Book Worms Aren’t the Only Smart Worms
...ate throughout the host. Often times, these eggs get trapped in the small sinusoids of the liver because of the large blood flow through this organ (1). The chronic disease, schistosomiasis, results from the immune response to accumulating eggs trapped in tissues. The interaction between the immune system and this pathogen is a complex and delicate balancing act. Certain host signals help guide the development of the schistosome and proteins have been identified in the parasites surface membrane that may act as receptors for these signals (2). Cells from the innate immune system, dendritic cells, respond to lipids from the schistosoma parasites. During this response the dendritic cells can initiate the development of regulatory T-cells and subsequently suppress the activity of other immune cells (1). Lipids on the schistosome surface membrane interact with toll-like receptors (TLRs). TLRs are cell surface receptors that recognize different classes of molecules such as lipopolysaccharrides. One lipid that is being studied is phosphatidylserine. Researchers at Leiden University are investigating the effects of schistosome lipids on the host immune response, specifically the lipid phosphatidylserine (4). To do this study, he lipids from Schistosoma manasoni were extracted and ran over and ion-exchange column. The fractions that contained phosphatidylserine were found to induce the development of T cells, in vitro, that secrete interleukin-10 (IL-10). IL-10 is an immunosuppressive cytokine. This effect was specific to phosphatidylserine because fractions that did not contain phosphatidylserine were unsuccessful in inducing IL-10 production (4). When looking more clos...