Introduction and Aims: Enveloped viruses like Ebola,
SARS, HIV and Influenza are facilitating many of their destructive
features by
shedding and secreting glycoproteins (GP). In October 2014 a
patient with a Ebola Zaire strain (EBOV) infection was treated in our
hospital. In order to reduce EBOV viral and GP load we performed
a
Lectin Affinity Plasmapheresis (LAP, first time worldwide in EVD). We
evaluated viral and GP removal by LAP.
Methods:
(1) LAP combines plasma separation with virus capture by the
unique
lectin Galanthus nivalis agglutinin (GNA), which resides in the
extracapillary spaces of the plasmafilter (see US Patent 20120037564
A1). GNA has a high affinity to GP that are universal constituents on
the surface of enveloped viruses. Because of the size restricting 200 nm
plasmafilter pores no cellular blood components get in touch with the
lectin affinity matrix. At the end of the LAP device the plasma
recombines with the blood. The Patient’s plasma never leaves the device.
The LAP device (Hemopurifier®, Aethlon Medical, San Diego, USA) was
incorporated in the arterial line upstream of the dialyzer. LAP was
performed safely on EVD day 13 (6,5 hours).
(2) Dialysis
(post-dilution CVVHDF with regional citrate anticoagulation) was
performed using a multiFiltrate Ci-Ca® device (Fresenius Medical Care
(FMC), Bad Homburg, Germany) equipped with the multiFiltrate
Ci-Ca-cassette tubing system (FMC) and the AV 1000S dialyzer (FMC).
(3)
After treatment the device was flushed with 1000 ml NaCl 0,9%, stored
in a refrigerator (4°C) for 10 days until transport to the National EBOV
Reference Laboratory at Phlipps University in Marburg, Germany. There
the LAP device was eluted according to the manufacturer’s protocol. The
eluted RNA was used for reverse transcription, and quantitative
real-time PCR. In addition eluates were centrifugated, and pellets as
well as supernatants were used for SDS gel electrophoresis followed by
western blotting with anti-GP1 (German National EBOV Reference
Laboratory, Marburg, Germany), and anti-GP2 (Filovirus Laboratory,
INSERM U758, ENS Lyon, France) antibodies.
Results:
The LAP device was easily integrated into the extracorporeal circuit.
LAP was performed safely (no hemolysis, no clotting or anaphylactic
reaction). As shown by western blots circulating GP was removed in
addtion to the
elimination of 253.160.000 EBOV copies. The
EBOV-IgG-titer did further increase after the LAP treatment, and
viral
load measurements during the treatment phase did show a
3-fold decrease.
After EVD day 13 the patient did improve steadily and finally fully
recovered.
Conclusions: Our data provide a proof
of concept for important supportive Ebola GP and virus capture and
warrant further examination of LAP. Reduction of viral load and GP maybe
benefical in all diseases caused by enveloped viruses.
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