An Investigation of Innate Immune Response of Human Blood Macrophage to Sense and Antisense dsRNA

Abstract

Silencing of gene expression by siRNA (small interfering RNA) is a powerful approach used to study the genetic analysis and functional roles of mammalian genes. There is at present no report about the effects of mammalian two-hybrid system plasmids delivery of sense and antisense strands. The leishmania pteridine reductase 1 (PTR1) gene was cloned as sense and antisense strands into mammalian two hybrid system plasmids. The constructs were transfected into human blood macrophages on the basis of eight experimental groups. (Antisense strand ± LPS, sense strand ± LPS, dsRNA ± LPS, negative control ± LPS). After 24 hours, cytokines production was assessed with ELISA. Transfection of sense and antisense strand RNA into monocyte-derived macrophages (MDM) was confirmed by RT-PCR. Single strands RNA expressed IL-8, IL-12, IL-1β inflammatory cytokines and dsRNA induced IL-8, IL-12 and TNF-α production in MDM. In contrast, random uptake from a mixture of two plasmids was downregulated IL-8, IL-12, IFN-γ cytokines, with a significant difference of p<0.05 in macrophage.With respect to the increased level of IL-8 in macrophage detected in single strand groups, the chemokine production—as a major feature of innate immunity—is a powerful tool for evaluation of sense/antisense in experimental and therapeutic gene vaccine delivery. siRNA–based gene therapy could have great potential in cancer treatment. Highlights siRNA (small interfering RNA) is powerful approach to study the functional roles of mammalian genes. dsRNA induced antiviral response by induction of different cytokines including TNF-α, IL-12 and IL-8. dsRNA showed promising results as a vaccine adjuvant for both antiviral and antitumor prophylaxis. The strong response of IL-8 chemokine indicated the linkage between innate immunity and adaptive immunity in progressive malignances.