Effector and regulatory dendritic cells display distinct patterns of miRNA expression

Expression and diagnostic value of miR-142-5p and miR-155-5p in the serum of children with allergic rhinitis

BACKGROUND

Recent studies have demonstrated that microRNAs (miRNAs) play an essential role in the regulation of allergic rhinitis (AR), but the underlying mechanism is still unclear.

OBJECTIVE

This case-control study aimed to measure the expression levels of serum miRNAs in children with AR, to evaluate their potential as diagnostic markers, and investigate the association between miRNAs and IL-4, total nasal symptom score (TNSS), and specific IgE (Artemisia).

METHODS

Twenty allergic rhinitis patients and 20 healthy controls were included. The expression levels of serum miR-18a-5p, miR-142-5p, miR-155-5p, and miR-3687 were measured using quantitative real-time polymerase chain reaction. Serum cytokine levels were measured using IL-4 enzyme-linked immunosorbent assay kits. Nasal symptoms were assessed using the TNSS. A receiver operating characteristic (ROC) curve was used to test the diagnostic ability of the study parameters.

RESULTS

The AR case group had a higher serum expression of miR-142-5p, miR-155-5p, and IL-4 than did the control group. However, there were no significant differences in the serum miR-18a-5p and miR-3687 expression levels between the two groups. We found that serum miR-142-5p and miR-155-5p levels were positively correlated with the expression of specific IgE (Artemisia). TNSS did not correlate with miR-142-5p or miR-155-5p levels. In addition, no significant correlation was identified between miR-142-5p and IL-4 expression, whereas miR-155-5p was positively correlated with IL-4 expression. The receiver operating characteristic curve did not look promising. The AUC was around 0.7 and it was not high enough for diagnostic tool.

CONCLUSION

The expression levels of serum miR-142-5p and miR-155-5p were upregulated in children with AR; however, they were insufficient as diagnostic tools for AR. MiR-155-5p may be involved in T helper type 2 cell-mediated immune response.

miRNA profiles change during grass pollen immunotherapy irrespective of clinical outcome

Background: Subcutaneous immunotherapy (SCIT) is widely used in the treatment of allergic rhinitis (AR). This study aimed to determine the expression of 48 miRNAs in patients with AR undergoing grass pollen SCIT and investigate relations with clinical outcomes. Methodology: Expression of selected miRNAs was determined using RT-PCR in the full blood of 16 patients with AR and seven healthy controls. Results: miR-136, miR-208 and miR-190 were upregulated in the AR group. After 6 months of SCIT, significant downregulation of some proinflammatory miRNAs and upregulation of several miRNAs regulating Th1/Th2 balance were found. No differences were found between good and poor responders. Conclusion: miRNAs may play a regulatory role in SCIT, leading to tolerance induction.

Mitochondria and immunity in chronic fatigue syndrome

It is widely accepted that the pathophysiology and treatment of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) could be considerably improved. The heterogeneity of ME/CFS and the confusion over its classification have undoubtedly contributed to this, although this would seem a consequence of the complexity of the array of ME/CFS presentations and high levels of diverse comorbidities. This article reviews the biological underpinnings of ME/CFS presentations, including the interacting roles of the gut microbiome/permeability, endogenous opioidergic system, immune cell mitochondria, autonomic nervous system, microRNA-155, viral infection/re-awakening and leptin as well as melatonin and the circadian rhythm. This details not only relevant pathophysiological processes and treatment options, but also highlights future research directions. Due to the complexity of interacting systems in ME/CFS pathophysiology, clarification as to its biological underpinnings is likely to considerably contribute to the understanding and treatment of other complex and poorly managed conditions, including fibromyalgia, depression, migraine, and dementia. The gut and immune cell mitochondria are proposed to be two important hubs that interact with the circadian rhythm in driving ME/CFS pathophysiology.

Upregulation of microRNA-155 Enhanced Migration and Function of Dendritic Cells in Three-dimensional Breast Cancer Microenvironment

Background: Dendritic cells (DCs) play an essential role in the induction and regulation of immune responses, including the activation of effector T lymphocytes for the eradication of cancers. However, the tumor microenvironment (TME) often leads to DCs dysfunction due to their immature state. MicroRNA-155 (miR-155) has emerged as a typical multifunctional gene regulator associated with immune system development and immune cell activation and differentiation.Methods: In this study, a three-dimensional TME model that closely mimics the microenvironment of breast cancer was prepared. MiR-155 overexpression and control vectors were constructed using lentivirus. The relative expression of miR-155 was determined by qRT-PCR. Cell viability, antigen uptake and cell surface marker expression were analyzed by live-dead staining and flow cytometry. The migration ability of bone marrow-derived DCs (BMDCs) was qualified by transwell assay. A mixed lymphocyte culture assay was used to assess T cell-specific proliferation. Cytokine levels were determined by ELISA.Results: We found that the expression of miR-155 in DCs was inhibited by the TME. Furthermore, upregulation of miR-155 enhanced the migration ability, uptake of antigen and elevated the expression of the mature DCs markers CD80 and MHCII. More importantly, overexpression of miR-155 in DCs significantly induced T cell proliferation and IFN-γ and IL-2 secretion.Conclusion: MiR-155 is a potential molecular regulator that may improve the efficacy of DCs-based tumor immunotherapy.

Searching for the Transcriptomic Signature of Immune Tolerance Induction-Biomarkers of Safety and Functionality for Tolerogenic Dendritic Cells and Regulatory Macrophages

The last years have witnessed a breakthrough in the development of cell-based tolerance-inducing cell therapies for the treatment of autoimmune diseases and solid-organ transplantation. Indeed, the use of tolerogenic dendritic cells (tolDC) and regulatory macrophages (Mreg) is currently being tested in Phase I and Phase II clinical trials worldwide, with the aim of finding an effective therapy able to abrogate the inflammatory processes causing these pathologies without compromising the protective immunity of the patients. However, there exists a wide variety of different protocols to generate human tolDC and Mreg and, consequently, the characteristics of each product are heterogeneous. For this reason, the identification of biomarkers able to define their functionality (tolerogenicity) is of great relevance, on the one hand, to guarantee the safety of tolDC and Mreg before administration and, on the other hand, to compare the results between different cell products and laboratories. In this article, we perform an exhaustive review of protocols generating human tolDC and Mreg in the literature, aiming to elucidate if there are any common transcriptomic signature or potential biomarkers of tolerogenicity among the different approaches. However, and although several effectors seem to be induced in common in some of the most reported protocols to generate both tolDC or Mreg, the transcriptomic profile of these cellular products strongly varies depending on the approach used to generate them.