Plasma polyamines during pregnancy and their relationships with maternal allergies and the immune response of the neonates.

BACKGROUND: Some studies have reported that polyamine levels may influence immune system programming. The aim of this study was to evaluate the polyamine profile during gestation and its associations with maternal allergy and cytokine production in cord blood cells in response to different allergenic stimuli. METHODS: Polyamines were determined in plasma of pregnant women (24 weeks, N = 674) and in umbilical cord samples (N = 353 vein and N = 160 artery) from the Mediterranean NELA birth cohort. Immune cell populations were quantified, and the production of cytokines in response to different allergic and mitogenic stimuli was assessed in cord blood. RESULTS: Spermidine and spermine were the most prevalent polyamines in maternal, cord venous, and cord arterial plasma. Maternal allergies, especially allergic conjunctivitis, were associated with lower spermine in umbilical cord vein. Higher levels of polyamines were associated with higher lymphocyte number but lower Th2-related cells in cord venous blood. Those subjects with higher levels of circulating polyamines in cord showed lower production of inflammatory cytokines, especially IFN-α, and lower production of Th2-related cytokines, mainly IL-4 and IL-5. The effects of polyamines on Th1-related cytokines production were uncertain. CONCLUSIONS: Spermidine and spermine are the predominant polyamines in plasma of pregnant women at mid-pregnancy and also in umbilical cord. Maternal allergic diseases like allergic conjunctivitis are related to lower levels of polyamines in cord vein, which could influence the immune response of the newborn. Cord polyamine content is related to a decreased Th2 response and inflammatory cytokines production, which might be important to reduce an allergenic phenotype in the neonate.

Pravastatin reduces plasma levels of extracellular vesicles in pregnancies at high risk of term preeclampsia.

Introduction: Elevated plasma levels of extracellular vesicles have been associated with impaired placentation, angiogenesis imbalance, intravascular inflammation, and endothelial dysfunction in women with preeclampsia, thus suggesting that circulating vesicles may be a good therapeutic target for the treatment of the disease. Recently, statins have been considered a potential treatment for the prevention of preeclampsia because of their pleiotropic effects, including the improvement of endothelial dysfunction and inhibition of inflammatory responses. However, the effects of these drugs on circulating vesicles concentration in women at risk of preeclampsia have not been established. Herein, we aimed to assess the effects of pravastatin on circulating extracellular vesicle generation in women at high risk of term preeclampsia. Methods: In a sample of 68 singleton pregnant women participating in the multicenter, double-blind, placebo-controlled STATIN trial (Nº EducraCT 2016-005206-19 ISRCTN), 35 women received a placebo and 33 women received a 20 mg/day dose of pravastatin for approximately 3 weeks (from 35 to 37 weeks of gestation until delivery). Large extracellular vesicles were characterized and quantified by flow cytometry using annexin V and cell-specific antibodies directed against platelet, endothelial, leukocyte, and syncytiotrophoblast cell surface markers. Results: In women who received the placebo, a significant increase in the plasma levels of large extracellular vesicles from platelets (34%, p < 0.01), leukocytes (33%, p < 0.01), monocytes (60%, p < 0.01), endothelial cells (40%, p < 0.05), and syncytiotrophoblast cells (22%, p < 0.05) were observed. However, treatment with pravastatin significantly reduced the plasma levels of large extracellular vesicles from platelets (42%, p < 0.001), leukocytes (25%, p < 0.001), monocytes (61%, p < 0.001), endothelial cells (69%, p < 0.001), activated endothelial cells (55%, p < 0.001), and syncytiotrophoblast cells (44%, p < 0.001). Discussion: These results indicate that pravastatin reduces the levels of activated cell-derived membrane vesicles from the maternal vasculature, blood, and placental syncytiotrophoblast of women at high risk of term preeclampsia, suggesting that this statin may be beneficial in reducing endothelial dysfunction and pro-inflammatory and pro-coagulatory state characteristics of the disease.

P2X7 receptor activation impairs antitumour activity of natural killer cells.

BACKGROUND AND PURPOSE: A high number of intratumoural infiltrating natural killer (NK) cells is associated with better survival in several types of cancer, constituting an important first line of defence against tumours. Hypoxia in the core of solid tumours induces cellular stress and ATP release into the extracellular space where it triggers purinergic receptor activation on tumour-associated immune cells. The aim of this study was to assess whether activation of the purinergic receptor P2X7 by extracellular ATP plays a role in the NK cells antitumour activity. EXPERIMENTAL APPROACH: We carried out in vitro experiments using purified human NK cells triggered through P2X7 by extracellular ATP. NK cell killing activity against the tumour target cells K562 was studied by means of NK cytotoxicity assays. Likewise, we designed a subcutaneous solid tumour in vivo mouse model. KEY RESULTS: In this study we found that human NK cells, expressing a functional plasma membrane P2X7, acquired an anergic state after ATP treatment, which impaired their antitumour activity and decreased IFN-γ secretion. This effect was reversed by specific P2X7 antagonists and pretreatment with either IL-2 or IL-15. Furthermore, genetic P2rx7 knockdown resulted in improved control of tumour size by NK cells. In addition, IL-2 therapy restored the ability of NK cells to diminish the size of tumours. CONCLUSIONS AND IMPLICATIONS: Our results show that P2X7 activation represents a new mechanism whereby NK cells may lose antitumour effectiveness, opening the possibility of generating modified NK cells lacking P2X7 but with improved antitumour capacity.

Cytokine production by newborns: influence of sex and season of birth.

BACKGROUND: Immune signatures at birth could be associated with clinical outcomes and will improve our understanding of immunity prenatal programming. METHODS: Data come from 235 newborns from the cohort study NELA. Production of cytokines was determined using Luminex technology. Associations between cytokine concentrations with sex and season of birth were examined by multivariate regression models. RESULTS: Umbilical cord blood cells produced high levels of inflammatory cytokines, moderate levels of Th1/Th2/Tr-related cytokines, and low levels of Th17 cytokines. Compared to females, male newborn cells secreted higher levels of Th2 (peptidoglycan-stimulated IL-13, odds ratio [OR] = 2.26; 95% CI 1.18, 4.31, p value = 0.013) and Th17 (polyinosinic:polycytidylic acid-stimulated IL-23, OR = 1.82, 95% CI 1.01, 3.27, p value = 0.046) and lower levels of Th1 (olive-stimulated IL-2, OR = 0.56, 95% CI 0.31, 0.99, p value = 0.047) cytokines. Also, children born during warm seasons showed decreased innate cytokine response to peptidoglycan (IL-6, OR = 0.28, 95% CI 0.15, 0.52, p value < 0.001) compared to those born in cold seasons; meanwhile, adaptive immunity cytokines were more frequently secreted by children born during warm seasons in response to allergen extracts (IL-10, OR = 2.11, 95% CI 1.12, 3.96, p value = 0.020; IL-17F, OR = 3.31, 95% CI 1.83, 5.99, p value < 0.001). CONCLUSION: Newborns showed specific cytokines signatures influenced by sex and season of birth. IMPACT: There is a limited number of population-based studies on the immune status at birth and the influence of prenatal and perinatal factors on it. Characterization of cytokine signatures at birth related to the prenatal environment could improve our understanding of immunity prenatal programming. Newborns exhibit specific unstimulated and stimulated cytokine signatures influenced by sex and season of birth. Unstimulated and stimulated cytokine signatures in newborns may be associated with the development of related clinical outcomes later in life.

Cytokine profiles in cord blood in relation to prenatal traffic-related air pollution: The NELA cohort.

BACKGROUND: Outdoor air pollution may disturb immune system development. We investigated whether gestational exposure to traffic-related air pollutants (TRAP) is associated with unstimulated cytokine profiles in newborns. METHODS: Data come from 235 newborns of the NELA cohort. Innate response-related cytokines (IL-6, IFN-α, IL1-ß, and TNF-α), Th1-related (IFN-γ and IL-2), Th2-related (IL-4, IL-5, and IL-13), Th17-related (IL-17 and IL-23), and immunomodulatory cytokine IL-10 were quantified in the supernatant of unstimulated whole umbilical cord blood cells after 7 days of culture using the Luminex technology. Dispersion/chemical transport modeling was used to estimate long-term (whole pregnancy and trimesters) and short-term (15 days before delivery) residential exposures to traffic-related nitrogen dioxide (NO2 ), particulate matter (PM2.5 and PM10 ), and ozone (O3 ). We fitted multivariable logistic regression, Bayesian kernel machine regression (BKMR), and weighted quantile sum (WQS) regression models. RESULTS: NO2 during the whole pregnancy increased the odds of detection of IL-1ß (OR per 10 µg/m3 increase = 1.37; 95% CI, 1.02, 1.85) and IL-6 (OR per 10 µg/m3 increase = 1.32; 95% CI 1.00, 1.75). Increased odds of detected concentrations of IL-10 was found in newborns exposed during whole pregnancy to higher levels of NO2 (OR per 10 µg/m3 increase = 1.30; 95% CI 0.99, 1.69), PM10 (OR per 10 µg/m3 increase = 1.49; 95% CI 0.95, 2.33), and PM2.5 (OR per 5 µg/m3 increase = 1.56; 95% CI 0.97, 2.51). Exposure to O3 during the whole pregnancy increased the odds of detected IL-13 (OR per 10 µg/m3 increase = 1.22; 95% CI 1.01, 1.49). WQS model revealed first and third trimesters of gestation as windows of higher susceptibility. CONCLUSIONS: Gestational exposure to TRAP may increase detection of pro-inflammatory, Th2-related, and T regulatory cytokines in newborns. These changes might influence immune system responses later in life.

Dissecting the transcriptional program of phosphomannomutase 2-deficient cells: Lymphoblastoide B cell lines as a valuable model for congenital disorders of glycosylation studies.

Congenital disorders of glycosylation (CDG) include 150 genetically and clinically heterogeneous diseases, showing significant glycoprotein hypoglycosylation that leads to pathological consequences in multiple organs and systems whose underlying mechanisms are not yet understood. A few cellular and animal models have been used to study specific CDG characteristics, although they have given limited information due to the few CDG mutations tested and the still missing comprehensive molecular and cellular basic research. Here, we provide specific gene expression profiles, based on ribonucleic acid (RNA) microarray analysis, together with some biochemical and cellular characteristics of a total of nine control Epstein-Barr virus-transformed lymphoblastoid B cell lines (B-LCL) and 13 CDG B-LCL from patients carrying severe mutations in the phosphomannomutase 2 (PMM2) gene, strong serum protein hypoglycosylation and neurological symptoms. Significantly dysregulated genes in PMM2-CDG cells included those regulating stress responses, transcription factors, glycosylation, motility, cell junction and, importantly, those related to development and neuronal differentiation and synapse, such as carbonic anhydrase 2 (CA2) and ADAM23. PMM2-CDG-associated biological consequences involved the unfolded protein response, RNA metabolism and the endoplasmic reticulum, Golgi apparatus and mitochondria components. Changes in the transcriptional and CA2 protein levels are consistent with the CDG physiopathology. These results demonstrate the global transcriptional impact in phosphomannomutase 2-deficient cells, reveal CA2 as a potential cellular biomarker and confirm B-LCL as an advantageous model for CDG studies.

The Nutrition in Early Life and Asthma (NELA) birth cohort study: Rationale, design, and methods.

BACKGROUND: Primary prevention strategies for asthma are lacking. Its inception probably starts in utero and/or during the early postnatal period as the developmental origins of health and disease (DOHaD) paradigm suggests. OBJECTIVES: The main objective of Nutrition in Early Life and Asthma (NELA) cohort study is to unravel whether the following factors contribute causally to the developmental origins of asthma: (1) maternal obesity/adiposity and foetal growth; (2) maternal and child nutrition; (3) outdoor air pollution; (4) endocrine disruptors; and (5) maternal psychological stress. Maternal and offspring biological samples are used to assess changes in offspring microbiome, immune system, epigenome and volatilome as potential mechanisms influencing disease susceptibility. POPULATION: Randomly selected pregnant women from three health areas of Murcia, a south-eastern Mediterranean region of Spain, who fulfilled the inclusion criteria were invited to participate at the time of the follow-up visit for routine foetal anatomy scan at 19-22 weeks of gestation, at the Maternal-Fetal Medicine Unit of the "Virgen de la Arrixaca" University Clinical Hospital over a 36-month period, from March 2015 to April 2018. DESIGN: Prospective, population-based, maternal-child, birth cohort study. METHODS: Questionnaires on exposures and outcome variables were administered to mothers at 20-24 gestation week; 32-36 gestation week; and delivery. Children were surveyed at birth, 3 and 18 months of age and currently at 5 years. Furthermore, physical examinations were performed; and different measurements and biological samples were obtained at these time points. PRELIMINARY RESULTS: Among the 1350 women invited to participate, 738 (54%) were finally enrolled in the study and 720 of their children were eligible at birth. The adherence was high with 612 children (83%) attending the 3 months' visit and 532 children (72%) attending the 18 months' visit. CONCLUSION: The NELA cohort will add original and unique knowledge to the developmental origins of asthma.

MITF induces escape from innate immunity in melanoma.

BACKGROUND: The application of immune-based therapies has revolutionized cancer treatment. Yet how the immune system responds to phenotypically heterogeneous populations within tumors is poorly understood. In melanoma, one of the major determinants of phenotypic identity is the lineage survival oncogene MITF that integrates diverse microenvironmental cues to coordinate melanoma survival, senescence bypass, differentiation, proliferation, invasion, metabolism and DNA damage repair. Whether MITF also controls the immune response is unknown. METHODS: By using several mouse melanoma models, we examine the potential role of MITF to modulate the anti-melanoma immune response. ChIP-seq data analysis, ChIP-qPCR, CRISPR-Cas9 genome editing, and luciferase reporter assays were utilized to identify ADAM10 as a direct MITF target gene. Western blotting, confocal microscopy, flow cytometry, and natural killer (NK) cytotoxicity assays were used to determine the underlying mechanisms by which MITF-driven phenotypic plasticity modulates melanoma NK cell-mediated killing. RESULTS: Here we show that MITF regulates expression of ADAM10, a key sheddase that cleaves the MICA/B family of ligands for NK cells. By controlling melanoma recognition by NK-cells MITF thereby controls the melanoma response to the innate immune system. Consequently, while melanoma MITFLow cells can be effectively suppressed by NK-mediated killing, MITF-expressing cells escape NK cell surveillance. CONCLUSION: Our results reveal how modulation of MITF activity can impact the anti-melanoma immune response with implications for the application of anti-melanoma immunotherapies.

Prenatal and Perinatal Environmental Influences Shaping the Neonatal Immune System: A Focus on Asthma and Allergy Origins.

It is suggested that programming of the immune system starts before birth and is shaped by environmental influences acting during critical windows of susceptibility for human development. Prenatal and perinatal exposure to physiological, biological, physical, or chemical factors can trigger permanent, irreversible changes to the developing immune system, which may be reflected in cord blood of neonates. The aim of this narrative review is to summarize the evidence on the role of the prenatal and perinatal environment, including season of birth, mode of delivery, exposure to common allergens, a farming environment, pet ownership, and exposure to tobacco smoking and pollutants, in shaping the immune cell populations and cytokines at birth in humans. We also discuss how reported disruptions in the immune system at birth might contribute to the development of asthma and related allergic manifestations later in life.

Air pollution from traffic during pregnancy impairs newborn's cord blood immune cells: The NELA cohort.

BACKGROUND: Hazards of traffic-related air pollution (TRAP) on the developing immune system are poorly understood. We sought to investigate the effects of prenatal exposure to TRAP on cord blood immune cell distributions; and to identify gestational windows of susceptibility. METHODS: In-depth immunophenotyping of cord blood leukocyte and lymphocyte subsets was performed by flow cytometry in 190 newborns embedded in the Nutrition in Early Life and Asthma (NELA) birth cohort (2015-2018). Long-term (whole pregnancy and trimesters) and short-term (15-days before delivery) residential exposures to traffic-related nitrogen dioxide (NO2), particulate matter (PM2.5 and PM10), and ozone (O3) were estimated using dispersion/chemical transport modelling. Associations between TRAP concentrations and cord blood immune cell counts were assessed using multivariate Poisson regression models. RESULTS: Mean number of natural killer (NK) cells decreased 15% in relation to higher NO2 concentrations (≥36.4 µg/m3) during whole pregnancy (incidence relative risk (IRR), 0.85; 95% CI, 0.72, 0.99), with stronger associations in the first trimester. Higher PM2.5 concentrations (≥13.3 µg/m3) during whole pregnancy associated with a reduced mean number of cytotoxic T cells (IRR, 0.88; 95% CI, 0.78, 0.99). Newborns exposed to higher PM10 (≥23.6 µg/m3) and PM2.5 concentrations during the first and third trimester showed greater mean number of helper T type 1 (Th1) cells (P < 0.05). Decreased number of regulatory T (Treg) cells was associated with greater short-term NO2 (IRR, 0.90; 95% CI, 0.80, 1.01) and PM10 (IRR, 0.88; 95% CI, 0.77, 0.99) concentrations. CONCLUSIONS: Prenatal exposure to TRAP, particularly in early and late gestation, impairs fetal immune system development through disturbances in cord blood leukocyte and lymphocyte distributions.

CD33 (Siglec-3) Inhibitory Function: Role in the NKG2D/DAP10 Activating Pathway.

CD33 (siglec-3), a well-known target in leukemia therapy, is an inhibitory sialoadhesin expressed in human leukocytes of the myeloid lineage and some lymphoid subsets, including NK cells. It may constitute a control mechanism of the innate immune system; nevertheless, its role as an inhibitory receptor remains elusive. Using human NK cells as a cellular model, we analyzed CD33 inhibitory function upon different activating receptors. In high-cytotoxicity NKL cells, CD33 displayed a prominent inhibition on cytotoxicity triggered by the activating receptors NKG2D and, in a lower extent, 2B4, whereas it did not inhibit NKp46-induced cytotoxicity. NKp46 was partially inhibited by CD33 only when low-cytotoxicity NKL cells were tested. CD33 triggering did not inhibit IFN-γ secretion, contrasting with ILT-2 and CD94/NKG2A inhibitory receptors that inhibited cytotoxicity and IFN-γ secretion induced by all activating receptors tested. CD33-mediated inhibition of NKG2D-induced triggering involved Vav1 dephosphorylation. Our results support the role of CD33 as an inhibitory receptor preferentially regulating the NKG2D/DAP10 cytotoxic signaling pathway, which could be involved in self-tolerance and tumor and infected cell recognition.

International clinical guidelines for the management of phosphomannomutase 2-congenital disorders of glycosylation: Diagnosis, treatment and follow up.

Phosphomannomutase 2 (PMM2-CDG) is the most common congenital disorder of N-glycosylation and is caused by a deficient PMM2 activity. The clinical presentation and the onset of PMM2-CDG vary among affected individuals ranging from a severe antenatal presentation with multisystem involvement to mild adulthood presentation limited to minor neurological involvement. Management of affected patients requires a multidisciplinary approach. In this article, a systematic review of the literature on PMM2-CDG was conducted by a group of international experts in different aspects of CDG. Our managment guidelines were initiated based on the available evidence-based data and experts' opinions. This guideline mainly addresses the clinical evaluation of each system/organ involved in PMM2-CDG, and the recommended management approach. It is the first systematic review of current practices in PMM2-CDG and the first guidelines aiming at establishing a practical approach to the recognition, diagnosis and management of PMM2-CDG patients.

Correction: Natural Killer Cell Receptors and Cytotoxic Activity in Phosphomannomutase 2 Deficiency (PMM2-CDG).

[This corrects the article DOI: 10.1371/journal.pone.0158863.].

Natural Killer Cell Receptors and Cytotoxic Activity in Phosphomannomutase 2 Deficiency (PMM2-CDG).

BACKGROUND: PMM2-CDG is the most common N-glycosylation defect and shows an increased risk of recurrent and/or severe, sometimes fatal, infections in early life. We hypothesized that natural killer (NK) cells, as important mediators of the immune response against microbial pathogens and regulators of adaptive immunity, might be affected in this genetic disorder. OBJECTIVE: To evaluate possible defects on PMM2-CDG NK peripheral blood cell number, killing activity and expression of membrane receptors. METHODS: We studied fresh and activated NK cells from twelve PMM2-CDG cells. The number and expression of lymphoid surface receptors were studied by flow cytometry. The NK responsiveness (frequency of degranulated NK cells) and killing activity against K562 target cells was determined in the NK cytotoxicity assay. RESULTS: We found an increase of blood NK cells in three patients with a severe phenotype. Two of them, who had suffered from moderate/severe viral infections during their first year of life, also had reduced T lymphocyte numbers. Patient activated NK cells showed increased expression of CD54 adhesion molecule and NKG2D and NKp46 activating receptors. NKp46 and 2B4 expression was inversely correlated with the expression of NKG2D in activated PMM2-CDG cells. Maximal NK activity against K562 target cells was similar in control and PMM2-CDG cells. Interestingly, the NK cell responsiveness was higher in patient cells. NKG2D and specially CD54 increased surface expression significantly correlated with the increased NK cell cytolytic activity according to the modulation of the killer activity by expression of triggering receptors and adhesion molecules. CONCLUSIONS: Our results indicate that hypoglycosylation in PMM2-CDG altered NK cell reactivity against target cells and the expression of CD54 and NKG2D, NKp46 and 2B4 activating receptors during NK cell activation. This suggests a defective control of NK cell killing activity and the overall anti-viral immune response in PMM2-CDG patients. The present work improves our understanding of the immunological functions in PMM2-CDG and possibly in other CDG-I types.

A novel CD14(high) CD16(high) subset of peritoneal macrophages from cirrhotic patients is associated to an increased response to LPS.

The aim of this study was to characterize monocyte-derived macrophages (M-DM) from blood and ascites of cirrhotic patients comparatively with those obtained from blood of healthy controls. The phenotypic profile based on CD14/CD16 expression was analyzed by flow cytometry. Cells were isolated and stimulated in vitro with LPS and heat killed Candida albicans. Phosphorylation of ERK, c-Jun, p38 MAPK, and PKB/Akt was analyzed by Western blotting. A novel CD14(high)CD16(high) M-DM subpopulation is present in ascites (∼33%). The CD14(++)CD16(+) intermediate subset is increased in the blood of cirrhotic patients (∼from 4% to 11%) and is predominant in ascites (49%), while the classical CD14(++)CD16(-) subpopulation is notably reduced in ascites (18%). Basal hyperactivation of ERK and JNK/c-Jun pathways observed in ascites M-DM correlates with CD14/CD16 high expressing subsets, while PI3K/PKB does it with the CD16 low expressing cells. In vitro LPS treatment highly increases ERK1/2, PKB/Akt and c-Jun phosphorylation, while that of p38 MAPK is decreased in M-DM from ascites compared to control blood M-DM. Stimulation of healthy blood M-DM with LPS and C. albicans induced higher phosphorylation levels of p38 than those from ascites. Regarding cytokines secretion, in vitro activated M-DM from ascites of cirrhotic patients produced significantly higher amounts of IL-6, IL-10 and TNF-α, and lower levels of IL-1ß and IL-12 than control blood M-DM. In conclusion, a new subpopulation of CD14(high)CD16(high) peritoneal M-DM has been identified in ascites of cirrhotic patients, which is very sensitive to LPS stimulation.

MHC-I molecules selectively inhibit cell-mediated cytotoxicity triggered by ITAM-coupled activating receptors and 2B4.

NK cell effector functions are controlled by a combination of inhibitory receptors, which modulate NK cell activation initiated by stimulatory receptors. Most of the canonical NK cell inhibitory receptors recognize allelic forms of classical and non-classical MHC class I molecules. Furthermore, high expression of MHC-I molecules on effector immune cells is also associated with reverse signaling, giving rise to several immune-regulatory functions. Consequently, the inhibitory function of MHC class I expressed on a human NKL cell line and activated primary NK and T cells on different activating receptors are analyzed in this paper. Our results reveal that MHC-I molecules display specific patterns of "selective" inhibition over cytotoxicity and cytokine production induced by ITAM-dependent receptors and 2B4, but not on NKG2D. This contrasts with the best known "canonical" inhibitory receptors, which constitutively inhibit both functions, regardless of the activating receptor involved. Our results support the existence of a new fine-tuner inhibitory function for MHC-I molecules expressed on cytotoxic effector cells that could be involved in establishing self-tolerance in mature activated NK cells, and could also be important in tumor and infected cell recognition.

GPI-anchor and GPI-anchored protein expression in PMM2-CDG patients.

BACKGROUND: Mutations in PMM2 impair phosphomannomutase-2 activity and cause the most frequent congenital disorder of glycosylation, PMM2-CDG. Mannose-1-phosphate, that is deficient in this disorder, is also implicated in the biosynthesis of glycosylphosphatidyl inositol (GPI) anchors. OBJECTIVE: To evaluate whether GPI-anchor and GPI-anchored proteins are defective in PMM2-CDG patients. METHODS: The expression of GPI-anchor and seven GPI-anchored proteins was evaluated by flow cytometry in different cell types from twelve PMM2-CDG patients. Additionally, neutrophil CD16 and plasma hepatic proteins were studied by Western blot. Transferrin glycoforms were evaluated by HPLC. RESULTS: Patients and controls had similar surface expression of GPI-anchor and most GPI-anchored proteins. Nevertheless, patients displayed a significantly diminished binding of two anti-CD16 antibodies (3G8 and KD1) to neutrophils and also of anti-CD14 (61D3) to monocytes. Interestingly, CD16 immunostaining and asialotransferrin levels significantly correlated with patients' age. Analysis by flow cytometry of CD14 with MΦP9, and CD16 expression in neutrophils by Western blot using H-80 ruled out deficiencies of these antigens. CONCLUSIONS: PMM2 mutations do not impair GPI-anchor or GPI-anchored protein expression. However, the glycosylation anomalies caused by PMM2 mutations might affect the immunoreactivity of monoclonal antibodies and lead to incorrect conclusions about the expression of different proteins, including GPI-anchored proteins. Neutrophils and monocytes are sensitive to PMM2 mutations, leading to abnormal glycosylation in immune receptors, which might potentially affect their affinity to their ligands, and contribute to infection. This study also confirms less severe hypoglycosylation defects in older PMM2-CDG patients.

Role of MAP kinases and PI3K-Akt on the cytokine inflammatory profile of peritoneal macrophages from the ascites of cirrhotic patients.

AIMS: Several new approaches targeting inflammation associated with different diseases are in clinical development. OBJECTIVE: To explore the role played by MAPK and PI3K-Akt pathways on the release of cytokines in monocyte-derived macrophages (M-DM) obtained from the ascites of cirrhotic patients to identify novel targets for pharmaceutical intervention to prevent hepatic damage. METHODS: M-DM were isolated from the ascites of cirrhotic patients and stimulated in vitro with LPS and heat-killed Candida albicans in the presence or absence of the inhibitors for MEK1, p38 MAPK, JNK and PI3K. The MAPK phosphorylation levels were determined by Western Blot. Cell culture supernatants were assayed by ELISA for TNF-α, IL-6 and IL-10. RESULTS: The release of the pro-inflammatory cytokines IL-6 and TNF-α at baseline was more effectively reduced by the MAPK inhibitors, while the basal IL-10 anti-inflammatory cytokine secretion was only and strongly (90.3%) affected by the PI3K inhibitor. The incubation of peritoneal M-DM in the presence of LPS and C. albicans increased the release of IL-6, TNF-α and IL-10. LPS-induced pro-inflammatory cytokines secretion was more sensitive to MAPK inhibitors, whereas that induced by C. albicans was more susceptible to inhibition of PI3K. Finally, inhibition of PI3K almost completely suppressed the secretion of IL-10 in stimulated M-DM. CONCLUSIONS: These results demonstrate that pro-inflammatory cytokines release in M-DM from this clinical setting strongly depends on the MAPK signalling pathways, differs depending on the microbial stimulus added and confirms the prominent role of the PI3K-Akt pathway in the modulation of IL-10-mediated anti-inflammatory function.

The peritoneal macrophage inflammatory profile in cirrhosis depends on the alcoholic or hepatitis C viral etiology and is related to ERK phosphorylation.

BACKGROUND: The development of ascites in cirrhotic patients generally heralds a deterioration in their clinical status. A differential gene expression profile between alcohol- and hepatitis C virus (HCV)-related cirrhosis has been described from liver biopsies, especially those associated with innate immune responses. The aim of this work was to identify functional differences in the inflammatory profile of monocyte-derived macrophages from ascites in cirrhotic patients of different etiologies in an attempt to extrapolate studies from liver biopsies to immune cells in ascites. To this end 45 patients with cirrhosis and non-infected ascites, distributed according to disease etiology, HCV (n=15) or alcohol (n=30) were studied. Cytokines and the cell content in ascites were assessed by ELISA and flow cytometry, respectively. Cytokines and ERK phosphorylation in peritoneal monocyte-derived macrophages isolated and stimulated in vitro were also determined. RESULTS: A different pattern of leukocyte migration to the peritoneal cavity and differences in the primed status of macrophages in cirrhosis were observed depending on the viral or alcoholic etiology. Whereas no differences in peripheral blood cell subpopulations could be observed, T lymphocyte, monocyte and polymorphonuclear cell populations in ascites were more abundant in the HCV than the alcohol etiology. HCV-related cirrhosis etiology was associated with a decreased inflammatory profile in ascites compared with the alcoholic etiology. Higher levels of IL-10 and lower levels of IL-6 and IL-12 were observed in ascitic fluid from the HCV group. Isolated peritoneal monocyte-derived macrophages maintained their primed status in vitro throughout the 24 h culture period. The level of ERK1/2 phosphorylation was higher in ALC peritoneal macrophages at baseline than in HCV patients, although the addition of LPS induced a greater increase in ERK1/2 phosphorylation in HCV than in ALC patients. CONCLUSIONS: The macrophage inflammatory status is higher in ascites of alcohol-related cirrhotic patients than in HCV-related patients, which could be related with differences in bacterial translocation episodes or regulatory T cell populations. These findings should contribute to identifying potential prognostic and/or therapeutic targets for chronic liver diseases of different etiology.