Foxp3+CD39+CD73+ regulatory T-cells are decreased in the peripheral blood of women with deep infiltrating endometriosis.

Endometriosis's pathophysiology remains incompletely understood, with evidence pointing towards a dysregulated immune response. Regulatory T (Treg) cells, pivotal in maintaining self-tolerance, may facilitate the survival of ectopic endometrial cells within the abdominal cavity, thereby contributing to endometriosis development. This study aimed to assess the prevalence of CD39+CD73+ suppressor Treg cell subsets in the peripheral blood of endometriosis patients. This research focuses on the pivotal role of regulatory T-cells (Tregs), which are essential for maintaining immune tolerance and preventing autoimmune diseases. A case-control study was conducted, including 32 women diagnosed with endometriosis and 22 control subjects. The frequency of peripheral blood CD39+CD73+ suppressor Treg cells was quantified using flow cytometry. No significant differences were observed in the frequency of CD3+CD4+CD25High cells (Median [M]: 10.1; Interquartile Range [IQR]: 6.32‒18.3 vs. M: 9.72; IQR: 6.22-19.8) or CD3+CD4+CD25HighCD39+Foxp3+ cells (M: 31.1; IQR: 19.7-44.0 vs. M: 30.55; IQR: 18.5-45.5) between controls and patients. However, a significantly lower frequency of CD3+CD4+CD25HighCD39+CD73+ cells was observed in the endometriosis group compared to controls (M: 1.98; IQR: 0.0377-3.17 vs. M: 2.25; IQR: 0.50-4.08; p = 0.0483), suggesting a reduction in systemic immune tolerance among these patients. This finding highlights the potential role of CD39 and CD73 expression on Treg cells as biomarkers for assessing disease severity and progression. Furthermore, elucidating the mechanisms driving these alterations may unveil new therapeutic strategies to restore immune equilibrium and mitigate endometriosis symptoms.

Plasma-derived candidate biomarkers for detection of gallbladder carcinoma.

Gallbladder carcinoma (GBC) is a major cancer of the gastrointestinal tract with poor prognosis. Reliable and affordable biomarker-based assays with high sensitivity and specificity for the detection of this cancer are a clinical need. With the aim of studying the potential of the plasma-derived extracellular vesicles (EVs), we carried out quantitative proteomic analysis of the EV proteins, using three types of controls and various stages of the disease, which led to the identification of 86 proteins with altered abundance. These include 29 proteins unique to early stage, 44 unique to the advanced stage and 13 proteins being common to both the stages. Many proteins are functionally relevant to the tumor condition or have been also known to be differentially expressed in GBC tissues. Several of them are also present in the plasma in free state. Clinical verification of three tumor-associated proteins with elevated levels in comparison to all the three control types-5'-nucleotidase isoform 2 (NT5E), aminopeptidase N (ANPEP) and neprilysin (MME) was carried out using individual plasma samples from early or advanced stage GBC. Sensitivity and specificity assessment based on receiver operating characteristic (ROC) analysis indicated a significant association of NT5E and ANPEP with advanced stage GBC and MME with early stage GBC. These and other proteins identified in the study may be potentially useful for developing new diagnostics for GBC.

Effect of Maternal Marginal Zinc Deficiency on Development, Redox Status, and Gene Expression Related to Oxidation and Apoptosis in an Avian Embryo Model.

Maternal severe zinc (Zn) deficiency resulted in growth retardation and high mortality during embryonic development in human. Therefore, this study is aimed at evaluating the effect of maternal marginal Zn deficiency on the development and redox status to avoid severe Zn deficiency using an avian model. A total of 324 laying duck breeders at 214 days old were randomly allotted into 3 dietary Zn levels with 6 replicates of 18 ducks per replicate. The birds were fed experimental diets including 3 dietary supplemental Zn levels of 0 mg/kg (maternal Zn-deficient group, 29.2 mg Zn/kg diet), 60 mg/kg (maternal Zn-adequate group), and 120 mg/kg (maternal Zn-high group) for 6 weeks. Dietary Zn levels had on effect on egg production and fertility (P > 0.05), whereas dietary Zn deficiency decreased breeder plasma Zn concentration and erythrocytic alkaline phosphatase activity at week 6 and inhibited erythrocytic 5'-nucleotidase (5'-NT) activity at weeks 2, 4, and 6 (P < 0.05), indicating that marginal Zn-deficient status occurred after Zn depletion. Maternal marginal Zn deficiency increased embryonic mortality and contents of superoxide anion radical, MDA, and PPC and reduced MT content and CuZnSOD activity in duck embryonic livers on E29. The MDA content was positively correlated with embryonic mortality. Maternal marginal Zn deficiency increased BCL2-associated X protein and Caspase-9 mRNA expressions as well as decreased B-cell lymphoma-2 and MT1 mRNA and signal AKT1 and ERK1 protein expressions (P < 0.05). Breeder plasma Zn concentration and erythrocytic 5'-NT activities at week 6 were positively correlated with GSH-Px activity and GPx, MT1, and BCL2 mRNA expressions in embryonic livers on E29. In conclusion, erythrocytic 5'-NT activity could be more rapid and reliable to monitor marginal Zn-deficient status. Marginal Zn deficiency impaired hatchability and antioxidant defense system and then induced oxidative damage and apoptosis in the embryonic liver, contributing to the greater loss of duck embryonic death.

AMP hydrolysis reduction in blood plasma of breast cancer elderly patients after different treatments.

Adenine nucleotides are important signaling molecules that mediate biological functions in many conditions, including cancer. The enzymes CD39 and CD73 produce adenosine in the extracellular milieu that has a very important role in tumor development. This study aimed to evaluate nucleotide hydrolysis in the plasma blood of breast cancer elderly patients. In this prospective cohort study, we investigated the ectonucleotidases activity in breast cancer elderly patients, at the moment of diagnosis and after treatment. Control group consisted of elderly women without cancer diagnostic. The nucleotide hydrolysis assay was performed by the malachite green method and used ATP, ADP, or AMP as substrates. Paired t test or Wilcoxon rank-sum test was used. Our data showed that breast cancer patients presented high levels of ATP and AMP hydrolyses when compared to control group at the moment of diagnosis. When analyzing the differences between the samples at the time of diagnostic and 6 months after treatment, we observed a significant reduction on CD73 activity after all treatments used: surgery, chemotherapy, radiotherapy, or hormone therapy. The results with APCP, a specific CD73 inhibitor, showed that the AMP hydrolysis was inhibited in all conditions evaluated. We observed a diminished ADPase activity in the patients without metastasis when compared to metastatic breast cancer patients. The results showed that AMP hydrolysis was reduced in the blood plasma of breast cancer elderly patients after different treatments. This study strengthens the potential role of CD73 enzyme as a biomarker for breast cancer treatment response.

CD73 Maintains Hepatocyte Metabolic Integrity and Mouse Liver Homeostasis in a Sex-Dependent Manner.

BACKGROUND & AIMS: Metabolic imbalance and inflammation are common features of chronic liver diseases. Molecular factors controlling these mechanisms represent potential therapeutic targets. CD73 is the major enzyme that dephosphorylates extracellular adenosine monophosphate (AMP) to form the anti-inflammatory adenosine. CD73 is expressed on pericentral hepatocytes, which are important for long-term liver homeostasis. We aimed to determine if CD73 has nonredundant hepatoprotective functions. METHODS: Liver-specific CD73 knockout (CD73-LKO) mice were generated by targeting the Nt5e gene in hepatocytes. The CD73-LKO mice and hepatocytes were characterized using multiple approaches. RESULTS: Deletion of hepatocyte Nt5e resulted in an approximately 70% reduction in total liver CD73 protein (P < .0001). Male and female CD73-LKO mice developed normally during the first 21 weeks without significant liver phenotypes. Between 21 and 42 weeks, the CD73-LKO mice developed spontaneous-onset liver disease, with significant severity in male mice. Middle-aged male CD73-LKO mice showed hepatocyte swelling and ballooning (P < .05), inflammation (P < .01), and variable steatosis. Female CD73-LKO mice had lower serum albumin levels (P < .05) and increased inflammatory genes (P < .01), but did not show the spectrum of histopathologic changes in male mice, potentially owing to compensatory induction of adenosine receptors. Serum analysis and proteomic profiling of hepatocytes from male CD73-LKO mice showed significant metabolic imbalance, with increased blood urea nitrogen (P < .0001) and impairments in major metabolic pathways, including oxidative phosphorylation and AMP-activated protein kinase (AMPK) signaling. There was significant hypophosphorylation of AMPK substrates in CD73-LKO livers (P < .0001), while in isolated hepatocytes treated with AMP, soluble CD73 induced AMPK activation (P < .001). CONCLUSIONS: Hepatocyte CD73 supports long-term metabolic liver homeostasis through AMPK in a sex-dependent manner. These findings have implications for human liver diseases marked by CD73 dysregulation.

Serum CD73 is a prognostic factor in patients with metastatic melanoma and is associated with response to anti-PD-1 therapy.

BACKGROUND: Inhibitors of immune checkpoint programmed cell death protein 1 (PD-1) receptor on T cells have shown remarkable clinical outcomes in metastatic melanoma. However, most patients are resistant to therapy. Production of extracellular adenosine, via CD73-mediated catabolism of AMP, contributes to suppress T-cell-mediated responses against cancer. In this study, we analyzed the expression and activity of soluble CD73 in sera of patients with melanoma undergoing anti-PD-1± cytotoxic T-lymphocyte-associated antigen 4 therapy. METHODS: Soluble CD73 expression and activity were retrospectively analyzed in serum of a total of 546 patients with melanoma from different centers before starting treatment (baseline) with anti-PD-1 agents, nivolumab or pembrolizumab, and compared with those of 96 healthy subjects. The CD73 activity was correlated with therapy response and survival of patients. RESULTS: Patients with melanoma show significantly higher CD73 activity and expression than those observed in healthy donors (p<0.0001). Elevated pretreatment levels of CD73 activity were associated with non-response to therapy with nivolumab or pembrolizumab. During treatment, levels of soluble CD73 activity remain unchanged from baseline and still stratify clinical responders from non-responders. High levels of serum CD73 enzymatic activity associate with reduced overall survival (OS; HR=1.36, 95% CI 1.03 to 1.78; p=0.03) as well as progression-free survival (PFS; HR=1.42, 95% CI 1.13 to 1.79, p=0.003). Further, the multivariate Cox regression analysis indicates that serum CD73 activity is an independent prognostic factor besides serum lactate dehydrogenase levels and the presence of brain metastases for both OS (p=0.009) and PFS (p=0.001). CONCLUSION: Our data indicate the relevance of serum CD73 in patients with advanced melanoma receiving anti-PD-1 therapy and support further investigation on targeting CD73 in combination with anti-PD-1 antibodies.

NMR-Based Assay for the Ex Vivo Determination of Soluble CD73 Activity in Serum.

Extracellular adenosine, produced through the activity of ecto-5'-nucleotidase CD73, elicits potent immunosuppressive effects, and its upregulation in tumor cells as well as in stromal and immune cell subsets within the tumor microenvironment is hypothesized to represent an important resistance mechanism to current cancer immunotherapies. Soluble CD73 (sCD73) enzymatic activity measured in patient serum or plasma at a baseline is reported to have prognostic as well as predictive relevance, with higher sCD73 activity associating with poor overall and progression-free survival in melanoma patients undergoing anti-PD1 monoclonal antibody treatment. Here, we report a novel NMR-based method that measures the ex-vivo kinetics of sCD73 activity with high specificity and reproducibility and is suitable for future high-throughput implementation. Unlike the existing assays, this method has the advantage of directly and simultaneously measuring the concentration of both the CD73 substrate and product with minimal sample manipulation or special reagents. We establish the utility of the assay for measuring the activity of sCD73 in human serum and show a strong linear correlation between sCD73 protein levels and enzyme activity. Together with our finding that sCD73 appears to be the predominant activity for the generation of adenosine in human blood, our results demonstrate a link between activity and protein levels that will inform future clinical application.

Positive Cytosolic 5-Nucleotidase 1A Antibodies in Motor Neuron Disease.

Inclusion body myositis (IBM) is the most common acquired myopathy in adults older than 50 years. Muscle biopsy remains the gold standard for diagnosis. Recently described serum antibodies against cytosolic 5-nucleotidase 1A (cN1A) are considered highly specific for IBM. However, positive cN1A antibodies in diseases other than IBM are recently reported. We review 2 cases in which serum antibodies were positive but ancillary testing revealed motor neuron disease. A 68-year-old man presented with asymmetric quadriceps and handgrip weakness prompting concern for IBM. However, electromyography showed purely chronic neurogenic abnormalities, and muscle biopsy was consistent with post-polio syndrome. A 60-year-old woman reported a history of progressive muscle weakness. Despite positive antibodies, examination and electromyography were indicative of amyotrophic lateral sclerosis. Serum cN1A antibodies are not 100% specific for the diagnosis of IBM. Careful clinical, electrophysiologic, and histopathologic correlation is required in workup of individuals with neuromuscular weakness and positive antibodies.

Intravenous Administration is the Best Route of Mesenchymal Stem Cells Migration in Improving Liver Function Enzyme of Acute Liver Failure.

BACKGROUND: Mesenchymal stem cells (MSCs) migrate and transmigrate to acute liver failure (ALF) area due to vascular endothelial growth factor (VEGF) stimulation as an attractant molecule then actively giving the paracrine signaling and or differentiating into primary hepatocytes, however the best route of MSCs transplanted to liver injury area remains unclear. AIM: In this study we compare intravenous (IV) and intraperitoneal (IP) route of MSCs administration by analyzing serum glutamic pyruvic transaminase (SGPT), serum glutamic-oxaloacetic transaminase (SGOT) and bilirubin level as improvement markers of liver function and VEGF as attractant-proliferation molecule on days 2 and 5. MATERIALS AND METHODS: Eighteen male Sprague-Dawley rats weighting 200 g were used in this study. They were divided in three study groups: vehicle control, IP and IV groups. The IV group was treated by MSCs at dose 1×106 by lateral tail vein injection and IP group received 1×106 MSCs via IP injection. The level of SGPT, SGOT and bilirubin were measured by an automatic analyzer, the VEGF level using enzyme-linked immunosorbent assay (ELISA), while the CD73 expression was evaluated using immunohistochemistry. RESULTS: This study showed that IV injection of MSCs was more efficient for increasing liver function than IP treatment group that confirmed by the observed significant decrease in SGPT, SGOT and bilirubin level on days 2 and 5 (p<0.001). This effect was most likely mediated by the significant increase of VEGF level (p<0.05) on days 2 and 5. CONCLUSION: Our result conclude that an IV administration of MSCs was more efficacious than the IP administration for liver injury regeneration.

Increased cytokines production and oxidative stress are related with purinergic signaling and cell survival in post-thyroidectomy hypothyroidism.

Thyroid hormones have essential roles in regulation of cellular functions, including the immune system. The purinergic signaling, activated through extracellular nucleotides and nucleosides has also strong implications in immune response regulation. Hypothyroidism may involve effects on the immune and purinergic systems. In view of that, we evaluated cytokines levels, their relation with the expression of purinergic enzymes and the effects of this condition on immune system cells from patients with post-thyroidectomy hypothyroidism. Increased IL6, IL10, IL17 and TNF-α levels as well as an increase in CD73 expression in lymphocytes were observed in patients' blood. Moreover, augmented myeloperoxidase activity, lipid peroxidation and thiolgroup production were observed in post-thyroidectomy hypothyroidism. In addition, proliferation and cell death of lymphocytes were enhanced when exposed to patients' serum. This study demonstrates that hypothyroidism is related to changes in the purinergic system, increased cytokines production and oxidative stress, which interfere in the cell life and signaling.

Enzyme activity of circulating CD73 in human serum.

CD73 is an ectonucleotidase able to catabolize 5'-adenosine monophosphate (AMP) into adenosine at the extracellular level. Extracellular adenosine plays a critical role in regulating many processes under physiological and pathological conditions. In the context of cancer, the expression and activity of CD73, either in tissue and in biological fluids, is increased leading to high levels of adenosine that potently suppress T-cell mediated responses, promoting tumor progression through stimulation of adenosine receptors. Compelling evidence indicates that elevated levels of CD73-generating adenosine limit the efficacy of cancer immunotherapy. Inhibitors of ectonucleotidases and antagonists of adenosine receptors have emerged as new therapeutic tools to improve anti-tumor immune response and potentially synergize with currently used immunotherapeutic agents. Measurement of CD73 levels in serum of cancer patients is a promising approach that, although it needs to be validated, may help to select patients who will benefit from adenosine-targeting agents and predict response to immunotherapy. Here, we describe a simple and fast method to evaluate the AMPase activity of CD73 in peripheral blood that may also be applied to other biological fluids.

Expression and clinical significance of serum NT5E protein in patients with colorectal cancer.

OBJECTIVE: This study aimed to investigate the expression level and clinical significance of serum NT5E protein (ecto-5'-nucleotidase) in patients with colorectal cancer. METHODS: The expression level of serum NT5E protein in 232 patients with colorectal cancer and 158 normal controls was detected using enzyme-linked immunosorbent assay. Moreover, the relationship between the expression level of serum NT5E and the clinicopathological features of colorectal cancer was analyzed. RESULTS: The expression level of serum NT5E in patients with colorectal cancer was significantly higher compared with that in normal controls (P< 0.05). The expression level of serum NT5E in patients with colorectal cancer closely correlated with the family history of tumors (P= 0.001), expression level of CA19-9 (P= 0.031), lymph node metastasis (P= 0.001), distant metastasis (P= 0.010), nerve invasion (P= 0.049), degree of differentiation (P= 0.013), and TNM staging (P= 0.001), but not with gender, age, smoking and drinking histories, expression level of carcinoembryonic antigen (CEA), tumor locations, vascular tumor thrombus, cancer nodules, and pathological type (P> 0.05). Moreover, the overall survival rate of patients with colorectal cancer was significantly lower in the NT5E high-expression group, with statistical significance (χ2= 11.184, P= 0.001). CONCLUSIONS: The expression level of serum NT5E increased in patients with colorectal cancer, and closely correlated with the malignant evolution and clinical prognosis of colorectal cancer. NT5E might serve as a serological indicator for molecular diagnosis and prognosis of colorectal cancer clinically.

Phase II trial of nintedanib in patients with bevacizumab-resistant recurrent epithelial ovarian, tubal, and peritoneal cancer.

BACKGROUND: Bevacizumab provides benefit in epithelial ovarian cancer (EOC), yet resistance to bevacizumab often occurs. We determined if nintedanib, a tyrosine kinase inhibitor of VEGF, FGF, and PDGF receptors has antitumor activity in bevacizumab-resistant recurrent EOC, tubal, and peritoneal cancer. METHODS: This phase II study evaluated nintedanib 200 mg/day until disease progression or unacceptable toxicity. The primary objective was 6-month progression free survival (PFS6m). Secondary objectives were response rate and toxicity. Simon two-stage optimal design was used. Baseline angiogenic plasma biomarkers were measured. RESULTS: 27 patients were enrolled evaluable for PFS; 26 were evaluable for PFS6m. The median age was 65 years (range 44-73); 89.9% had high-grade serous EOC; 70% received at least >2 prior chemotherapies; and 81% (22/27) had chemoresistant disease. With median follow up of 15.6 months (range 2-38) the PFS6m rate was 11.5% (3/26). Three participants had long duration of disease control (8-16 months). Median PFS and overall survival were 1.8 and 16 months, respectively. Response rate was 7.4% (2/27 PR). Thirty-seven percent (10/27) had stable disease, while 56% (15/27) had progressive disease. Adverse events included Grade 3 liver enzyme elevation (15%), Grade 3 diarrhea (7%), Grade 2 fatigue (7%), and Grade 2 nausea/vomiting (15%). PD patients exhibited higher levels of CD73, IL6, and VEGFD (p < 0.05) compared to PR/SD patients. IL6 was associated with worse PFS (p = 0.03). CONCLUSIONS: Single-agent nintedanib has minimal activity in an unselected bevacizumab-resistant EOC population. Nintedanib was tolerable and toxicities were manageable. Plasma CD73, IL6, and VEGFD were identified as prognostic markers for progressive disease, and IL6 was associated with worse PFS confirming similar observations made in patients treated with other anti-angiogenic agents.

Global expression profiling and pathway analysis in two different population groups in relation to high altitude.

High altitude (HA) is associated with number of stresses. Response of these stresses may vary in different populations depending upon altitude, duration of residency, ancestry, geographical variation, lifestyle, and ethnicities. For understanding population variability in transcriptome, array-based global gene expression profiling was performed on extracted RNA of male volunteers of two different lowland population groups, i.e., Indians and Kyrgyz, at baseline and day 7 of HA exposure (3200 m). A total of 97 genes were differentially expressed at basal in Kyrgyz as compared to Indians (82 downregulated and 15 upregulated), and 196 were differentially expressed on day 7 of HA (118 downregulated and 78 upregulated). Ingenuity Pathway Analysis and gene ontology highlighted eIF2 signaling with most significant negative activation z score at basal in Kyrgyz compared to Indians with downregulation of various L- and S-ribosomal proteins indicating marked translational repression. On day 7, cAMP-mediated signaling is most enriched with positive activation z score in Kyrgyz compared to Indians. Plasma cAMP levels were higher in Kyrgyz on day 7 compared to Indians. Extracellular adenosine levels were elevated in both the groups upon HA, but higher in Kyrgyz compared to Indians. Valedictory qRT-PCR showed upregulation of ADORA2B and CD73 along with downregulation of ENTs in Kyrgyz compared to Indians indicating elevated levels of extracellular nucleotides mainly adenosine and activation of extracellular cAMP-adenosine pathway which as per literature triggers endogenous protective mechanisms under stress conditions like hypoxia. Thus, transcriptome changes at HA are population-specific, and it may be necessary to take care while interposing similar results in different populations.

Alteration of Extracellular Nucleotide Metabolism in Pseudoxanthoma Elasticum.

Pseudoxanthoma elasticum (PXE) is a rare genetic condition primarily caused by hepatic ABCC6 transporter dysfunction. Most clinical manifestations of PXE are due to premature calcification of elastic fibers. However, the vascular impact of PXE is pleiotropic and remains ill defined. ABCC6 expression has recently been associated with cellular nucleotide export. We studied the impact of ABCC6 deficiency on blood levels of adenosine triphosphate and related metabolites and on soluble nucleotidase activities in PXE patients and Abcc6-/- mice. In addition, we investigated the expression of genes encoding ectocellular purinergic signaling proteins in mouse liver and aorta. Plasma adenosine triphosphate and pyrophosphate levels were significantly reduced in PXE patients and in Abcc6-/- mice, whereas adenosine concentration was not modified. Moreover, 5'-nucleotidase/CD73 activity was increased in the serum of PXE patients and Abcc6-/- mice. Consistent with alterations of purinergic signaling, the expression of genes involved in purine and phosphate transport/metabolism was dramatically modified in Abcc6-/- mouse aorta, with much less impact on the liver. ABCC6 deficiency causes impaired vascular homeostasis and tissue perfusion. Our findings suggest that these alterations are linked to changes in extracellular nucleotide metabolism that are remote from the liver. This opens new perspectives for the understanding of PXE pathophysiology.

Adenosine Metabolism in COPD: A Study on Adenosine Levels, 5'-Nucleotidase, Adenosine Deaminase and Its Isoenzymes Activity in Serum, Lymphocytes and Erythrocytes.

Adenosine is a signaling molecule which is produced in high concentrations during airway inflammation. Airway inflammation is a characteristic feature of COPD. Therefore, the current study was designed to evaluate the changes in adenosine metabolism in COPD and correlate these changes with severity of the disease. The study was conducted on 50 healthy controls (25 healthy non-smokers and 25 healthy smokers) and 46 COPD patients (21 moderate, 15 severe and 10 very severe). The patients were sub-divided into moderate, severe and very severe categories as per the GOLD spirometric classification. Blood was collected from each subject and serum, lymphocytes and erythrocytes were separated. The adenosine levels and activities of 5'-nucleotidase, adenosine deaminase and its isoenzymes were assessed in serum, lymphocytes and erythrocytes. The data were analyzed statistically. A p value < 0.05 was considered as significant. In healthy smokers and COPD patients the adenosine levels increased. In COPD patients 5'-nucleotidase activity increased significantly in serum, lymphocytes and erythrocytes. The activities of ADA and isoenzymes decreased significantly in serum of healthy smokers and COPD patients, in lymphocytes and erythrocytes of very severe COPD patients and of ADA and ADA2 in lymphocytes and erythrocytes of moderate and severe COPD patients. The FEV1 (% of predicted) showed a significant negative correlation with adenosine levels and 5'-nucleotidase activity in serum, lymphocytes and erythrocytes and significant positive correlation with ADA and isoenzymes activity in serum and lymphocytes of COPD patients. We conclude that the adenosine metabolism changes in COPD. The adenosine levels and 5'-nucleotidase activity increase, and ADA activity decreases with severity of the disease.

Infant cardiopulmonary bypass: CD73 kinetics, association with clinical outcomes, and influence on serum adenosine production capacity.

BackgroundExtracellular adenine nucleotides contribute to ischemia-reperfusion injury following infant cardiopulmonary bypass (CPB), whereas conversion to adenosine may be protective. Alkaline phosphatase (AP), a key enzyme responsible for this conversion, decreases after infant CPB. Indirect evidence suggests that soluble CD73 may simultaneously increase and partially offset this loss of AP. We sought to measure CD73 levels in infants undergoing CPB and determine its association with adenosine production capacity and postoperative support requirements.MethodsA prospective cohort study of infants ≤120 days of age undergoing CPB. CD73 was measured before CPB and during rewarming. Multivariable modeling evaluated the contributions of CD73/AP to adenosine production capacity and postoperative support requirements.ResultsSerum samples from 85 subjects were analyzed. The median CD73 concentration increased following CPB (95.2 vs. 179.8 ng/ml; P<0.0001). Rewarming CD73 was independently inversely associated with vasoactive inotropic support (P<0.005) and length of intensive care unit stay (P<0.005). Combined AP activity and CD73 concentration predicted adenosine production capacity (P<0.0001).ConclusionsSerum CD73 increases following infant CPB. Low rewarming CD73 is independently associated with increased postoperative support requirements. CD73 and AP together predict serum adenosine production capacity and may represent potential therapeutic targets to clear extracellular adenine nucleotides and improve outcomes following infant CPB.

Treatment with tucumã oil (Astrocaryum vulgare) for diabetic mice prevents changes in seric enzymes of the purinergic system: Improvement of immune system.

The aim of this study was to evaluate the enzymatic activity of the purinergic system in sera samples from alloxan-induced diabetic mice treated with tucumã oil (Astrocaryum vulgare). For this, the mice were divided into four groups (n=6): control/water (the group CW); control/tucumã oil (the group CT); diabetic/water (the group DW), and diabetic/tucumã oil (the group DT) treated for 14days with 5.0mLkg-1 via oral gavage. On day 14 post-treatment, mice were submitted to euthanasia and blood samples were collected by cardiac puncture. Tucumã oil treatment significantly decreased (p<0.05) blood glucose levels in the group DT compared to the group DW. These results demonstrated an increase (p<0.05) in NTPDase (adenosine triphosphate (ATP substrate) or adenosine diphosphate (ADP substrate)), 5'-nucleotidase (AMP substrate) and adenosine deaminase (ADA; adenosine substrate) activities in serum from the group DW compared to the group CW. Tucumã oil treatment prevented these alterations in the group DT compared to the group DW, and restored these parameters near to the group CW. In summary, the treatment with tucumã oil was able to modulate the alterations caused by hyperglycemia probably by the presence of carotenoids compounds, maintaining normal levels of ATP, ADP, AMP and adenosine, molecules that could exhibit anti-inflammatory properties, depending on their concentration. Thus, the tucumã oil is a promising natural compound with protective action against diabetes and its side effects, such as changes in the purinergic system, improving the immune system.

Toxoplasmosis treatment with diphenyl diselenide in infected mice modulates the activity of purinergic enzymes and reduces inflammation in spleen.

Toxoplasma gondii, an intracellular protozoan, may cause chronic infection in the brain tissue of the host inducing a systemic pro-inflammatory profile. Chronic infections can induce numerous physiological changes, such as alterations in the immune and oxidative profiles. Diphenyl diselenide (PhSe)2, an organoselenium compound, has shown antioxidant and immunomodulatory activities in recent studies. So, the aim of this study was to investigate the activity of purinergic enzymes and reactive oxygen species (ROS) in serum and spleen of mice chronically infected by T. gondii, untreated and treated with (PhSe)2. For this experiment, were divided into four groups: Group A (healthy mice), Group B (healthy mice treated with (PhSe)2), Group C (infected mice) and Group D (infected mice treated with (PhSe)2). Group C and group D were infected via oral route with ME49 Toxoplasma gondii strain. Groups B and D were treated subcutaneously with 5 µmol kg-1 of (PhSe)2. Chronic T. gondii infection induced splenomegaly and physiological changes in the spleen and raised histologic inflammatory markers, ROS levels and the activity of purinergic enzymes activity such as NTPDase, 5´nucleotidase and ADA. In serum, the infection increased 5´nucleotidase and ADA activities. (PhSe)2per se has managed to decrease ROS levels and ADA activity and increase NTPDase and 5´nucleotidase in spleen. In infected mice, treatment with (PhSe)2 reversed splenomegaly, reduced histological inflammatory markers, ROS levels and ADA activity in the spleen. Our results prove that chronic toxoplasmosis can induce splenomegaly, heightens ROS levels and purinergic enzyme activity in mice. These results suggest that (PhSe)2 is a potential therapy for the alterations found in the spleen in chronic T. gondii infection.

New aspects of the Seam4D-dependent control of lymphocyte activation.

Novel targets for action of the class IV semaphorin Seam4D have been identified in the immune system. The low-affinity CD72 receptor for Seam4D was detected not only on B lymphocytes, but also in a proportion of T cells, whereas the high-affinity semaphorin receptor, plexin B1, originally considered to belong to non-immune cells, proved to be in a great proportion of intact T and B cells. Seam4D is constitutively expressed in B cells, which, along with T cells, can serve as a source of both membrane and soluble semaphorin. The results obtained make significant adjustments in understanding of Seam4D effects in lymphoid cells.