Controlled Human Malaria Infection: Strength of a … Human Malaria Infection: Strength of a human...
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Controlled Human Malaria Infection (CHMI)
Infective
mosquito bite
Microscopy positive
treatment
Liver stage Blood stage
End of
study
R. Sauerwein et al. Nat Rev Immunol 2011
Parasitaemia after CHMI
RTQ-PCR N=48
Microscopy N=48
• Parasitemia in 100% of the volunteers
• Microscopy: Thick smear positive day 7-12
• RTQ-PCR: Cyclic growth of parasites
Treatment
Treatment
Parasitaemia after CHMI
RTQ-PCR N=48
Microscopy N=48
• Parasitemia in 100% of the volunteers
• Microscopy: Thick smear positive day 7-12 (sensitivity
4000 par/ml)
• RTQ-PCR: Cyclic growth of parasites (sensitivity 20 par/ml)
Treatment
Treatment
Hermsen C et al. MBP: 2001
Parasitaemia by qPCR after bites of 5 infected mosquitoes
in 7 CHMI trials in a total of 64 volunteers.
post- infection
Sauerwein R et al, unpublished
+ microscopy
for parasites
Controlled Human Malaria infection (CHMI)
bites of 5 Pf NF54 infected mosquitoes
2 4 6 8 10 12 14 16 18 20 22 24
qPCR (20 Pf/ml)
blood-stage
Thick smear (4000Pf/ml))
Liver-stage
Treatment at thick-smear positive
Data from 48 volunteers in 7 CHMI trials
Roestenberg et al., JID, 2012
Sauerwein R et al, Nat Rev Immunol 2011
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# P
f /
ml
Days after infection
Statistical model Fitting the data into THE MODEL
Hermsen C et al AMJTMH 2004
# Hepatocytes infected: 207 (29-560)
Asexual cycle 43.7 hrs (42.2-45.6)
rings 28.3 hrs
mature trophs 15.4 hrs
Multiplication factor : 7.50 (6.1-9.6)
Pre-patent period :
MPS 8.8 days (7.3-10.3)
PCR 6.8 days (6.7-7.3)
Estimated parasitological parameter values
Hermsen C et al AMJTMH 2004:71:196
(a) Pre-erythrocytic vaccine
1
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1000000
4 6 8 10 12
Days after infection
1 +
# P
f /
ml
(b) A-sexual stage vaccine
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10000
100000
1000000
4 6 8 10 12
Days after infection
1 +
# P
f /
ml
0 %
60%
95%
99%
0 %
30%
60%
90%
Simulated kinetics of parasitemia for different vaccine efficacies
Hermsen C et al AMJTMH 2004:71:196
Bloodstage vaccine
Liver-stage vaccine
Harmonization of Design and Conduct of CHMI
by Mosquito bite
CHMI Mosquito Centers in the world:
1. USMMVP, US
2. Sanaria/ NIH/ University of Maryland, US
3. Seattle Biomedical Research Institute , US
4. Oxford University, UK
5. Radboud University Medical Centre,NL
Input from USAID, US FDA, NIAID, PATH MVI, EC and EVI. Input from WHO committees
Meetings: Bethesda, MD, USA in March 2009; Arusha, Tanzania March 2010 ; Washington, DC in June
2010 (WHO); Amsterdam, June 2011 (EMVDA)
PfSPZ challenge
• Advantage: • Easy access for global application in appropriate clinical settings. • RadboudUMC, NL, Oxford University, UK, Tuebingen University, Germ. CRESIB, Spain, NIH, US. U. Maryland, US, IHC,
Tanzania, KEMRI, Kenya ,MRTC, Mali, etc
•
: However:
30-100 fold less potent compared to Pf-infected mosquitoes bites: • Viability/potency • Administration (route, device, volume)
13
In vivo imaging of Pb GFP-Luccon parasites
Intravenous versus intradermal injection of sporozoites
i.v injection
i.d injection
44 hrs post
infection
Ploemen I. et al: Vaccine 2103
Administration of aseptic cryopreserved sporozoites
(Sanaria)
Direct intravenous inoculation
Bypass the skin
3200 Spz (30-60 mosquitoes)
•5-10x more potent than ID or IM
•Bypass of immune interference
against spz in the skin
Administration of Pf-infected red blood cells intravenously
Centres:
•QIMR, Austr.
•Oxford University, UK
•RadboudUMC, NL
Cheng AMJTMH 1997; Pombo Lancet 2002
Sanderson AMJTMH 2008, Bijker PNAS 2013
Parasite growth after blood stage infection
PCR determined parasite growth curves
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100,000
1,000,000
10,000,000
3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9
Days after inoculation
Pa
ras
ite
s/m
l Subject 1
Subject 2
Subject 3
Subject 4
Subject 5
Sanderson et al. AJTMH 2008; 878
Blood stage challenge
• Advantage: • Measurement of 4-5 asexual multiplication cycles (compared to 2-3
cycles after mosquito challenge) • However:
• Inoculum (1800 iRBC) is unphysiologically low:
10-20x lower than iRBC from 1 infective spz • Is missing sporo/pre-erythrocytic and cross stages antigens
• blood stage and sporo/liver stages: LSA3, AMA1, MSP1……
• Potential induction of immune responses by very low
parasitemia trivial?
18
20
Protection: • RTS/S: P. falciparum CSP fused to HBsAg/AS01E 30-50% NEJM 2011 365:1863; NEJM 2012 367 2283; NEJM 2013 368:1111 Thera et al NEJM 2011;365:1004 www.who.int/vaccine_research/links/Rainbow/en/index.html
RTS/S Sub-unit vaccine
Interim Results Efficacy Phase IIb/III trial
Efficacy CHMI parallels Phase IIb/III outcome
Limited success of these subunit vaccines
• Poor immunogenicity of individual antigens, Adjuvants; Viral platforms; Prime boost strategies
• Antigenic diversity of the selected target proteins Genetic diversity coverage • Insufficient breadth and coverage of the induced
immune response based on mostly single antigens. Antigen Mix/ Match or Attenuated whole parasite
Roestenberg & McCall et al., NEJM, 2009
Roestenberg et al., Lancet, 2011
Chloroquine Prophylaxis and Sporozoites (CPS) Immunization
Parasitemia post Challenge
qPCR
Chloroquine prophylaxis (3 months)
CPS Immunization
3 x 12-15 PfSpz infected mosquito-bites 5 PfSpz infected mosquito-bites
Protection after CPS-immunization
CPS-immunization induces 100% homologous protection.
Roestenberg & McCall et al., NEJM, 2009
CPS-induced protection is immunization dose-dependent
Roestenberg & McCall et al., NEJM, 2009
Bijker & Bastiaens et al., PNAS, 2013
Bijker & Teirlinck et al., JID 2014
5/10
3/5
8/9
19/20
1. Which immune responses are induced by CPS-immunization?
2. Can any of these immune responses correlate with sterile
protection from re-infection?
Dissect CPS-induced immune signature
CPS Immune Reactive
84 Antigens
Reactive in Both
90 Antigens
Semi-Immune Reactive
238 Antigens
CSP
LSA1
MSP2
MSP10
MSP1
MSP (H101)
MSP11
LSA3
Antigen targets of CPS-induced antibodies Comparing CPS Antibody profile with semi-immune Kenyan sera
Felgner Ph et al Sci Rep 2013
Pre-erythrocytic
antigens
Cross-stage
antigens
Blood stage
antigens
Immune Correlate of Protection
Chemo-Prophylaxis and Sporozoites (CPS)
Analysis of cellular immune responses
Antibodies
CD4 T cells: IFNγ +/- IL-2
CD8 T cells: IFNγ Cytotoxicity CD107a: degranulation marker Granulysin / Granzyme B: cytotoxic molecules
The RUMC Clinical Malaria Program after >300 CHMI
Controlled human Malaria Infections (CHMI):
• Major upgrade by introduction of molecular detection of parasites by qPCR and development of statistical model
Chemo-Prophylaxis and Sporozoite (CPS) immunization :
• Simple and novel immunization regime inducing long lasting sterile protection with 95% efficacy
• “Better than Nature “ immunzation protocol challenges dogma’s on
naturally acquired malaria immunitity
• Biomarker for protection: First steps in delineation of protective immune signatures
• Identification of (new) target antigens for protection by system immunological approach
bbb
Clinical team
Else Bijker
Guido Bastiaens
Matthew McCall
Meta Roestenberg
Jorien Wiersma
Linda Wammes
Remko Schats
Quirijn de Mast
Andre van der Ven
Leo Visser
Perry van Genderen
Immunology team Anne Teirlinck
Wiebke Nahrendorf Marije Behet Anja Scholzen
Parasite team
Marga vd Vegte-Bolmer Rianne Siebelink-Stoter
Wouter Graumans
Mosquito team Geert-Jan van Gemert
Laura Pelser-Posthumus Astrid Pouwelsen
Jacqueline Kuhnen Jolanda Klaassen
GAP team
Ben van Schaijk Martijn Vos
Ivo Ploemen Takechi Annoura Shahid Khan Chris Janse
Diagnostic team
Rob Hermsen
Theo Arens
Karina Teelen
Lisette van Lieshout
Jaco Verweij
Jaap van Hellemond
CCMS-the Netherlands:
RUMC /LUMC/EMC
Malaria Vaccine Team
Collaborators
•Sanaria
SL Hoffman
STPH Basel/ Bagamoyo
S. Shekalaghi
C Daubenberger
INSERM
Dominique Mazier
J-F. Franetich
•UC Irvine:
Ph. Felgner
•CEVAC – Ghent
L Foquet
G Leroux-Rouls