64Cu and fluorescein labeled anti-miRNA peptide nucleic acids for the detection of miRNA expression in living cells

MiRNAs are single stranded RNAs of 18–22 nucleotides. They are promising diagnostic and prognostic markers for several pathologies including tumors, neurodegenerative, cardiovascular and autoimmune diseases. In the present work the development and characterization of anti-miRNA radiolabeled probes based on peptide nucleic acids (PNAs) for potential non-invasive molecular imaging in vivo of giant cell arteritis are described. MiR-146a and miR-146b-5p were selected as targets because they have been found up-regulated in this disease. Anti-miR and scramble PNAs were synthesized and linked to carboxyfluorescein or DOTA. DOTA-anti-miR PNAs were then labelled with copper-64 (⁶⁴Cu) to function as non-invasive molecular imaging tools. The affinity of the probes for the targets was assessed in vitro by circular dichroism and melting temperature. Differential uptake of fluorescein and ⁶⁴Cu labeled anti-miRNA probes was tested on BCPAP and A549 cell lines, expressing different levels of miR-146a and -146b-5p. The experiments showed that the anti-miR-146a PNAs were more effective than the anti-miR-146b-5p PNAs. Anti-miR-146a PNAs could bind both miR-146a and miR-146b-5p. The uptake of fluorescein and ⁶⁴Cu labeled anti-miR-146a PNAs was higher than that of the negative control scramble PNAs in miRNA expressing cells in vitro. ⁶⁴Cu-anti-miR-146a PNAs might be further investigated for non-invasive PET imaging of miR-146 overexpressing diseases.

The therapeutic potential of tuftsin-phosphorylcholine in giant cell arteritis

Tuftsin-PhosphorylCholine (TPC) is a novel bi-specific molecule which links tuftsin and phosphorylcholine. TPC has shown immunomodulatory activities in experimental mouse models of autoimmune diseases. We studied herein the effects of TPC ex vivo on both peripheral blood mononuclear cells (PBMCs) and temporal artery biopsies (TABs) obtained from patients with giant cell arteritis (GCA) and age-matched disease controls. GCA is an immune-mediated disease affecting large vessels. Levels of 18 cytokines in supernatants, PBMC viability, T helper (Th) cell differentiation of PBMCs and gene expression in TABs were analyzed. Treatment ex vivo with TPC decreased the production of IL-1β, IL-2, IL-5, IL-6, IL-9, IL-12(p70), IL-13, IL-17A, IL-18, IL-21, IL-22, IL-23, IFNγ, TNFα, GM-CSF by CD3/CD28 activated PBMCs whereas it negligibly affected cell viability. It reduced Th1 and Th17 differentiation while did not impact Th22 differentiation in PBMCs stimulated by phorbol 12-myristate 13-acetate plus ionomycin. In inflamed TABs, treatment with TPC down-regulated the production of IL-1β, IL-6, IL-13, IL-17A and CD68 gene expression. The effects of TPC were comparable to the effects of dexamethasone, included as the standard of care, with the exception of a greater reduction of IL-2, IL-18, IFNγ in CD3/CD28 activated PBMCs and CD68 gene in inflamed TABs. In conclusion our results warrant further investigations regarding TPC as an immunotherapeutic agent in GCA and potentially other autoimmune and inflammatory diseases.

Higher Frequencies of Lymphocytes Expressing the Natural Killer Group 2D Receptor in Patients With Behçet Disease

Behçet disease (BD) is an inflammatory systemic disease with a fluctuating course, which can affect the skin, eyes, central nervous system, musculoskeletal, gastrointestinal, and vascular systems. No laboratory tests are currently available for the diagnosis of BD and monitoring disease activity. Moreover there is a lack of knowledge on BD pathogenesis. This study focused on circulating Natural Killer (NK), NKT and T cells evaluated as CD3^neg CD56^pos, CD3^pos CD56^pos, and CD3^pos CD56^neg. Peripheral blood mononuclear cells (PBMCs) were collected from 38 BD patients and 20 healthy controls (HC). The frequencies of NK, NKT, and T cells expressing CD16, CD69, NKG2D, Nkp30, Nkp46, and NKG2A were assessed by flow cytometry. Cytotoxic potential of NK cells was evaluated by flow cytometry as the percentage of cells expressing the degranulation marker CD107a after incubation with K562 cells. The levels of 27 cytokines were determined in plasma with a multiplex bead-based assay. Higher percentages of NK, NKT, and T cells expressing NKG2D were detected in PBMCs of BD patients than HC. ROC curve analysis showed that the evaluation of NKG2D^pos NK, NKT, and T cell percentages discriminated between BD patients and HC. Moreover, there was a positive correlation between the BD Current Activity Form (BDCAF) scores and the frequencies of NKG2D^pos NK and NKT cells. A higher frequency of NK cells expressing CD107a was induced in PBMCs from BD patients than HC after incubation with K562 cells. Concentrations of IL-5, IL-6, IL-10, IL-13, IP-10, and MIP-1β were higher in plasma of BD patients than HC. Monitoring the frequencies of NKG2D^pos lymphocytes could help the clinicians in BD patients management. In addition, the increased expression of NKG2D in BD patients is likely involved in disease pathogenesis.

Increased expression of interleukin-22 in patients with giant cell arteritis

Objectives

GCA is characterized by arterial remodelling driven by inflammation. IL-22 is an attractive cytokine which acts at the crosstalk between immune and stromal cells. We hypothesized that IL-22 might be induced in GCA and might be involved in disease pathogenesis.

Methods

Patients subjected to temporal artery biopsies (TABs) naïve from therapy were enrolled: 27 biopsy-proven GCA, 8 biopsy-negative GCA, 21 biopsy-negative non-GCA patients. Expression of IL-22 was determined in TABs by immunohystochemistry, in plasma by ELISA, in peripheral blood mononuclear cells by real-time PCR and flow cytometry. Effects of IL-22 on viability and gene expression of primary cultures obtained from TABs were also evaluated.

Results

Inflamed TABs from GCA patients showed a higher expression of IL-22 and IL-22 specific receptor subunit (IL-22R1) than non-inflamed TABs. IL-22 was expressed in infiltrating immune cells and spindle shaped cells, IL-22R1 was expressed in endothelial cells. Patients with biopsy-proven GCA showed increased levels of IL-22 in plasma than patients with biopsy-negative GCA, without GCA and healthy subjects. Peripheral blood mononuclear cells from GCA patients expressed higher IL-22 transcript than healthy subjects. After stimulation in vitro with phorbol 12-myristate 13-acetate and ionomycin, the frequencies of Th22 and IL-22+ CD4+ lymphocytes were similar between patients with and without GCA. Treatment with IL-22 of primary cultures obtained from TABs increased cell viability under stress conditions and expression of B-cell activating factor.

Conclusion

IL-22 is increased in patients with GCA and affects viability and gene expression of arterial cells, supporting a potential role in disease pathogenesis.

No detection of varicella-zoster virus in temporal arteries of patients with giant cell arteritis

OBJECTIVE

Data on the presence of varicella-zoster virus (VZV) in temporal arteries of patients with giant cell arteritis (GCA) are controversial. We analyzed VZV infection in temporal arteries from Italian patients with temporal artery biopsy (TAB)-positive GCA, TAB-negative GCA, and controls.

METHODS

A total of 79 formalin-fixed, paraffin-embedded (FFPE) TABs performed between 2009 and 2012 at a single institution from 34 TAB-positive GCA patients, 15 TAB-negative GCA patients, and 30 controls were retrieved. Six 5-μm sections of all FFPE TABs were cut. The first section was analyzed by immunohistochemistry using mouse monoclonal anti-VZVgE IgG1 antibody. DNA was extracted from the remaining five sections and analyzed by real-time polymerase chain reaction (PCR) for the presence of VZV DNA. For 10 of the 34 TAB-positive GCA patients, an additional 2-mm piece of frozen TAB was available. DNA was extracted from the entire 2-mm length frozen specimen and analyzed by PCR for the presence of VZV DNA. Thirty additional 5-μm sections were cut from the FFPE TABs of these 10 patients and analyzed by immunohistochemistry for the presence of VZV antigen.

RESULTS

Immunohistochemical analysis detected VZV antigen in 1/34 (3%) TAB-positive GCA, 0/15 TAB-negative GCA, and 0/30 controls, and in none of the 300 sections cut from the 10 FFPE TABs positive for GCA for which the frozen specimens were available. DNA obtained from all TABs was amplifiable. VZV DNA was neither found in any of the FFPE TABs nor found in frozen TABs.

CONCLUSION

Our data do not support in Italian patients a possible role for VZV infection in the etiopathogenesis of GCA.

MicroRNA markers of inflammation and remodelling in temporal arteries from patients with giant cell arteritis

OBJECTIVES

There is increasing evidence that microRNAs (miRNAs) are deregulated in autoimmune and cardiovascular diseases. The present study aimed to identify if miRNAs are deregulated in giant cell arteritis (GCA), a vasculitis affecting large-sized and medium-sized arteries, and to determine if miRNA levels might allow to discriminate between patients with GCA and those without.

METHODS

58 patients who had temporal artery biopsy (TAB) for suspected GCA were included in the study and divided into three groups: patients with TAB-positive GCA showing a transmural inflammation (n=27), patients with TAB-negative GCA (n=8) and TAB-negative non-GCA patients with a final diagnosis different from GCA (n=23). To identify candidate miRNAs deregulated in GCA, we profiled the expression of 1209 miRNAs in inflamed TABs and normal TABs. Selected miRNAs were then validated by real-time PCRs and in situ hybridisation (ISH).

RESULTS

MiR-146b-5p, -146a, -155, -150, -21 and -299-5p were significantly more expressed in inflamed TABs from patients with GCA. miRNAs were mainly deregulated at the tissue level because peripheral blood mononuclear cells and polymorphonuclear cells from the three groups of patients and age-matched healthy controls had similar levels of miRNAs. ISH showed that miR-21 was mainly expressed by cells in the medial and intimal layers of inflamed TABs. Patients with TAB-negative GCA had a miRNA profile similar to TAB-negative non-GCA patients.

CONCLUSIONS

MiR-146b-5p, -146a, -21, -150, -155, -299-5p are overexpressed in the presence of inflammation in TABs from patients with GCA.

Italian multicentre study for application of a diagnostic algorithm in autoantibody testing for autoimmune rheumatic disease: conclusive results

AIM

The presence of specific auto-antibodies in serum (i.e., antinuclear antibodies or ANA, anti-extractable nuclear antigens or anti-ENA, and anti-double stranded DNA or anti-dsDNA ) is one of the major criteria in the diagnostics of Autoimmune Rheumatic Disease. As such, the request for these tests has grown exponentially in laboratory practice. The aim of this study is to describe the implementation of a joint laboratory-clinics guideline for reducing clinically inappropriate requests for autoantibody testing in a broad geographic area (Parma, Modena, Piacenza, Reggio-Emilia) for the diagnosis of Autoimmune Rheumatic Disease.

METHODS

This study, supported by a Regional grant for innovative research projects started in January 2008, is an observational research aimed at comparing the number of ANA, anti-dsDNA and anti-ENA testing as well as the percentage of positive test results before and after implementation of the diagnostic algorithm in hospitalized patients. A multidisciplinary team consisting of clinical immunologist and laboratory scientists was established, with the aim of collecting and analysing diagnostic criteria, clinical needs, laboratory report formats, analytical procedures, as well as the number of tests performed. The laboratory results and the clinical protocol were both validated by data emerging from the clinical follow-up studies.

RESULTS

A joint guideline for auto-antibody testing, placing ANA test at the first level, has been developed and implemented since January 2009. The results for the period January-June 2009 (12,738 tests) were compared with those of the same period in 2008 (13,067 tests). A significant reduction in the number of anti-dsDNA (-26%) and anti-ENA (-15%) was observed. The percentage of second-level tests positivity after implementation of the diagnostic protocol had also consistently increased for both ENA (13% vs 17%) and dsDNA (9% vs 11%).

DISCUSSION

The development and implementation of algorithms for the diagnostics of Autoimmune Rheumatic Disease in hospitalized patients was associated with a reduction in the number of second-level tests, but also with an increased diagnostic specificity. This outcome attests that close collaboration and audit between clinicians, laboratory specialists and healthcare services is effective to develop efficient diagnostic algorithms for both hospitalized patients and outpatients.

Galactomannan detection in Geotrichum capitatum invasive infections: report of 2 new cases and review of diagnostic options

We report 2 cases of Geotrichum capitatum infection in leukemia patients for which Aspergillus galactomannan (GM) assay was positive. The diagnostic options of G. capitatum infections in hematologic patients were reviewed. Although the pathogen was isolated from blood in 77% of cases, diagnostic difficulties remain and GM assay may have a role.