Quantitative analysis of human endogenous retrovirus-K transcripts in postmortem premotor cortex fails to confirm elevated expression of HERV-K RNA in amyotrophic lateral sclerosis

Abstract Over the past two decades a number of studies have demonstrated activity of the retroviral enzyme reverse transcriptase in the serum of patients with sporadic amyotrophic lateral sclerosis (ALS). Known human exogenous retroviruses such as HIV-1 have been eliminated as possible sources of th...

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Main Authors: Jeremy A. Garson, Louise Usher, Ammar Al-Chalabi, Jim Huggett, Edmund F. Day, Adele L. McCormick
Format: Article
Language:English
Published: BMC 2019-03-01
Series:Acta Neuropathologica Communications
Subjects:
Online Access:http://link.springer.com/article/10.1186/s40478-019-0698-2
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author Jeremy A. Garson
Louise Usher
Ammar Al-Chalabi
Jim Huggett
Edmund F. Day
Adele L. McCormick
author_facet Jeremy A. Garson
Louise Usher
Ammar Al-Chalabi
Jim Huggett
Edmund F. Day
Adele L. McCormick
author_sort Jeremy A. Garson
collection DOAJ
description Abstract Over the past two decades a number of studies have demonstrated activity of the retroviral enzyme reverse transcriptase in the serum of patients with sporadic amyotrophic lateral sclerosis (ALS). Known human exogenous retroviruses such as HIV-1 have been eliminated as possible sources of this activity and investigators have therefore considered the possibility that human endogenous retroviruses (HERVs) might be involved. HERV-K (HML-2) is the most recent retroviral candidate to be proposed following the observation of elevated HERV-K expression in cortical and spinal neurons of ALS patients and the demonstration of HERV-K envelope protein neurotoxicity in vitro and in transgenic mice. This retroviral hypothesis is an attractive one, not least because it raises the possibility that ALS might become treatable using antiretroviral drugs. In the present study we have attempted independent confirmation of the observation that HERV-K RNA levels are elevated in ALS brain. Total RNA was extracted from the postmortem premotor cortex of 34 patients with ALS and 23 controls. Quantitative real-time reverse transcription PCR (RT-qPCR) was performed according to the MIQE guidelines using HERV-K gag, pol and env primer sets. Data was analysed by the 2-∆∆Ct method with normalisation against two reference genes, GAPDH and XPNPEP1. Geometric mean HERV-K RNA expression levels in the premotor cortex of ALS patients were not found to be different from the expression levels in non-ALS controls. Our findings do not confirm the recently reported association between elevated cortical HERV-K RNA levels and ALS, and thus raise doubts about the role of this endogenous retrovirus in ALS pathogenesis. The results of this study may have implications for ongoing clinical trials aiming to suppress HERV-K activity with antiretroviral drugs.
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spelling doaj.art-8a812992ed2e4731b65142f72d01d57d2022-12-22T00:41:39ZengBMCActa Neuropathologica Communications2051-59602019-03-01711910.1186/s40478-019-0698-2Quantitative analysis of human endogenous retrovirus-K transcripts in postmortem premotor cortex fails to confirm elevated expression of HERV-K RNA in amyotrophic lateral sclerosisJeremy A. Garson0Louise Usher1Ammar Al-Chalabi2Jim Huggett3Edmund F. Day4Adele L. McCormick5Division of Infection and Immunity, University College LondonSchool of Life Sciences, University of WestminsterMaurice Wohl Clinical Neuroscience Institute, King’s College LondonMolecular and Cell Biology Team, LGCSchool of Life Sciences, University of WestminsterSchool of Life Sciences, University of WestminsterAbstract Over the past two decades a number of studies have demonstrated activity of the retroviral enzyme reverse transcriptase in the serum of patients with sporadic amyotrophic lateral sclerosis (ALS). Known human exogenous retroviruses such as HIV-1 have been eliminated as possible sources of this activity and investigators have therefore considered the possibility that human endogenous retroviruses (HERVs) might be involved. HERV-K (HML-2) is the most recent retroviral candidate to be proposed following the observation of elevated HERV-K expression in cortical and spinal neurons of ALS patients and the demonstration of HERV-K envelope protein neurotoxicity in vitro and in transgenic mice. This retroviral hypothesis is an attractive one, not least because it raises the possibility that ALS might become treatable using antiretroviral drugs. In the present study we have attempted independent confirmation of the observation that HERV-K RNA levels are elevated in ALS brain. Total RNA was extracted from the postmortem premotor cortex of 34 patients with ALS and 23 controls. Quantitative real-time reverse transcription PCR (RT-qPCR) was performed according to the MIQE guidelines using HERV-K gag, pol and env primer sets. Data was analysed by the 2-∆∆Ct method with normalisation against two reference genes, GAPDH and XPNPEP1. Geometric mean HERV-K RNA expression levels in the premotor cortex of ALS patients were not found to be different from the expression levels in non-ALS controls. Our findings do not confirm the recently reported association between elevated cortical HERV-K RNA levels and ALS, and thus raise doubts about the role of this endogenous retrovirus in ALS pathogenesis. The results of this study may have implications for ongoing clinical trials aiming to suppress HERV-K activity with antiretroviral drugs.http://link.springer.com/article/10.1186/s40478-019-0698-2Amyotrophic lateral sclerosisALSHuman endogenous retrovirusHERV-KHERV-WRNA
spellingShingle Jeremy A. Garson
Louise Usher
Ammar Al-Chalabi
Jim Huggett
Edmund F. Day
Adele L. McCormick
Quantitative analysis of human endogenous retrovirus-K transcripts in postmortem premotor cortex fails to confirm elevated expression of HERV-K RNA in amyotrophic lateral sclerosis
Acta Neuropathologica Communications
Amyotrophic lateral sclerosis
ALS
Human endogenous retrovirus
HERV-K
HERV-W
RNA
title Quantitative analysis of human endogenous retrovirus-K transcripts in postmortem premotor cortex fails to confirm elevated expression of HERV-K RNA in amyotrophic lateral sclerosis
title_full Quantitative analysis of human endogenous retrovirus-K transcripts in postmortem premotor cortex fails to confirm elevated expression of HERV-K RNA in amyotrophic lateral sclerosis
title_fullStr Quantitative analysis of human endogenous retrovirus-K transcripts in postmortem premotor cortex fails to confirm elevated expression of HERV-K RNA in amyotrophic lateral sclerosis
title_full_unstemmed Quantitative analysis of human endogenous retrovirus-K transcripts in postmortem premotor cortex fails to confirm elevated expression of HERV-K RNA in amyotrophic lateral sclerosis
title_short Quantitative analysis of human endogenous retrovirus-K transcripts in postmortem premotor cortex fails to confirm elevated expression of HERV-K RNA in amyotrophic lateral sclerosis
title_sort quantitative analysis of human endogenous retrovirus k transcripts in postmortem premotor cortex fails to confirm elevated expression of herv k rna in amyotrophic lateral sclerosis
topic Amyotrophic lateral sclerosis
ALS
Human endogenous retrovirus
HERV-K
HERV-W
RNA
url http://link.springer.com/article/10.1186/s40478-019-0698-2
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