Pathogen-reduced Ebola virus convalescent plasma: first steps towards standardization of manufacturing and quality control including assessment of Ebola-specific neutralizing antibodies

BACKGROUND

Ebola virus disease is a public health emergency of international concern, and enormous efforts are being made in the development of vaccines and therapies. Ebola virus convalescent plasma is a promising anti-infective treatment of Ebola virus disease. Therefore, we developed and implemented a pathogen-reduced Ebola virus convalescent plasma concept in accordance with national, European and global regulatory framework.

MATERIALS AND METHODS

Ebola virus convalescent plasma manufacture and distribution was managed by a collection centre, two medical centres and an expert group from the European Blood Alliance. Ebola virus convalescent plasma was collected twice with an interval of 61 days from a donor recovering from Ebola virus disease in Germany. After pathogen reduction, the plasma was analysed for Ebola virus-specific immunoglobulin G (IgG) antibodies and its Ebola virus neutralizing activity.

RESULTS

Convalescent plasma could be collected without adverse events. Anti-Ebola virus IgG titres and Ebola-specific neutralizing antibodies in convalescent plasma were only slightly reduced after pathogen reduction treatment with S59 amotosalen/UVA. A patient in Italy with Ebola virus disease was treated with convalescent plasma without apparent adverse effects.

DISCUSSION

As proof of principle, we describe a concept and practical implementation of pathogen-reduced Ebola virus convalescent plasma manufacture, quality control and its clinical application to an Ebola virus disease patient.

[Anticoagulation during pregnancy following an artificial heart valve replacement]

HISTORY AND CLINICAL FINDINGS

A 23-year-old woman had received a mechanical bileaflet mitral valve prosthesis because of severe mitral valve insufficiency caused by an acute bacterial endocarditis with vegetations. One year after the operation the patient suffered on two miscarriages under oral anticoagulation by phenprocoumon. Present, she was referred to our center with the question of conversion to low molecular weight heparine because of continued yearning for a baby.

INVESTIGATIONS

At admission the woman was in good general and nutritional condition. Echocardiography showed a regular prosthetic function. Blood analysis, electrolyte parameters and enzyme values were normal, further laboratory investigations revealed a factor-V-Leiden-mutation. A chromosomal analysis detected no aberrations.

TREATMENT AND COURSE

The oral anticoagulation by phenprocoumon was switched to subcutaneous low molecular weight heparine in therapeutical dosage. Anti-factor-Xa-activity was controlled at regular intervals. Further pregnancy was uneventful for both, mother and child. A healthy infant was born by caesarean section at 40 (th) week of gestation.

CONCLUSIONS

Treatment with anticoagulation by phenprocoumon is indispensable for mechanical heart valve protheses. Conversion to low molecular weight heparine is possible in patients who insistent request to conceive. The anticoagulation by low molecular weight heparine avoids teratogenic effects during pregnancy because the placenta is impermeable to that heparin. Furthermore, prophylaxis of thromoses by low molecular weight heparine is probably in almost the same manner as by phenprocoumon.

Congenital Coronary Artery Fistula Draining Into the Right Ventricle: Successful Surgical Closure After Failed Transcatheter Coil Embolization

Coronary artery aneurysms and fistulae are very rare congenital anomalies. They occur in 0.2-0.4 % of all congenital heart diseases. In this article, we report a case of a four-year-old girl with a right coronary artery aneurysm and fistula draining into the right ventricle. Since the transcatheter coil embolization was not successful, surgical occlusion was considered in this case. We describe and discuss the handling of the fistula and the aneurysmatic enlargement of the proximal coronary artery.

Impella Recover 100: successful perioperative support for off pump coronary artery bypass grafting surgery in a patient with end-stage ischemic cardiomyopathy

The authors present the successful use of the Impella recover 100 intracardiac left ventricular assist device in a 55-year old man suffering from end-stage ischemic cardiomyopathy. The pump was implanted preoff pump coronary artery bypass grafting (OPCAB) and it was successfully weaned 5 days postoperatively. In addition, an intra-aortic balloon pump (IABP) was implanted to convert the non-pulsatile flow of the Impella into a pulsatile flow. In this paper benefits and risks of this technique are shown.

The Impella Recover microaxial left ventricular assist device reduces mortality for postcardiotomy failure: a three-center experience

BACKGROUND

We evaluated patient outcomes and complications associated with the microaxial Impella Recover left ventricular assist device (Impella Cardiosystems AG, Aachen, Germany) for postcardiotomy low-output syndrome. This low-cost device is inserted across the aortic valve through a 10-mm vascular graft sewn to the ascending aorta.

METHODS

Impella patients were compared with 198 patients treated with an intraoperative intra-aortic balloon pump between January 2000 and December 2002. Three risk scores were used: the Hausmann score, the Texas Heart Institute score, and the Cleveland intensive care unit score. Between September 2001 and March 2003, 24 patients were treated with the Impella Recover for low-output syndrome. Before device insertion, 21 could not be separated from cardiopulmonary bypass, and 3 had postoperative hemodynamic instability despite high-dose catecholamines. Sixteen were treated with the Impella and intra-aortic balloon pump and 8 with the Impella alone (no intra-aortic balloon pump because of peripheral vascular disease or because deemed unnecessary).

RESULTS

No technical problems with device insertion occurred. Pump flow was 3.3 +/- 0.7 L/min at 28,000 +/- 4500 RPM. Support time was 61 +/- 56 hours (range, 7-228 hours). Four devices required repositioning. One device failed (leaking purge line) and was removed. Hemolysis was minimal (lactate dehydrogenase levels of 540 +/- 260 U/dL for Impella survivors). Mortality for Impella patients was 54% (13/24), similar to that for high-risk intra-aortic balloon pump patients (Hausmann score > or =2 [57%], intensive care unit score > or =2 [51%], Texas Heart Institute score > or =0.75 [55%], and cardiac index < or =2.3 [45%]). Cardiac output data were available in 19 Impella patients. Impella patients able to increase their cardiac output to 1 L/min or more above the pump flow of the Impella Recover had a 10% (1/10) mortality, versus 88% (8/9) in patients with a residual cardiac function of 1 L/min or less (P =.001). Comparison of high-risk intra-aortic balloon pump patients with Impella patients with residual cardiac function of 1 L/min or more showed a significant reduction in mortality, regardless of the high-risk definition used. Residual cardiac function was the strongest predictor of survival in Impella patients.

CONCLUSIONS

The Impella Recover device provides 3 to 4 L/min flow. It improves survival in patients with low-output syndrome if the heart is able to pump 1 L/min or more above device flow.

Late Pulmonary Valve Replacement after Correction of Fallot's Tetralogy

BACKGROUND

The aim of this study was to investigate necessity and outcome of late pulmonary valve replacement (PVR) after repair of tetralogy of Fallot (TOF).

METHODS

Hospital records from patients operated on for TOF at our institution between 1960 and 2002 were reviewed and patients were interviewed by questionnaires.

RESULTS

Out of 411 long-term survivors after TOF-repair, 47 (11.4 %) patients required reoperation after 13.2 +/- 7.4 years. Preoperative right ventricular (RV) dilatation was present in 36 (76.6 %) patients including 16 (34 %) with impaired RV function. Isolated PVR was performed in 12 patients (25.5 %). Additional procedures were necessary in 35 patients (74.5 %), including closure of residual defects (VSD, n = 11), tricuspid valve replacement (n = 1) and repair (n = 3). Obstructive right ventricular or pulmonary artery lesions (34 patients, 72.3 %) were all surgically addressed. RV pressure decreased from 61.1 +/- 27.7 to 42.9 +/- 13.3 mm Hg (p < 0.01) after PVR. RV size was reduced and RV function improved compared to preoperative values. Early mortality after reoperation was 2.1 % (n = 1) with one patient dying from biventricular failure. There was no late mortality.

CONCLUSIONS

PVR after Fallot repair is frequently required because of progressive RV enlargement with dysfunction. It can be performed with relatively low risk, even in the setting of multiple reoperation. Obstructive lesions (RVOTO, PA stenosis) and residual defects are frequently observed in patients needing late PVR and may play a crucial role in the development of RV failure. Timely valve replacement with repair of all obstructive lesions proximal and distal to the implanted valve is the key to preserving RV function.

[Neuropeptide release in the dura mater encephali in response to nitric oxide--relevance for the development of vascular headaches?]

Nitric oxide (NO) and calcitonin gene-related peptide (CGRP), potent vasodilators in the meninges,may be involved in the pathophysiology of vascular headaches such as migraine pain. NO donators can provoke headache attacks in migraineurs and increased levels of CGRP have been found in the venous outflow from the head during migraine attacks. We therefore examined the effect of both NO and CGRP on dural blood, a process which may parallel nociceptive processes in the meninges. 1. Arterial blood flow was measured in the exposed dura mater encephali of the rat using laser Doppler flowmetry. Local application of different NO donors (SNAP,NONOate, and NOC-12) caused dose-dependent increases in meningeal blood flow. CGRP(8-37) at 10(-4) M did not significantly change the basal flow but attenuated increases in blood flow caused by the NO donors at concentrations of 10(-5)-10(-3) M.2. In another series of experiments, the hemisected skulls of adult Wistar rats, complete with intact dura mater, were filled with oxygenated synthetic interstitial fluid (SIF) and the CGRP content of this fluid was assessed every 5 min. When the NO donator NONOate, at concentrations of 10(-5)-10(-3) M, was added to the SIF, or when the SIF was bubbled with NO gas (1000 ppm in N(2) atmosphere) instead of carbogen, CGRP release increased in a concentration-dependent manner. We conclude that the vasodilatory effect of NO that causes increased meningeal blood flow is in part the result of both stimulating the release of CGRP and promoting the vasodilatory action of CGRP. Since NO donors such as nitroglycerin are known to provoke headache and CGRP is released during migraine pain, the NO-stimulated CGRP release may be relevant for the development of vascular headaches that are accompanied by meningeal hyperaemia.

Increase in meningeal blood flow by nitric oxide--interaction with calcitonin gene-related peptide receptor and prostaglandin synthesis inhibition

This study addresses possible interactions of the vasodilators nitric oxide (NO), calcitonin gene-related peptide (CGRP) and prostaglandins, which may be implicated in the generation of vascular headaches. Local application of the NO donator diethylamine-NONOate (NONOate) to the exposed dura mater encephali of the rat caused dose-dependent increases in meningeal blood flow recorded by laser Doppler flowmetry. Pre-application of the CGRP receptor antagonist CGRP8-37 significantly attenuated the evoked blood flow increases, while the cyclooxygenase inhibitors acetylsalicylic acid and metamizol were only marginally effective. Stimulation of rat dura mater with NONOate in vitro caused increases in CGRP release. NADPH-diaphorase activity indicating NO production was restricted to the endothelium of dural arterial vessels. We conclude that increases in meningeal blood flow caused by NO depend partly on the release and vasodilatory action of CGRP from dural afferents, while prostaglandins are not significantly involved.

Redistribution of K+ channels into dendrites is unlikely to account for developmental down regulation of A-currents in rat dentate gyrus granule cells

The electrical reactions of many central neurons depend on two voltage-activated K+ currents: the fast transient A-current IA and the delayed rectifier current IK. In rat dentate gyrus granule cells, the A-current density decreases during ontogenesis, possibly due to a redistribution of K+ channels from somata into dendrites. We tested this possibility in mechanically isolated granule cells with preserved dendrites of different length. Potassium currents were recorded with the whole-cell patch-clamp technique using prepulse protocols with and without a delay interval to isolate IA. A correlation between the length of the dendrites and the amount of A-current expressed in a given cell could not be demonstrated. Our findings therefore confirm an ontogenetic down regulation of A-currents.

Recognition of restenosis: can patients be defined in whom the exercise-ECG result makes angiographic restudy unnecessary?

The value of exercise ECG in predicting the occurrence of restenosis after successful transluminal coronary angioplasty (PTCA) was investigated in 398 patients with exercise tests of comparable workload before, immediately after and within 6 months after PTCA. In patients with normalized exercise ECG (n = 166) restenosis was observed in 16.3% and indication for repeat PTCA was present in 6.6%. RePTCA was recommended in only 3.2% of patients if the exercise test was still normal at restudy and if the patients were free of anginal symptoms. In patients with a renewed ST-segment depression (n = 77) the rate of restenosis was 67.5% and the indication for rePTCA was present in 52%. In patients without changes in the exercise tests before and after PTCA and at restudy (n = 155) restenosis was seen in 25.8% and rePTCA was recommended in 14.2%. It is concluded that from the clinical point of view, in patients with improved exercise ECG at restudy, especially if they are free of angina, there is no need for a re-angiogram because indications for rePTCA are very rare.