Fasciola hepatica Excretory-Secretory Products (Fh-ES) Either Do Not Affect miRNA Expression Profile in THP-1 Macrophages or the Changes Are Undetectable by a Microarray Technique.

Fasciola hepatica is a liver fluke that resides in the bile ducts of various mammals. The parasitosis leads to economic losses in animal production estimated at USD 3.2 billion annually. It is also considered a zoonosis of great significance and a problem for public health affecting 2.4 million people worldwide. Nevertheless, besides the negative aspects of infestation, the antigens released by the fluke, F. hepatica Excretory-Secretory Products (Fh-ES) contain several immunomodulatory molecules that may be beneficial during the course of type I diabetes, multiple sclerosis, ulcerative colitis, or septic shock. This phenomenon is based on the natural abilities of adult F. hepatica to suppress proinflammatory responses. To underline the molecular basis of these mechanisms and determine the role of microRNA (miRNA) in the process, lipopolysaccharide (LPS)-activated THP-1 macrophages were stimulated with Fh-ES, followed by miRNA microarray analyses. Surprisingly, no results indicating changes in the miRNA expression profile were noted (p < 0.05). We discuss potential reasons for these results, which may be due to insufficient sensitivity to detect slight changes in miRNA expression or the possibility that these changes are not regulated by miRNA. Despite the negative data, this work may contribute to the future planning of experiments by other researchers.