Association of Ficolin-3 with Severity and Outcome of Chronic Heart Failure

BACKGROUND: Inflammatory mechanisms involving complement activation has been shown to take part in the pathophysiology of congestive heart failure, but the initiating mechanisms are unknown. We hypothesized that the main initiator molecules of the lectin complement pathway mannose-binding lectin (MBL), ficolin-2 and ficolin-3 were related to disease severity and outcome in chronic heart failure. METHODS AND RESULTS: MBL, ficolin-2 and ficolin-3 plasma concentrations were determined in two consecutive cohorts comprising 190 patients from Hungary and 183 patients from Norway as well as controls. Disease severity and clinical parameters were determined at baseline, and all-cause mortality was registered after 5-years follow-up. In univariate analysis a low level of ficolin-3, but not that of MBL or ficolin-2, was significantly associated with advanced heart failure (New York Heart Association Class IV, p<0.001 for both cohorts) and showed inverse correlation with B- type natriuretic peptide (BNP) levels (r = -0.609, p<0.001 and r = -0.467, p<0.001, respectively). In multivariable Cox regression analysis, adjusted for age, gender and BNP, decreased plasma ficolin-3 was a significant predictor of mortality (HR 1.368, 95% CI 1.052-6.210; and HR 1.426, 95% CI 1.013-2.008, respectively). Low ficolin-3 levels were associated with increased complement activation product C3a and correspondingly decreased concentrations of complement factor C3. CONCLUSIONS: This study provides evidence for an association of low ficolin-3 levels with advanced heart failure. Concordant results from two cohorts show that low levels of ficolin-3 are associated with advanced heart failure and outcome. The decrease of ficolin-3 was associated with increased complement activation

Dialysebehandling av spedbarn med terminal nyresvikt

Background. End stage renal failure in infants is rare, and was until recently regarded as untreatable. Advancements in dialysis techniques and other renal replacement therapy, have now made lifesaving treatment possible. Material and methods. Three infants who developed end stage renal failure shortly after birth and were subsequently treated with long-term dialysis (as a bridge to transplantation) are presented and their results are compared with those from other dialysis centres. Results and interpretation. All three patients were successfully dialysed until transplantation, two with peritoneal dialysis and one with haemodialysis. Complications were rare and manageable. The results are in accordance with findings from previous studies. Long-term dialysis in infants with chronic renal failure should no longer be considered experimental and is now a real alternative until the child is big enough to have a transplantation. Treatment outcome is affected by co-morbidity. The treatment requires a multidisciplinary approach with specialists from many fields including paediatrics, paediatric surgery, nephrology, nutrition and dialysis. In addition it is essential to cooperate with the parents, as the treatment is demanding for the family as well as for the medical personnel

Targeting innate immune pathways in acute infectious and sterile inflammation – The role of complement

The complement system is part of the immediate innate immune response to pending danger. However, uncontrolled activation contributes to the pathophysiology of many human diseases. Complement inhibitory therapy is approved for three rare complement-mediated diseases, and this therapeutic approach is emerging for several other diseases where complement activation is implicated. The aim of this thesis was to study the effect of complement inhibition in human in vitro and porcine in vivo models of acute bacterial and sterile inflammation, and evaluate therapeutic complement inhibition in a case of severe antiphospholipid syndrome. Both complement and toll-like receptor (TLR) activation are implicated in the pathophysiology of sepsis. However, the TLR-4 antagonist eritoran failed in a sepsis trial. We found that combining inhibition of complement and TLR co-receptor CD14 attenuated Gram-negative and Gram-positive bacteria-induced inflammation more efficiently than using eritoran. This effect was demonstrated in human whole blood and endothelial cells, indicating that broad inhibition of innate immunity is necessary to effectively attenuate bacterial induced inflammation. Sterile inflammation occurs during ischemia-reperfusion injury, aggravating the initial injury. We showed in a porcine myocardial infarction model that complement inhibition reduced infarct size and improved cardiac function, highlighting the complement system as a potential treatment target in myocardial infarction. Finally, in a pregnant patient with antiphospholipid syndrome, treatment with the complement C5 blocking monoclonal antibody eculizumab did not affect the infant as merely trace amounts passed the placenta. Further, we showed that closely monitoring this therapy with adequate laboratory methods is needed to ensure efficient C5 inhibition. Overall, complement inhibition has reached the clinic and several acute inflammatory diseases might benefit from this new therapeutic approach

Human endothelial cell activation by Escherichia coli and staphylococcus aureus is mediated by TNF and IL-1β secondarily to activation of C5 and CD14 in whole blood

Endothelial cells (EC) play a central role in inflammation. E-selectin and ICAM-1 expression are essential for leukocyte recruitment and are good markers of EC activation. Most studies of EC activation are done in vitro using isolated mediators. The aim of the present study was to examine the relative importance of pattern recognition systems and downstream mediators in bacteria-induced EC activation in a physiological relevant human model, using EC incubated with whole blood. HUVEC were incubated with human whole blood. Escherichia coli– and Staphylococcus aureus–induced EC activation was measured by E-selectin and ICAM-1 expression using flow cytometry. The mAb 18D11 was used to neutralize CD14, and the lipid A analog eritoran was used to block TLR4/MD2. C5 cleavage was inhibited using eculizumab, and C5aR1 was blocked by an antagonist. Infliximab and canakinumab were used to neutralize TNF and IL-1β. The EC were minimally activated when bacteria were incubated in serum, whereas a substantial EC activation was seen when the bacteria were incubated in whole blood. E. coli–induced activation was largely CD14-dependent, whereas S. aureus mainly caused a C5aR1-mediated response. Combined CD14 and C5 inhibition reduced E-selectin and ICAM-1 expression by 96 and 98% for E. coli and by 70 and 75% for S. aureus. Finally, the EC activation by both bacteria was completely abolished by combined inhibition of TNF and IL-1β. E. coli and S. aureus activated EC in a CD14- and C5-dependent manner with subsequent leukocyte secretion of TNF and IL-1β mediating the effect

Medikamentell tromboseprofylakse : KLOK-oppgave

Bakgrunn og kunnskapsgrunnlag: Venøs tromboembolisme inkluderer dyp venetrombose og lungeemboli. Det har blitt vist at fatale lungeembolier står for 7-10 % av all sykehusrelatert død og at majoriteten av disse er innlagt på indremedisinske avdelinger. Samtidig har flere studier vist at det er et betydelig underforbruk av farmakologisk profylakse hos medisinske pasienter. Blant annet viser en norsk studie fra 2007 at medikamentell tromboseprofylakse kun ble gitt ved 20 % av innleggelsene der det var indikasjon for slik. Begrunnet tiltak, metode og organisering: Med bakgrunn i dette har vi foreslått tiltak som kan implementeres på indremedisinske avdelinger for å øke andelen pasienter som får medikamentell tromboseprofylakse i henhold til retningslinjene. Målet med tiltaket er å redusere tromboemboliske episoder og dermed redusere sykelighet og dødelighet forårsaket av dette De fleste studier vi har lest, konkluderer med at en sammensatt strategi vil være den mest effektive metode for reduksjon av tromboemboliske hendelser. I vårt forbedringstiltak foreslår vi et prosjekt som initieres med et informasjonsmøte for de ansatte på avdelingen der kunnskapsgrunnlaget for tromboseprofylakse og forbedringspotensialet ved avdelingen presenteres. Vi ønsker å involvere ledelsen, leger og sykepleiere og dermed danne grunnlag for et tverrfaglig prosjekt. Videre vil vi utforme en sjekkliste og etablere rutiner rundt bruken av denne. Sjekklisten skal inneholde indikasjoner for tromboseprofylakse. Denne skal følge pasientens kurve fra innkomst og gjennom hele oppholdet, og på den måten avklare pasientens risiko og hindre forglemmelse. Til slutt anbefaler vi at prosjektet evalueres. Indikatoren vår er andel pasienter som i følge retningslinjene skal ha tromboseprofylakse og som faktisk får det, før og etter tiltaket settes i verk Denne indikatoren bruker vi som et indirekte mål på redusert sykelighet og dødelighet som følge av tromboembolisk sykdom. Resultat/vurdering: Vi valgte et problemområdet som er godt dokumentert: Flere studier viser at medikamentell tromboseprofylakse reduserer insidensen av VTE, og videre er det veldokumentert at det er et betydelig underforbruk av dette. Forbedringstiltaket skal være enkelt og gjennomførbart. Vi hadde også fokus på enklest mulig krav til organisering. Vi valgte altså en tredelt forbedringsstrategi: 1) informasjon til avdelingen 2) tverrfaglig tilnærming inkludert definert ansvarlig lege som setter pasienten på tromboseprofylakse og 3) bruk av sjekkliste for å avklare tromboserisiko og hindre forglemmelse. Det kan diskuteres ulemper ved å innføre vårt forbedringsprosjekt på avdelingen. Dette inkluderer redusert bevissthet om ikke-medikamentelle tromboseforebyggende tiltak, fokus på dette temaet kan gå på bekostning av andre viktige satsningsområder og motstand blant ansatte mot å gjennomføre et slikt prosjekt. Til tross for de svakhetene som nå er listet opp, har vi tro på vårt forbedringstiltak nettopp fordi det er gjennomførbart og lite ressurskrevende. Vi forventer en signifikant økning i bruk av medikamentell tromboseprofylakse til de pasientene som har bruk for dette. Vi anbefaler å implementere forbedringstiltaket i første omgang som et prøveprosjekt på en sykehusavdeling. De erfaringer man så gjør seg bør legge føring for om tiltaket bør innføres på andre avdelinger, og på om det er grunn til å publisere prosjektet i for eksempel Tidsskriftet for at samme design kan prøves ved andre avdelinger

Effect on mother and child of eculizumab given before caesarean section in a patient with severe antiphospholipid syndrome

Rationale: Antiphospholipid syndrome (APS) in pregnancy may trigger the life-threatening catastrophic antiphospholipid syndrome (CAPS). Complement activation is implicated in the pathogenesis, and inhibition of complement factor C5 is suggested as an additional treatment option. Patient concerns, diagnosis and interventions: We present a pregnant patient treated with the C5-inhibitor eculizumab due to high risk of developing devastating APS-related complications. The complement inhibitory effects of the treatment were examined both in the patient and the premature infant. Outcomes: Complement activity in the mother recovered considerably faster than anticipated; however, no new thrombosis or CAPS developed during the last week of pregnancy or postpartum. Blood sampling from the umbilical vein and artery, and from the infant after delivery showed low complement activity; however, only 0.3% of the eculizumab concentration detected in the mother, consistent with low placental passage of eculizumab. Lessons: The data underscore the importance of close monitoring of complement inhibition and individualizing dosage regimens in pregnant patients receiving eculizumab. We document how traditional functional complement activity tests cannot assess the effect of eculizumab in premature infants due to the very low levels of complement factors detected in this infant born in gestational week 33. Only trace amounts of eculizumab passed the placenta. In conclusion, complement C5 inhibition might be a safe candidate treatment option for APS during pregnancy and delivery, and additionally, enables prolongation of pregnancy with important weeks. Abbreviations: APS = antiphospholipid syndrome, CAPS = catastrophic antiphospholipid syndrome, E-C5 = eculizumab-C5, EDTA = ethylenediaminetetraacetic acid, IgG = immunoglobulin G

Combined inhibition of complement and CD14 attenuates bacteria-induced inflammation in human whole blood more efficiently than antagonizing the toll-like receptor 4-MD2 complex

Background: Single inhibition of the Toll-like receptor 4 (TLR4)–MD2 complex failed in treatment of sepsis. CD14 is a coreceptor for several TLRs, including TLR4 and TLR2. The aim of this study was to investigate the effect of single TLR4-MD2 inhibition by using eritoran, compared with the effect of CD14 inhibition alone and combined with the C3 complement inhibitor compstatin (Cp40), on the bacteria-induced inflammatory response in human whole blood. Methods: Cytokines were measured by multiplex technology, and leukocyte activation markers CD11b and CD35 were measured by flow cytometry. Results: Lipopolysaccharide (LPS)–induced inflammatory markers were efficiently abolished by both anti-CD14 and eritoran. Anti-CD14 was significantly more effective than eritoran in inhibiting LPS-binding to HEK-293E cells transfected with CD14 and Escherichia coli–induced upregulation of monocyte activation markers (P E. coli–induced interleukin 6 (P E. coli (P Staphylococcus aureus (P P Conclusions: Whole bacteria–induced inflammation was inhibited more efficiently by anti-CD14 than by eritoran, particularly when combined with complement inhibition. Combined CD14 and complement inhibition may prove a promising treatment strategy for bacterial sepsis

Complement factor 5 blockade reduces porcine myocardial infarction size and improves immediate cardiac function

Inhibition of complement factor 5 (C5) reduced myocardial infarction in animal studies, while no benefit was found in clinical studies. Due to lack of cross-reactivity of clinically used C5 antibodies, different inhibitors were used in animal and clinical studies. Coversin (Ornithodoros moubata complement inhibitor, OmCI) blocks C5 cleavage and binds leukotriene B4 in humans and pigs. We hypothesized that inhibition of C5 before reperfusion will decrease infarct size and improve ventricular function in a porcine model of myocardial infarction. In pigs (sus scrofa), the left anterior descending coronary artery was occluded (40 min) and reperfused (240 min). Coversin or placebo was infused 20 min after occlusion and throughout reperfusion in 16 blindly randomized pigs. Coversin significantly reduced myocardial infarction in the area at risk by 39% (p=0.03, triphenyl tetrazolium chloride staining) and by 19% (p=0.02) using magnetic resonance imaging. The methods correlated significantly (R=0.92, p<0.01). Tissue Doppler echocardiography showed increased systolic displacement (31%, p<0.01) and increased systolic velocity (29%, p=0.01) in coversin treated pigs. Interleukin-1β in myocardial microdialysis fluid was significantly reduced (31%, p<0.05) and tissue E-selectin expression was significantly reduced (p=0.01) in the non-infarcted area at risk by coversin treatment. Coversin ablated plasma C5 activation throughout the reperfusion period and decreased myocardial C5b-9 deposition, while neither plasma nor myocardial LTB4 were significantly reduced. Coversin substantially reduced the size of infarction, improved ventricular function, and attenuated interleukin-1β and E-selectin in this porcine model by inhibiting C5. We conclude that inhibition of C5 in myocardial infarction should be reconsidered

Prevalent and immunodominant CD8 T cell epitopes are conserved in SARS-CoV-2 variants

Summary: The emergence of SARS-CoV-2 variants of concern (VOC) is driven by mutations that mediate escape from neutralizing antibodies. There is also evidence that mutations can cause loss of T cell epitopes. However, studies on viral escape from T cell immunity have been hampered by uncertain estimates of epitope prevalence. Here, we map and quantify CD8 T cell responses to SARS-CoV-2-specific minimal epitopes in blood drawn from April to June 2020 from 83 COVID-19 convalescents. Among 37 HLA ligands eluted from five prevalent alleles and an additional 86 predicted binders, we identify 29 epitopes with an immunoprevalence ranging from 3% to 100% among individuals expressing the relevant HLA allele. Mutations in VOC are reported in 10.3% of the epitopes, while 20.6% of the non-immunogenic peptides are mutated in VOC. The nine most prevalent epitopes are conserved in VOC. Thus, comprehensive mapping of epitope prevalence does not provide evidence that mutations in VOC are driven by escape of T cell immunity