INFLUENZA, PANDEMRIX VACCINATION AND NARCOLEPSY –

A REVIEW OF SOME RECENTLY PUBLISHED LABORATORY FINDINGS

Reviewed by Anders Widell,Lund University

Note that the publication by De la Herrán-Arita AK, which is cited in several slides, contains data that have been withdrawn by the authors due to difficulties to reproduce the findings /commentary by Anders Widell November 2014

The Fear The Spanish Flu, H1N11918 killed 40-50 millions

Lethal virus then, lung effusion, still lethal today when reconstructed and given as challenge to macaques (P4 lab)

One sequela in survivors was encephalitis lethargica

Pandemia fear in the world since then

Asian Flu pandemic in 1957 (H2N2)

Hong Hong pandemic in 1968 (H3N2)

Fort Dix 1976 – more people killed by post-vaccination Guillain Barré Syndrome than by the abortive H1N1swine

outbreak itself

The 2009 pandemicWinter - Spring 2009 severe flu cases reported from

Mexico

First un-typable, then typed to H1N1pdm09 swine like

Rapid spread world wide, WHO declared pandemic

Prepared, safety–declared vaccine manufacturing platforms were adapted to include H1N1pdm09

antigens

Several manufacturers world wide.

Some added potent adjuvants, GSK used squalene AS03

However, the A(H1N1)pdm09 pandemic turned out to be milder than expecetd

Although some got very severe lung infection with deaths in immunocompromized persons and pregnant women, this pandemic killed fewer than a normal seasonal flu

The vaccination locomotive was set in motion and the vaccination campaign was highly successful and conducted in an orderly way

> 38.6 million people in EU/EEA countries were vaccinated: >30.5 million with Pandemrix,

>560,000 with Celvapan

>6.5 million with Focetria.

In Sweden, that used Pandemrix, the take up was about 60%, few adverse events

And everybody was happy ………until narcolepsy was reported in GSK Pandemrix vaccinees in Finland and Sweden

What is narcolepsy? Narcolepsy is a life long sleep disorder, due to loss of about

60.000 hypocretin (HCRT) secreting cells in the lateral hypothalamus.

Cataplexy, a sudden loss of muscle tonus following emotions

Normally starts in previously healthy persons - adolescents/ younger grown ups.

Overall incidence about 1/100.000 pyr, seasonal

Objective narcolepsy diagnosis is made either in a sleep lab or by measuring lower HCRT levels in CSF.

A certain MHCII molecule (DQA1*01:02/DQB1*06:02) is present in 98% of cases

Narcolepsy is of unknown etiology, autoimmunity suggested and streptococci have been implied

Narcolepsy outbreak 2010 An peak of narcolepsy in children in Finland and Sweden following

Pandemrix

Public outcry

A very thorough case-control investigation by ECDC released in 2012 (Vaccine Adverse Event Surveillance and Communication, VAESCO; Finland, Sweden, Norway, Denmark, UK, Holland, Italy)

Statistical increase only proven in ages 5-19 y and only after Pandemrix

South –North gradient in Sweden

In Finland, an increase in the incidence rate of narcolepsy diagnoses after September 2009 was observed with relative risk of 6.4 (95%CI 4.2-9.7).

In Sweden, an increase with a relative risk of 7.5 (95%CI 5.2–10.7)

No significant increase in other VAESCO countries

By Aug 2012 600 cases in all VAESCO countries

Was Pandemrix the only culprit?

Pilot study possibly indicating broader H1N1pdm09 exposure as initiator than Pandemrix alone (Dauvilliers et al, Sleep 33, 2010)

Increased narcolepsy incidence in Beijing China in 2010, where H1N1pdm09 vaccination was rarely used (Han el al, Ann Neurol /0; 2011)

Key study by De la Herran-Arita el al; Science Translational Med Dec 2013

Same Stanford team headed by E Mignot

As Antigen Presenting Cells these authors use MHC class I– and class II–deficient lymphoblastic T-B fusion cell line, transfected to express the mandatory DQ0602 heterodimer

Sets of peptides are added to the grove

PBMCs carrying their T Cell Receptor from patients and DQ0602 controls react with APC and peptide.

Readout as g-IFN from patient CD4 cells by ELISpot

Analyzed first 127 aa Prepro-hypocretin peptide HCRT

Locating HCRT hot spots that compete in with EBV490-503

epitope (RALLARSHVERTTDE; EBNA-1) in the DQ0602 grove.(EBV490-503 isa known binder to DQ0602)

2-logscale

Pilot study

Pattern repeated in 23 patients and in 24 DQB1*0602 concordant controls, obtained and stored at different time points

… and further strengthened in family settings

The HCRT peptides binding to the APC grove and the T-cell receptor TCR

The HCRT variants can outcompete the binding of the reference EBV peptide in the DQ0602 grove

Potential flu peptide homologs in H1N1pdm09

101 H1N1pdm09 peptides from HA1,NA1, PB1 potentially binding to DQ0602 were screened by software for the best 9-mers to bind to APC (P1,P3, P4, P6, P9) thereafter to TCR (P5, P7, P8), at positions matching the key sites found for the HCRT peptides

pHA1273-287 matched best, with three key sites P5, P7, P8 at the TCR side

There were also 3 weaker binders

The pHA1273-287 region was aligned with other H1N1 strains

Linearscale

Pre and post seasonal trivalent influenza vaccination containing H1N1pdm09 protein – in vivo findings. HCRT and pHA1275-287

Stronger findings when In vitro stimulated by the vaccine in solution

Mimicry and alignment across critical positions in the APC grove

Also the HA1 epitopes compete with the EBV reference peptides in the APC grove, strongest with HA1 2009 and HA1 1998, the latter a swine strain

Summing up T cell studies

The case for binding of the HCRT peptides into the DQ0602 grove and subsequent activation of CD4 cells is strong

Groups: Cases vs matched controls, twins, siblings

A potentially H1N1pdm09 homolog pHA1275-287 sharing 3 amino key acids binding to the TCR was found

Vaccination of Pandemrix exposed narcolepsy patients with trivalent non-adjuvated vaccine evoked a weak in vivo but a stronger in vitro response

The virus peptide may be culprit, enhanced by Pandemrix

Caveats. Relevant peptide concentrations?, special APCs, neurons do not express MHC-II

A recent antibody studyLind et al, Autoimmunity 2014

Swedish narcolepsy victims (N= 47), 80 controls

Using 35S-labelled transcription-translation products corresponding to HA1 and TRIB2 (narcolepsy related protein), radiobinding to sera was measured

Higher anti-HA antibodies were seen in narcolepsy patients, in particular the youngest

TRIB2 not generally elevated but a correlation to anti-HA, strongest in children below 13

Over