Definition of an Inflammatory Biomarker Signature in Plasma-Derived Extracellular Vesicles of Glioblastoma Patients

Glioblastoma (GB) is an aggressive type of tumour for which therapeutic options and biomarkers are limited. GB diagnosis mostly relies on symptomatic presentation of the tumour and, in turn, brain imaging and invasive biopsy that can delay its diagnosis. Description of easily accessible and effective biomarkers present in biofluids would thus prove invaluable in GB diagnosis. Extracellular vesicles (EVs) derived from both GB and stromal cells are essential to intercellular crosstalk in the tumour bulk, and circulating EVs have been described as a potential reservoir of GB biomarkers. Therefore, EV-based liquid biopsies have been suggested as a promising tool for GB diagnosis and follow up. To identify GB specific proteins, sEVs were isolated from plasma samples of GB patients as well as healthy volunteers using differential ultracentrifugation, and their content was characterised through mass spectrometry. Our data indicate the presence of an inflammatory biomarker signature comprising members of the complement and regulators of inflammation and coagulation including VWF, FCGBP, C3, PROS1, and SERPINA1. Overall, this study is a step forward in the development of a non-invasive liquid biopsy approach for the identification of valuable biomarkers that could significantly improve GB diagnosis and, consequently, patients’ prognosis and quality of life.

COVID-19 severity and in-hospital mortality in an area with high HIV prevalence

Background: HIV is moderate risk factor for developing severe COVID-19 and is associated with increased risk of COVID-19 mortality. HIV infection causes immune dysregulation characterised by progressive lymphopenia, chronic immune activation, immunological senescence, and T cell exhaustion. These changes are partly reversed by effective antiretroviral therapy (ART), which reduces morbidity and mortality in people living with HIV (PWH). We investigated the associations among clinical phenotypes, laboratory biomarkers, and hospitalisation outcomes in a cohort of people hospitalised with COVID-19 in a high HIV prevalence area.Methods: We conducted a prospective observational cohort study in the Tshwane District Hospital complex in Pretoria, South Africa. We analysed data for patients admitted from April to November 2020, before the SARS-CoV-2 Beta variant-driven second wave. Respiratory disease severity was quantified using the respiratory oxygenation (ROX) score. Analysed biomarkers included full blood counts, differential white cell counts, C-reactive protein (CRP), ferritin, procalcitonin (PCT), D-dimer (DDIM), creatinine, alanine aminotransferase (ALT), CD4 T cell counts, and HIV-1 viral loads (HIVVL).Results: The analysis included 558 patients, of whom 112 (21.7%) died during admission. The mean age of the cohort was 54 (SD ±16) years, and numbers of males (50.5%) and females (49.5%) were equivalent. A total of 82 (15%) were HIV-positive. PWH were younger (mean age 46 years) than HIV-negative people; most were on ART with a suppressed HIVVL (72%) and the median CD4 count was 159 (IQR 66-397) cells/µL at the time of admission. After adjusting for age, HIV was not associated with significantly increased risk of mortality during hospitalisation (aHR=1.1, 95% CI: 0.6-2.0). Levels of supportive care were similar in HIV-negative patients and PWH. Inflammatory biomarker levels were equivalent in PWH and HIV-negative patients. A total of 15 PWH had detectable HIVVLs (>1000 copies/mL). Detectable HIVVL was associated with higher ROX scores - indicating less severe respiratory disease. In PWH, mortality was associated with higher levels of CRP, ferritin, PCT and DDIM. When compared to HIV-negative patients who died, PWH who died were younger, had higher DDIM levels, and were more likely to have tuberculosis.Conclusions: HIV per se was not associated with substantively increased risk of severe disease, or in-hospital mortality from COVID-19. Respiratory disease was less severe in PWH with detectable HIVVL. Inflammatory biomarker levels were equivalent in PWH and HIV-negative people, regardless of HIVVL. Increased levels of inflammatory biomarkers and DDIM were associated with in-hospital mortality irrespective of HIV status.

Chitinase-3-like Protein 1 (YKL-40): A New Biomarker of Inflamma­tion in Pyoderma Gangrenosum

Pyoderma gangrenosum (PG) is a rare, neutrophil­ic dermatosis with unclear aetiopathology, considered as an autoinflammatory disease, associated with other immune-mediated disorders. Chitinase-3-like protein 1 (YKL-40) is an inflammatory biomarker secreted by a wide variety of cells, including neutrophils. To evaluate YKL-40 serum level in relation to clinicopathological data, 48 patients with PG and 40 healthy controls were enrolled in the study. Skin lesions were measured to calculate the affected area. Inflammatory parameters (C-reactive protein, white blood cell count with neutrophils) were determined from blood samples. YKL-40 and IL-6 levels were measured in serum by enzyme-linked immunosorbent assay. YKL-40 serum level was significantly higher in patients with PG than in controls (58.4 vs 36.4 ng/ml, respectively; p < 0.00001). The positive correlation between YKL-40 level and IL-6 level was observed (r=0.48, p = 0.0006) along with a trend towards significance of relationship between YKL-40 level and C-reactive protein (r=0.28, p = 0.052). YKL-40 can be considered a valuable biomarker of inflammation in PG.

Molecular and clinical signatures in Acute Kidney Injury define distinct subphenotypes that associate with death, kidney, and cardiovascular events

Introduction: AKI is a heterogeneous syndrome defined via serum creatinine and urine output criteria. However, these markers are insufficient to capture the biological complexity of AKI and not necessarily inform on future risk of kidney and clinical events. Methods: Data from ASSESS-AKI was obtained and analyzed to uncover different clinical and biological signatures within AKI. We utilized a set of unsupervised machine learning algorithms incorporating a comprehensive panel of systemic and organ-specific biomarkers of inflammation, injury, and repair/health integrated into electronic data. Furthermore, the association of these novel biomarker-enriched subphenotypes with kidney and cardiovascular events and death was determined. Clinical and biomarker concentration differences among subphenotypes were evaluated via classic statistics. Kaplan-Meier and cumulative incidence curves were obtained to evaluate longitudinal outcomes. Results: Among 1538 patients from ASSESS-AKI, we included 748 AKI patients in the analysis. The median follow-up time was 4.8 years. We discovered 4 subphenotypes via unsupervised learning. Patients with AKI subphenotype 1 (injury cluster) were older (mean age +/- SD): 71.2 +/- 9.4 (p<0.001), with high ICU admission rates (93.9%, p<0.001) and highly prevalent cardiovascular disease (71.8%, p<0.001). They were characterized by the highest levels of KIM-1, troponin T, and ST2 compared to other clusters (P<0.001). AKI subphenotype 2 (benign cluster) is comprised of relatively young individuals with the lowest prevalence of comorbidities and highest levels of systemic anti-inflammatory makers (IL-13). AKI Subphenotype 3 (chronic inflammation and low injury) comprised patients with markedly high pro-BNP, TNFR1, and TNFR2 concentrations while presenting low concentrations of KIM-1 and NGAL. Patients with AKI subphenotype 4 (inflammation-injury) were predominantly critically ill individuals with the highest prevalence of sepsis and stage 3 AKI. They had the highest systemic (IL-1B, CRP, IL-8) and kidney inflammatory biomarker activity (YKL-40, MCP-1) as well as high kidney injury levels (NGAL, KIM-1). AKI subphenotype 3 and 4 were independently associated with a higher risk of death compared to subphenotype 2. Moreover, subphenotype 3 was independently associated with CKD outcomes and CVD events. Conclusion: We discovered four clinically meaningful AKI subphenotypes with statistical differences in biomarker composites that associate with longitudinal risks of adverse clinical events. Our approach is a novel look at the potential mechanisms underlying AKI and the putative role of biomarkers investigation.

C-reactive protein as a diagnostic marker of neonatal sepsis in association with blood culture a retrospective study at a tertiary care hospital

To evaluate the sensitivity and specificity of C-Reactive protein as a single diagnostic inflammatory biomarker of neonatal sepsis in association with the blood culture.In this study, we retrospectively reviewed the medical records of 330 neonates at a tertiary care hospital at Gurugram from Jan, 2015 to Dec, 2020. The study population included neonates &#60;1month age. Neonates meeting the IPSC criteria (Sepsis 2.0)1 and with a positive culture were considered as neonates with proven sepsis. Neonates with congenital malformations and congenital infections associated with TORCH complex were excluded from the study.Of the 330 neonates screened for sepsis, 32 (10%) had a positive blood culture with raised CRP in 69 (21%) cases. Among the 32 cases with positive blood culture, CRP identified 29 cases. The sensitivity, specificity, positive predictive value, negative predictive values of CRP were 90.6%, 86.5%, 42% and 99% respectively. The area under the curve (AUC) for the CRP ROC analysis was 0.83 with sensitivity of 90.6% and specificity of 91.6% which showed CRP usefulness as the diagnostic inflammatory biomarker of neonatal sepsis.Prematurity (53%) in neonates was the most common risk factor associated with neonatal sepsis. Klebsiella pneumoniae 11 (34%) was the most common pathogen isolated with 73% susceptibility to Ciprofloxacin.C-Reactive protein was found to have a high diagnostic value in terms of sensitivity of 90.6% and specificity of 91.6% when 0.83 is used as a cut off point for diagnosis of neonatal sepsis. Therefore, CRP could be used as diagnostic inflammatory biomarker in resource poor settings.

INTERLEUKIN AS BIOMARKER OF RECURRENT APHTHOUS STOMATITIS (RAS): A SYSTEMATIC LITERATURE REVIEW

This review aimed to describe the interleukins and interleukin gene polymorphisms related to and recommended as a RAS biomarker. Articles were searched through PubMed, ScienceDirect, and Cochrane Library databases, using the keywords of “Interleukin” AND “Recurrent Aphthous Stomatitis”. The Risk of Bias Assessment tool for Non-randomized Studies (RoBANS) was used, and the writing of this review refers to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. A total of 8 articles met the criteria and showed a low risk of bias assessment. The level of IL-2, IL-6, IL-8, and IL-18 in the acute clinical phase of RAS were higher than in the recovery phase, but IL-10 levels showed decreased. IL-2, IL-6, IL-10 gene polymorphisms were found to be more frequent in RAS patients compared to controls, while IL-12 gene polymorphisms were found to be less associated with RAS pathogenesis. Interleukins at the proteomic level that recommended as a pro-inflammatory biomarker are IL-2, IL-6, IL-8, IL-12, and IL-18, while an anti-inflammatory is IL-10. Only IL-2 can be recommended as a biomarker at the genomic level, as other interleukins still require more investigation.

COVID-19 severity and in-hospital mortality in an area with high HIV prevalence

Background: HIV is moderate risk factor for developing severe COVID-19 and is associated with increased risk of COVID-19 mortality. HIV infection causes immune dysregulation characterised by progressive lymphopenia, chronic immune activation, immunological senescence, and T cell exhaustion. These changes are partly reversed by effective antiretroviral therapy (ART), which reduces morbidity and mortality in people living with HIV (PWH). We investigated the associations among clinical phenotypes, laboratory biomarkers, and hospitalisation outcomes in a cohort of people hospitalised with COVID-19 in a high HIV prevalence area.Methods: We conducted a prospective observational cohort study in the Tshwane District Hospital complex in Pretoria, South Africa. We analysed data for patients admitted from April to November 2020, before the SARS-CoV-2 Beta variant-driven second wave. Respiratory disease severity was quantified using the respiratory oxygenation (ROX) score. Analysed biomarkers included full blood counts, differential white cell counts, C-reactive protein (CRP), ferritin, procalcitonin (PCT), D-dimer (DDIM), creatinine, alanine aminotransferase (ALT), CD4 T cell counts, and HIV-1 viral loads (HIVVL).Results: The analysis included 558 patients, of whom 112 (21.7%) died during admission. The mean age of the cohort was 54 (SD ±16) years, and numbers of males (50.5%) and females (49.5%) were equivalent. A total of 82 (15%) were HIV-positive. PWH were younger (mean age 46 years) than HIV-negative people; most were on ART with a suppressed HIVVL (72%) and the median CD4 count was 159 (IQR 66-397) cells/µL at the time of admission. After adjusting for age, HIV was not associated with significantly increased risk of mortality during hospitalisation (aHR=1.1, 95% CI: 0.6-2.0). Levels of supportive care were similar in HIV-negative patients and PWH. Inflammatory biomarker levels were equivalent in PWH and HIV-negative patients. A total of 15 PWH had detectable HIVVLs (>1000 copies/mL). Detectable HIVVL was associated with higher ROX scores - indicating less severe respiratory disease. In PWH, mortality was associated with higher levels of CRP, ferritin, PCT and DDIM. When compared to HIV-negative patients who died, PWH who died were younger, had higher DDIM levels, and were more likely to have tuberculosis.Conclusions: HIV per se was not associated with substantively increased risk of severe disease, or in-hospital mortality from COVID-19. Respiratory disease was less severe in PWH with detectable HIVVL. Inflammatory biomarker levels were equivalent in PWH and HIV-negative people, regardless of HIVVL. Increased levels of inflammatory biomarkers and DDIM were associated with in-hospital mortality irrespective of HIV status.

Mitochondrial control of microglial phagocytosis in Alzheimer’s disease

Microglial phagocytosis is an energetically demanding process that plays a critical role in the removal of toxic aggregates of beta amyloid (Aβ) in Alzheimer’s disease (AD). Recent evidence indicates that metabolic programming may breakdown in microglia in AD, thereby disrupting this important protective function. The mechanisms coordinating mitochondrial metabolism to fuel phagocytosis in microglia remain poorly understood, however. Here we demonstrate that mitochondrial displacement of the glucose metabolizing enzyme, hexokinase-II (HK) regulates microglial metabolism and phagocytosis, and that deletion of the translocator protein (TSPO) inhibits this. TSPO is a PET-visible inflammatory biomarker and therapeutic target in AD, previously shown to regulate microglial metabolism via an unknown mechanism. Using RNAseq and proteomic analyses, we found TSPO function in the brain to be linked with the regulation of mitochondrial bioenergetics, lipid metabolism and phagocytosis. In cultured microglia, TSPO deletion was associated with elevated mitochondrial recruitment of HK, which was associated with a switch to non-oxidative glucose metabolism, reduced mitochondrial energy production, lipid storage and impaired phagocytosis. Consistent with in vitro findings, TSPO expression was also associated with phagocytic microglia in both AD brain and AD mice. Conversely, TSPO deletion in AD mice reduced phagocytic microglia and exacerbated amyloid accumulation. Based on these findings we propose that microglial TSPO functions as an immunometabolic brake via regulation of mitochondrial HK recruitment, preventing hyperglycolysis and promoting phagocytosis in AD. Further, we demonstrate that targeting mitochondrial HK may offer a novel immunotherapeutic approach to promote microglial phagocytosis in AD.