Bilateral Renal Hypoplasia with High β2-Microglobulinuria in the Neonatal Period

Urinary β2 microglobulin (β2-MG) is a low-molecular-weight protein that is filtered by the glomerular basement membrane and absorbed by the proximal tubule epithelial cells. In perinatal management, urinary β2-MG levels are used to assess intrauterine inflammation in newborns, since urinary excretion increases during inflammation. Furthermore, β2-MG levels in fetal blood and urine are also used for predicting fetal renal function because β2-MG is not transferred to the placenta. Herein, we reported a patient with persistent high urinary β2-MG levels since neonatal period, who was later diagnosed with bilateral renal hypoplasia. If a newborn presents persistent hyper β2-microglobulinuria even without hematuria or proteinuria, congenital renal malformations should be considered.

Development of a protein assay with copper chelator chromeazurol B, based on the biuret reaction

This study aimed to provide a novel and highly sensitive protein assay based on the biuret reaction and using chromeazurol B, a metal chelate compound. The method consists of two reagents and an automated analyzer. First, a complex of copper and protein (biuret reaction) is formed. Second, a chelating reagent containing chromeazurol B forms a three-dimensional complex of protein, copper, and chromeazurol B at neutral pH, resulting in highly sensitive coloration. The intra-assay (n = 20) variation for the three levels was 3.54 % or lower at each concentration. Each response with α, β-, and γ-globulin was 103.8 % and 104.3 %, respectively, against albumin. The molar absorption coefficient (ε) of the present method was 2.5 × 10⁵ m²/mol against human albumin, higher than that of the commercially available Lowry method (ε = 8.7 × 10⁴ m²/mol), which is based on the same principle. The correlation test for the pyrogallol method with 30 urine samples showed good performance (r = 0.961). The method described here (the Biuret-based CAB method) is a more sensitive and rapid assay than the Lowry method, and it may also be applied to biological samples because of its similar reactivity towards various proteins.

Investigation of D76N β2-Microglobulin Using Protein Footprinting and Structural Mass Spectrometry

NMR studies and X-ray crystallography have shown that the structures of the 99-residue amyloidogenic protein β₂-microglobulin (β₂m) and its more aggregation-prone variant, D76N, are indistinguishable, and hence, the reason for the striking difference in their aggregation propensities remains elusive. Here, we have employed two protein footprinting methods, hydrogen-deuterium exchange (HDX) and fast photochemical oxidation of proteins (FPOP), in conjunction with ion mobility-mass spectrometry, to probe the differences in conformational dynamics of the two proteins. Using HDX-MS, a clear difference in HDX protection is observed between these two proteins in the E-F loop (residues 70-77) which contains the D76N substitution, with a significantly higher deuterium uptake being observed in the variant protein. Conversely, following FPOP-MS only minimal differences in the level of oxidation between the two proteins are observed in the E-F loop region, suggesting only modest side-chain movements in that area. Together the HDX-MS and FPOP-MS data suggest that a tangible perturbation to the hydrogen-bonding network in the E-F loop has taken place in the D76N variant and furthermore illustrate the benefit of using multiple complementary footprinting methods to address subtle, but possibly biologically important, differences between highly similar proteins.

Biomarker Discovery in Patients with Immunotherapy-Treated Melanoma with Imaging Mass Cytometry

PURPOSE

Imaging mass cytometry (IMC) is among the first tools with the capacity for multiplex analysis of more than 40 targets, which provides a novel approach to biomarker discovery. Here, we used IMC to characterize the tumor microenvironment of patients with metastatic melanoma who received immunotherapy in efforts to find indicative factors of treatment response. In spite of the new power of IMC, the image analysis aspects are still limited by the challenges of cell segmentation.

EXPERIMENTAL DESIGN

Here, rather than segment, we performed image analysis using a newly designed version of the AQUA software to measure marker intensity in molecularly defined compartments: tumor cells, stroma, T cells, B cells, and macrophages. IMC data were compared with quantitative immunofluorescence (QIF) and digital spatial profiling.

RESULTS

Validation of IMC results for immune markers was confirmed by regression with additional multiplexing methods and outcome assessment. Multivariable analyses by each compartment revealed significant associations of 12 markers for progression-free survival and seven markers for overall survival (OS). The most compelling indicative biomarker, beta2-microglobulin (B2M), was confirmed by correlation with OS by QIF in the discovery cohort and validated in an independent published cohort profiled by mRNA expression.

CONCLUSIONS

Using digital image analysis based on pixel colocalization to assess IMC data allowed us to quantitively measure 25 markers simultaneously on formalin-fixed, paraffin-embedded tissue microarray samples. In addition to showing high concordance with other multiplexing technologies, we identified a series of potentially indicative biomarkers for immunotherapy in metastatic melanoma, including B2M.

Multiplexed MRM-Based Proteomics Identified Multiple Biomarkers of Disease Severity in Human Heart Failure

Heart failure (HF) is a complex disease due to the intricate interplay of several mechanisms, which therefore implies the need for a multimarker strategy to better personalize the care of patients with HF. In this study, we developed a targeted mass spectrometry approach based on multiple reaction monitoring (MRM) to measure multiple circulating protein biomarkers, involved in cardiovascular disease, to address their relevance in the human HF, intending to assess the feasibility of the workflow in the disease monitoring and risk stratification. In this study, we analyzed a total of 60 plasma proteins in 30 plasma samples from eight control subjects and 22 age- and gender- matched HF patients. We identified a panel of four plasma proteins, namely Neuropilin-2, Beta 2 microglobulin, alpha-1-antichymotrypsin, and complement component C9, that were more abundant in HF patients in relation to disease severity and pulmonary dysfunction. Moreover, we showed the ability of the combination of these candidate proteins to discriminate, with sufficient accuracy, HF patients from healthy subjects. In conclusion, we demonstrated the feasibility and potential of a proteomic workflow based on MRM mass spectrometry for the evaluation of multiple proteins in human plasma and the identification of a panel of biomarkers of HF severity.

New Potential Biomarkers for Chronic Kidney Disease Management-A Review of the Literature

The prevalence of chronic kidney disease (CKD) is increasing worldwide, and the mortality rate continues to be unacceptably high. The biomarkers currently used in clinical practice are considered relevant when there is already significant renal impairment compromising the early use of potentially successful therapeutic interventions. More sensitive and specific biomarkers to detect CKD earlier on and improve patients' prognoses are an important unmet medical need. The aim of this review is to summarize the recent literature on new promising early CKD biomarkers of renal function, tubular lesions, endothelial dysfunction and inflammation, and on the auspicious findings from metabolomic studies in this field. Most of the studied biomarkers require further validation in large studies and in a broad range of populations in order to be implemented into routine CKD management. A panel of biomarkers, including earlier biomarkers of renal damage, seems to be a reasonable approach to be applied in clinical practice to allow earlier diagnosis and better disease characterization based on the underlying etiologic process.

Quantification of Neonatal Fc Receptor and Beta-2 Microglobulin in Human Liver Tissues by Ultraperformance Liquid Chromatography-Multiple Reaction Monitoring-based Targeted Quantitative Proteomics for Applications in Biotherapeutic Physiologically-based Pharmacokinetic Models

Neonatal Fc receptor (FcRn) and beta-2 microglobulin (β2M) play an important role in transporting maternal IgG to fetuses, maintaining the homeostasis of IgG and albumin in human body, and prolonging the half-life of IgG- or albumin-based biotherapeutics. Little is known about the influence of age, gender and race, and interindividual variability of human FcRn and β2M on the protein level. In this study, an ultraperformance liquid chromatography-multiple reaction monitoring mass spectrometry-based targeted quantitative proteomic method was developed and optimized for the quantification of human FcRn and β2M. Among the 39 human livers studied (age 13-80 years), the mean (±S.D.) concentrations of FcRn and β2M were 147 (±39) and 1250 (±460) pmol/g of liver tissue, respectively. A four-fold interindividual variability (63-243 pmol/g of liver tissue) was observed for the hepatic FcRn concentration. A moderate correlation was found between the hepatic β2M and FcRn expression levels. Influences of age, gender, and race on the hepatic expression of FcRn and β2M were evaluated. The findings from this study may aid the development of physiologically-based pharmacokinetic models that incorporate empirical FcRn tissue concentrations and interindividual variabilities, and the development of personalized dosing of biopharmaceuticals. SIGNIFICANCE STATEMENT: This is the first study to evaluate the influence of age, gender, and race on the expression of neonatal Fc receptor (FcRn) and beta-2 microglobulin (β2M) and their interindividual variability in human livers. This study describes a validated ultraperformance liquid chromatography-multiple reaction monitoring-based targeted quantitative proteomic method for quantifying human FcRn and β2M in biological tissues. Results from this study may aid current development of physiologically-based pharmacokinetic models for biotherapeutics, where FcRn plays a significant role in clearance mechanism, and its expression level and interindividual variability are largely unknown.

Association of Bariatric Surgery With Rates of Kidney Function Decline Using Multiple Filtration Markers

This cohort study examines the association of bariatric surgery with rates of kidney function decline.

The inhibitory receptor CD94/NKG2A on CD8+ tumor-infiltrating lymphocytes in colorectal cancer: a promising new druggable immune checkpoint in the context of HLAE/β2m overexpression

We previously demonstrated that HLA-E/β2m overexpression by tumor cells in colorectal cancers is associated with an unfavorable prognosis. However, the expression of its specific receptor CD94/NKG2 by intraepithelial tumor-infiltrating lymphocytes, their exact phenotype and function, as well as the relation with the molecular status of colorectal cancer and prognosis remain unknown. Based on a retrospective cohort of 234 colorectal cancer patients, we assessed the expression of HLA-E, β2m, CD94, CD8, and NKp46 by immunohistochemistry on tissue microarray. The expression profile of HLA-E/β2m on tumor cells and the density of tumor-infiltrating lymphocytes were correlated to the clinicopathological and molecular features (Microsatellite status, BRAF and RAS mutations). Then, from the primary tumors of 27 prospective colorectal cancers, we characterized by multiparameter flow cytometry the nature (T and/or NK cells) and the co-expression of the inhibitory NKG2A or activating NKG2C chain of ex vivo isolated CD94+ tumor-infiltrating lymphocytes. Their biological function was determined using an in vitro redirected cytolytic activity assay. Our results showed that HLA-E/β2m was preferentially overexpressed in microsatellite instable tumors compared with microsatellite stable ones (45% vs. 19%, respectively, p = 0.0001), irrespective of the RAS or BRAF mutational status. However, HLA-E/β2m+ colorectal cancers were significantly enriched in CD94+ intraepithelial tumor-infiltrating lymphocytes in microsatellite instable as well as in microsatellite stable tumors. Those CD94+ tumor-infiltrating lymphocytes mostly corresponded to CD8+ αβ T cells, and  to a lesser extent to NK cells, and mainly co-expressed a functional inhibitory NKG2A chain. Finally, a high number of CD94+ intraepithelial tumor-infiltrating lymphocytes in close contact with tumor cells was independently associated with a worse overall survival. In conclusion, these findings strongly suggest that HLA-E/β2m-CD94/NKG2A represents a new druggable inhibitory immune checkpoint, preferentially expressed in microsatellite instable tumors, but also in a subgroup of microsatellite stable tumors, leading to a new opportunity in colorectal cancer immunotherapies.

The potential diagnostic power of CD138+ microparticles from the plasma analysis for multiple myeloma clinical monitoring

Multiple myeloma (MM) is malignant tumor with abnormal proliferation of bone marrow plasma cells. The existing clinical tools used to determine treatment response and tumor relapse are limited in sensitivity. We investigated the CD138+ microparticles (MPs) of MM patients to find out whether MPs could provide a novel means to monitor the malignant cells in MM patients. Our study showed that the levels of MPs were significantly elevated in MM patients. The MP counts in peripheral blood from new diagnosed MM patients were significantly higher than patients in CR and HD. Consist with the total MPs, the number of the PC-derived MPs (CD138+) increased in BM from MM patients compared with CR and HD. The ratio of the PC-derived MPs (CD138+) in BM increased in MM patients compared with CR and HD. The correlation test revealed that the CD138+ MPs in BM and PB were all positively correlated with the plasmacyte ratio in bone marrow (BMPC) and the β₂ -MG. New diagnosed MM patients and controls were compared, and ROC curves were used to identify cutoff points with optimal sensitivity and specificity concerning the ratios and counts of CD138+ MPs in BM and PB. The AUC of the CD138+ MP counts in BM was 0.767, and in PB was 0.680. The AUC of the CD138+ MP ratios in BM was 0.714, and in PB was 0.666. According to this, the counts of CD138+ MPs in BM showed to be a powerful marker of diagnosis. We demonstrated that CD138+ MPs from the plasma provide support for a potential monitoring biomarker of MM.

Discrepancy of Serological and Molecular Patterns of Circulating Epstein-Barr Virus Reactivation in Primary Sjögren's Syndrome

Primary Sjögren's syndrome (pSS) is characterized by B cell hyperactivation, production of autoantibodies and increased risk of B cell lymphomas. Serological profile of Epstein-Barr virus (EBV) reactivation and increase EBV DNA levels in exocrine glands are observed in pSS, but whether these abnormalities are accompanied with disturbed systemic EBV control or have any association with pSS activity remains to be investigated. In this observational study, we initially explored anti-EBV antibodies and cell-free DNA in 395 samples from a cross-sectional plasma collection of pSS patients included in ASSESS French national cohort. Results were assessed in relation with disease activity. Further, to assess cell-associated EBV DNA we organized a case-control study including 20 blood samples from pSS patients followed in University Hospital Center of Montpellier. Results were compared with matched controls. Robust response against EBV early antigen (EA) was observed in pSS patients with anti-SSA/B (Sjögren's syndrome A and B) and anti-SSA autoantibodies compared to anti-SSA/B negatives (P < 0.01 and P = 0.01, respectively). Increased beta-2 microglobulin, kappa and lambda light chains, and immunoglobulin G levels were more frequently observed in anti-EA seropositive pSS subjects compared to anti-EA negative subjects (P < 0.001; P = 0.001; P = 0.003, respectively). Beta-2 microglobulin was independently associated with anti-EA positivity in multivariate analysis (P < 0.001). Plasma cell-free EBV DNA and EBV cellular reservoir was not different between pSS patients and controls. We conclude that serological evidence of EBV reactivation was more frequently observed and more strongly associated with anti-SSA/B status and B cell activation markers in pSS. However, serological profile of EBV reactivation was not accompanied by molecular evidence of systemic EBV reactivation. Our data indicated that EBV infection remains efficiently controlled in the blood of pSS patients.

The relationships between markers of tubular injury and intrarenal haemodynamic function in adults with and without type 1 diabetes: Results from the Canadian Study of Longevity in Type 1 Diabetes

OBJECTIVE

Our aim was to define the relationships between plasma biomarkers of kidney injury and intrarenal haemodynamic function (glomerular filtration rate [GFR], effective renal plasma flow [ERPF], renal vascular resistance [RVR]) in adults with type 1 diabetes (T1D).

METHODS

The study sample comprised patients with longstanding T1D (duration ≥50 years), among whom 44 were diabetic kidney disease (DKD) resistors (eGFR >60 mL/min/1.73 m² and <30 mg/d urine albumin excretion) and 22 had DKD, in addition to 73 control participants. GFR_INULIN and ERPF_PAH were measured, RVR was calculated, and afferent (R_A )/efferent (R_E ) areteriolar resistances were derived from Gomez equations. Plasma neutrophil gelatinase-associated lipocalin (NGAL), β2 microglobulin (B2M), osteopontin (OPN) and uromodulin (UMOD) were measured using immunoassay kits from Meso Scale Discovery.

RESULTS

Plasma NGAL, B2M and OPN were higher and UMOD was lower in DKD patients vs DKD resistors and non-diabetic controls. In participants with T1D, plasma NGAL inversely correlated with GFR (r = -0.33; P = 0.006) and ERPF (r = -0.34; P = 0.006), and correlated positively with R_A (r = 0.26; P = 0.03) and RVR (r = 0.31; P = 0.01). In participants without T1D, NGAL and B2M inversely correlated with GFR (NGAL r = -0.18; P = 0.13 and B2M r = -0.49; P < 0.0001) and with ERPF (NGAL r = -0.19; P = 0.1 and B2M r = -0.42; P = 0.0003), and correlated positively with R_A (NGAL r = 0.19; P = 0.10 and B2M r = 0.3; P = 0.01) and with RVR (NGAL r = 0.20; P = 0.09 and B2M r = 0.34; P = 0.003). Differences were significant after adjusting for age, sex, HbA1c, SBP and LDL. There were statistical interactions between T1D status, B2M and intrarenal haemodynamic function (P < 0.05).

CONCLUSIONS

Elevated NGAL relates to intrarenal haemodynamic dysfunction in T1D, whereas elevated NGAL and B2M relate to intrarenal haemodynamic dysfunction in adults without T1D. These data may define a diabetes-specific interplay between tubular injury and intrarenal haemodynamic dysfunction.

Current approaches to middle molecule removal: room for innovation

Aggressive removal of middle molecules or larger low-molecular-weight proteins (LMWPs) has been a growing concern following studies on their harmful effects on the mortality and morbidity of chronic dialysis patients. To remove larger LMWPs and some protein-bound uremic toxins (PBUTs), high- and medium-cutoff (HCOs and MCOs, respectively) membranes, convective therapy and protein adsorptive membranes are available. When we use HCO or MCO membranes for convective therapy, we have to take care to avoid massive albumin leakage during a dialysis session. Convection volume is an important element to increase middle molecule removal; however, a larger convection volume has a risk of larger leakage of albumin. Predilution hemodiafiltration is a useful measurement to increase larger LMWPs without massive albumin leakage. β2-microglobulin (B2M), α1-microglobulin (A1M) and albumin leakage during a dialysis session are useful parameters for assessing middle-molecule removal. Reduction ratios of B2M >80% and of A1M >35% are favorable to improve severe dialysis-related symptoms. The efficacy of middle molecule removal should be evaluated in comparison with clinical outcomes, mortality, morbidity and the improvement of dialysis-related symptoms. Recently some dialysis-related symptoms such as sleep disturbance, skin itchiness and dialysis hypotension have been recognized as good surrogate makers for mortality. Further studies to evaluate the relationship between middle molecule or PBUTs removal and the improvement of patient symptoms should be performed in well-designed randomized controlled trials.

Simultaneous Plasma Determination of CEA, HCG-Beta and Beta-2-Microglobulin in Patients with Nontrophoblastic Tumors

With the object of studying the possible usefulness of the simultaneous plasma determination of CEA, HCG-beta and beta 2-microglobulin in patients with nontrophoblastic tumors, we measured by radioimmonoassay the concentrations of these substances in 77 patients with normal renal function. In the group without metastases (32 cases), the percentages of positivities were low and similar for the 3 tumor markers. In the group with metastases (45 cases), the χ2 test of independence between each of the 2 markers at a level of 95 % showed a relationship between the results obtained in the determination of HCG-beta and beta 2-microglobulin, as well as an independence between CEA and HCG-beta results and CEA and beta 2-microglobulin results. These data suggest the utility of determining CEA with only 1 of the other 2 antigens in disseminated tumors.

Serum Tumor Markers in Non-Hodgkin's Lymphomas and Chronic Lymphocytic Leukemia

The levels of soluble interleukin-2 receptors (sIL-2R), beta-2 microglobulin (β-2M), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured in the serum of 50 previously untreated patients with non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukemia (CLL) as well as in 25 age and sex-matched normal controls. Compared to normal controls, mean serum levels of sIL-2R and β-2M were significantly increased in both NHL and CLL (p < 0.001) while the increase in ESR and CRP was less marked (p < 0.01 and p < 0.05, respectively). Comparison of these tumor markers with histologic grading showed statistically significant differences only for CRP between low, intermediate and high-grade lymphomas (p < 0.001 and p < 0.05). More advanced stages exhibited higher mean values of all serum markers than early stages (p < 0.001 for sIL-2R, β-2M and ESR and p < 0.05 for CRP). An association with the presence of b-symptoms was observed only for sIL-2R (p < 0.05). In addition, sIL-2R as well as β-2M were able to predict time to progression in patients with diffuse large-cell lymphomas.

We conclude that of the four tumor markers tested sIL-2R and β-2M more frequently showed increased serum levels and were associated with clinical stage and/or presence of b-symptoms. Both sIL-2R and β-2M were also found to have prognostic significance for survival.

Spatially Resolved Peptide-DNA Nanoassemblages for Biomarker Detection: A Synergy of DNA-Directed Immobilization and Nanografting

Peptide microarrays are becoming a promising alternative to protein microarrays due to the challenges associated with protein immobilization and purification. Here, we put forward a novel experimental-based approach that combines DNA-directed immobilization, nanografting, and atomic force height measurements to immobilize computationally designed cyclic peptide on an ultra-flat gold substrate. This procedure yields peptide-DNA nanoarrays, which can bind to the solvent-exposed site on the Beta-2-microglobulin (β2m).

Predictive value of plasma β2-microglobulin on human body function and senescence

OBJECTIVE

To explore the correlation between plasma β2-microglobulin (β2-MG) as senescence factor with age, heart, liver and kidney function as well as the predictive value of β2-MG in human metabolism function and senescence.

PATIENTS AND METHODS

387 cases of healthy people of different ages were selected and the automatic biochemical analyzer was used to test β2-MG in plasma based on immunoturbidimetry and also all biochemical indexes. The correlation between β2-MG and age, gender and all biochemical indexes was analyzed.

RESULTS

β2-MG was positively correlated to age, r = 0.373; and the difference was of statistical significance (p < 0.010). It was significantly negative correlated to HDL-C but positively correlated to LP (a), BUN, CREA, UA, CYS-C, LDH, CK-MB, HBDH, AST, GLB and HCY.

CONCLUSIONS

β2-MG was closely correlated to age, heart, kidney and liver biochemical indexes, which can be taken as an important biomarker for human body function and anti-senescence and have significant basic research and clinical guidance values.

Dialyzer Reuse and Outcomes of High Flux Dialysis

Background

The bulk of randomized trial evidence for the expanding use of High Flux (HF) hemodialysis worldwide comes from two randomized controlled trials, one of which (HEMODIALYSIS, HEMO) allowed, while the other (Membrane Outcomes Permeability, MPO) excluded, the reuse of membranes. It is not known whether dialyzer reuse has a differential impact on outcomes with HF vs low flyx (LF) dialyzers.

Methods

Proportional Hazards Models and Joint Models for longitudinal measures and survival outcomes were used in HEMO to analyze the relationship between β2-microglobulin (β2M) concentration, flux, and reuse. Meta-analysis and regression techniques were used to synthesize the evidence for HF dialysis from HEMO and MPO.

Findings

In HEMO, minimally reused (< 6 times) HF dialyzers were associated with a hazard ratio (HR) of 0.67 (95% confidence interval, 95%CI: 0.48–0.92, p = 0.015), 0.64 (95%CI: 0.44 – 0.95, p = 0.03), 0.61 (95%CI: 0.41 – 0.90, p = 0.012), 0.53 (95%CI: 0.28 – 1.02, p = 0.057) relative to minimally reused LF ones for all cause, cardiovascular, cardiac and infectious mortality respectively. These relationships reversed for extensively reused membranes (p for interaction between reuse and flux < 0.001, p = 0.005) for death from all cause and cardiovascular causes, while similar trends were noted for cardiac and infectious mortality (p of interaction between reuse and flux of 0.10 and 0.08 respectively). Reduction of β2M explained only 1/3 of the effect of minimally reused HF dialyzers on all cause mortality, while non-β2M related factors explained the apparent attenuation of the benefit with more extensively reused dialyzers. Meta-regression of HEMO and MPO estimated an adjusted HR of 0.63 (95% CI: 0.51–0.78) for non-reused HF dialyzers compared with non-reused LF membranes.

Conclusions

This secondary analysis and synthesis of two large hemodialysis trials supports the widespread use of HF dialyzers in clinical hemodialysis over the last decade. A mechanistic understanding of the effects of HF dialysis and the reuse process on dialyzers may suggest novel biomarkers for uremic toxicity and may accelerate membrane technology innovations that will improve patient outcomes.

PET/CT Assessment of Follicular Lymphoma and High Grade B Cell Lymphoma - Good Correlation with Clinical and Histological Features at Diagnosis

BACKGROUND

Follicular lymphoma is a common type of non-Hodgkin's lymphoma observed in Western countries. The diagnosis of this disease is based primarily on morphological and immunohistochemical assessment. The proliferative index Ki67 correlates with histological grading and clinical aggressiveness. Currently, positron emission tomography/computed tomography scanning are not applied for standard staging at diagnosis of follicular lymphoma and its use is limited to those patients for whom the identification of residual disease is crucial for therapeutic decisions and only when transformation to a high-grade lymphoma is suspected.

OBJECTIVES

Our aim was to assess whether a correlation exists between the maximal standardized uptake value (SUVmax) at the biopsy site as detected via positron emission tomography/computed tomography and pathological (Ki67 and FL histological grade) and clinico-biological features (e.g. LDH, beta-2-microglobulin, Ann Arbor stage and FL International Prognostic Index--FLIPI) at diagnosis.

MATERIAL AND METHODS

We retrospectively identified 16 patients during the previous 3.5 years in whom node biopsies were guided, taking into account the SUVmax as detected upon PET/CT scan at diagnosis. The results of these biopsies were diagnostic of follicular lymphoma. We also included 6 patients with high grade B cell lymphoma: 5 diffuse large B cell lymphoma (DLBCL) and 1 FL 3b histological grade. A 2-tailed non-parametric Spearman's correlation analysis of the SUVmax with Ki67, histological grade, LDH and b-2-microglobuline was performed.

RESULTS

The Ki67 (r=0.73) and follicular lymphoma histological grade (r=0.75) at the biopsy displayed a significant correlation with the SUVmax at diagnosis (p<0.01).

CONCLUSIONS

Our results suggest that SUV detected by positron emission tomography/computed tomography correlates with histological grade in follicular lymphoma/high grade B cell lymphoma, Ki67 and LDH. Positron emission tomography/computed tomography should be considered for guiding lymph node biopsy when transformation to a high-grade B cell lymphoma is suspected.

Airway symptoms and biological markers in nasal lavage fluid in subjects exposed to metalworking fluids

BACKGROUNDS

Occurrence of airway irritation among industrial metal workers was investigated. The aims were to study the association between exposures from water-based metal working fluids (MWF) and the health outcome among the personnel, to assess potential effects on the proteome in nasal mucous membranes, and evaluate preventive actions.

METHODS

The prevalence of airway symptoms related to work were examined among 271 metalworkers exposed to MWF and 24 metal workers not exposed to MWF at the same factory. At the same time, air levels of potentially harmful substances (oil mist, morpholine, monoethanolamine, formaldehyde) generated from MWF was measured. Nasal lavage fluid was collected from 13 workers and 15 controls and protein profiles were determined by a proteomic approach.

RESULTS

Airway symptoms were reported in 39% of the workers exposed to MWF although the measured levels of MWF substances in the work place air were low. Highest prevalence was found among workers handling the MWF machines but also those working in the same hall were affected. Improvement of the ventilation to reduce MWF exposure lowered the prevalence of airway problems. Protein profiling showed significantly higher levels of S100-A9 and lower levels of SPLUNC1, cystatin SN, Ig J and β2-microglobulin among workers with airway symptoms.

CONCLUSIONS

This study confirms that upper airway symptoms among metal workers are a common problem and despite low levels of MWF-generated substances, effects on airway immune proteins are found. Further studies to clarify the role of specific MWF components in connection to airway inflammation and the identified biological markers are warranted.

Cut-off levels of salivary beta2-microglobulin and sodium differentiating patients with Sjögren's syndrome from those without it and healthy controls

OBJECTIVES

For the diagnosis of Sjögren's syndrome (SS), cut-off levels of β2-microglobulin (β2MG) and sodium (Na+) in unstimulated whole saliva have not yet been shown. We aimed to determine the cut-off levels of salivary β2MG and Na+ which differentiate SS patients from non-SS patients and healthy controls.

METHODS

Seventy-one patients of primary SS (pSS, 69 females/2 males, 60.0±16.8 years old), 50 of secondary SS (sSS, 49/1, 55.8±17.4), 54 of connective tissue diseases other than SS (non-SS-CTD, 43/11, 60.0±16.0), and 75 healthy volunteers (HC, 43/32, 50.7±15.6) were included. Unstimulated whole saliva were examined for levels of β2MG, Na+, potassium (K+), and chloride (Cl-). Receiver-operating characteristic curve analysis was carried out.

RESULTS

β2MG, Na+, and Cl- levels in the SS group (pSS and sSS) were significantly higher than those in the non-SS group (non-SS-CTD and HC). The salivary β2MG level was 5.3±4.6 mg/L in pSS, 5.1±2.0 in sSS, 2.5±2.1 in non-SS-CTD, and 1.2±0.7 in HC, respectively. The Na+ level was 39.2±25.2 mEq/L, 36.4±26.1, 19.6±16.8, and 16.5±7.3, and the Cl- level was 51.1±25.0, 47.8±24.3, 32.1±16.6, and 27.0±7.9 in the same order. The K+ level in the SS group was significantly higher than that in HC. The optimal cut-off β2 MG and Na+ levels that differentiate the SS group from the non-SS group were 2.3 mg/L and 23 mEq/L.

CONCLUSIONS

Salivary β2MG and Na+ levels are useful markers for differentiating SS patients from non-SS-CTD patients and HC.

Proteomics of tear fluid in thyroid-associated orbitopathy

BACKGROUND

Proteomics and mass spectrometry are useful tools for peptide screening in body fluids. In thyroid-associated orbitopathy (TAO), evidence for lacrimal gland involvement with altered composition of tears has been reported. Our objective was to detect and evaluate potential changes in the proteomic patterns of tear fluid in TAO.

METHODS

Tear fluid was collected from 45 patients with TAO and 15 healthy controls. Tear proteins were analyzed using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry, and peptides were identified using matrix-assisted laser desorption/ionization time-of-flight technology.

RESULTS

Peptides with molecular weights 3808 Dalton (Da, p=0.004), 3734 Da (p=0.034), and 3837 Da (p=0.042), respectively, were downregulated in patients with TAO versus controls. They were identified as proline-rich protein 4 (PRP4) or as its variant nasopharyngeal carcinoma-associated PRP4. The peptide 3837 Da correlated positively with the basal secretory test (r=0.506, p<0.001) and negatively with the clinical activity score (r = -0.334, p<0.05) and age (r=-0.431, p<0.001). Also, a 12,003-Da peptide was downregulated (p=0.019) in patients and identified as ß2-microglobulin. This peptide decreased in tear fluid with increased clinical severity of TAO (p=0.027). In comparison, a 5815-Da peptide was upregulated (p=0.045) and identified as lysozyme C. When differentiating between treated and untreated patients with TAO, an 11,770-Da peptide (p=0.0072) that was also upregulated was identified as cystatin S.

CONCLUSIONS

Altered regulation of proinflammatory and protective proteins in tears of patients with TAO was demonstrated, reflecting an autoimmune- and/or inflammatory-induced dysfunction of the lacrimal gland.

[Clinical features and outcome analyses of newly-diagnosed multiple myeloma with extramedullary involvements]

OBJECTIVE

To explore the clinical features and prognostic factors of newly-diagnosed multiple myeloma (MM) with extramedullary (EM) involvements.

METHODS

The clinical features, efficacies, survival rates and prognostic factors were retrospectively analyzed in 46 MM patients with EM (group A) from January 2000 to October 2011. And another 53 MM patients without EM (group B) were selected as the controls.

RESULTS

The median age of Group A was 58 years. Compared with group B, the incidence of EM was associated with a higher level of β2-microglobulin (β2-MG) and extensive bone disease. The most common location of EM was soft tissues. And the total effective rates of groups A and B were 58.5% (24/41) and 78.8% (41/52) respectively. The difference was statistically significant (P = 0.042). The median follow-up time was 28(2-88) months. The estimated overall survival (OS) of the patients with EM was significantly shorter than those without EM (42.6 vs 53.9 months, P = 0.009). Log-rank univariate analysis showed that the number of osteolytic lesions ≥ 3, β2-MG ≥ 5.5 mg/L, hemoglobin ≤ 110 g/L and albumin ≤ 30 g/L were poor prognostic factors in MM patients with EM. Multivariate analysis with Cox model showed only the number of osteolytic lesions ≥ 3 (OR = 2.327, 95%CI: 1.282 - 4.224) and β2-MG ≥ 5.5 mg/L (OR = 2.677, 95%CI: 1.092 - 6.566) were statistically significant.

CONCLUSIONS

Multiple EM lesions may be involved in MM patients. For the patients with EM, the response to conventional chemotherapy is poor and the prognosis is unfavorable, especially for those with a high level of β2-MG or the number of osteolytic lesions ≥ 3.

Additional genetic abnormalities significantly worsen poor prognosis associated with 1q21 amplification in multiple myeloma patients

We investigated the prognostic value of amp(1q21) alone and in combination with other abnormalities in newly diagnosed myeloma patients. The study group consisted of 104 patients treated with various induction regimens, mostly thalidomide based (87 patients). Amp(1q21) was detected in 49 (47.1%) of patients; in 26 (25.0%) cases, it was combined with del(13q14), in 7 (6.7%) with del(17p13) and in 15 (14.4%) with t(4;14)(p16;q32). The response rate was significantly better in amp(1q21)-negative than in amp(1q21)-positive patients (74.5% vs 55.1%, p = 0.025; complete response 18.2% vs 4.1%, p = 0.024). The median progression-free survival (PFS) was 33.9 months in patients without amp(1q21) and 10.3 months with this aberration (p = 0.002). The presence of additional abnormalities resulted in significantly shortened PFS when compared with patients with isolated amp(1q21): coexisting del(13q14) resulted in 7.8 vs 29.0 months of PFS (p = 0.024) and del(17p13) resulted in 4.0 vs 24.9 months of PFS (p = 0.034). The presence of amp(1q21) significantly influenced overall survival (OS) as well as PFS resulting in the median OS of 26.6 vs 62.4 months (p = 0.018) in patients without amp(1q21). The presence of additional genetic abnormalities significantly affected OS when compared with patients carrying isolated amp(1q21): for del(13q14) 18.9 vs 58.4 months (p = 0.004) and for del(17p13) 12.0 vs 46.5 months (p = 0.036). On multivariate analysis amp(1q21), del(13q14) and del(17p13) were found to be an independent adverse predictors of shorter PFS and OS. Our results showed that the presence of amp(1q21) was associated with poor prognosis. Moreover additional genetic abnormalities made PFS and OS further shortened.

B cell-activating factor: its clinical significance in multiple myeloma patients

B cell-activating factor (BAFF) is a cytokine that plays a major role in the maintenance of normal B-cell development and homeostasis. It has been suggested that in multiple myeloma (MM) it might have regulatory effects on the proliferation and viability of malignant plasma cells. The aim of this study was to evaluate serum levels of BAFF in 52 newly diagnosed MM patients, with varying disease severity, in order to see the correlations between BAFF and indices of MM activity, such as interleukin-6, C-reactive protein, lactate dehydrogenase, and beta-2 microglobulin, and to explore the clinical significance of BAFF in predicting the disease activity of MM. We found increased BAFF serum levels in MM patients, increased in advanced stages, and decreased in plateau phase. We also found significant correlations between BAFF serum levels with the above parameters of disease activity. We conclude that BAFF may play an important role in pathogenesis of MM, could be used as a marker of disease activity, and a possible therapeutic target.

Serum calcium is an independent prognostic factor of overall survival in Mexican patients with multiple myeloma

OBJECTIVE

To evaluate the impact of different prognostic factors that has been suggested to be useful in predicting the survival of patients with multiple myeloma (MM).

MATERIALS AND METHODS

A longitudinal prospective study was conducted on 24 adult Mexican patients diagnosed with primary MM. The levels of expression of CD38, CD138 and cyclin D1 were analyzed in plasma cells (PCs) from patients and mononuclear cells from healthy donors. Serum levels of lactate dehydrogenase, creatinine, calcium, beta2 microglobulin and interleukin-6 (IL-6) as well as hemoglobin and platelet count were taken into consideration. RESULTS; CD138 and cyclin D1 levels in absolute numbers were significantly overexpressed in malignant PCs. A positive correlation was noted between cyclin D1 and CD38 expression levels in malignant PCs. IL-6 and serum calcium were also positively correlated in MM patients. Cyclin D1 overexpression was not associated with better overall survival (OS). Normal calcium levels were associated with better overall survival (OS). Serum calcium was the only variable correlating with better OS in Cox regression analysis.

CONCLUSION

Serum calcium is an independent prognostic factor of OS in a population of Mexican patients with MM.

Albumin loss under the use of the high-performance membrane

Beta-2-microglobulin (β(2)M) clearance has been improved in recent dialysis membranes and minimum albumin leakage has been achieved in most membranes today since dialysis membranes are now classified by β(2)M clearance in terms of the reimbursement by health insurance. Kawanishi et al. suggested that 'the desirable albumin leakage in one treatment is less than 4 g '. Function classification type IV or type V dialysis membranes have leakages as low as 3 g, while most resulted in < 1 g leakage. However, some high-performance membranes (HPMs) have around 8 g of leakage, which requires further study of the clinical efficacy using such dialysis membranes. The comparison of albumin leakage in one dialysis treatment (4 h: blood flow volume of 250 ml/min) revealed that PES-210D has an overwhelmingly high albumin leakage of 7.69 ± 1.01 g. The data were without any significant difference between the PES-D membrane user group and the non-PES-D membrane user group for hemoglobin, hematocrit, β(2)M protein, catabolic rate, body mass index, and muscle mass. However, the PES-D membrane user group had a significantly lower number of hospitalizations and other complication events. When comparing the event contents, the PES-D membrane user group had no cardiac failure and lower DRA, however it had more vascular access problems. In normal renal function, approximately 10 g of albumin is filtered in the glomerulus per day, decomposed in the renal tubule and reabsorbed as amino acid, and re-synthesized into albumin in the liver. On the contrary, in dialysis patients, albumin that is bound to biologically active substances and/or the oxidized form of albumin that has lost its antioxidant effect cannot be filtered from the kidney and accumulate. Therefore, the idea regarding albumin leakage is to remove biologically active substances that bind to albumin and function as uremic toxin, remove albumin without the antioxidant effect, and facilitate synthesis of new albumin with an antioxidant effect.

The dynamic range problem in the analysis of the plasma proteome

One of the greatest challenges in analyzing the plasma proteome is the wide range of concentration of different proteins. The current study examines the range of protein concentration for 18 proteins measured over a year in a clinical laboratory to provide data on pathological extremes in protein concentrations. The complete measured range, from upper limits for albumin to lowest values for thyroid-stimulating hormone (TSH), represented more than 10 logs of molar abundance. A number of plasma proteins measured in the clinical laboratory varied over a concentration range spanning more than 4 logs, and limits of detection of clinical assays were inadequate to assess full concentration ranges of several proteins. Considering reported values from studies using higher sensitivity assays suggest that plasma concentrations of prostate-specific antigen (PSA), human chorionic gonadotropin (hCG), and cardiac troponin I vary by more than 7 logs. All of the plasma proteins measured in the present study represent secretory proteins or highly expressed components of specific tissues. Thus, the dynamic range for these components is likely to greatly underestimate the total range of protein concentration in the plasma proteome.

Serum CA 125 as a Prognostic Factor in Non-Hodgkin's Lymphoma

Cancer antigen 125 (CA 125) is a glycoprotein expressed in normal tissues originally derived from coelomic epithelia such as peritoneum, pleura, pericardium, fallopian tubes and endometrium. Serum CA 125 levels are elevated in various benign and malignant conditions that involve stimulation of these tissues. Although elevated levels have been reported in patients with non-Hodgkin's lymphoma (NHL), its role as a prognostic factor remained uncertain. In this study, serum CA 125 levels were measured prospectively in 108 consecutive patients with NHL: at diagnosis in 106, in remission in 39 and at relapse in 7. Levels were elevated in 43% at diagnosis. This finding was associated with advanced disease stage, bulky tumors, bone marrow involvement, extranodal disease (in stages III and IV), occurrence of B symptoms, pleural or peritoneal effusions, high serum LDH levels, high serum beta2 microglobulin (beta2-M) levels, elevated International Prognostic Score, poor performance status and partial or no response to treatment. No difference in CA 125 level was found between the indolent and aggressive lymphomas. Serum CA 125 levels at diagnosis had strong association with event-free and overall survival (p = 0.01 and 0.003, respectively), with the patients with increased levels having worse survival. Patients with high CA 125 levels at diagnosis who achieved remission showed a significant decrease in CA 125 levels in remission. In conclusion, CA 125 is not only a reliable marker for staging and assessing tumor activity in NHL, elevated levels are also predictive of decreased survival.

Bone marrow histology and serum beta 2 microglobulin in multiple myeloma--a new prognostic strategy

Bone marrow biopsies of 720 patients with multiple myeloma (MM) were investigated from 1968-1989. Histologic variables were correlated with clinical parameters and survivals to determine prognostic factors. In 207 of these patients initial levels of serum beta 2 microglobulin (SB2M) were also measured for prognostic evaluation. Four tumour growth patterns were distinguished: interstitial (56%), interstitial/sheets (13%), nodular (15%) and packed marrow (16%) with median survivals of 46, 31, 22 and 16 months. When grouped according to the tumour cell mass in the biopsy, four histologic stages were recognized. Cellular characteristics were used to classify MM into 6 histologic types which were subsequently combined into 3 grades of malignancy: low, intermediate and high, analogous to the malignant lymphomas. With respect to tumour products, only SB2M proved to be a valuable prognostic indicator for staging and follow-up. Complications of MM such as anaemia, azotaemia, osteolytic lesions, hypercalcaemia and hypoalbuminaemia all predicted a poor prognosis, highly significant in the test statistics. We propose a new prognostic approach in MM, comprising 1) parameters defining the tumour itself, 2) the tumour products (SB2M) and 3) the tumour complications. This prognostic strategy combines information both on stage and malignancy of MM and enables definition of smouldering and of aggressive variants of MM at an early stage.

Therapeutic implications of myeloma staging

Clinical staging, such as with the Durie-Salmon clinical staging method, remains the most easily usable available method to classify patients with untreated multiple myeloma. However, for the development of new treatment strategies and comparison with prior results, new and powerful prognostic factors are now available. Serum beta 2 microglobulin alone represents the most reliable prognostic factor in multiple myeloma. Beta 2 microglobulin alone allows simple and reproducible classification of patients into low grade myeloma with low serum beta 2 microglobulin versus high grade myeloma with high serum beta 2 microglobulin. Plasma cell labelling index is an additional factor which allows identification of patients with MGUS as well as subclassification of patients with low serum beta 2 microglobulin into those with relatively better or worse prognosis. For each grade of myeloma young (less than 63 years of age) patients have a slightly better survival. Independently of serum beta 2 microglobulin and labelling index, DNA content values allow the identification of a subset of patients with biclonal or hypodiploid tumors and high grade disease. New or more sophisticated methods for evaluating myeloma cells such as by immunophenotyping or assessment of multi drug resistance enable the development of specific approaches to treatment in individual cases. It should also prove possible to identify patients especially suitable for newer biologic agents such as alfa interferon, G or G-MCSF and the various interleukins.

The effects of cimetidine (Tagamet) on renal function in patients with renal failure

Cimetidine has been administered during 7 days to 28 patients with different degrees of renal failure. Thirteen of these patients had a further week's treatment at least one month later. The daily dose of cimetidine was reduced in relation to pretrial values of creatinine clearance. There was a clear rise in serum creatinine all through the trial (22.3 +/- 2.6% at day 7) (p < 0.001). Maximal decreases in creatinine clearance occurred on day 2 (21.8 +/- 2.2%) and day 3 (23 +/- 2.0%) (p < 0.001), but were still present on days 6 (16.4 +/- 2.9%) and 7 (17.3 +/- 2.8%) (p < 0.001). There was a small rise in serum uric acid all through the trial (p < 0.05). Three days after finished treatment there were no significant differences in serum creatinine, creatinine clearance and serum uric acid when compared to pretrial values. The pattern of changes in serum creatinine and creatinine clearance was the same in both mild and severe renal failure. Glomerular filtration rate determined by |52Cr¿ EDTA clearance before, on day 3 of treatment and 3 days after treatment did not show any differences. No change was seen in serum beta 2-microglobulin during the trial. The decrease in creatinine clearance during treatment with cimetidine is probably not caused by a reduction of glomerular filtration rate, but could be explained by competition by cimetidine for tubular secretion of creatinine. Treatment with cimetidine of patients with renal failure may invalidate measurements of serum creatinine and creatinine clearance as standard routine tests for glomerular filtration rate.