The expression and clinical significance of CD59 and FLAER in Chinese adult AML patients.

BACKGROUND: The role of CD59 and fluorescently labeled aerolysin (FLAER) in acute myeloid leukemia (AML) remains unclear and requires further investigation. To explore the relationship between CD59, FLAER, and AML, we investigated CD59 and FLAER expression in AML and analyzed their relationship with clinical characteristics of AML patients. METHODS: We employed flow cytometry (FCM) to analyze CD59 and FLAER expression in 161 AML patients at Tianjin Medical University General Hospital and evaluated its association with sex, white blood cell (WBC) count, platelet (PLT) count, thrombin time (TT), prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), D-Dimer(D-D), and lactate dehydrogenase (LDH), followed by analyzing its connection with disease progression and complete remission (CR). RESULTS: CD59 and FLAER deficiencies were identified in AML patients. Compared with CR group, non-CR group patients revealed more CD59 and FLAER deficiency. Compared with non-acute promyelocytic leukemia (M3) group, M3 group patients had more CD59 and FLAER deficiency. CD59- level in primordial cells of M3 patients was positively correlated with primordial cell ratio (r = 0.660, p = 0.003). Additionally, we discovered that the decline in CD59 and FLAER levels might be linked to higher D-D and LDH in AML patients. The difference was statistically significant (p < 0.05). CONCLUSIONS: We demonstrated that the decline in CD59 and FLAER levels was associated with leukemia cell proliferation and abnormal coagulation function in AML, suggesting that they could serve as a predictor of AML coagulation dysfunction, particularly in M3.

Levels of lymphocyte-associated regulators of complement system CD55 and CD59 are changed in schizophrenia patients.

OBJECTIVE: Although pathological mechanisms of schizophrenia are unknown, evidence in the literature suggests that the immune system might be involved in the pathogenesis. Complement is an important part of the immune system and it has been suggested to play role in the pathogenesis of schizophrenia. We aimed to investigate the potential involvement of the complement system in schizophrenia by the determination of peripheral concentrations of certain complement proteins and their regulators in patients. METHODS: Plasma concentrations of complement C3, C4, and C1 inhibitory protein were measured by chemiluminescence in 41 schizophrenia patients and 39 healthy controls. Expression of CD55, CD59, and CD46 proteins on peripheral blood mononuclear cells were determined by flow cytometry in the same groups. RESULTS: Frequencies of peripheral immune cells expressing CD55 were determined to be significantly higher in schizophrenia patients than in healthy people (p = 0.020). Frequencies of peripheral immune cells expressing CD59 was determined to be significantly higher in healthy people than in schizophrenia patients (p = 0.012). The expression level of CD55 per cell was measured to be significantly elevated in patients compared to healthy controls (p = 0.026). CONCLUSIONS: Our data clearly demonstrate an elevated complement activity in schizophrenia and points to a possible complement association in the pathogenesis.Key pointsIncreased the expression level, and frequency of CD55 in schizophrenia patients.Decreased frequency of CD59 in schizophrenia patients.No difference in the expression level of CD59; the expression level, and frequency of CD46; frequency of complement C3, C4, and C1 inhibitory protein.

Serum CD59: a novel biomarker of idiopathic pulmonary fibrosis?

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is the most common among idiopathic interstitial pneumonia. Life expectancy is estimated around 3-5 years at diagnosis. No reliable prognostic biomarker has been approved for routinary clinical practice of IPF. The aim of this study is to investigate the potential prognostic value of serum CD59 in a cohort of IPF patients. METHODS: Fifty-seven patients (45 males, 66.1±10 years old) were recruited in Siena Regional Referral Center for Interstitial Lung Disease and underwent serum sampling for CD59 detection during diagnostic pathway. Clinical, functional, radiological and survival data were retrospectively collected. As control group for CD59 values, we recruited eight healthy volunteers (five males, 59.2±18 years old). RESULTS: CD59 levels were significantly higher in IPF patients in respect with healthy controls (P=0.0238). Patients with CD59 concentrations lower than 15 ng/mL reported a significant reduction of survival time (P=0.009); current or former smokers with CD59 <15 ng/mL showed the worst prognosis (P=0.014). CONCLUSIONS: CD59 levels were significantly increased in IPF patients, supporting the existence of epithelial damage in the pathogenesis of disease. Lower values of CD59 were associated with a significantly worse prognosis, suggesting a potential role of CD59 in the prognostic estimation of IPF patients.

Plasma CD59 concentrations are increased in preeclampsia with severe features and correlate with laboratory measures of end-organ injury.

OBJECTIVES: Dysregulation of CD59 may lead to increased complement-mediated end-organ injury in preeclampsia. We sought to determine if soluble CD59 concentrations are altered in preeclampsia with severe features. STUDY DESIGN: Observational case-control study, which enrolled subjects prospectively from six centers in Colombia from 2015 to 2016. Cases had preeclampsia with severe features and controls were either healthy or had chronic hypertension, gestational hypertension, or preeclampsia without severe features. Trained coordinators collected clinical data, blood and urine. Analyses were by test of medians and Spearman's correlation. MAIN OUTCOME MEASURES: Soluble CD59 concentration in plasma and urine, using enzyme linked immunosorbent assays. RESULTS: In total, 352 subjects were enrolled (104 cases; 248 controls). Compared to healthy women or those with other hypertensive disorders of pregnancy, women with preeclampsia with severe features had increased concentration of CD59 in plasma (P < 0.001) and decreased CD59 in urine (P = 0.01). In sub-group analyses, plasma CD59 concentrations were increased in preeclampsia with severe features compared to healthy controls (P < 0.001) or controls with either chronic hypertension (P = 0.002) or gestational hypertension (P = 0.02). Increased plasma CD59 concentrations correlated with decreased platelet count and increased lactate dehydrogenase, creatinine, aspartate transaminase, urine protein/creatinine ratio, systolic blood pressure and diastolic blood pressure (P < 0.01, all correlations). CONCLUSION: In women with preeclampsia with severe features, soluble CD59 concentrations were increased in plasma and decreased in urine, and plasma levels correlated with increased blood pressure and end-organ injury. Soluble CD59 concentrations may help identify a subset of women with preeclampsia that have altered regulation of terminal complement proteins.

Plasma glycated CD59 (gCD59), a novel biomarker for the diagnosis, management and follow up of women with Gestational Diabetes (GDM) - protocol for prospective cohort study.

BACKGROUND: The prevalence of Gestational Diabetes (GDM) is rising and with it the number of mothers and children at risk of adverse outcomes. As treatment has been shown to reduce adverse events, it is imperative that we identify all at-risk pregnant women. In Ireland, the national standard of care is selective screening with a 2-hour 75 g oral glucose tolerance test (OGTT). Aiming for universal screening is of utmost importance but this is difficult given the length, the unfeasibility and impracticability of the OGTT. We aim to assess if the novel biomarker glycated CD59 (gCD59) is a suitable contender for the OGTT in identifying women with GDM. METHODS: In this prospective cohort study, the study participants will be consecutive pregnant women at Galway University Hospital, Galway, Ireland. Samples for the plasma gCD59 biomarker will be taken together with routine bloods at the first antenatal visit, at weeks 24-28 at the time of routine 75 g OGTT, in trimester 3- and 12-weeks post-partum for women with GDM while having their routine post-partum 75 g OGTT. The constructed database will contain baseline information on each study participant, baseline laboratory data, follow-up laboratory data and pregnancy related outcomes. We aim to recruit a total of 2,000 participants over the project period and with a national GDM prevalence of 12-13%, we will have 240-260 subjects who meet OGTT criteria for GDM. Following regional prevalence, we expect to have 34-37 women who will develop either diabetes or pre-diabetes in the early post-partum period. The sensitivity and specificity of plasma gCD59 to predict the results of the OGTT will be assessed using nonparametric estimates of the receiver operating characteristic (ROC) curves and respective area under the ROC curve (AUROC). DISCUSSION: A body of clinical and experimental evidence supports a link between the complement system, complement regulatory proteins, and the pathogenesis of diabetes complications. Building on this research, our study plans to look at the plasma gCD59 capacity to classify pregnant women with normal or abnormal glucose tolerance but also to assess if plasma gCD59 can be used as an early predictor for GDM, for adverse pregnancy outcomes and/or post-partum glucose intolerance.

Plasma Glycated CD59 Predicts Early Gestational Diabetes and Large for Gestational Age Newborns.

CONTEXT: Gestational diabetes mellitus (GDM) diagnosed in early pregnancy is a health care challenge because it increases the risk of adverse outcomes. Plasma-glycated CD59 (pGCD59) is an emerging biomarker for diabetes and GDM. The aim of this study was to assess the performance of pGCD59 as a biomarker of early GDM and its association with delivering a large for gestational age (LGA) infant. OBJECTIVES: To assess the performance of pGCD59 to identify women with GDM in early pregnancy (GDM < 20) and assess the association of pGCD59 with LGA and potentially others adverse neonatal outcomes linked to GDM. METHODS: Blood levels of pGCD59 were measured in samples from 693 obese women (body mass index > 29) undergoing a 75-g, 2-hour oral glucose tolerance test (OGTT) at <20 weeks' gestation in the Vitamin D and Lifestyle Intervention study: the main analyses included 486 subjects who had normal glucose tolerance throughout the pregnancy, 207 who met criteria for GDM at <20 weeks, and 77 diagnosed with GDM at pregnancy weeks 24 through 28. Reference tests were 75-g, 2-hour OGTT adjudicated based on International Association of Diabetes and Pregnancy Study Group criteria. The index test was a pGCD59 ELISA. RESULTS: Mean pGCD59 levels were significantly higher (P < 0.001) in women with GDM < 20 (3.9 ±â€…1.1 standard peptide units [SPU]) than in those without (2.7 ±â€…0.7 SPU). pGCD59 accurately identified GDM in early pregnancy with an area under the curve receiver operating characteristic curves of 0.86 (95% confidence interval [CI], 0.83-0.90). One-unit increase in maternal pGCD59 level was associated with 36% increased odds of delivering an LGA infant (odds ratio for LGA vs non-LGA infant: 1.4; 95% CI, 1.1-1.8; P = 0.016). CONCLUSION: Our results indicate that pGCD59 is a simple and accurate biomarker for detection of GDM in early pregnancy and risk assessment of LGA.

Complement activation in the plasma and placentas of women with different subsets of antiphospholipid syndrome.

PROBLEM: As antiphospholipid antibody-positive women with adverse pregnancy outcomes have higher plasma complement activation product levels, and the placentas of women with antiphospholipid syndrome (APS) exhibit C4d complement component deposition, complement activation involvement has been hypothesized in APS pregnancy complications. METHOD OF STUDY: Plasma levels of C5a and C5b-9 complement components of 43 APS non-pregnant patients and 17 pregnant APS women were measured using enzyme-linked immunosorbent assay. The results were compared with those of 16 healthy non-pregnant women and eight healthy pregnant women, respectively. Placenta samples of five APS patients at high risk of pregnancy complications and of five healthy controls were subjected to immunoblotting analysis with specific antibodies to C5b-9 and CD46, CD55, CD59 complement regulators. RESULTS: The mean plasma C5a and C5b-9 levels were significantly higher in the non-pregnant APS patients with previous thrombosis ± pregnancy morbidity (P = .0001 and P = .0034, respectively) and in the pregnant APS women with adverse outcomes (P = .0093 for both). Similarly, C5b-9 amounts were significantly higher in the adverse pregnancy outcome placenta (P = .0115) than in those associated to a favorable outcome. The mean CD46, CD55 and CD59 amounts were, instead, lower, although not always significantly, in the placentas of all the high-risk APS women with respect to the control placentas. CONCLUSION: Data analysis demonstrated that there was significant complement activation in the more severe subset of APS patients and in only the adverse pregnancy outcome APS women. Further studies will clarify whether the lower CD46, CD55, and CD59 expressions in the APS placentas are limited to only high-risk APS patients.

Sensitive and accurate identification of PNH clones based on ICCS/ESCCA PNH Consensus Guidelines-A summary.

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare hematopoietic stem cell disorder resulting from the somatic mutation of the X-linked phosphatidyl-inositol glycan complementation Class A (PIG-A) gene. Depending on the severity of the mutation in the PIG-A gene, there is a partial or absolute inability to make glycosylphosphatidyl-inositol (GPI)-anchored proteins including complement-defense structures such as CD55 and CD59 on RBCs and WBCs. Flow cytometric detection of PNH clones has become the gold standard and has played an increasingly important role in the diagnosis, monitoring, and clinical management of patients with PNH. Recently, a 4-part set of Consensus Guidelines have been published by flow experts in the field to address the key assay-specific considerations for the identification of PNH clones in RBC and WBC, how to report such data and a full validation document for the assays described. Below, we have summarized the most significant aspects of this International effort.

Measurement of soluble CD59 in CSF in demyelinating disease: Evidence for an intrathecal source of soluble CD59.

BACKGROUND: CD59, a broadly expressed glycosylphosphatidylinositol-anchored protein, is the principal cell inhibitor of complement membrane attack on cells. In the demyelinating disorders, multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD), elevated complement protein levels, including soluble CD59 (sCD59), were reported in cerebrospinal fluid (CSF). OBJECTIVES: We compared sCD59 levels in CSF and matched plasma in controls and patients with MS, NMOSD and clinically isolated syndrome (CIS) and investigated the source of CSF sCD59 and whether it was microparticle associated. METHODS: sCD59 was quantified using enzyme-linked immunosorbent assay (ELISA; Hycult; HK374-02). Patient and control CSF was subjected to western blotting to characterise anti-CD59-reactive materials. CD59 was localised by immunostaining and in situ hybridisation. RESULTS: CSF sCD59 levels were double those in plasma (CSF, 30.2 ng/mL; plasma, 16.3 ng/mL). Plasma but not CSF sCD59 levels differentiated MS from NMOSD, MS from CIS and NMOSD/CIS from controls. Elimination of microparticles confirmed that CSF sCD59 was not membrane anchored. CONCLUSION: CSF levels of sCD59 are not a biomarker of demyelinating diseases. High levels of sCD59 in CSF relative to plasma suggest an intrathecal source; CD59 expression in brain parenchyma was low, but expression was strong on choroid plexus (CP) epithelium, immediately adjacent the CSF, suggesting that this is the likely source.

Complement-driven anemia: more than just paroxysmal nocturnal hemoglobinuria.

Atypical hemolytic uremic syndrome (aHUS); hemolysis, elevated liver function tests, and low platelets syndrome; and transplant-associated thrombotic microangiopathy are related conditions, in that many patients harbor germline heterozygous mutations in genes that regulate the alternative pathway of complement (APC). Penetrance is variable because development of clinically significant disease appears to require supervention of a process such as inflammation. Complement activation on the endothelial surfaces leads to endothelial damage, platelet consumption, microthrombi, and a mechanical hemolytic anemia with schistocytes. Paroxysmal nocturnal hemoglobinuria (PNH) is a clonal hematopoietic disease caused by expansion of a stem cell that harbors a somatic mutation in PIGA PIGA mutant blood cells are deficient in the complement regulator proteins CD55 and CD59, making them susceptible to intravascular hemolysis due to a failure to regulate the APC on erythrocytes. Eculizumab is a monoclonal antibody that binds to C5 and inhibits terminal complement by interfering with the cleavage of C5 by the C5 convertases. The drug is approved by the US Food and Drug Administration for the treatment of aHUS and PNH; however, a new generation of complement inhibitors that block C5 and other components of the complement cascade is showing promise in preclinical and clinical trials.

Effects of prenatal n-3 fatty acid supplementation on offspring resolvins at birth and 12 years of age: a double-blind, randomised controlled clinical trial.

Resolution of inflammation is an active process involving specialised pro-resolving mediators (SPM) generated from the n-3 fatty acids EPA and DHA. n-3 Fatty acid supplementation during pregnancy may provide an intervention strategy to modify these novel SPM. This study aimed to assess the effect of n-3 fatty acid supplementation in pregnancy on offspring SPM at birth and 12 years of age (12 years). In all, ninety-eight atopic pregnant women were randomised to 3·7 g daily n-3 fatty acids or a control (olive oil), from 20 weeks gestation until delivery. Blood was collected from the offspring at birth and at 12 years. Plasma SPM consisting of 18-hydroxyeicosapentaenoic acid (18-HEPE), E-series resolvins, 17-hydroxydocosahexaenoic acid (17-HDHA), D-series resolvins, 14-hydroxydocosahexaenoic acid (14-HDHA), 10 S,17S-dihydroxydocosahexaenoic acid, maresins and protectin 1, were measured by liquid chromatography-tandem MS. We identified the resolvins RvE1, RvE2, RvE3, RvD1, 17R-RvD1 and RvD2 for the first time in human cord blood. n-3 Fatty acids increased cord blood 18-HEPE (P<0·001) derived from EPA relative to the control group. DHA-derived 17-HDHA at birth was significantly increased in the n-3 fatty acid group relative to the controls (P=0·001), but other SPM were not different between the groups. n-3 Fatty acid supplementation during pregnancy was associated with an increase in SPM precursors in the offspring at birth but the effects were not sustained at 12 years. The presence of these SPM, particularly at birth, may have functions relevant in the newborn that remain to be established, which may be useful for future investigations.

C-reactive protein upregulates the whole blood expression of CD59 - an integrative analysis.

Elevated C-reactive protein (CRP) concentrations in the blood are associated with acute and chronic infections and inflammation. Nevertheless, the functional role of increased CRP in multiple bacterial and viral infections as well as in chronic inflammatory diseases remains unclear. Here, we studied the relationship between CRP and gene expression levels in the blood in 491 individuals from the Estonian Biobank cohort, to elucidate the role of CRP in these inflammatory mechanisms. As a result, we identified a set of 1,614 genes associated with changes in CRP levels with a high proportion of interferon-stimulated genes. Further, we performed likelihood-based causality model selection and Mendelian randomization analysis to discover causal links between CRP and the expression of CRP-associated genes. Strikingly, our computational analysis and cell culture stimulation assays revealed increased CRP levels to drive the expression of complement regulatory protein CD59, suggesting CRP to have a critical role in protecting blood cells from the adverse effects of the immune defence system. Our results show the benefit of integrative analysis approaches in hypothesis-free uncovering of causal relationships between traits.

Plasma Glycated CD59, a Novel Biomarker for Detection of Pregnancy-Induced Glucose Intolerance.

OBJECTIVE: Plasma glycated CD59 (pGCD59) is an emerging biomarker in diabetes. We assessed whether pGCD59 could predict the following: the results of the glucose challenge test (GCT) for screening of gestational diabetes mellitus (GDM) (primary analysis); and the diagnosis of GDM and prevalence of large for gestational age (LGA) newborns (secondary analyses). RESEARCH DESIGN AND METHODS: Case-control study of 1,000 plasma samples from women receiving standard prenatal care, 500 women having a normal GCT (control subjects) and 500 women with a failed GCT and a subsequent oral glucose tolerance test (case patients). RESULTS: Compared with control subjects, the median (interquartile range) pGCD59 value was 8.5-fold higher in case patients and 10-fold higher in GDM patients, as follows: control subjects 0.33 (0.19); case patients 2.79 (1.4); GDM patients 3.23 (1.43) (P < 0.001); area under the receiver operating characteristic curve 0.92. LGA prevalence was 4.3% in the lowest quartile and 13.5% in the highest quartile of pGCD59. CONCLUSIONS: One pGCD59 measurement during weeks 24-28 identifies pregnancy-induced glucose intolerance with high sensitivity and specificity and can potentially identify the risk for LGA.

Pathophysiological aspects of red blood cells in end-stage renal disease patients resistant to recombinant human erythropoietin therapy.

OBJECTIVE: Modified, bioreactive red blood cells (RBCs) and RBC-derived microvesicles (MVs) likely contribute to the hematological and cardiovascular complications in end-stage renal disease (ESRD). This study assesses the physiological profile of RBCs in patients with ESRD receiving standard or high doses of recombinant human erythropoietin (rhEPO). METHOD: Blood samples from twenty-eight patients under sustained hemodialysis, responsive, or not to standard rhEPO administration were examined for RBC morphology, fragility, hemolysis, redox status, removal signaling, membrane protein composition, and microvesiculation before and after dialysis. Acute effects of uremic plasma on RBC features were examined in vitro through reconstitution experiments. RESULTS: Overall, the ESRD RBCs were characterized by pathological levels of shape distortions, surface removal signaling, and membrane exovesiculation, but reduced fragility compared to healthy RBCs. Irreversible transformation of RBCs was found to be a function of baseline Hb concentration. The more toxic uremic context in non-responsive patients compared to rhEPO responders was blunted in part by the antioxidant, antihemolytic, and anti-apoptotic effects of high rhEPO doses, and probably, of serum uric acid. A selective lower expression of RBC membrane in complement regulators (CD59, clusterin) and of CD47 "marker-of-self" was detected in non-responders and responders, respectively. Evidence for different short-term dialysis effects and probably for a different erythrocyte vesiculation mechanism in rhEPO responsive compared to non-responsive patients was also revealed. CONCLUSION: Deregulation of RBC homeostasis might involve diverse molecular pathways driving erythrocyte signaling and removal in rhEPO non-responders compared to responsive patients.

Expression pattern of CD55 and CD59 on red blood cells in sickle cell disease.

OBJECTIVES: To investigate the pattern of CD55 and CD59 expression on RBCs of SCD patients, and its association with anemia, biochemical parameters of hemolysis, level of erythropoietin, and pro-inflammatory markers. METHODS: Flow cytometric analysis was performed on RBCs from 71 adult SCD patients and 53 healthy controls, using the commercial REDQUANT kit. RESULTS: CD59 deficiency was significantly higher among SCD patients than among healthy controls. The proportions of CD55-deficient and CD59-deficient RBCs from SCD patients were significantly higher when compared with those from healthy controls (0.17 vs. 0.09 and 2.1 vs. 1.2, respectively). The MFI of CD55 and CD59 expression on RBCs in SCD was significantly reduced when compared to the expression in healthy controls (5.2 vs. 6.4 and 19.4 vs 20.3, respectively). The pattern of CD55 and CD59 expression was not correlated with anemia, biomarkers of hemolysis, erythropoietin level, or other pro-inflammatory markers. DISCUSSION: There is an altered pattern of CD55 and CD59 expression on RBCs of SCD Patients; however, it does not seem to play a causal role in the pathophysiology of anemia, and is unlikely to be influenced by the level of erythropoietin or other inflammatory mediators.

Value of CD16/CD66b/CD45 in comparison to CD55/CD59/CD45 in diagnosis of paroxysmal nocturnal haemoglobinuria: An Indian experience.

BACKGROUND & OBJECTIVES: Diagnosis of paroxysmal nocturnal haemoglobinuria (PNH), a rare haematopoietic stem cell disorder, is challenging in patients with bone marrow failure (BMF) syndrome like aplastic anaemia (AA). This study was conducted with the aim to test the efficacy of the newly recommended markers viz. anti-CD16 and CD66b antibody over the existing anti-CD55 and CD59 antibody for PNH diagnosis in India. METHODS: This study was conducted on 193 suspected cases of PNH by flow cytometry using lyse wash technique to stain the granulocytes with CD16/CD66b and CD55/CD59. RESULTS: Of the 193 suspected cases, 62 patients showed the presence of PNH clone. Forty six patients were detected by CD55/CD59/CD45, whereas 61 were detected by CD16/CD66b/CD45. CD16/CD66b detected 16 (25.8%) additional patients over CD55/CD59 (P<0.05) and was more sensitive in detecting the PNH clone with higher negative predictive value. Most of the patients (11/16) who were picked up by CD16/CD66b were of AA who had small clone sizes. Further, the PNH clones were more discreetly identified in CD16/CD66b plots than by CD55/CD59. Clone size assessed by CD16/CD66b which reflects the clinical severity of classical PNH (thrombosis/haemolysis), was more representative of the underlying clinical condition than CD55/59. INTERPRETATION & CONCLUSIONS: In our experience of 62 patients of PNH, CD16/CD66b proved to be more efficacious in detecting PNH. The new panel was especially useful in monitoring PNH associated with BMF which had small clone sizes.

Etiopathological mechanisms and clinical characteristics of hyperhemolysis syndrome in Spanish patients with thalassemia.

Hyperhemolysis syndrome (HHS) is characterized by severe intravascular hemolysis with a decrease in the reticulocyte count, which is triggered and aggravated by transfusion and cannot be explained by standard immunohematological studies. A nationwide study was conducted in order to retrospectively identify thalassemia patients with HHS in Spain in order to assess pre-disposing mechanisms for this syndrome. For this, the expression of adhesion (CD49, CD36) and complement-related molecules (C3a, CD59) and the levels of reticulocyte apoptosis and macrophage activation were measured in 4 thalassemia patients with HHS, 14 patients without HHS, and 10 healthy subjects. Five of the six thalassemia patients had δß-thalassemia. The patients were not alloimmunized prior to the syndrome, which was developed after the first transfusion in all but one case. Patients with δß-thalassemia did not respond to corticoids or immunoglobulins; only splenectomy was successful. The expression of CD49 (α4ß1 integrin) was far higher in patients who had experienced HHS (85.07 ± 18.46 vs. 46.28 ± 24.31; p < 0.01), and the difference remained significant after correcting by the number of molecules analyzed (Bonferroni p < 0.05). In our population, δß-thalassemia was the most common hemoglobinopathy in patients with HHS. Furthermore, the risk to develop this syndrome may be associated with an increased expression of α4ß1 integrin.

Soluble CD59 is a Novel Biomarker for the Prediction of Obstructive Chronic Lung Allograft Dysfunction After Lung Transplantation.

CD59 is a complement regulatory protein that inhibits membrane attack complex formation. A soluble form of CD59 (sCD59) is present in various body fluids and is associated with cellular damage after acute myocardial infarction. Lung transplantation (LTx) is the final treatment for end-stage lung diseases, however overall survival is hampered by chronic lung allograft dysfunction development, which presents itself obstructively as the bronchiolitis obliterans syndrome (BOS). We hypothesized that, due to cellular damage and activation during chronic inflammation, sCD59 serum levels can be used as biomarker preceding BOS development. We analyzed sCD59 serum concentrations in 90 LTx patients, of whom 20 developed BOS. We observed that BOS patients exhibited higher sCD59 serum concentrations at the time of diagnosis compared to clinically matched non-BOS patients (p = 0.018). Furthermore, sCD59 titers were elevated at 6 months post-LTx (p = 0.0020), when patients had no BOS-related symptoms. Survival-analysis showed that LTx patients with sCD59 titers ≥400 pg/ml 6 months post-LTx have a significant (p < 0.0001) lower chance of BOS-free survival than patients with titers ≤400 pg/ml, 32% vs. 80% respectively, which was confirmed by multivariate analysis (hazard ratio 6.2, p < 0.0001). We propose that circulating sCD59 levels constitute a novel biomarker to identify patients at risk for BOS following LTx.

Are there any additional mechanisms for haemolysis in HELLP syndrome?

HELLP syndrome is a microangiopathy that leads to severe maternal complications. The objective of this study was to identify any additional mechanisms that could have contributed to HELLP syndrome-induced haemolysis. This is a pilot, prospective and observational study that lasted 9months. All patients with HELLP syndrome treated at academic tertiary care women hospital accepted to participate. Sixteen patients were included. In ten patients (63%), schizocytes were detected following a blood smear test. Six patients (38%) were diagnosed with a partial expression deficiency of proteins regulating the complement system (CD 55 or CD 59). In nine patients (56%), an activation of the complement classical pathway was detected. In two patients (13%), an ADAMTS 13 activity below 30% was detected. Three patients (19%) were diagnosed with a folate deficiency and one (6%) with an antiphospholipid syndrome. All patients developed maternal or fetal morbidity including nine (56%) an acute kidney injury. All patients but one had at least one additional mechanism that could contribute to haemolysis, besides a simple physical injury. Larger studies should be promoted to understand haemolysis in HELLP syndrome.