In support of the World Health Organisation’s (WHO) response to the Ebola crisis, NIBSC has fast tracked the development and production of 5 reference reagents for use in the calibration of polymerase chain reaction (PCR) and serological assays.
All 5 reference reagents are now endorsed by the WHO’s Expert Committee on Biological Standardisation (ECBS) and are available for ordering by laboratories. Due to the expected high demand, orders for some reagents will be restricted.
The availability of the 4 Ebola virus Zaire RNA reference reagents is critical for accurate detection of Ebola nucleic acid by polymerase chain reaction to confirm an individual’s infection status which is vital to consequent appropriate healthcare provision.
The anti-Ebola reference reagent for serology assays will facilitate the standardisation of Ebola methods used in epidemiological studies to measure past or present Ebola virus disease and in clinical trials of candidate vaccines and immune therapies to measure antibodies in humans.
The suitability of the reference reagents was confirmed through an international collaborative study involving participating laboratories from the UK, USA, Europe, Australia and China.
The diagnostic reagents and vaccine reagent are available to order through the NIBSC website.
These materials are freeze-dried formulations derived from non-infectious HIV-1-like particles incorporating a lentiviral vector (LVV) in which the HIV-1 genes have been substituted with EBOV 2014 genes. Two different LVV constructs have been developed, one containing NP, VP35 and GP genes (NP-VP35-GP-LVV) and one containing the VP40 and L genes (VP40-L-LVV). The EBOV RNA is packaged inside the lentiviral particles and therefore the synthetic Ebola RNA references must be extracted prior to amplification. The synthetic Ebola RNA references have been established by the WHO ECBS.
EBOV RNA NP-VP35-GP WHO Reference Reagent (NIBSC code 15/222), with an assigned potency of 7.5 Log10 units/mL when reconstituted in 1 mL of nuclease-free water, is intended to be used for the calibration of secondary references for RT-PCR assays targeting Ebola virus NP, VP35 or GP gene sequences.
EBOV RNA VP40-L WHO Reference Reagent (NIBSC code 15/224), with an assigned potency of 7.7 Log10 units/mL when reconstituted in 1 mL of nuclease-free water, is intended to be used for the calibration of secondary references for RT-PCR assays targeting the Ebola VP40 or L gene sequences.
Corresponding low-positive in-run controls for monitoring the analytical sensitivity of these assays are also available (NIBSC codes 15/136 and 15/138).
Anti-EBOV plasma, human WHO Reference Reagent (NIBSC code 15/220) has been established by the WHO ECBS for use in neutralisation, pseudotype neutralisation and enzyme immune assays with an assigned unitage of 1 unit/mL. 15/220 is liquid, filled in 0.1 mL aliquots into 2 mL Sarstedt screw-capped tubes and should be stored at -20⁰C or below.
The source material is plasma obtained from a single donor recovered from Ebola virus disease and repeatedly tested negative for Ebola virus RNA. Prior to receipt at NIBSC, the convalescent plasma was held at Public Health England, Colindale, UK until re-confirmed by PCR that no Ebola RNA could be detected in the material. At NIBSC, the convalescent plasma was solvent/detergent treated using a method validated at NIBSC for the inactivation of HIV-1 IIIB spiked into plasma.
See press release for more information.