Immune history and seasonal influenza virus...

Immune history and seasonal influenza

virus susceptibility

Scott E. Hensley

Harris et. al. PNAS (2006) 50:19123

Influenza virus

head

stalk

Hemagglutinin

slide borrowed from Subbarao1918

H1N1Spanish

Flu

201719681957

H2N2Asian

Flu

H3N2Hong Kong

Flu

1977

H1N1Russian

Flu

2009

H1N1Swine

Flu

Humans are constantly exposed to new flu strains

today

HA evolution

image from:

Trevor Bedford

http://bedford.io

It takes a long time to make influenza vaccines

and they are not very effective

There is something magical about childhood

Bodewes et al. CVI 2011

We are all exposed to flu during childhood

H1N1

H3N2

H1N1 or H3N2

Early childhood flu exposures leave lifelong

immunological imprints

Kurosaki et al, NRI 2015

slide borrowed from Subbarao1918

H1N1Spanish

Flu

201419681957

H2N2Asian

Flu

H3N2Hong Kong

Flu

1977

H1N1Russian

Flu

2009

H1N1Swine

Flu

Depending on our year of birth,

we all have different immunological imprints!

2009 pH1N1

HA

2009 pH1N1

HA

Childhood imprinting shapes specificity of

influenza virus antibody responses

2009 pH1N1

HA

Previous HA

X

2009 pH1N1

HA1983 H1N1

HA

2009 pH1N1

HA

2009 pH1N1

HA1952 H1N1

HA

Childhood imprinting shapes specificity of

influenza virus antibody responses

An example of immune-focusing on a viral

epitope encountered in childhood

+

1983 2009

Li et al. JEM 2013

Linderman et al. PNAS 2014

Petrie et al. JID 2016

=

focused Ab response

Residue 166

The 2009 H1N1 virus acquired a mutation in an

epitope recognized by ‘middle-aged’ individuals

Linderman et al., PNAS 2014

0

5

10

15

% P

CR

-co

nfirm

ed

in

fecte

d

15/202

0/139

5/41

A/Cal/7/09-WT - + +A/Cal/7/09-K166Q - + -

p < 0.05

p < 0.05

ns

Many ‘middle-aged’ individuals were susceptible

to drifted H1N1 strain in 2013-14 season

• 382 humans bled prior to

2013-2014 season

• 20 of these individuals

were naturally infected with

H1N1 (PCR-confirmed)

• Did these 20 people have

pre-season antibody titers

against vaccine strain, but

not the circulating strain?

Petrie et al. Journal of Infectious Disease (2016)

Previous HA

X

2009 pH1N1

HA1983 H1N1

HA

2009 pH1N1

HA

2009 pH1N1

HA1952 H1N1

HA

*

*

*

Childhood imprinting affects seasonal influenza

virus susceptibility

The H3N2 vaccine has only been effective in very

young individuals over the past 2 years

www.cdc.gov/vaccines/acip/meetings

<195

2

1953

-196

7

1968

-199

9

2000

-200

8

2009

-201

80

20

40

60

YOB

va

ccin

e e

ffective

ne

ss (%

)

2017-2018

Is childhood

imprinting involved?

Contemporary H3N2 strains possess new

glycosylation site in HA

Zost et al. PNAS (2017)

The problem of egg adaptation

A/Hong Kong/4801/2014 A/Hong Kong/4801/2014

#X263

T160 HA K160 HA

Glycosylation

matches circulating

strains

No antigenic site B

glycosylation

Zost et al. PNAS (2017)

Abs from ferrets infected with current H3N2

vaccine strain poorly recognize circulating H3N2

Zost et al. PNAS (2017)

What about humans?

Human influenza vaccine antigens are prepared in

eggs, cell culture, and via baculovirus system

T160 HAK160 HA K160 HA

Abs elicited by Flublok (baculovirus antigen)

neutralize current circulating H3N2 strain

T160 HA K160 HA K160 HA T160 HA K160 HA K160 HA

Zost et al. PNAS (2017)

But why does the current H3N2 vaccine have such

low VE in everyone except very young kids?

<195

2

1953

-196

7

1968

-199

9

2000

-200

8

2009

-201

80

20

40

60

YOB

va

ccin

e e

ffective

ne

ss (%

)

2017-2018

1968 1978 1988 1998 2008 20180

20

40

60

80

100

year

fre

qu

en

cy (%

)

residue 160 identity

T

K

Hypothesis: egg-adapted H3 strain (that

has K160 HA) recalled memory B cells in

older children that were primed by H3N2

viruses that had K160 HA

Prevax Ab repertoire Postvax Ab repertoireVaccine Antigen

Individual 1

Individual 2

Low neutralizing Ab titer against

glycosylated strain

Higher neutralizing Ab titer against

glycosylated strain

-Recognizes epitope blocked by glycan

-Recognizes epitope not blocked by glycan

Summary of the past two H3N2 seasons

baculovirus HA

egg-grown HA

Can we make better influenza vaccines?

• Universal influenza vaccines based on HA stalk immunity

• mRNA-based influenza vaccines

Harris et. al. PNAS (2006) 50:19123

Influenza virus

head

stalk

Hemagglutinin

HA head versus HA stalk Abs

Wrammert et. al, JEM 2011

HA stalk Abs are not as great as HA head Abs

(but they protect against many viral strains)

pH1N1

stalk

mAb

pH1N1

head

mAb

Household Cohort Hospitalization Cohort

Donors

373 healthy individuals

enrolled prior to the flu

season (both 2013-14

& 2015-16)

184 patients hospitalized

with severe respiratory

illness symptoms were

enrolled upon admission

InfectionNaturally acquired

pH1N1 infection

Hospitalization with

naturally acquired pH1N1

infection

SeraSera obtained prior to

the season

Sera obtained upon

hospital admission

MonitoringInfluenza infection

confirmed via PCR

Influenza infection

confirmed via PCR

Are HA stalk Abs associated with protection in

humans?

Household Cohort Hospitalization Cohort

Donors

373 healthy individuals

enrolled prior to the flu

season (both 2013-14

& 2015-16)

184 patients hospitalized

with severe respiratory

illness symptoms were

enrolled upon admission

InfectionNaturally acquired

pH1N1 infection

Hospitalization with

naturally acquired pH1N1

infection

SeraSera obtained prior to

the season

Sera obtained upon

hospital admission

MonitoringInfluenza infection

confirmed via PCR

Influenza infection

confirmed via PCR

Are HA stalk Abs associated with protection in

humans?

Uninfected Infected

5

10

20

40

80

160

320

640

HA

I ti

ter

an

ti-C

al

<10Total=361 Total=12

Uninfected Infected

*

p < 0.05

HI negativeHI positive

Fisher’s exact test

HAI lowH1N

1 H

AI

tite

r

Head antibody titers

HAIlow

HAIhigh

HAI high

Barbour et al. manuscript in prep

HA head Abs are associated with protection in

the 2015-16 ‘household’ study

Uninfected Infected

50

100

200

400

799.999999999999

1600

Recip

rocal c6/1

tit

er

<100

800

n = 25 n = 12

Stalk antibodies in HAIlow subset

Sta

lk a

nti

bo

dy t

iter

(recip

rocal c6/1

tit

er)

Logistic regression of log2(titer)

p =0.568, odds ratio = 0.85

HA stalk Abs are not associated with protection

in the 2015-16 ‘household’ study

Barbour et al. manuscript in prep

Household Cohort Hospitalization Cohort

Donors

373 healthy individuals

enrolled prior to the flu

season (both 2013-14

& 2015-16)

184 patients hospitalized

with severe respiratory

illness symptoms were

enrolled upon admission

InfectionNaturally acquired

pH1N1 infection

Hospitalization with

naturally acquired pH1N1

infection

SeraSera obtained prior to

the season

Sera obtained upon

hospital admission

MonitoringInfluenza infection

confirmed via PCR

Influenza infection

confirmed via PCR

Are HA stalk Abs associated with protection in

humans?

Uninfected Infected

5

10

20

40

80

160

320

640

1280

2560

HA

I ti

ter

an

ti-C

al

<10

HI negativeHI positive

HAI high

HAI low

Total=64Total=120

HI negative

HI positive

Infected Uninfected

**

p = 0.0026

Head antibody titers

H1N

1 H

AI

tite

r

HAIlow

HAIhigh

Fisher’s exact test

Non-flu infected Flu infected

Non-flu infected Flu infected

HA head Abs are associated with protection in

the 2015-16 ‘hospitalization’ study

Barbour et al. manuscript in prep

Uninfected Infected

50

100

200

400

799.999999999999

1600

3200

Recip

rocal c6/1

tit

er

800

<100

Stalk antibodies in HAIlow subset

n = 43 n = 39

Sta

lk a

nti

bo

dy t

iter

(recip

rocal c6/1

tit

er)

Logistic regression of log2(titer)

p =0.146, odds ratio = 1.22

Non-flu infected Flu infected

HA stalk Abs are not associated with protection

in the 2015-16 ‘hospitalization’ study

Barbour et al. manuscript in prep

HA stalk Abs are not independently associated with

protection in the 2015-16 ‘hospitalization’ study

Uninf

ecte

d

Infe

cted

0.03125

0.0625

0.125

0.25

0.5

1

2

4

8

ug/m

l equiv

ilant

(Rela

tive to C

R9114)

HA stalk-based vaccines will need to elicit high

levels of Abs

Uninf

ecte

d

Infe

cted

0.031250.06250.1250.250.5

1248

163264

128256512

1024

ug/m

l equiv

ilant

(Rela

tive to C

R9114)

same data

level required for

mouse protection

5’ cap1

+ HPLC purification

HA coding sequence

+ Nucleoside modification

ribose

Uridine

ribose

1-Methyl-

pseudouridine

N

Nucleoside-modified, purified mRNA formulated in LNP is

highly expressed and stimulates potent immune responses.

PAMPs

dsRNA

ssRNA

mRNA: the influenza vaccine of the future

mRNA-based ZIKV vaccine protects

rhesus macaques

Pardi et al. Nature 2017

0 100 200 300 400

5

20

80

320

1280

5120

20480

time (days post-vaccination)

HA

I tite

r

mRNA-irrelevant antigen

mRNA-HA

conventional vaccine

mRNA vaccine elicits a long-lasting antibody

response

Pardi et al. unpublished

mRNA vaccine elicits a protective immune

response

Pardi et al. unpublished

0 5 10 15 200

50

100

days post-infection

surv

ival (

%)

survival

mRNA-irrelevant antigen

mRNA-HAconventional vaccine

0 2 4 6 8 10 12 14 16 18 20 2250

60

70

80

90

100

110

days post-infection

% in

itial w

eig

ht

weight loss

mRNA-irrelevant antigen

mRNA-HAconventional vaccine

12825

651

2

1024

2048

4096

8192

1638

4

3276

80.0

0.5

1.0

1.5

2.0

sera dilution

O.D

. (4

05 n

m)

HA stalk Abs(H6 head/H1 stalk)

mRNA-HA

mRNA-irrelevant antigen

12825

651

2

1024

2048

4096

8192

1638

4

3276

80.0

0.5

1.0

1.5

2.0

sera dilution

O.D

. (4

05 n

m)

total HA Abs(H1 head/H1 stalk)

mRNA-HA

mRNA-irrelevant antigen

mRNA vaccine elicits HA head and HA stalk Abs

Krammer and Palese,

Nature Reviews 2015Pardi et al. unpublished

weight

0 2 4 6 8 10 12 14 1650

60

70

80

90

100

110

days post-infection

% s

tart

ing w

eig

ht

mRNA-A/California/7/09 HA

mRNA-irrelevant antigen

mRNA vaccine protects against homologous and

drifted influenza virus strains

Pardi et al. unpublished

homologous challenge

(A/Cal/07/09)weight

0 2 4 6 8 10 12 14 1650

60

70

80

90

100

110

days post-infection

% s

tart

ing w

eig

ht

mRNA-A/California/7/09 HA

mRNA-irrelevant antigen

drifted challenge

(A/PR/8/34)

• Early childhood immunological imprints shape the specificity of

antibody responses against new influenza virus strains

– This is clearly the case with H1N1 viruses

– This appears to be the case with H3N2 viruses

• Egg-adaptive mutations likely led to low vaccine effectiveness

last year

• HA stalk Abs are not at sufficiently high levels in most

individuals to protect against seasonal influenza virus

• mRNA vaccines might be a good alternative to conventional

influenza vaccines—it is unclear why they elicit such high

levels of Abs

Main points

Acknowledgements

Tyler Garretson

Theresa Eilola

Sigrid Gouma

Seth Zost

Elinor Willis

Amy Davis

Kaela Parkhouse

Shannon Barbour

Megan Gumina

Claudia Arevalo

Yang Li

Susi Linderman

Ben Chambers

Collaborators

Drew Weissman—U. Penn

Sara Cobey—U. of Chicago

Arnold Monto -- U. Michigan

Josh Petrie -- U. Michigan

Emily Toth Martin-- U. Michigan

Aubree Gordon-- U. Michigan

Patrick Wilson -- U. of Chicago

John Treanor -- U. of Rochester

Jesse Bloom – Fred Hutch

Florian Krammer – Mt Sinai