Inhibition of extracellular vesicle-encapsulated miRNA in systemic lupus erythematosus
Loading...
Date
2019-05
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
The Ohio State University
Abstract
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by chronic inflammation and systemic dysregulation of immune function. We have previously shown that toll-like receptor (TLR)7 and TLR8 are significantly up-regulated in peripheral blood mononuclear cells (PBMCs) of SLE patients. TLR7 and TLR8 bind single-stranded RNA to stimulate innate inflammatory responses, but recent studies have discovered that microRNAs (miRNAs) packaged and secreted in extracellular vesicles (EVs) can also activate these receptors. Our previous work has demonstrated that EV-derived miRNAs are differentially expressed in SLE patients compared to age/sex-matched healthy controls, with several upregulated miRNAs capable of activating TLR7/8. Specifically, we found miR-21, miR-29a, and miR-29b to be upregulated in SLE and/or lupus nephritis patients. The objective of this study was to explore the combinatorial immunomodulatory effects of miR-21, miR-29a, and miR-29b inhibition in a humanized model of murine SLE. In order to measure these effects, PBMCs from active SLE patients were intraperitoneally injected into immunodeficient NOD.Cg-Rag1tm1Mom Il2rgtm1Wjl/SzJ (NRG) mice to produce chimeras. Prior to injection, the PBMCs were transfected with complementary locked nucleic acid (LNA) miRNA antagonists for miR-21, miR-29a, and miR-29b or a miR-scramble control. After three weeks, blood was collected for flow cytometry and cytokine analysis via ELISA and tissue was collected for histopathological examination by H&E and immunohistochemistry (IHC). Human B-cells and T-cells (CD4+ and CD8+) were successfully recovered with no significant difference in levels between treatment groups. In addition, inflammatory responses detected by H&E in the kidney, liver, and small intestine were reduced with miRNA inhibition. IHC analysis confirmed a reduction in human CD3+ T-cell infiltration in the kidney, liver, and small intestine with miRNA inhibition. These results establish a novel chimeric mouse model to study the inhibition of EV-encapsulated miRNAs and to explore their therapeutic potential to suppress autoimmune-mediated inflammation in SLE.
Description
1st place in Molecular Genetics and Genomics section, 2019 Denman Undergraduate Research Forum
Keywords
Systemic lupus erythematosus, microRNA, therapeutic treatment, extracellular vesicles