, i.e., IL-4 and IL-10, were up-regulated by ECK. Overall, this dramatic increase in numbers of splenocytes indicated that ECK could induce these cells to proliferate and could regulate the production of Th1- as well as Th2-type cytokines in immune cells. These results suggest that ECK has the immunomodulatory ability to activate the anti-inflammatory response and/or suppress the proinflammatory response, thereby endorsing its usefulness as therapy for diseases of the immune system.