View
224
Download
2
Category
Preview:
Citation preview
Manuscript Number HYPE201404534R3
Online Supplement for
Long-Term Reduction of High Blood Pressure
by Angiotensin II DNA Vaccine in Spontaneously Hypertensive Rats
Hiroshi Koriyama M.D., Ph.D a, Hironori Nakagami M.D., Ph.D a,1, Futoshi Nakagami,
M.D., Ph.D b,c, Mariana Kiomy Osako, Ph.D a, Mariko Kyutoku, Ph.D b, Munehisa
Shimamura M.D., Ph.D a, Hitomi Kurinami M.D., Ph.D a, Tomohiro Katsuya M.D.,
Ph.D b, Hiromi Rakugi M.D., Ph.D c, and Ryuichi Morishita M.D., Ph.D c,1
aDivision of Vascular Medicine and Epigenetics, Osaka University United Graduate
School of Child Development. 2-1 Yamada-oka, Suita, Osaka, 565-0871, Japan
bDepartment of Clinical Gene Therapy, Osaka University Graduate School of Medicine.
2-2 Yamada-oka, Suita, Osaka, 565-0871, Japan
cDepartment of Geriatric Medicine and Nephrology, Osaka University Graduate School
of Medicine. 2-2 Yamada-oka, Suita, Osaka, 565-0871, Japan
1Address correspondence to:
Ryuichi Morishita, M.D., Ph.D. Professor, Division of Clinical Gene Therapy, Osaka
University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka, 565-0871,
Japan. Tel: +81-6-6879-3406, Fax: +81-6-6879-3409, E-mail:
morishita@cgt.med.osaka-u.ac.jp
and
Hironori Nakagami, M.D., Ph.D. Professor, Division of Vascular Medicine and
Epigenetics, Osaka University United Graduate School of Child Development, 2-1
Yamada-oka, Suita, Osaka, 565-0871, Japan. Tel: +81-6-6879-4142, Fax: +81-6-6879-
4142 E-mail: nakagami@gts.med.osaka-u.ac.jp
Methods
Reagents
Anti-Ang II antibody, anti-Ang I antibody, anti-Ang1-7 antibody, anti-Ang-N antibody,
and anti-BSA antibody were purchased from Abcam. Anti- actin antibody was
purchased from Sigma-Aldrich. Olmesartan was purchased from Daiichi-Sankyo (Tokyo,
Japan.).
Vaccine synthesis
The HBc gene was obtained by PCR from the plasmid pPLc3 (BCCMTM/LMBP,
Plasmid Collection, University of Ghent, Belgium). To construct pcDNA3.1-HBc, the
HBc sequence was amplified by PCR using HBcF (5’-
gccatggatatcgatccttataaagaattcggagc-3’) and HBcR (5’-
ggcctctcactaacattgagattcccgagattgaga-3’) as forward and reverse primers, respectively.
The amplified fragment was inserted into the pcDNA3.1/V5-His-TOPO vector
(Invitrogen) by TA cloning according to the manufacturer’s protocol.
To construct pcDNA3.1-HBc-AngII, PCR was performed three times. First, the 5’ half
of the HBc ORF was amplified by PCR using HBcF and H2 (5’-
ggggtggatgtatacgcggtcagtgatagctggatcttccaagttaac-3’) primers. Second, the 3’ half of the
HBc ORF was amplified by PCR using H3 (5’-
ccgcgtatacatccacccctttggtgctactagcagggacctggtagtc-3’) and HBcR primers. Primer H2
contains the sequence of the spacer Ile-Thr dipeptide and the N-terminal half of Ang II.
Primer H3 contains the sequence of the C-terminal half of Ang II and the tripeptide spacer
Gly-Ala-Thr. Using these two amplified fragments as templates, a third PCR was
performed using primers HBcF and HBcR. The final amplified fragment contained the
Ang II sequence within the immunodominant region (aa 80-81) of HBc; this fragment
was inserted into the pcDNA3.1/V5-His-TOPO vector by TA cloning.
ISS containing four CpG motifs (CpG-A D19, 5’-ggtgcatcgatgcagggggg-3’; CpG-B
1018, 5’-tgactgtgaacgttcgagatga-3’; CpG-C C274, 5’-tcgtcgaacgttcgagatgat-3’ and CpG-
C C695 5’-tcgaacgttcgaacgttcgaacgtt-3’) was synthesized by PCR using the following
primers: CpGF (5’-tttcacgtagtgggtgcatcgatgcagg-3’), CpGR (5’-
ggtcactacgtgaacgttcgaacgttcg-3’) and templates: CpG1 (5’-
ggtgcatcgatgcaggggggtgactgtgaacgttcgagatgatcgtcgaacgttcgagatgattcgaacgttcgaacgttcga
acgtt-3’) and CpG2 (5’-
aacgttcgaacgttcgaacgttcgaatcatctcgaacgttcgacgatcatctcgaacgttcacagtcacccccctgcatcgatgc
acc-3’). The ISS fragment (112 bp) was digested with the restriction endonuclease DraIII
and inserted into the backbone of the pcDNA3.1-HBc-AngII-ISS(-) and pcDNA3.1-HBc-
ISS(-) plasmids.
Each of these constructed vectors was used to transform E. coli TOP10 competent cells
(Invitrogen), and resultant colonies were screened for ampicillin resistance and sequenced
to confirm correct insertions.
Animals and DNA immunization
The experiments were approved by the Ethical Committee for Animal Experiments of
the Osaka University Graduate School of Medicine. Eight-week-old male spontaneously
hypertensive rats (SHRs) were purchased from The Oriental Yeast (Osaka, Japan) and
were housed in a temperature- and light cycle-controlled animal facility with free access
to food and water. These experimental protocols were approved by the Ethical Committee
for animal experiments of the Osaka University Graduate School of Medicine. Rats were
randomly assigned into three groups; each group of rats was anesthetized, and received
DNA immunizations by a needleless injector, the Shima Jet (Shimazu, Japan). The HBc-
Ang II group was vaccinated three times with pcDNA3.1-HBc-AngII, while the HBc
group received pcDNA3.1-HBc and the saline group received saline only, all at 2-week
intervals. Each shot delivered 100 g of DNA, and two shots were delivered to each rat
on shaved back skin at each immunization. Blood samples before immunization and 2, 4,
8, 12, 16, 20 and 24 weeks after the first immunization were collected. Sera were isolated
and stored at -70 °C until use.
Measurement of BP and Ang II concentration
Arterial BP was measured at 4, 8, 12, 16, 20 and 24 weeks by the tail-cuff method (BP-
98A, SOFTRON, Japan). During measurements, the animals were held in a restraining
device. The SBP values are shown as the average of 10 readings for each animal at each
time. Plasma immunoreactive Ang II concentrations , Ang I concentrations, plasma renin
activity, and daily urinary excretion of aldosterone were measured by radioimmunoassay
by an external organization (FALCO Biosystems, Kyoto, Japan). Briefly, plasma Ang II
is measured by competitive ELISA. The protocol is as follows, 1) the ELISA plate is
coated by anti-angiotensin II antibody, 2) add sample plasma(s) to the ELISA plate with
defined radiolabelled angiotensin II, 3) plasma angiotensin II concentration is quantified
by measuring radioactivity bound to plate.
Enzyme-linked immunosorbent assay (ELISA)
Ang II-specific antibody responses were measured by coating ELISA plates with BSA-
Ang II conjugate. Ang II was conjugated with BSA at its N-terminus by suberic acid bis
(PEPTIDE INSTITUTE Inc., Osaka, Japan). BSA-Ang II conjugate was coated onto
ELISA plates at 10 g/ml in carbonate buffer overnight at 4 °C. After blocking with 5 %
skim milk solution in phosphate-buffered saline (PBS)/Tween, serum samples from
immunized animals were diluted 1:100 in PBS containing 5 % skim milk and then
incubated for 2 hours on the plate. Detection was performed by goat anti-rat IgG
horseradish peroxidase conjugate (NA935, GE Healthcare, Tokyo, Japan). The specificity
of the signal was confirmed by assaying preimmune serum, which gave the signal
background. The absorbance was read by a microplate reader (Bio-Rad Inc., Japan). Anti-
Ang I and anti-Ang1-7 antibody responses were measured by coating ELISA plates with
BSA-Ang I conjugate and BSA-Ang1-7 conjugate (PEPTIDE INSTITUTE Inc., Osaka,
Japan), respectively. IFN-, IL-2, IL-4, and IL-10 were measured by Quantikine ELISA
kit (R&D systems).
ELISPOT Assay
IFN-- and IL-2-producing T cells were quantified in splenocytes by ex vivo ELISPOT
assay after peptide stimulation for 24 hours. Briefly, sterile 96-well ELISPOT plates
(Millipore, Tokyo, Japan) were coated at 4 °C overnight with 50 l mouse IFN- or IL-2
mAb as recommended by the manufacturer (R&D Systems, Tokyo, Japan). After
overnight incubation, wells were blocked with 1.5 % BSA and 5 % sucrose. Freshly
isolated splenocytes from individual immunized rats were seeded in wells (106 cells/well)
and restimulated by 50 g/ml Phytohemaggulutinin (PHA), 3 g/ml recombinant HBc,
10 g/ml Ang II or 10 g/ml Ang-N in RPMI1640 medium. Splenocytes from saline-
injected rats and cells in culture medium alone were used as negative controls to
determine background levels. Each cell population was titrated in triplicate. A positive
response was defined as a median number of spot-forming cells (SFCs) in triplicate wells
at least twice that observed in control wells containing medium and at least 50 SFCs per
million splenocytes.
Western Blot Analysis.
BSA and the BSA-AngII conjugate were separated electrophoretically by SDS/PAGE
and blotted onto poly(vinylidene difluoride) membranes (Millipore). The blots were
incubated with sera from rats immunized with the HBc-AngII vaccine, preimmune, anti-
BSA antibody, or commercially available anti-Ang II antibody. For evaluation of the
expression of plasmid DNA in the transfected Hela cell, the cell lysate was collected in
RIPA lysis buffer (Millipore) and then subjected to SDS/PAGE. After electrophoresis,
the membrane was incubated with anti-Ang II antibody, anti-HBc antibody, or anti-
actin antibody, respectively. After incubation with HRP-conjugated antibodies specific
for rat IgG (GE Healthcare), chemiluminescence signal was detected with a FujiFilm LAS
1000 camera and analyzed with MultiGauge version 3.2 software.
Statistics
All values are expressed as the mean ± standard errors. Data were compared using two-
way analysis of variance (ANOVA) followed by Dunnett’s test for pair-wise comparisons
against the control groups and Tukey’s test for multiple comparisons. P values less than
0.05 were considered statistically significant. All statistical analyses were performed
using JMP8 software (SAS Institute, Inc., Cary, NC, USA).
pcDNA3.1-HBc
6176 bp
ISS
SV40 ori
pcDNA3.1-HBc-AngII
6215 bp
SV40 ori
-I-T- -G-A-T-
Angiotensin II
DRVYIHPF
HBc-N HBc-C
pUC
Amp
HBc-N
ISS
pUC
Neo
Amp
Pcmv PcmvHBc
AngII
Fig. S-1. Construction of DNA vaccines. A, Plasmid map of pcDNA3.1 -HBc.
HBc gene was cloned downstream of CMV promoter. ISS sequence containing
CpG-A D19, CpG-B 1018, CpG-C C274 and CpG-C C695 was also inserted. B,
Plasmid map of pcDNA3.1-HBc-AngII. DNA fragment encoding angiotensin II
and its N- and C-terminal linkers were inserted at the position corresponding to
amino acid 80-81 of HBc. C, Schematic presentation of fusion protein HBc-
angiotensin II expressed by plasmid pcDNA3.1-HBc-AngII. Angiotensin II was
inserted in HBc protein at aa 80-81 and the N-terminal I-T dipeptide linker and
a C-terminal G-A-T tripeptide were designed in frame to angiotensin II to allow
flexibility in the conformation of angiotensin II when surface-exposed on HBc
particle. The angiotensin II and the linkers were represented by single-letter
codes.
HBc-C
Neo
A B
C
Fig. S-2. Expression of plasmid DNA. Hela cells were transfected with
plasmids, and expression of HBc-AngII protein (Allowhead) was only
detected in the cell lysate transfected with pcDNA3.1-HBc-AngII by
immunoblot using anti-Angiotensin II antibodies. Expression of HBc-AngII
protein and HBc protein was detected in the immunoblot with anti-HBc
antibody. Lane 1, the untreated cell lysate; lane 2, the cell lysate transfected
with pcDNA3.1-HBc-AngII; and lane 3, the cell lysate transfected with
pcDNA3.1-HBc. *, HBc makes dimers.
Anti-HBc Anti-AngII
1 2 3 1 2 3
*
Anti-b-actin 42 kDa
1 2 3
Fig. S-3. Plasma renin activity, Plasma Ang I concentration, and Daily urinary
excretion of aldosterone. A, Plasma renin activity of vaccinated rats. Plasma
samples were collected from rats 8 weeks after the first immunization. Saline
group, n=5; HBc-AngII group, n=6. B, Plasma Ang I concentration of vaccinated
rats. Plasma samples were collected from rats 8 weeks after the first immunization.
Saline group, n=2; HBc-AngII group, n=3. C, Daily urinary excretion of
aldosterone. Urine samples were collected from rats 24 weeks after the first
immunization. HBc and Saline group, n=6; HBc-AngII group, n=5. Data are
presented as the average of each group; error bars indicate the standard error of the
mean. *P<0.01 vs. HBc-AngII group.
0
Da
ily u
rin
ary
excre
tio
n o
f
ald
oste
ron
e (
ng/d
ay)
2
6
8
10
HBc, saline HBc-AngII
*
4
12
14
C
0
Imm
un
ore
active
pla
sm
a
An
g I c
on
ce
ntr
ation (
pg/m
l)
100
200
300
Saline HBc-AngII
400
B
500
600P = 0.09
0
Pla
sm
a r
en
in a
ctivity (
ng/m
l/h
r)
2
6
8
10
Saline HBc-AngII
4
12
14
A
16
18
Fig. S-4. The effect of vaccination on systolic BP in WKY rats. Eight-
week-old male WKY rats (n=5) were vaccinated three times with
pcDNA3.1-HBc-AngII at 2-week intervals. Systolic BP was measured at 0
and 6 weeks after the first immunization. Data are presented as the average
of each group; error bars indicate the standard error of the mean.
0
Systo
ric b
loo
d p
ressu
re (
mm
Hg)
20
60
80
100
0 week 6 weeks
40
120
140
160
Fig. S-5. The effect of A779 or ARB treatment in the HBc-AngII group.
SHRs were vaccinated three times with pcDNA3.1-HBc-AngII at 2-week
intervals (0, 2nd, 4th week). The administration of A779 (0.8 mg/kg/day,
I.P., for 7days) or olmesartan (3 mg/kg/day, P.O., for 7 days) was started at
5th week. Systolic BP was measured at 6th week. Data are presented as the
average of each group; error bars indicate the standard error of the mean.
*P<0.05 vs. saline group. n=4 per group.
150
Systo
lic b
loo
d p
ressu
re (
mm
Hg)
160
180
190
200
Saline HBc-AngII
170
210
220
230
OlmesartanHBc-AngII
+
Olmesartan
HBc-AngII
+
A779
* * **
Saline
Kidney
Heart
A
B
HBc-AngIIHBc
Fig. S-6. Histological conditions of kidney and heart. A, Photomicrographs
of sections of kidney from SHR of the saline group, the pcDNA3.1-HBc-AngII
vaccinated group and the pcDNA3.1-HBc group. Scale bar, 100mm. B,
Photomicrographs of sections of heart from SHR of the saline group, the
pcDNA3.1-HBc-AngII vaccinated group and the pcDNA3.1-HBc group. Scale
bar, 100mm
Saline HBc-AngIIHBcLiver
Aorta
A
B
Fig. S-7. Histological conditions of liver and aorta. A, Photomicrographs of
sections of liver from SHR of the saline group, the pcDNA3.1-HBc vaccinated
group and the pcDNA3.1-HBc-AngII group. Scale bar, 100mm. B,
Photomicrographs of sections of aorta from SHR of the saline group, the
pcDNA3.1-HBc vaccinated group and the pcDNA3.1-HBc-AngII group. Scale
bar, 100mm.
Fig. S-8. Conceptual map of this experiment. Our working hypothesis of
AngII vaccine therapy was shown as a conceptual figure. We immunized mice
with HBc-AngII as an antigen. As an immunization phase, antigen presenting
cells (APCs) phagocyte HBc-AngII and present T cell epitope of HBc-AngII to
T cells through major histocompatibility complex (MHC), and T cells recognize
it through T cell epitope and activate (differentiate to effector T cells) (step 1). B
cells, which are specific to AngII, phagocyte HBc-AngII and present T cell
epitope of HBc-AngII to T cells through MHC. Then, B cells differentiate to
plasmacytes and produce antibodies with help of activated T cells (effector T
cells) (step 2). These steps are required to produce antibodies efficiently.
Recommended