The role of Killer immunoglobulin-like receptors (KIRs) in the genetic susceptibility to non-celiac wheat sensitivity (NCWS).

OBJECTIVES: Non-celiac wheat sensitivity (NCWS) is an emerging clinical condition characterized by gastrointestinal and extraintestinal symptoms following the ingestion of gluten-containing foods in patients without celiac disease (CD) or wheat allergy. Despite the great interest for NCWS, the genetic risk factors still need to be fully clarified. In this study, we first assessed the possible contribution of KIR genes and KIR haplotypes on the genetic predisposition to NCWS. METHODS: Fifty patients with NCWS, 50 patients with CD, and 50 healthy controls (HC) were included in this study. KIR genes and KIR genotyping were investigated in all subjects by polymerase chain reaction with the sequence oligonucleotide probe (PCR-SSOP) method using Luminex technology. RESULTS: We found a statistically different distribution of some KIR genes among NCWS, CD, and HC. Specifically, NCWS showed a decreased frequency of KIR2DL1, -2DL3, -2DL5, -2DS2, -2DS3, -2DS4, -2DS5, and -3DS1 genes, and an increased frequency of -3DL1 gene respect to both CD and HC. No difference was detected in the KIR haplotype expression. At the multivariate analysis, KIR2DL5, -2DS4, and -2DS5 were independent predictors of NCWS. CONCLUSIONS: Our findings suggest a role of KIR genes in NCWS susceptibility, with KIR2DL5, -2DS4, and -2DS5 having a protective effect. Further large-scale multicentric studies are required to validate these preliminary findings.

Molecular Biomarkers of Neurodegenerative Disorders: A Practical Guide to Their Appropriate Use and Interpretation in Clinical Practice.

Neurodegenerative disorders (NDs) represent a group of different diseases characterized by the progressive degeneration and death of the nervous system's cells. The diagnosis is challenging, especially in the early stages, due to no specific clinical signs and symptoms. In this context, laboratory medicine could support clinicians in detecting and differentiating NDs. Indeed, biomarkers could indicate the pathological mechanisms underpinning NDs. The ideal biofluid for detecting the biomarkers of NDs is cerebrospinal fluid (CSF), which has limitations, hampering its widespread use in clinical practice. However, intensive efforts are underway to introduce high-sensitivity analytical methods to detect ND biomarkers in alternative nonivasive biofluid, such as blood or saliva. This study presents an overview of the ND molecular biomarkers currently used in clinical practice. For some diseases, such as Alzheimer's disease or multiple sclerosis, biomarkers are well established and recommended by guidelines. However, for most NDs, intensive research is ongoing to identify reliable and specific biomarkers, and no consensus has yet been achieved.

Microglial Activation and Priming in Alzheimer's Disease: State of the Art and Future Perspectives.

Alzheimer's Disease (AD) is the most common cause of dementia, having a remarkable social and healthcare burden worldwide. Amyloid ß (Aß) and protein Tau aggregates are disease hallmarks and key players in AD pathogenesis. However, it has been hypothesized that microglia can contribute to AD pathophysiology, as well. Microglia are CNS-resident immune cells belonging to the myeloid lineage of the innate arm of immunity. Under physiological conditions, microglia are in constant motion in order to carry on their housekeeping function, and they maintain an anti-inflammatory, quiescent state, with low expression of cytokines and no phagocytic activity. Upon various stimuli (debris, ATP, misfolded proteins, aggregates and pathogens), microglia acquire a phagocytic function and overexpress cytokine gene modules. This process is generally regarded as microglia activation and implies that the production of pro-inflammatory cytokines is counterbalanced by the synthesis and the release of anti-inflammatory molecules. This mechanism avoids excessive inflammatory response and inappropriate microglial activation, which causes tissue damage and brain homeostasis impairment. Once the pathogenic stimulus has been cleared, activated microglia return to the naïve, anti-inflammatory state. Upon repeated stimuli (as in the case of Aß deposition in the early stage of AD), activated microglia shift toward a less protective, neurotoxic phenotype, known as "primed" microglia. The main characteristic of primed microglia is their lower capability to turn back toward the naïve, anti-inflammatory state, which makes these cells prone to chronic activation and favours chronic inflammation in the brain. Primed microglia have impaired defence capacity against injury and detrimental effects on the brain microenvironment. Additionally, priming has been associated with AD onset and progression and can represent a promising target for AD treatment strategies. Many factors (genetics, environmental factors, baseline inflammatory status of microglia, ageing) generate an aberrantly activated phenotype that undergoes priming easier and earlier than normally activated microglia do. Novel, promising targets for therapeutic strategies for AD have been sought in the field of microglia activation and, importantly, among those factors influencing the baseline status of these cells. The CX3CL1 pathway could be a valuable target treatment approach in AD, although preliminary findings from the studies in this field are controversial. The current review aims to summarize state of the art on the role of microglia dysfunction in AD pathogenesis and proposes biochemical pathways with possible targets for AD treatment.

Monocyte distribution width (MDW) as a screening tool for early detecting sepsis: a systematic review and meta-analysis.

OBJECTIVES: Monocyte distribution has recently emerged as a promising biomarker of sepsis, especially in acute setting, such as Emergency Department and Intensive Care Unit. This study aimed to evaluate the accuracy of monocyte distribution width (MDW) for early detecting patients with sepsis by performing a systemic review and meta-analysis of published studies. METHODS: Relevant publications were identified by a systematic literature search on PubMed and Google Scholar from inception to September 07, 2021. Studies were divided into two groups based on the sepsis criteria applied, namely sepsis-2 or sepsis-3. RESULTS: Ten studies including 9,475 individuals, of whom 1,370 with sepsis (742 according Sepsis-2 and 628 according to Sepsis-3), met the inclusion criteria for our meta-analysis. The pooled sensitivity and specificity were 0.789 and 0.777 for Sepsis-2 criteria, 0.838 and 0.704 for Sepsis-3 criteria. CONCLUSIONS: MDW represents a reliable biomarker for sepsis screening.

A new tool for sepsis screening in the Emergency Department.

OBJECTIVES: In this study, we developed and evaluated the diagnostic accuracy of the Sepsis Index for early sepsis screening in the Emergency Department (ED). METHODS: Sepsis Index is based on the combination of monocyte distribution width (MDW) and mean monocyte volume (MMV). Sepsis Index≥1 was selected to define sepsis. We tested its diagnostic accuracy in an ED population stratified in four groups: controls, Systemic Inflammatory Response Syndrome (SIRS), infection, and sepsis, according to Sepsis-2 criteria. RESULTS: Patients with sepsis displayed higher median Sepsis Index value than patients without sepsis. At the receiver operating characterictis (ROC) curve analysis for the prediction of sepsis, the area under the curve (AUC) of MDW and Sepsis Index were similar: 0.966 (95%CI 0.947-0.984), and 0.964 (95%CI 0.942-0.985), respectively. Sepsis Index showed increased specificity than MDW (94.7 vs. 90.6%), without any decrease in sensitivity (92.0%). Additionally, LR+ increased from 9.8 (MDW) to 17.4 (Sepsis Index), without any substantial change in LR- (respectively 0.09 vs. 0.08). Finally, PPV increased from 0.286 (MDW) to 0.420 (Sepsis Index). CONCLUSIONS: Sepsis Index improves the diagnostic accuracy of MDW alone for sepsis screening.

Vitamin D and Genetic Susceptibility to Multiple Sclerosis.

Multiple sclerosis (MS) is an autoimmune disease affecting the central nervous system (CNS), resulting from the interaction among genetic, epigenetic, and environmental factors. Vitamin D is a secosteroid, and its circulating levels are influenced by environment and genetics. In the last decades, research data on the association between MS and vitamin D status led to hypothesize a possible role for hypovitaminosis D as a risk factor for MS. Some gene variants encoding proteins involved in vitamin D metabolism, transport, and function, which are responsible for vitamin D status alterations, have been related to MS susceptibility. This review explores the current literature on the influence of vitamin D-related genes in MS susceptibility, reporting all single-nucleotide polymorphisms (SNPs) investigated to date in 12 vitamin D pathway genes. Among all, the gene codifying vitamin D receptor (VDR) is the most studied. The association between VDR SNPs and MS risk has been reported by many Authors, with a few studies producing opposite results. Other vitamin D-related genes (including DHCR7/NADSYN1, CYP2R1, CYP27A1, CYP3A4, CYP27B1, CYP24A1, Megalin-DAB2-Cubilin, FGF-23, and Klotho) have been less investigated and achieved more conflicting evidence. Taken together, findings from the studies reviewed cannot clarify whether and to what extent vitamin D-related gene variants can influence MS risk.

Monocyte distribution width (MDW) as a screening tool for sepsis in the Emergency Department.

Objectives The diagnosis of sepsis in the Emergency Department (ED) is challenging and a reliable biomarker is needed. The current study aimed to evaluate the diagnostic accuracy of monocyte distribution width (MDW) for the early identification of sepsis in the ED. Methods We performed a large observational study including consecutive adult patients (≥18 years of age) presenting to the ED between September and November 2019, with an order for complete blood count (CBC) evaluation. A total of 2,215 patients were enrolled and classified based on Sepsis-2 criteria as the control group (1,855), infection group (172), Systemic Inflammatory Response Syndrome (SIRS) group (100), and sepsis group (88). Results MDW levels were higher in patients with sepsis than in all other groups (p<0.001). ROC curve analysis showed an optimal diagnostic accuracy of MDW for sepsis prediction at a cut-off point of 23.5, with an AUC of 0.964, sensitivity and specificity of 0.920 and 0.929, respectively. Conclusions Our findings encourage further investigation to validate the use of MDW as a screening tool for the early identification of patients at risk of sepsis in the ED.

Vitamin D increases the production of IL-10 by regulatory T cells in patients with systemic sclerosis.

OBJECTIVES: Vitamin D status influences the risk to develop autoimmune diseases affecting the percentage and/or functions of regulatory T cells (Tregs). Since low levels of 25 (OH) D have been decreased in patients with systemic sclerosis (SSc), we aimed to study the effect of Vitamin D3 (cholecalciferol) supplementation on Tregs frequencies and functions. METHODS: Peripheral blood and sera samples were obtained from 45 SSc patients and controls (HC). A number of eighteen SSc patients had consumed Cholecalciferol (orally) at the dose of 25.000 UI/month for 6 months at the time of enrollment. 25(OH)D serum levels were measured and VDR polymorphisms, were genotyped by polymerase chain reaction (PCR). Tregs isolated from peripheral blood mononuclear cells were in vitro expanded and a suppression assay was performed. Flow cytometry analysis was then carried out. Finally, IL-10 production was assayed by ELISA. RESULTS: Low serum levels of 25(OH)D were detected in SSc patients. The percentage of Tregs in SSc patients was similar to controls, but, among SSc patients, it was higher in those patients taking cholecalciferol. Tregs capability to suppress T cell proliferation was impaired in SSc patients and not restored after in vitro pre-treatment with the active form of Vitamin D (1,25(OH)2D3); but at the same time the production of IL-10 was increased in treated samples obtained from patients. The lack of response of Tregs from SSc patients to 1,25(OH)2D3 treatment in vitro was not due to altered Vitamin D/VDR signalling. CONCLUSIONS: Altogether, our results indicate that the increased production of IL-10 by 1,25(OH)2D3 -treated Tregs could provide a "suppressive" cytokine milieu able to modulate immune response but it is not sufficient to restore the immune suppressive functions of Tregs.

Reference interval by the indirect approach of serum thyrotropin (TSH) in a Mediterranean adult population and the association with age and gender.

Background The serum concentration of thyrotropin (TSH) represents a first-line test in diagnostic algorithms. The estimation of TSH reference intervals (RIs) is still a matter of debate due to the high prevalence of subclinical disease making difficult the definition of truly healthy subjects. The aim of this study was to estimate TSH RIs in healthy subjects and to evaluate the effect of age and gender on TSH concentration. Methods Forty-four thousand one hundred and fifty-six TSH data were collected between July 2012 and April 2018 at the Department of Laboratory Medicine, University-Hospital, Palermo. Common and sex-specific RIs were estimated by Arzideh's indirect method after exclusion of individuals younger than 15 years, subjects with repeated TSH tests and with abnormal free thyroxine (fT4), free triiodothyronine (fT3) or anti-thyroid-peroxidase antibodies. The combined effect of age and gender on TSH values was evaluated. Results RIs estimated in the selected individuals (n = 22602) were, respectively, 0.18-3.54 mIU/L (general), 0.19-3.23 mIU/L (men) and 0.18-3.94 mIU/L (women). Women showed significantly higher median TSH than men (1.46 vs. 1.39 mIU/L; p < 0.0001). Both in men and in women, median TSH decreased along with age; however, although up to 60 years in both men and women showed similar values, afterwards women showed constantly higher TSH than men. Accordingly, statistical analysis showed a significant interaction between gender and age (p = 0.001), suggesting that the effect of age on TSH is different between genders. Conclusions Our findings suggest that the indirect method, with appropriate cleaning of data, could be useful to define TSH RIs.

Fructose-1,6-Bisphosphate Protects Hippocampal Rat Slices from NMDA Excitotoxicity.

Effects of fructose 1,6-bisphosphate (F-1,6-P2) towards N-methyl-d-aspartate NMDA excitotoxicity were evaluated in rat organotypic hippocampal brain slice cultures (OHSC) challenged for 3 h with 30 µM NMDA, followed by incubations (24, 48, and 72 h) without (controls) and with F-1,6-P2 (0.5, 1 or 1.5 mM). At each time, cell necrosis was determined by measuring LDH in the medium. Energy metabolism was evaluated by measuring ATP, GTP, ADP, AMP, and ATP catabolites (nucleosides and oxypurines) in deproteinized OHSC extracts. Gene expressions of phosphofructokinase, aldolase, and glyceraldehyde-3-phosphate dehydrogenase were also measured. F-1,6-P2 dose-dependently decreased NMDA excitotoxicity, abolishing cell necrosis at the highest concentration tested (1.5 mM). Additionally, F-1,6-P2 attenuated cell energy imbalance caused by NMDA, ameliorating the mitochondrial phosphorylating capacity (increase in ATP/ADP ratio) Metabolism normalization occurred when using 1.5 mM F-1,6-P2. Remarkable increase in expressions of phosphofructokinase, aldolase and glyceraldehyde-3-phosphate dehydrogenase (up to 25 times over the values of controls) was also observed. Since this phenomenon was recorded even in OHSC treated with F-1,6-P2 with no prior challenge with NMDA, it is highly conceivable that F-1,6-P2 can enter into intact cerebral cells producing significant benefits on energy metabolism. These effects are possibly mediated by changes occurring at the gene level, thus opening new perspectives for F-1,6-P2 application as a useful adjuvant to rescue mitochondrial metabolism of cerebral cells under stressing conditions.

Non-Skeletal Activities of Vitamin D: From Physiology to Brain Pathology.

Vitamin D is a secosteroid hormone regulating the expression of almost 900 genes, and it is involved in the regulation of calcium and phosphate metabolism, immune response, and brain development. Low blood vitamin D levels have been reported in patients affected by various diseases. Despite a large amount of literature data, there is uncertainty surrounding the role of vitamin D as a serum biomarker in Alzheimer's disease (AD) and Parkinson's disease (PD). Indeed, the lack of internationally recognized 25(OH)D3 reference measurement procedures and standard materials in the past led to unstandardized serum total 25(OH)D3 results among research and clinical care laboratories. Thus, most of the literature studies reported unstandardized data, which are of little use and make it difficult to draw conclusions of the role of vitamin D in AD and PD. This review summarizes the extra-skeletal actions of vitamin D, focusing its role in immunomodulation and brain function, and reports the issue of lacking standardized literature data concerning the usefulness of vitamin D as a biomarker in AD and PD.

Association of CYP2R1 rs10766197 with MS risk and disease progression.

BACKGROUND: MS is a neurodegenerative autoimmune disease resulting from a complex interaction of genetic and environmental factors. Among these, vitamin D and genetic variants associated with vitamin D-metabolism gain great attention. The aim of our study was to assess five SNPs in NADSYN1 and CYP2R1 genes in relation to serum 25-OH-vitamin D3 levels in MS patients and controls. METHODS: 25-OH-vitamin D3 levels and genotyping of CYP2R1- and NADSYN1-SNPs were investigated both in MS patients and in healthy controls. RESULTS: The analysis revealed lower 25-OH-vitamin D3 concentrations in MS patients than in controls and an association of rs10766197 CYP2R1 SNP with MS risk. After stratifying MS patients according to gender, we found that the minor allele A of rs10766197 had a higher frequency in men in comparison to women affected by MS. Additionally, the presence of allele A in men was associated with disease progression, assessed by EDSS and MSSS scores. CONCLUSION: The findings of our study open new perspectives for a role of CYP2R1 in both risk and progression of MS, with sex-related differences.

Heart-type fatty acid binding protein is a sensitive biomarker for early AMI detection in troponin negative patients: a pilot study.

BACKGROUND: Early detecting AMI in individuals presenting to the ED with chest pain continues to be a challenge. cTn is the gold standard for AMI diagnosis but early presenters (<1 hours from symptom onset) maybe cTn negative on admission. We analysed the diagnostic value of h-FABP and hs-TnI in patients presenting to ED with chest pain and no cTnI elevations. METHODS: 28 AMI and 28 no-AMI individuals both presented to ED within one hour from pain onset were included. Blood donors were analysed for h-FABP cut-off identification. Among AMI patients, 55% were positive for h-FABP and 34.6% were positive for hs-TnI (p = .015), thus 21% were positive only for h-FABP. The diagnostic accuracy was assessed by ROC curve. h-FABP showed a higher sensitivity but lower specificity than hs-TnI. CONCLUSIONS: In our study, the frequency of h-FABP positivity among AMI patients was higher than that of hs-TnI, which would have missed six of them; however, hs-TnI AUC was superior to that of h-FABP. These preliminary findings might confirm that h-FABP may be a good candidate for AMI rule-in/rule-out within the ED context.

Fetuin-A is Associated to Serum Calcium and AHSG T256S Genotype but Not to Coronary Artery Calcification.

Vascular calcification has been recently associated to an increased cardiovascular risk and mortality. In few studies, Fetuin-A showed an association to coronary artery calcification (CAC), although the physiopathological mechanism underlying this association has not been fully established yet. Seventy-four patients with one or more cardiovascular risk factor and asymptomatic for coronary vasculopathy were included in the study. CAC was evaluated by Agatston score. Serum Fetuin-A levels were determined by ELISA. Molecular analysis of AHSG T256S gene variant (rs4918) was performed by PCR-RFLP. Serum Fetuin-A was correlated to serum calcium (r = 0,321; P = 0,018), but not to serum phosphorous. Multivariate linear regression analysis confirmed this association and showed that calcium and AHSG genotype were independent predictors of Fetuin-A (P = 0.037, P = 0.014, respectively). In particular, subjects carrying the SS genotype had lower levels of Fetuin-A and calcium (P = 0.037 and P = 0.038, respectively). When we compare subjects with CAC 0-10 with subjects with CAC > 10, we found that only age and male gender (P < 0.001, P = 0.035, respectively), but not Fetuin-A, were associated to CAC. Fetuin-A is not associated to CAC in subjects with low cardiovascular risk profile and asymptomatic for coronary vasculopathy, suggesting that in this setting Fetuin-A, although correlated to serum levels of calcium, could be not involved in mineral deposition on coronary vessels.

Efficacy of Rapamycin as Inducer of Hb F in Primary Erythroid Cultures from Sickle Cell Disease and ß-Thalassemia Patients.

Phenotypic improvement of hemoglobinopathies such as sickle cell disease and ß-thalassemia (ß-thal) has been shown in patients with high levels of Hb F. Among the drugs proposed to increase Hb F production, hydroxyurea (HU) is currently the only one proven to improve the clinical course of these diseases. However, Hb F increase and patient's response are highly variable, indicating that new pharmacological agents could be useful for patients not responding to HU or showing a reduction of response during long-term therapy. In this study we evaluated the efficacy of rapamycin, a lypophilic macrolide used for the prevention of acute rejection in renal transplant recipients, as an inducer of Hb F production. The analyses were performed in cultured erythroid progenitors from 25 sickle cell disease and 25 ß-thal intermedia (ß-TI) patients. The use of a quantitative Real-Time-polymerase chain reaction ReTi-PCR technique and high performance liquid chromatography (HPLC) allowed us to determine the increase in γ-globin mRNA expression and Hb F production in human erythroid cells treated with rapamycin. The results of our study demonstrated an increase in vitro of γ-globin mRNA expression in 15 sickle cell disease and 14 ß-TI patients and a corresponding Hb F increase. The induction by rapamycin, even if lower or similar in most of samples analyzed, in some cases was higher than HU. These data suggest that rapamycin could be a good candidate to be used in vivo for the treatment of hemoglobinopathies.

Quantification of HBG mRNA in primary erythroid cultures: prediction of the response to hydroxyurea in sickle cell and beta-thalassemia.

BACKGROUND AND OBJECTIVE: Increased expression of fetal hemoglobin (HbF) may ameliorate the clinical course of hemoglobinopathies like sickle cell disease (SCD) and ß-thalassemia. Hydroxyurea (HU) can stimulate HbF production in these diseases but the response is highly variable indicating the utility of developing an in vitro test to predict the patient's response to HU. We assessed whether the HbF response of patients with SCD and thalassemia intermedia (TI) to HU correlates with HBG (both γ-globin genes) expression in their cultured erythroid progenitors following exposure to HU. PATIENTS AND METHODS: We exposed primary erythroid cultures from peripheral blood mononuclear cells from 30 patients with SCD and 15 with TI to HU and measured HBG mRNA by real-time quantitative PCR. The same patients were then treated with HU and their HbF response after treatment with a stable dose of HU was compared with the mRNA results in cultured cells. RESULTS AND CONCLUSION: The fold increase in HBG mRNA in erythroid progenitors was similar to the fold increase in HbF in vivo. Quantification of HBG mRNA in erythroid progenitor cell cultures from patients with SCD and TI is predictive of their clinical response to HU.

Exploring the effect of APOE ε4 on biomarkers of neurodegeneration in Alzheimer's disease.

BACKGROUND AND AIMS: This study aims to assess the association between APOE genotype and biomarkers of neurodegeneration in Alzheimer's disease (AD). METHODS: We performed a retrospective observational study at the University Hospital "P. Giaccone" in Palermo, Italy. We enrolled patients with cognitive decline, including AD. For each patient, we measured amyloid beta (Aß)42, Aß40, tau protein phosphorylated at threonine 181 (pTau), total tau (tTau), neurogranin, alpha-synuclein, and neurofilament light chain (NfL) in cerebrospinal fluid (CSF). RESULTS: The study population consisted of 194 patients (123 AD and 71 non-AD). AD patients have significantly lower Aß42 levels and Aß42/40 ratio and higher pTau, tTau, and NfLs levels than non-AD patients. In AD patients, the APOEε4 allele is associated with a significantly lower Aß42/40 ratio and higher levels of pTau, tTau, neurogranin, and alpha-synuclein. This association is not observed in non-AD patients. CONCLUSIONS: This study provides evidence of the significant impact of the APOE ε4 allele on neurodegenerative biomarkers in AD patients, highlighting its role in exacerbating amyloid and tau pathology as well as synaptic degeneration.

A machine learning strategy to mitigate the inappropriateness of procalcitonin request in clinical practice.

Aim: The aim of this study was to develop machine learning (ML) models to mitigate the inappropriate request of Procalcitonin (PCT) in clinical wards. Material and methods: We built six different ML models based on both demographical data, i.e., sex and age, and laboratory parameters, i.e., cell blood count (CBC) parameters, inclusive of monocyte distribution width (MDW), and C-reactive protein (CRP). The dataset included 1667 PCT measurements of different patients. Based on a PCT cut-off of 0.50 ng/mL, we found 1090 negative (65.4%) and 577 positive (34.6%) results. We performed a 70:15:15 train:validation:test splitting based on the outcome. Results: Random Forest, Support Vector Machine and eXtreme Gradient Boosting showed optimal performances for predicting PCT positivity, with an area under the curve ranging from 0.88 to 0.89. Conclusions: The ML models developed could represent a useful tool to predict PCT positivity, avoiding unusefulness PCT requests. ML models are based on laboratory tests commonly ordered together with PCT but have the great advantage to be easy to measure and low-cost.