Cerebrospinal fluid and plasma concentrations of the inflammatory marker soluble CD27 in a large surgical population.

Soluble CD27 (sCD27) is a potential biomarker for diseases involving immune dysfunction. As there is currently little data on cerebrospinal fluid (CSF) sCD27 concentrations in the general population we measured CSF and plasma concentrations in 486 patients (age range 18-92 years, 57% male) undergoing spinal anesthesia for elective surgery. Across the complete cohort the median [range] sCD27 concentrations were 163 [<50 to 7474] pg/mL in CSF and 4624 [1830 to >400,000] pg/mL in plasma. Plasma sCD27, age and Qalb were the factors most strongly associated with CSF sCD27 levels. Reference sCD27 concentration intervals (central 95% of values) in a sub-group without the indication of neuropsychiatric, inflammatory or systemic disease (158 patients) were <50 pg/mL - 419 pg/mL for CSF and 2344-36422 pg/mL for plasma. These data provide preliminary reference ranges that could inform future studies of the validity of sCD27 as a biomarker for neuro- and systemic inflammatory disorders.

Child and Parent Risk and Resilience Factors as Predictors of Long-term Recovery in Youth Undergoing Spinal Fusion Surgery.

OBJECTIVES: Undertreated pediatric postsurgical pain negatively affects health-related quality of life (HRQOL) and functioning and may lead to chronic postsurgical pain (CPSP). Predictors of recovery have been identified but more research is needed, particularly regarding resilience, social factors, and long-term effects. The aim of the present study was to investigate child and parent risk and resilience factors as predictors of long-term postsurgical recovery for adolescents. METHODS: Participants were patients with Adolescent Idiopathic Scoliosis (AIS), 12 to 18 years old, undergoing spinal fusion, and their parents. Recruitment occurred at the orthopedic units at 4 hospitals in Belgium. Data were collected before surgery (T0), at 3 (T1) and 6 weeks (T2), 6 months (T3), and 1 year (T4) post surgery. Multiple regression models were used to evaluate the predictive effect of pain intensity, pain catastrophizing, psychological flexibility, and pain acceptance on long-term functioning, HRQOL, and pain. RESULTS: The sample comprised 100 adolescents and 61 parents. Pain at T0, T1, and T3 and adolescent pain catastrophizing (T0) predicted health-related quality of life, functioning, and pain at T4 (while pain at T2 predicted HRQOL and pain). Parent pain catastrophizing predicted pain at T4. Adolescent and parental psychological flexibility predicted HRQOL, and parent psychological flexibility also predicted pain at T4. Adolescent acceptance at T1 predicted pain, and acceptance at T2 predicted HRQOL, at T4. DISCUSSION: The study identified pain and adolescent pain catastrophizing as risk factors, and adolescent and parental psychological flexibility and adolescent pain acceptance as resilience factors, for long-term recovery in youths undergoing spinal fusion. Postsurgical pain management targeting these factors may therefore promote recovery for these adolescents.

Increased plasma endostatin and GDF15 in indolent non-Hodgkin lymphoma.

Background: Increased microvascular density correlates with more advanced disease and unfavorable overall survival in non-Hodgkin lymphoma (NHL), suggesting that angiogenesis is important for disease progression. However, studies of anti-angiogenic agents in NHL patients, have generally not shown favorable outcomes. The aim of this study was to investigate whether plasma levels of a subset of angiogenesis-associated proteins are increased in indolent B-cell derived NHL (B-NHL) and to investigate whether the levels differ between patients with asymptomatic versus symptomatic disease. Methods: Plasma levels of growth differentiation factor 15 (GDF15), endostatin, matrix metalloproteinase 9 (MMP9), neutrophil gelatinase-associated lipocalin (NGAL), long pentraxin 3 (PTX3), and galectin 3 (GAL-3) were measured by ELISA in 35 patients with symptomatic indolent B-NHL, 41 patients with asymptomatic disease, and 62 healthy controls. Bootstrap t-tests were used to assess the relative differences in biomarker levels between groups. Group differences were visualized using a principal component plot. Results: Mean plasma endostatin and GDF15 levels were significantly higher in symptomatic and asymptomatic lymphoma patients than in controls. Symptomatic patients had higher mean MMP9 and NGAL than controls. Conclusions: The finding of increased plasma endostatin and GDF15 in patients with asymptomatic indolent B-NHL suggests that increased angiogenic activity is an early event in indolent B-NHL disease progression.

Increased levels of a subset of angiogenesis-related plasma proteins in essential thrombocythemia.

Background: Increased local angiogenesis is important for the growth and dissemination of cancer. The myeloproliferative neoplasm essential thrombocythemia (ET) is known to involve increased bone marrow angiogenesis. Blood levels of several angiogenesis-related proteins are increased in different types of cancer. The aim of this study was to investigate whether a subset of such proteins was elevated in treatment-naïve ET patients. Methods: Blood plasma from 41 ET patients and 43 healthy aged-matched controls was analyzed for eight different angiogenesis-related proteins. Results: The ET cohort displayed a more homogenous expression pattern of these proteins compared with controls. Five of the eight proteins were significantly increased in ET patients. Conclusion: Increased plasma levels of matrix metallopeptidase 9 (MMP9) and endostatin have not previously been reported in ET. In our patients, MMP9 levels correlated positively with Janus kinase 2 (JAK2) V617F allele burden and leukocyte count.

Increased Plasma GDF15 Is Associated with Altered Levels of Soluble VEGF Receptors 1 and 2 in Symptomatic Multiple Myeloma.

INTRODUCTION: In multiple myeloma, there is an increase in bone marrow microvascular density and enhanced renal lymphangiogenesis. Increased levels of the proangiogenic protein growth differentiation factor-15 (GDF15) have previously been reported to be associated with poor prognosis in myeloma. A possible association between GDF15 and the soluble forms of vascular endothelial growth factor receptors (sVEGFR) 1 and 2 has not yet been investigated, and a role for these receptors in pathological angiogenesis in myeloma is still to be defined. METHODS: Plasma levels of GDF15 and sVEGFR1 and 2 were determined by ELISA in patients with smouldering multiple myeloma (sMM), patients with symptomatic multiple myeloma (abbreviated as MM), and healthy controls. The levels were compared between the three groups, and correlation coefficients were calculated, as were Kaplan-Meier curves for GDF15 and sVEGFR1 and sVEGFR2. RESULTS: Levels of GDF15 were significantly higher in MM than in both patients with sMM and controls. A gradual decrease in mean sVEGFR1 concentration was observed, with MM > sMM > controls. Mean sVEGFR2 was lower in patients with MM than in controls. There was a positive correlation between GDF15 and sVEGFR1, and GDF15 correlated negatively with sVEGFR2. High GDF15 (>3 ng/mL) was associated with poor prognosis. CONCLUSION: In multiple myeloma, increased expression of GDF15 correlates positively with sVEGFR1 and negatively with sVEGFR2. It is possible that the altered levels of sVEGFR1 and 2 contribute to the increased angio- and lymphangiogenesis observed in myeloma.

Follow-up after infectious mononucleosis in search of serological similarities with presymptomatic multiple sclerosis.

BACKGROUND: A two- to three-fold increase in the risk of multiple sclerosis (MS) after infectious mononucleosis (IM) has been observed in cohort and case control studies. However, this association has not been investigated prospectively from IM. It remains to be determined whether long-term immunospecific sequelae with features consistent with presymptomatic MS occur after IM. METHODS: Sera were obtained from individuals with acute IM from 2003-2007 (n = 42) and from the same individuals at a follow-up (FU) study approximately 10 years after IM. These were assayed for antibodies against a variety of Epstein-Barr virus (EBV) antigens, including gp350, a novel recombinant glycoprotein from the EBV envelope. Similarly, single-protein antigens were used to assess measles and varicella-zoster reactivity (Ncore and varicella-zoster glycoprotein E [VZVgE]). The FU study also included cerebrospinal fluid (CSF) samples from 21 of these individuals to test for IgG antibodies against the same viral antigens. As controls, CSF and serum samples were obtained from 15 EBV-seropositive volunteers who denied a history of IM, and serum samples were obtained from 24 EBV-seropositive blood donors. Anti-gp350, anti-Ncore and anti-VZVgE IgG levels were also analysed in sera and CSF samples from 22 persons with MS. RESULTS: The FU assays showed higher anti-gp350 IgG (p = 0.007, univariate) than among healthy controls, with no difference in serum anti-VCA or anti-EBNA1 IgG levels and no difference in anti-gp350 in the CSF samples. Anti-Ncore IgG and anti-VZVgE were higher in acute IM samples (p < 0.001 and p < 0.0001, respectively) than at FU, although anti-Ncore remained heightened in an age-adjusted analysis at FU (p = 0.014) compared to the control group. In the MS group, the serum anti-gp350 and anti-Ncore IgG levels were significantly higher than among the control group, but the anti-VZVgE levels were not. The CSF anti-gp350 and VZVgE levels were slightly higher among persons with MS than among the control group, whereas anti-Ncore IgG was markedly higher in persons with MS than in the control group. CONCLUSION: In the present study IM showed certain similarities with MS. Increased anti-gp350 reactivity persisted more than a decade after IM, reminiscent of the established increased anti-EBV reactivity in presymptomatic MS. Acute IM was associated with increased anti-measles and anti-VZV immunoreactivity, similar to the MRZ reaction in MS, with some evidence suggesting that this measles reactivity persisted after a decade.

Strong Associations Between Early Tubular Damage and Urinary Cytokine, Chemokine, and Growth Factor Levels in Elderly Males and Females.

Acute tubular necrosis is associated with high mortality rates and it is important to develop new biomarkers for tubular damage. The aim of this study was to investigate the effect of early tubular damage on a large number of urinary cytokines, chemokines, and growth factors. We selected 90 urine samples from the Prospective Investigation of the Vasculature in Uppsala Seniors Study (41 males and 49 females). The tubular damage markers cystatin C, neutrophil gelatinase-associated lipocalin (NGAL), and kidney injury molecule-1 (KIM-1) were analyzed in the urine samples and urinary cytokine levels were analyzed with 2 multiplex assays (proximity extension assay). After adjustment for sex, body mass index, estimated glomerular filtration rate, smoking, and multiplicity testing using the false discovery rate approach, there remained 26 cytokines that correlated significantly with urine cystatin C, 27 cytokines that correlated with NGAL, and 66 cytokines that correlated with KIM-1. Tubular damage shows a strong association with urinary cytokines, chemokines, and growth factors. Our findings indicate that multiplex proteomics could be a promising new approach to explore the complex effects of tubular damage.

Albumin Urinary Excretion Is Associated with Increased Levels of Urinary Chemokines, Cytokines, and Growth Factors Levels in Humans.

The aim of the present study was to study the associations between urine albumin excretion, and a large number of urinary chemokines, cytokines, and growth factors in a normal population. We selected 90 urine samples from individuals without CVD, diabetes, stroke or kidney disease belonging to the Prospective Investigation of the Vasculature in Uppsala Seniors Study (41 males and 49 females, all aged 75 years). Urinary cytokine levels were analyzed with two multiplex assays (proximity extension assays) and the cytokine levels were correlated with urine albumin. After adjustment for sex, body mass index (BMI), estimated glomerular filtration rate (eGFR), smoking and multiplicity testing, 11 biomarkers remained significantly associated with urine albumin: thrombospondin 2, interleukin 6, interleukin 8, hepatocyte growth factor, matrix metalloproteinase-12 (MMP-12), C-X-C motif chemokine 9, tumor necrosis factor receptor superfamily member 11B, osteoprotegerin, growth-regulated alpha protein, C-X-C motif chemokine 6, oncostatin-M (OSM) and fatty acid-binding protein, intestinal, despite large differences in molecular weights. In this study, we found associations between urinary albumin and both small and large urine proteins. Additional studies are warranted to identify cytokine patterns and potential progression markers in various renal diseases.

Intrathecal immunoreactivity in people with or without previous infectious mononucleosis.

OBJECTIVES: The risk of developing multiple sclerosis (MS) increases (OR: 3.1) after infectious mononucleosis (IM). However, the nature of this link is obscure. We tested the hypothesis that IM might incur long-term sequelae, including low-key inflammatory activity, with characteristics of an MS endophenotype (or presymptomatic trait) and that assays of MS-relevant cyto-/chemokines in the cerebrospinal fluid (CSF) post-IM may show a trend in this direction. MATERIALS AND METHODS: We selected seven CSF cytokines (IL-1b, IL-6, YKL-40, TNF-alpha) or chemokines (IL-8, CCL2, IP-10), representing pro-inflammatory factors previously associated with MS. We assayed the CSF levels of these seven cyto-/chemokines in healthy individuals with a median follow-up time of 10 years after serologically confirmed IM (post-IM group, n = 22), and in healthy controls without a history of IM (n = 19). A group of MS patients (n = 23) were included as reference. RESULTS: The CSF levels of IP-10, YKL-40, and CCL-2 were higher in the post-IM group than in our IM unexposed controls (P = .021, .049, .028). Seven of seven cyto-/chemokine assays showed a trend in the predicted direction (P of binomial ratio = .008). However, this trend was non-significant in a multivariate test (P = .22). A power analysis indicated that similar studies including a larger cohort would be numerically realistic. CONCLUSIONS: These results do not reject the hypothesis that the established epidemiological association between IM and MS results from a stepwise inflammatory propagation from IM sequelae to an MS endophenotype (or presymptomatic trait) in a proportion of IM patients, pending confirmation with adequate power.

Increased levels of the cardiovascular disease risk biomarkers GDF15 and myostatin in patients with chronic lymphocytic leukemia.

Individuals suffering from cancer, including hematological malignancies, are at increased risk of cardiovascular disease (CVD). Elevated levels of several biomarkers in blood are associated with an increased risk of CVD. The aim of this study was to investigate whether a subset of such CVD risk biomarkers was elevated in patients with untreated chronic lymphocytic leukemia (CLL). Blood plasma and serum from 139 CLL patients and 71 healthy age-matched controls were analyzed for 11 proposed CVD risk biomarkers. The CLL cohort displayed a more heterogeneous pattern of biomarker expression compared to controls. The majority, eight out of 11, analyzed CVD risk biomarkers differed significantly in concentrations between CLL patients and controls. Increased levels of the biomarkers GDF15 and myostatin have not previously been reported in CLL. Further prospective studies are warranted to investigate whether these biomarkers predict future cardiovascular events in patients with CLL.

Profiling surface proteins on individual exosomes using a proximity barcoding assay.

Exosomes have been implicated in numerous biological processes, and they may serve as important disease markers. Surface proteins on exosomes carry information about their tissues of origin. Because of the heterogeneity of exosomes it is desirable to investigate them individually, but this has so far remained impractical. Here, we demonstrate a proximity-dependent barcoding assay to profile surface proteins of individual exosomes using antibody-DNA conjugates and next-generation sequencing. We first validate the method using artificial streptavidin-oligonucleotide complexes, followed by analysis of the variable composition of surface proteins on individual exosomes, derived from human body fluids or cell culture media. Exosomes from different sources are characterized by the presence of specific combinations of surface proteins and their abundance, allowing exosomes to be separately quantified in mixed samples to serve as markers for tissue-specific engagement in disease.

High levels of cerebrospinal fluid chemokines point to the presence of neuroinflammation in peripheral neuropathic pain: a cross-sectional study of 2 cohorts of patients compared with healthy controls.

Animal models suggest that chemokines are important mediators in the pathophysiology of neuropathic pain. Indeed, these substances have been called "gliotransmitters," a term that illustrates the close interplay between glial cells and neurons in the context of neuroinflammation and pain. However, evidence in humans is scarce. The aim of the study was to determine a comprehensive cerebrospinal fluid (CSF) inflammatory profile of patients with neuropathic pain. Our hypothesis was that we would thereby find indications of a postulated on-going process of central neuroinflammation. Samples of CSF were collected from 2 cohorts of patients with neuropathic pain (n = 11 and n = 16, respectively) and healthy control subjects (n = 11). The samples were analyzed with a multiplex proximity extension assay in which 92 inflammation-related proteins were measured simultaneously (Proseek Multiplex Inflammation I; Olink Bioscience, Uppsala, Sweden). Univariate testing with control of false discovery rate, as well as orthogonal partial least squares discriminant analysis, were used for statistical analyses. Levels of chemokines CXCL6, CXCL10, CCL8, CCL11, CCL23 in CSF, as well as protein LAPTGF-beta-1, were significantly higher in both neuropathic pain cohorts compared with healthy controls, pointing to neuroinflammation in patients. These 6 proteins were also major results in a recent similar study in patients with fibromyalgia. The findings need to be confirmed in larger cohorts, and the question of causality remains to be settled. Because it has been suggested that prevalent comorbidities to chronic pain (eg, depression, anxiety, poor sleep, and tiredness) also are associated with neuroinflammation, it will be important to determine whether neuroinflammation is a common mediator.

Reversion of High-level Mecillinam Resistance to Susceptibility in Escherichia coli During Growth in Urine.

Mecillinam (amdinocillin) is a ß-lactam antibiotic used to treat uncomplicated urinary tract infections (UTIs). We have previously shown that inactivation of the Escherichia coli cysB gene is the major cause of mecillinam resistance (MecR) in clinical isolates. In this study, we used different E. coli strains (laboratory and clinical isolates) that were MecR due to cysB mutations to determine how mecillinam susceptibility was affected during growth in urine compared to growth in the commonly used growth medium Mueller Hinton (MHB). We also examined mecillinam susceptibility when bacteria were grown in urine obtained from 48 different healthy volunteers. Metabolome analysis was done on the urine samples and the association between the mecillinam susceptibility patterns of the bacteria and urine metabolite levels was studied. Two major findings with clinical significance are reported. First, MecRE. coli cysB mutant strains (both laboratory and clinical isolates) were always more susceptible to mecillinam when grown in urine as compared to laboratory medium, with many strains showing complete phenotypic susceptibility in urine. Second, the degree of reversion to susceptibility varied between urine samples obtained from different individuals. This difference was correlated with osmolality such that in urine with low osmolality the MecR mutants were more susceptible to mecillinam than in urine with high osmolality. This is the first example describing conditional resistance where a genetically stable antibiotic resistance can be phenotypically reverted to susceptibility by metabolites present in urine. These findings have several important clinical implications regarding the use of mecillinam to treat UTIs. First, they suggest that mecillinam can be used to treat also those clinical strains that are identified as MecR in standard laboratory tests. Second, the results suggest that testing of mecillinam susceptibility in the laboratory ought to be performed in media that mimics urine to obtain clinically relevant susceptibility testing results. Third, these findings imply that changes in patient behavior, such as increased water intake or use of diuretics to reduce urine osmolality and increased intake of cysteine, might induce antibiotic susceptibility in an infecting MecRE. coli strain and thereby increase treatment efficiency.