Vaccine design for respiratory viruses

Mahidol UniversityJune 2016

The respiratory tract in mucosal infection and vaccination

Seminar outline

- current state of vaccines for resp pathogens

- influenza

- RSV

- other respiratory pathogens

The respiratory tract in mucosal infection and vaccination

Seminar outline

- current state of vaccines for resp pathogens

- influenza

- RSV

- other respiratory pathogens

Location Common pathogens

Nasopharynx RhinovirusesCoronaviruses

Oropharynx AdenovirusesEpstein-Barr Virus

Larynx-trachea Parainfluenzaviruses

Bronchi Influenzaviruses

Bronchioles Respiratory Syncytial Virus (RSV), SARS

Alveoli Influenza, RSV, Parainfluenza, SARS

Virus Infections of the Respiratory Tract

The importance of vaccines

Leading causes of death worldwide

http://www.who.int/mediacentre/factsheets/fs310/en/

Vaccines against respiratory pathogensPathogen Current vaccine Route Mucosal vaccine

ViralRSV none - in dev (candidate MEDI-534)Influenza inactivated, split; IM IM live atten FluMistParainfluenza none - in dev (candidate MEDI-534)SARS none - desirable

BacterialM. tuberculosis live atten M. bovis, BCG ID in devB. pertussis acellular, DTaP IM in devS. pneumoniae conj polysacc, PPV, CPV, PBPV IM in devH. influenzae conj polysacc, Hib IM in devB. Anthracis cell-free filtrate, AVA+alum IM in dev

Respiratory transmissionMeasles live atten; MMR IM -Mumps live atten; MMR IM -Rubella live atten; MMR IM -Varicella-zoster live atten; Varilrix, Varivax, IM -

MMRV

The respiratory tract in mucosal infection and vaccination

Seminar outline

- current state of vaccines for resp pathogens

- influenza

- RSV

- other respiratory pathogens

Influenza3 main serotypes A, B and CA (and B) most important for humans

Influenza viruses

Influenza virus strains in pigs & humans

Emerg Infect Dis 20, 6 [2014]

Salomon and Webster [2009] Cell 6, 402

"Cytokine storm" in influenza pathogenesis

potentially fatal immune reaction consisting of a positive feedback loop between cytokines and immune cells, with highly elevated levels of various cytokines

highly pathogenic influenza strains trigger higherproinflammatory cytokine production than lesspathogenic strains- TNF- CCL5 (RANTES)- CCL3 (MIP1α) - CCL4 (MIP1β)- CCL2 (MCP-1)

• traditionally formalin-inactivated, egg-grown virus

• constant surveillance

• trivalent vaccine:A (H1N1)A (H3N2)B strain

• live attenuated (nasal) available as of 2003

Influenza vaccines

“weak spots” Science [2006] 312, 380(conserved M2 and NP proteins)

Influenza vaccines

suppresses type 1 IFN production by:PKR interferenceblocking activation of NFkB, AP-1, IEF3 and IRF7

reduces DC maturation, migration and T cell stimulation by inhibiting production of cytokines (MIP-1β, IL-12, RANTES,IL-8, IFN-γ, CCR7 (Fernandez-Sesma J Virol 80, 6295 [2006])

H3N2 NS1 acts as H3 histone mimic which modulates hosttranscription (Nature [2012] 483, 428)

Immune modulatory activities of Influenza NS1

Interference of IFN signalling by flu NS1

Hale et al [2010] Future Microbiol 5, 23

• traditionally formalin-inactivated, egg-grown virus

• constant surveillance

• trivalent vaccine:A (H1N1)A (H3N2)B strain

• live attenuated (nasal) available as of 2003

Influenza vaccines

The respiratory tract in mucosal infection and vaccination

Seminar outline

- current state of vaccines for resp pathogens

- influenza

- RSV

- other respiratory pathogens

Respiratory syncytial virus (RSV)

• Leading cause of pneumonia and bronchiolitis in infants

• Yearly hospitalization costs in the $100 millions

• Hospitalization due to lung inflammation

• No vaccine available (inflammatory side-effects)

Formalin RSV vaccine in 1960s:• poorly protective• poor induction of neutralizing antibodies• primed for lung inflammation w neutrophils and eosinophils• mouse studies indicate Th2 response w eosinophils

Current vaccine research aims to:• increase protection (Ab or CTL)• avoid inflammatory (Th2) response

Why is an RSV vaccine so elusive?

- binds CX3CR (fraktalkine receptor) - contains Th cell epitope

- binds TLR4

- blocks TNF signaling

G

F

SH

Immunological activities of RSV glycoproteins

- Interference with type I IFN signalingNS1 and NS2 proteins degrade STAT2, block Tc activation

- Interference with TNF signalingSH protein

- Interference with leukocyte chemotaxisG protein CX3CR-binding motif

- tilting Th1/Th2 balanceG protein Th cell epitope

- TLR4 interaction/signalingF protein

Summary of RSV immune evasive strategies

Th1 Th2Protective Non-protective

Non-inflammatory Inflammatory

Cytokines: Cytokines:

IFN-γ IL-4, IL-5, IL-10, IL-13

Search for an RSV vaccine(a question of balance)

Th1 Th2Protective Non-protective

Non-inflammatory Inflammatory

Cytokines: Cytokines:

IFN-γ IL-4, IL-5, IL-10, IL-13

Search for an RSV vaccine(a question of balance)

Th1 Th2Protective Non-protective

Non-inflammatory Inflammatory

Cytokines: Cytokines:

IFN-γ IL-4, IL-5, IL-10, IL-13

Search for an RSV vaccine (a question of balance)

RSV and asthma

modified from Busse et al [2010] Lancet 376, 826

Th2 immune response in asthma

RSV and asthma

Wu & Harter [2011] Exp Rev Anti Infect Ther 9, 731

How can we improve the design of vaccines and/or therapeutics?

• Selective modification of viral epitopes to make safer, more effective vaccines

• Anti-cytokine or chemokine therapy- anti cyokine, chemokine antibodies- use vaccine adjuvants which favour selective

cytokine/chemokine profiles

B cell TCytotoxic cell THelper cell

MHC-I MHC-II

BCR TCR TCR

Antibodies Lysis of virus-infectedcells

Facilitates and amplifiesmultiple immune responses

Epitope presentation to lymphocytes

RSV G-Protein

1 100 200 298Signal/ anchor

Th epitope (aa185-193)Sparer et al [1998]Tebbey et al [1998]Varga et al [2000]

128 229

Bacterially expressed Trx-G

Th epitope (aa185-193)Sparer et al [1998]Tebbey et al [1998]Varga et al [2000]

128 229Trx

Immunization/challenge Protocol

Immunize mice 2xsubcutaneously w Trx-G + Adjuvant

Inoculate RSV intranasally

LUNGS• Virus Titers • Inflammatory cells• Cytokines

4 days

14 days

0

20

40

60

80

100

120

PBS

I185

A

C18

6A

K18

7A

R18

8A

I189

A

P190

A

N19

1A

K19

2A

K19

3A wt

RSV

tite

r (re

lativ

e to

con

trol)

0

5

10

15

20

25

30

PBS

I185

A

C18

6A

K18

7A

R18

8A

I189

A

P190

A

N19

1A

K19

2A

K19

3A wt

% B

AL

Cells

RSV

tite

rEo

sino

phili

a

Protection vs eosinophilia for Trx-G mutant vaccines

0

20

40

60

80

100

120

PBS

I185

A

C18

6A

K18

7A

R18

8A

I189

A

P190

A

N19

1A

K19

2A

K19

3A wtR

SV ti

ter (

rela

tive

to c

ontro

l)

0

5

10

15

20

25

30

PBS

I185

A

C18

6A

K18

7A

R18

8A

I189

A

P190

A

N19

1A

K19

2A

K19

3A wt

% B

AL

Cells

RSV

tite

rEo

sino

phili

a

Protection vs eosinophilia for Trx-G mutant vaccines

How can we improve the design of vaccines and/or therapeutics?

• Selective modification of viral epitopes to make safer, more effective vaccines

• Anti-cytokine or chemokine therapy- anti cyokine, chemokine antibodies- use vaccine adjuvants which favour selective

cytokine/chemokine profiles

Intranasal immunization:

• Directly targets respiratory tract• Induces mucosal immunity• Benign delivery

Mucosal vaccination strategy for RSV

RSV G

Immunization/challenge Protocol

Immunize mice 2x intranasally w Trx-G in liposomes

Inoculate RSV intranasally

Lungs• Virus Titers • Inflammatory cells• CytokinesBlood

4 days

14 days

Liposomal G128-229 vaccine protects mice against RSV R

SV ti

ter (

pfu/

g of

lung

)

PBS Liposomes G128-229 G128-229 inLiposomes

1

10

100

1000

10000

*

*

Summary

Summary

The respiratory tract in mucosal infection and vaccination

Seminar outline

- current state of vaccines for resp pathogens

- influenza

- RSV

- other respiratory pathogens

Bordetella pertussis filamentous hemagglutinin (FHA) as protective antigen against pertussis

FHA expressed in E. coli as fusion protein “Mal85”

Collaborators: Yan Huang, Song Lee, Scott Halperin

Liposomes for other vaccines?

highly contagious respiratory tract infection caused byBordetella pertussis

initially resembles an ordinary cold, whooping cough mayeventually turn more serious, particularly in infants

both cellular and acellular vaccines available, but haveunwanted side-effects or are expensive

Pertussis (whooping cough)

IgA (saliva)

IgG (serum)

Anti-Mal85 Immune responses in immunized mice

Protection with Mal85 against live challenge in immunized mice

Conclusions

• cytokines and chemokines modulate many aspects of viral disease

examples:IL-4, -5, -10 and -13 in RSV

• fine tuning of immune reponses possible through:- selective epitope mutagenesis/deletion- use of specific adjuvants

• liposomes and recombinant antigen are of potential vaccine value for respiratory pathogens, eg RSV andpertussis

Anderson Lab, CCfV, Dalhousie University

AcknowledgmentsDalhousie University Thammasat UniversityYan Huang Pramuan TapchaisriJean Marshall Santi ManeewatchararangsriSong Lee Ayham Al-Afif Khon Kaen UniversityRaidan Alyazidi Surasakdi Wongratanacheewin

Apichaya PuangpetchSupavadee Polyiam