Multipeptide and passive immunization for atherosclerosis

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Multipeptide and passive immunization for
atherosclerosis

• Jan Nilsson
• Department of Medicine, Malmö University
  Hospital, Lund University

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Is it possible to produce a vaccine against
atherosclerosis?

• What structures in oxidized LDL are recognized by
  the immune system?
• Are these immune responses associated with
  cardiovascular disease humans?
• Can protective immune responses be selectively
  activated by a vaccine?
• Can antibodies be used directly to treat
  atherosclerosis?

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CD4 T cells recognize oligopeptide epitopes
G Cooper, The Cell
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(No Transcript)
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Binding of antibodies in human plasma to native
and MDA-modified peptide sequences in apo B-100
129
1
302
Peptide
45
74
102
129
32
210
245
162
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Active immunization of apo E null mice with apo
B-100 peptide sequences

• Immunization with 100 mg peptides at 6, 9 and 11
  weeks of age using Alum as adjuvant
• High cholesterol diet at 10 weeks of age
• Atherosclerosis assessed by Oil Red O staining of
  the descending aorta at 25 weeks of age

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Effect of oxidized LDL peptide vaccines on
atherosclerosis in mice
atherosclerosis
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Effect of immunization with MDA-apo B 100 peptide
45 on specific IgM, IgG, IgG1 (Th2) and IgG2a
(Th1) in apo E0 mice
plt0.05, plt0.005
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Immunization using MDA-apo B-100 peptides in mice

• Reduction of atherosclerosis by up to 70
• Remaining plaques contain more collagen and less
  macrophages
• Increase in IgG but not IgM
• Switch from Th1 to Th2-specific IgG
• No significant effects on plasma lipids

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Passive immunization strategy

• Human IgG1 against peptides 45 and 210 were
  produced through screening of a single chain
  antibody fragment library and subsequent cloning
  into a pcDNA3 vector
• Apo E knockout mice were given high cholesterol
  diet from 6 weeks
• Immunization with 0.5 mg antibody at 20, 21 and
  22 weeks
• Sacrificed at 25 weeks
• Effects assessed by ORO staining of descending
  aorta, Trichrome Masson staining and macrophage
  immunostaining of subvalvular plaques.

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Effect of passive immunization with recombinant
human IgG against peptide 45 on early
atherosclerosis in mice
Schiopu et al, Circulation 2004
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Effect of passive immunization on macrophages in
atherosclerotic plaques
FITC IgG (control)
plt0.05
Peptide 45 IgG (IEI-E3)
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Effect of passive immunization with recombinant
human IgG against apo B peptides on advanced
atherosclerosis in mice
Plt0.005
Plt0.01
Plt0.001
atherosclerosis
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Conclusions

• Several possible targets for atherosclerosis
  vaccines identified
• Pilot vaccine studies in mice
• Recombinant human IgG used for passive
  immunization in mice

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IgM against MDA-modified peptide sequence 32 in
apoB-100 and oxidized LDL in CHD cases
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IgM against MDA-modified amino acids sequence
between 3136 and 3155 in apo B-100 (peptide 210)
and progression of carotid IMT during 3 years
Nordin Fredrikson et al, submitted
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Association between autoantibodies to MDA-apo B
100 epitopes and carotid plaque structure (n114)
plt0.05, plt0.01,plt0.001
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Antibodies to oxidized LDL antigens (MDA-apo B
100) in humans

• Over 100 human oxidized LDL antibodies were found
  to bind to specific MDA-modified peptide
  sequences in apo B-100
• IgM appear more common than IgG
• IgM levels decrease with age
• High IgM levels are associated with increased
  severity and progression of atherosclerosis as
  assessed by carotid artery IMT
• High IgM levels are associated with lower levels
  of oxidized LDL in plasma
• IgM/IgG ratio may reflect plaque structure

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Department of Medicine, UMAS, Lund
University Gunilla Nordin Fredrikson Marie
Lindholm Mikko Ares Jan Åke Nilsson Ragnar
Alm Linda Petterson Bo Hedblad Ingrid
Söderberg Göran Berglund Stefan Jovinge Jan
Nilsson Maria Stollenwerk Lena Brånen Isabel
Goncalves Eva Bengtsson Anna Larsson Alexandru
Schiopu Jenny Persson Mihaela Nitulescu Fong
To Gertrud Jensen Irena Ljungcrantz Bioinvent
International, Lund Roland Carlsson Jenny
Bengtsson Bo Jansson Division of Cardiology,
Cedars-Sinai Medical Center, UCLA Bojan
Cercek Kuang-Yuh Chyu Prediman K Shah