Association between Thymosin beta-4, acute kidney injury, and mortality in patients with sepsis: An observational cohort study.

BACKGROUND: Sepsis is a systemic inflammatory response syndrome, associated with high risk of acute kidney injury (AKI) and in-hospital mortality. Thymosin beta-4 (Tß4) is an actin-sequestering protein that can prevent inflammation in several tissues. Thus, we studied the role of Tß4 in sepsis. METHODS: The Tß4 concentrations were prospectively measured in 191 patients within 6 h of the intensive care units (ICU) admission with diagnosis of sepsis. The cohort was divided into Tß4 concentration tertiles: 1.19-7.11 ng/ml (n = 64), 7.12-11.01 ng/ml (n = 64), and 11.02-28.10 ng/ml (n = 63). RESULTS: Of 191 patients, 92 patients developed AKI, 24 of whom received continuous renal replacement therapy (CRRT), 29 patients died within 7 days, and 53 patients died within 28 days. Lower Tß4 stages were correlated with poor prognosis, including AKI(odds ratio [OR], 2.102 per stage lower; 95% confidence interval [CI], 1.448 to 3.050; P < 0.001), CRRT(OR, 2.346 per stage lower; 95% CI, 1.287 to 4.276; P = 0.005), 7-day mortality(OR, 1.755 per stage lower; 95% CI, 1.050 to 2.935; P = 0.032), and 28-day mortality(OR, 1.821 per stage lower; 95% CI, 1.209 to 2.743; P = 0.004). Kaplan-Meier analysis also demonstrated that patients with lower Tß4 stages had a high risk of AKI and death. In addition, the area under the curve (AUC) of Tß4 for predicting AKI, CRRT, 7-day mortality, and 28-day mortality were, respectively, 0.702 (95% CI 0.628-0.776), 0.717 (95% CI 0.592-0.842), 0.694 (95% CI 0.579-0.808), and 0.682 (95% CI 0.598-0.767). CONCLUSIONS: Lower Tß4 stages are associated with higher odds of poor prognosis in ICU patients with sepsis.

F-Actin is associated with a worsening qSOFA score and intensive care unit admission in emergency department patients at risk for sepsis.

Objective: We previously demonstrated that plasma levels of F-actin and Thymosin Beta 4 differs among patients with septic shock, non-infectious systemic inflammatory syndrome and healthy controls and may serve as biomarkers for the diagnosis of sepsis. The current study aims to determine if these proteins are associated with or predictive of illness severity in patients at risk for sepsis in the Emergency Department (ED).Methods: Prospective, biomarker study enrolling patients (>18 years) who met the Shock Precautions on Triage Sepsis rule placing them at-risk for sepsis.Results: In this study of 203 ED patients, F-actin plasma levels had a linear trend of increase when the quick Sequential Organ Failure Assessment (qSOFA) score increased. F-actin was also increased in patients who were admitted to the Intensive Care Unit (ICU) from the ED, and in those with positive urine cultures. Thymosin Beta 4 was not associated with or predictive of any significant outcome measures.Conclusion: Increased levels of plasma F-actin measured in the ED were associated with incremental illness severity as measured by the qSOFA score and need for ICU admission. F-actin may have utility in risk stratification of undifferentiated patients in the ED presenting with signs and symptoms of sepsis.

Protective Effect of Thymosin ß4 against Abdominal Aortic Ischemia-Reperfusion-Induced Acute Lung Injury in Rats.

Background and objectives: Ischemia-reperfusion (IR) caused by infrarenal abdominal aorta cross-clamping is an important factor in the development of ischemia-reperfusion injury in various distant organs. Materials and Methods: We investigated potential antioxidant/anti-inflammatory effects of thymosin beta 4 (Tß4) in a rat model of abdominal aortic surgery-induced IR. Tß4 (10 mg/kg, intravenous (i.v.)) was administered to rats with IR (90-min ischemia, 180-min reperfusion) at two different periods. One group received Tß4 1 h before ischemia, and the other received 15 min before the reperfusion period. Results: Results were compared to control and non-Tß4-treated rats with IR. Serum, bronchoalveolar lavage fluid and lung tissue levels of oxidant parameters were higher, while antioxidant levels were lower in the IR group compared to control. IR also increased inflammatory cytokine levels. Tß4 reverted these parameters in both Tß4-treated groups compared to the untreated IR group. Conclusions: Since there is no statistical difference between the prescribed results of both Tß4-treated groups, our study demonstrates that Tß4 reduced lung oxidative stress and inflammation following IR and prevented lung tissue injury regardless of timing of administration.

Comparative proteomic analysis of plasma of children with congenital heart disease.

Congenital heart disease is one of the largest class of birth defects. Eight subjects with ventricular septal defect (VSD, a kind of congenital heart disease) and 11 health children were enrolled in tandem mass tags label-based quantitative proteomic analysis to compare plasma proteins differentially abundance. A total of 66 proteins were significantly upregulated or downregulated in VSD patients compared with healthy children. These proteins were involved in pathways linked to platelet activation, fructose and mannose metabolism, complement and coagulation cascades, glycolysis/gluconeogenesis, regulation of actin cytoskeleton, and carbon metabolism. The amount of ten proteins changed significantly (p < 0.05) in newly recruited 30 VSD compared with 15 control children, which were validated by ELISA. The areas under the receiver operating characteristic curve values of fructose-bisphosphate aldolase B (ALDOB) and thymosin beta-4 (Tß4) were higher than those of other candidate proteins. ALDOB and Tß4 might be potential biomarkers applied for identifying VSD in the further works.

Association between thymosin beta4 and non-alcoholic fatty liver disease.

BACKGROUND AND AIMS: non-alcoholic fatty liver disease (NAFLD) is the most common type of chronic liver injury worldwide. Some studies have shown that thymosin beta4 (Tß4) is closely related to liver diseases. Nevertheless, only a few published studies have reported the relationship between Tß4 and NAFLD. The purpose of this study was to evaluate the levels of Tß4 in patients with NAFLD compared with controls and to validate their relationship in a larger cohort. PATIENTS AND METHODS: a total of 76 NAFLD patients and 130 healthy controls were included in the study. Serum levels of Tß4, IL-6 and adiponectin were determined by ELISA. Serum glucose, insulin and lipids, as well as liver function were measured. Multivariate statistical analyses were performed via logistic regression modelling to determine the predictors with a significant relevance to NAFLD. The association between serum Tß4 and study variables was tested using correlation coefficients calculations. RESULTS: serum Tß4 content was 3.20 ± 0.98 mg/l in NAFLD patients (n = 76) and 5.53 ± 1.24 mg/l in healthy controls (n = 130); the difference between the two groups was statistically significant (p = 0.000). Multivariate logistic regression analysis identified Tß4 (OR = 0.343, 95% CI 0.240-0.491, p < 0.001), LDL (OR = 1.019, 95% CI 1.007-1.030, p = 0.001), ALT (OR = 1.021, 95% CI 1.001-1.041, p = 0.040) and IL-6 (OR = 1.443, 95% CI 1.079-1.929, p = 0.013) as independent predictors of NAFLD diagnosis. Serum Tß4 levels had a significant negative correlation with total cholesterol, TG, AST, GGT and IL-6 (p < 0.05 for all) and the correlation coefficient values were -0.163, -0.253, -0.143, -0.245 and -0.155, respectively. Serum Tß4 levels were positively correlated with serum adiponectin levels, with a correlation coefficient value of 0.143. CONCLUSION: serum Tß4 may play a defensive role in the development of NAFLD. Further studies are needed to confirm the role of Tß4 in NAFLD.

Quantification of protein markers monitoring the pre-analytical effect of blood storage time before plasma isolation using 15 N metabolically labeled recombinant proteins.

In the hospital, blood samples are collected to monitor patients' health states, and thus various protein-based clinical methods have been developed. However, some proteins are found to change in abundances during the process of blood collection and storage. In order to account such pre-analytical effects, we performed liquid chromatography multiple reaction monitoring mass spectrometry (LC-MRM-MS) on 15 selected proteins in plasma samples prepared by varying storage time and temperature of whole blood prior to plasma isolation. Two cytosolic proteins, profilin-1 (PFN1) and thymosin beta-4 (TMSB4X), were absolutely quantified using 15 N-labeled recombinant proteins spiked externally. The other 13 proteins were quantified in a relative way compared with the two reference proteins. Triplicated LC-MRM-MS measurements showed that the median CV of MRM peak areas was 5.7%. The amounts of PFN1 and TMSB4X increased rapidly depending on the storage time between blood collection and plasma preparation. It indicates the leakage of cellular components into the plasma fraction. Relative quantification further revealed that five proteins including PFN1, S10A8, S10A9, S10A11, and TMSB4X showed significant difference (P < 0.05). We further monitored PFN1 and TMSB4X on 40 samples collected for protein diagnostics under a typical clinical study condition. Compared with the plasma samples prepared within a day, the level of both PFN1 and TMSB4X increased in the plasma samples prepared from the blood collected the day before and kept overnight at 4°C (0.51 to 3.11 µg/mL for PFN1 and 0.98 to 5.36 µg/mL for TMSB4X in average). Our result suggests an effort of assuring plasma quality for accurate protein-based diagnosis or biomarker discovery and validation.

Sources of variability in quantifying circulating thymosin beta-4: literature review and recommendations.

INTRODUCTION: Thymosin beta-4 (TB4) is an endogenous peptide with protective and regenerative effects in models of cellular and organ injury. TB4 is increasingly measured as a potential plasma or serum biomarker in human cardiovascular, liver, infectious, and autoimmune disease. AREAS COVERED: The focus of this review is the quantification of TB4 in clinical cohort studies and whether reported TB4 concentrations differ with respect to method of sample preparation. We survey current literature for studies measuring TB4 in human serum or plasma and compare reported concentrations in healthy controls. EXPERT OPINION: We find substantial intra- and inter- study variability in healthy controls, and a lack of protocol standardization. We further highlight three factors that may confound TB4 clinical measurements and should be considered in future study design: 1) residual platelets remaining in suspension after centrifugation, 2) TB4 release following ex vivo platelet activation, and 3) specificity of assays towards posttranslational modifications. Accordingly, we put forth our recommendations to minimize residual and activated platelets during sample collection, and to cross-validate TB4 measurements using both antibody-based and mass spectrometry-based methods.

Serum thymosin beta4 as a noninvasive biomarker in patients with nonalcoholic steatohepatitis.

OBJECTIVE: The aim of the study was to determine whether serum thymosin beta4 (Tß4) can be a useful noninvasive biomarker to differentiate between nonalcoholic steatohepatitis (NASH) and nonalcoholic fatty liver (NAFL). METHODS: The study included 24 NAFL patients and 21 NASH patients. The levels of Tß4, 8-hydroxydeoxyguanosine acid (8-OhdG), liver function parameters, blood lipid, and glucose were detected in the venous blood of all patients. The NAFLD histological activity score (NAS) was examined in biopsy specimens from all patients. Statistical analysis was performed in order to find differences between the two abovementioned groups. In addition, receiver operator characteristic (ROC) analyses for alanine aminotransferase (ALT) and Tß4 levels were performed in NAFL and NASH patients and the cut-off value was determined. Associations between the variables were tested using correlation coefficient calculations. Statistical significance was set at a p value of < 0.05. RESULTS: Serum Tß4 content was 5.12 ± 1.87 mg/l in the NAFL group and 2.98 ± 1.35 mg/l in the NASH group (p < 0.001). Serum Tß4 content and NAS, histological features of hepatic steatosis, lobular inflammation and ballooning, ALT, glucose and 8-OhdG levels were negatively correlated (p < 0.05 for all) in the NASH group. The correlation coefficient values were -0.530, -0.562, -0.574, -0.438, -0.446, -0.426 and -0.563, respectively. On the basis of ROC analysis, the best predictive Tß4 cut-off value for detecting NASH was 3.94 mg/l (85.7% sensitivity and 79.2% specificity, which were higher than those of ALT). CONCLUSION: Serum Tß4 level can be used as a biomarker for the diagnosis of NASH and was negatively correlated with the oxidation state of the liver.

Thymosin Beta-4 Is Elevated in Women With Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Thymosin beta-4 (TB4) is an X-linked gene product with cardioprotective properties. Little is known about plasma concentration of TB4 in heart failure (HF), and its relationship with other cardiovascular biomarkers. We sought to evaluate circulating TB4 in HF patients with preserved (HFpEF) or reduced (HFrEF) ejection fraction compared to non-HF controls. METHODS AND RESULTS: TB4 was measured using a liquid chromatography and mass spectrometry assay in age- and sex-matched HFpEF (n=219), HFrEF (n=219) patients, and controls (n=219) from a prospective nationwide study. Additionally, a 92-marker multiplex proximity extension assay was measured to identify biomarker covariates. Compared with controls, plasma TB4 was elevated in HFpEF (985 [421-1723] ng/mL versus 1401 [720-2379] ng/mL, P<0.001), but not in HFrEF (1106 [556-1955] ng/mL, P=0.642). Stratifying by sex, only women (1623 [1040-2625] ng/mL versus 942 [386-1891] ng/mL, P<0.001), but not men (1238.5 [586-1967] ng/mL versus 1004 [451-1538] ng/mL, P=1.0), had significantly elevated TB4 in the setting of HFpEF. Adjusted for New York Heart Association class, N-terminal pro B-type natriuretic peptide, age, and myocardial infarction, hazard ratio to all-cause mortality is significantly higher in women with elevated TB4 (1.668, P=0.036), but not in men (0.791, P=0.456) with HF. TB4 is strongly correlated with a cluster of 7 markers from the proximity extension assay panel, which are either X-linked, regulated by sex hormones, or involved with NF-κB signaling. CONCLUSIONS: We show that plasma TB4 is elevated in women with HFpEF and has prognostic information. Because TB4 can preserve EF in animal studies of cardiac injury, the relation of endogenous, circulating TB4 to X chromosome biology and differential outcomes in female heart disease warrants further study.

A fragment of the alarmin prothymosin α as a novel biomarker in murine models of bacteria-induced sepsis.

Sepsis is a life-threatening condition that requires urgent care. Thus, the identification of specific and sensitive biomarkers for its early diagnosis and management are of clinical importance. The alarmin prothymosin alpha (proTα) and its decapeptide proTα(100-109) are immunostimulatory peptides related to cell death. In this study, we generated bacterial models of sepsis in mice using two Klebsiella pneumoniae strains (L-78 and ATCC 43816) and monitored sepsis progression using proTα(100-109) as a biomarker. Serum concentration of proTα(100-109) gradually increased as sepsis progressed in mice infected with L-78, a strain which, unlike ATCC 43816, was phagocytosed by monocytes/macrophages. Analysis of splenocytes from L-78-infected animals revealed that post-infection spleen monocytes/macrophages were gradually driven to caspase-3-mediated apoptosis. These results were verified in vitro in L-78-infected human monocytes/macrophages. Efficient phagocytosis of L-78 by monocytes stimulated their apoptosis and the concentration of proTα(100-109) in culture supernatants increased. Human macrophages strongly phagocytosed L-78, but resisted cell death. This is the first report suggesting that high levels of proTα(100-109) correlate, both in vitro and in vivo, with increased percentages of cell apoptosis. Moreover, we showed that low levels of proTα(100-109) early post-infection likely correlate with sepsis resolution and thus, the decapeptide could eventually serve as an early surrogate biomarker for predicting bacteria-induced sepsis outcome.

Thymosin beta 10 is a key regulator of tumorigenesis and metastasis and a novel serum marker in breast cancer.

BACKGROUND: Thymosin beta 10 (TMSB10) has been demonstrated to be involved in the malignant process of many cancers. The purpose of this study was to determine the biological roles and clinical significance of TMSB10 in breast cancer and to identify whether TMSB10 might be used as a serum marker for the diagnosis of breast cancer. METHODS: TMSB10 expression was evaluated by immunohistochemical analysis (IHC) of 253 breast tumors and ELISA of serum from 80 patients with breast cancer. Statistical analysis was performed to explore the correlation between TMSB10 expression and clinicopathological features in breast cancer. Univariate and multivariate Cox regression analysis were performed to examine the association between TMSB10 expression and overall survival and metastatic status. In vitro and in vivo assays were performed to assess the biological roles of TMSB10 in breast cancer. Western blotting and luciferase assays were examined to identify the underlying pathway involved in the tumor-promoting role of TMSB10. RESULTS: We found TMSB10 was upregulated in breast cancer cells and tissues. Univariate and multivariate analysis demonstrated that high TMSB10 expression significantly correlated with clinicopathological features, poor prognosis and distant metastases in patients with breast cancer. Overexpression of TMSB10 promotes, while silencing of TMSB10 inhibits, proliferation, invasion and migration of breast cancer cells in vitro and in vivo. Our results further reveal that TMSB10 promotes the proliferation, invasion and migration of breast cancer cells via AKT/FOXO signaling, which is antagonized by the AKT kinase inhibitor perifosine. Importantly, the expression of TMSB10 is significantly elevated in the serum of patients with breast cancer and is positively associated with clinical stages of breast cancer. CONCLUSION: TMSB10 may hold promise as a minimally invasive serum cancer biomarker for the diagnosis of breast cancer and a potential therapeutic target which will facilitate the development of a novel therapeutic strategy against breast cancer.

Serum thymosin α 1 levels in patients with chronic inflammatory autoimmune diseases.

Thymosin alpha 1 (Tα1) is a powerful modulator of immunity and inflammation. Despite years of studies, there are a few reports evaluating serum Tα1 in health and disease. We studied a cohort of healthy individuals in comparison with patients affected by chronic inflammatory autoimmune diseases. Sera from 120 blood donors (healthy controls, HC), 120 patients with psoriatic arthritis (PsA), 40 with rheumatoid arthritis (RA) and 40 with systemic lupus erythematosus (SLE), attending the Transfusion Medicine or the Rheumatology Clinic at the Policlinico Tor Vergata, Rome, Italy, were tested for Tα1 content by means of a commercial enzyme-linked immunosorbent assay (ELISA) kit. Data were analysed in relation to demographic and clinical characteristics of patients and controls. A gender difference was found in the HC group, where females had lower serum Tα1 levels than males (P < 0·0001). Patients had lower serum Tα1 levels than HC (P < 0·0001), the lowest were observed in PsA group (P < 0·0001 versus all the other groups). Among all patients, those who at the time of blood collection were taking disease-modifying anti-rheumatic drugs (DMARD) plus steroids had significantly higher Tα1 levels than those taking DMARD alone (P = 0·044) or no treatment (P < 0·0001), but not of those taking steroids alone (P = 0·280). However, whichever type of treatment was taken by the patients, serum Tα1 was still significantly lower than in HC and there was no treatment-related difference in PsA group. Further prospective studies are necessary to confirm and deepen these observations. They might improve our understanding on the regulatory role of Tα1 in health and disease and increase our knowledge of the pathogenesis of chronic inflammatory autoimmune diseases.

Serum Thymosin ß4 Concentrations in Obstructive Sleep Apnea Syndrome Patients.

OBJECTIVE: Inflammation is a potential mechanism of obstructive sleep apnea syndrome (OSAS). Thymosin ß4, a member of thymic protein family, exhibits an anti-inflammatory effect. We determine to investigate whether serum thymosin ß4 concentrations is correlated with the occurrence and disease severity of OSAS. METHODS: Serum thymosin ß4 concentrations were examined in a cross-sectional population including 158 patients with OSAS and 94 healthy subjects. RESULTS: Elevated serum thymosin ß4 concentrations were found in OSAS patients than the controls. Multivariable logistic regression analysis indicated a significant association between serum thymosin ß4 concentrations and OSAS development. Severe OSAS patients showed increased serum thymosin ß4 concentrations compared with mild and moderate patients. Spearman correlation analysis suggested that serum thymosin ß4 concentrations were correlated with the severity of OSAS. Simple linear regression analyses showed that serum thymosin ß4 in OSAS patients was correlated with homeostasis model assessment of insulin resistance, apnea hypopnea index, disease severity, and osteoarthritis development. Then multiple stepwise regression analysis showed that only disease severity remained to be associated with serum thymosin ß4. CONCLUSIONS: Serum thymosin ß4 concentrations were correlated with the occurrence and severity of OSAS.

Plasma levels of F-actin and F:G-actin ratio as potential new biomarkers in patients with septic shock.

OBJECTIVE: To compare plasma levels of F-actin, G-actin and thymosin beta 4 (TB4) in humans with septic shock, noninfectious systemic inflammatory response syndrome (SIRS) and healthy controls. RESULTS: F-actin was significantly elevated in septic shock as compared with noninfectious SIRS and healthy controls. G-actin levels were greatest in the noninfectious SIRS group but significantly elevated in septic shock as compared with healthy controls. TB4 was not detectable in the septic shock or noninfectious SIRS group above the assay's lowest detection range (78 ng/ml). CONCLUSIONS: F-actin is significantly elevated in patients with septic shock as compared with noninfectious SIRS. F-actin and the F:G-actin ratio are potential biomarkers for the diagnosis of septic shock.

Increases in plasma Tß4 after intracardiac cell therapy in chronic ischemic heart failure is associated with symptomatic improvement.

AIM: Tß4 is an integral factor in repair of myocardium in animal models. To investigate whether Tß4 is important in human cardiac disease and has a role in mediating the beneficial cardiac effects of bone-marrow-derived stem cell (BMSC) therapy, we measured serial plasma Tß4 levels in patients enrolled on the REGENERATE-IHD cell therapy trial. PATIENTS & METHODS: Plasma Tß4 concentrations were measured in 13 patients who received BMSCs and 14 controls. RESULTS: There was a significant increase in plasma Tß4 in the BMSC group 24 h after intracardiac injection. Increases in Tß4 levels were associated with improvement in New York Heart Association symptom class. CONCLUSION: This exploratory study highlights the need for further study of Tß4 in human cardiovascular disease.

Thymosinß4: a novel assessed biomarker of the prognosis of acute-on-chronic liver failure patient?

BACKGROUND AND AIM: In the previous study, we found serum thymosin ß4 (Tß4) levels were associated with mortality in liver failure patients. In this study, we try to evaluate the prognostic value of Tß4 in acute-on-chronic liver failure (AoCLF) patients by comparing with the Child-Pugh (CTP) and Model for End-Stage Liver Disease (MELD) scores. METHODS: Serum Tß4 levels were measured by enzyme-linked immunosorbent assay (ELISA), and the CTP and MELD scores were calculated for each patient. RESULTS: Serum Tß4 levels of AoCLF patients [0.4120 (0.2447-0.7492)µg/mL] were lower than healthy controls [9.2710 (5.1660-13.2485)µg/mL] (P<0.001). AoCLF patients were divided into survival and death group. Compared to survivors, lower Tß4 concentrations, higher CTP and MELD scores (P<0.001, respectively) were observed in AoCLF patients who died. There were negative correlations between Tß4 levels and CTP scores (P<0.001), MELD scores (P<0.001). A CTP score of 11.5, a MELD score of 21.63 and a Tß4 concentration of 0.3840µg/mL were identified as the cut-off values for the stratification of AoCLF patients. MELD≥21.63 combined with Tß4<0.3840µg/mL can more exactly discriminate between the patients who would survive and die. CONCLUSIONS: Serum Tß4 concentration has appreciable value to evaluate the short-term prognosis of AoCLF patients, although Tß4 is not superior to MELD. The combination of Tß4 and MELD scores are more effective in assessing the prognosis of AoCLF patients.

Increased thymosin ß4 levels in the serum and SF of knee osteoarthritis patients correlate with disease severity.

OBJECTIVE: Thymosin ß4, a member of a large family of thymic proteins, plays an important role in the process of articular cartilage degeneration which is a common cause of osteoarthritis (OA). This study aims to determine thymosin ß4 levels in the serum and synovial fluid (SF) of patients with knee OA and analyze the correlation of thymosin ß4 levels with the radiographic severity of OA. METHODS: This study consisted of 216 patients with knee OA and 152 healthy controls. OA progression was classified based on Kellgren-Lawrence by evaluating x-ray changes observed in anteroposterior knee radiography. Thymosin ß4 levels in the serum and SF were measured by enzyme-linked immunosorbent assay method. RESULTS: The knee OA patients had higher levels of serum thymosin ß4 than the healthy controls. Knee OA patients with KL grade 4 showed significantly elevated thymosin ß4 levels in the serum and SF compared with those with KL grades 2 and 3. Knee OA patients with KL grade 3 had significantly higher SF levels of thymosin ß4 than those with KL grade 2. Thymosin ß4 levels in the serum and SF of knee OA patients were significantly correlated with disease severity according to KL grading criteria. CONCLUSION: The thymosin ß4 levels in the serum and SF may serve as effective biomarkers for the severity of OA.

Development of an ELISA for the quantification of the C-terminal decapeptide prothymosin α(100-109) in sera of mice infected with bacteria.

Apoptosis is characterized by a series of discrete biochemical events, among which is the truncation of the nuclear polypeptide prothymosin alpha (proTα) by activated caspase-3. This early apoptotic event results in the generation of a carboxy-terminal fragment of proTα, the immunoactive decapeptide proTα(100-109). We hypothesized that the detection of increased levels of proTα(100-109) in serum can be directly correlated with the induction of massive cell apoptosis, resulting from a severe bacterial infection. Thus, using high-affinity-purified polyclonal antibodies (Abs), raised in rabbits and a prototype antibody-capture system, we developed a highly sensitive and specific competitive ELISA for proTα(100-109). The sensitivity of the ELISA (0.1ng/mL to 10µg/mL) is acceptable for the quantification of the decapeptide in serum samples. To assess our initial hypothesis, we determined the concentration of proTα(100-109) in the sera of mice infected with the bacterium Streptococcus pyogenes over the course of the infection. We show that serum concentration of proTα(100-109) was marginal to undetectable before infection, increased over time and peaked at 72h postinfection. In silico analysis suggests that the Abs generated are unlikely to cross-react with any other unrelated mouse or bacterial protein. Further validation of our ELISA using serum samples from humans, infected with bacteria, may provide a useful tool to differentiate the causative agent of a potentially lethal septic infection.

Identification of tubulin beta chain, thymosin beta-4-like protein 3, and cytochrome b-c1 complex subunit 1 as serological diagnostic biomarkers of gastric cancer.

OBJECTIVE: Despite major advances in its diagnosis and treatment, gastric cancer (GC) remains a major life-threatening disease. Treatment of the disease is further aggravated by the lack of diagnostic biomarkers that can aid in the early detection of GC and promote its favorable prognosis. The present work aims to identify novel diagnostic biomarkers for GC. DESIGN AND METHODS: The present work is a case-control study that focuses on proteomic analysis of serum from healthy volunteers and GC patients using ClinProt profiling technology based on mass spectrometry. A pattern of proteins/peptides with the ability to differentiate the studied populations was identified. Deregulated proteins/peptides differentially expressed in the serum of patients compared with healthy volunteers were identified by mass spectroscopy. RESULTS: A pattern of proteins/peptides consisting of four protein/peptide peaks at m/z 1467, 1867, 2701, and 2094 was identified. These protein/peptide peaks were able to differentiate the studied populations with close to 100% sensitivity and specificity. Three of the deregulated proteins/peptides at m/z 1867, 2701, and 2094 were identified by mass spectroscopy (LTQ Orbitrap XL) as tubulin beta chain, thymosin beta-4-like protein 3, and cytochrome b-c1 complex subunit 1, respectively. CONCLUSIONS: The pattern of proteins/peptides identified in the present work shows great potential for GC diagnosis. Deregulated proteins of tubulin beta chain, thymosin beta-4-like protein 3, and cytochrome b-c1 complex subunit 1 may be involved in the pathogenesis of GC and serve as potential serological diagnostic biomarkers.

Plasma thymosin-α1 level as a potential biomarker in urothelial and renal cell carcinoma.

OBJECTIVES: To determine the plasma levels of thymosin-α1 (TA1) and prothymosin-α (PTMA) proteins in renal cell carcinoma (RCC) or urothelial carcinoma (UC) patients, and explore the potential of these 2 molecules as biomarkers. MATERIALS AND METHODS: Blood samples were taken from 50 consecutive patients with RCC, 97 with UC, and 55 with benign urologic diseases before surgery. Their clinical characteristics were obtained from medical record review. Plasma TA1 and PTMA levels were measured using enzyme-linked immunosorbent assay and their correlation with tumor grade, pathologic stage, and survival were explored. RESULTS: Plasma TA1 levels were significantly lower in RCC patients than in UC or benign patients, particularly in UC of the renal pelvis patients (P < 0.0001). Plasma PTMA levels were also significantly lower in UC patients compared with RCC patients and benign patients (P < 0.05). Plasma TA1 levels inversely correlated with pathologic stage both in bladder cancer and RCC patients (P = 0.03 and 0.02, respectively). Both plasma TA1 and PTMA did not correlate with tumor grade. Plasma TA1 was a prognostic indicator for progression-free and disease-specific overall survival in bladder cancer patients (P = 0.008 and 0.04, respectively). CONCLUSIONS: Plasma TA1 level may be a biomarker for differentiating between UC and RCC. It may also be a prognostic factor for disease progression and disease-specific survival in bladder cancer patients. These findings warrant more studies for validation.