ORCID Profile
0000-0002-4510-5602
Current Organisations
Georg-August-Universität Göttingen Fakultät für Physik
,
Walter and Eliza Hall Institute of Medical Research
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Publisher: Public Library of Science (PLoS)
Date: 04-12-2020
DOI: 10.1371/JOURNAL.PONE.0238010
Abstract: Multiplexed bead-based assays that use Luminex ® xMAP ® technology have become popular for measuring antibodies against proteins of interest in many fields, including malaria and more recently SARS-CoV-2/COVID-19. There are currently two formats that are widely used: non-magnetic beads or magnetic beads. Data are lacking regarding the comparability of results obtained using these two types of beads, and for assays run on different instruments. Whilst non-magnetic beads can only be run on flow-based instruments (such as the Luminex ® 100/200™ or Bio-Plex ® 200), magnetic beads can be run on both these and the newer MAGPIX ® instruments. In this study we utilized a panel of purified recombinant Plasmodium vivax proteins and s les from malaria-endemic areas to measure P . vivax -specific IgG responses using different combinations of beads and instruments. We directly compared: i) non-magnetic versus magnetic beads run on a Bio-Plex ® 200, ii) magnetic beads run on the Bio-Plex ® 200 versus MAGPIX ® and iii) non-magnetic beads run on a Bio-Plex ® 200 versus magnetic beads run on the MAGPIX ® . We also performed an external comparison of our optimized assay. We observed that IgG antibody responses, measured against our panel of P . vivax proteins, were moderately-strongly correlated in all three of our comparisons (pearson r .5 for 18/19 proteins), however higher amounts of protein were required for coupling to magnetic beads. Our external comparison indicated that results generated in different laboratories using the same coupled beads are also highly comparable (pearson r .7), particularly if a reference standard curve is used.
Publisher: The American Association of Immunologists
Date: 03-2017
Abstract: Since the demonstration of sterile protection afforded by injection of irradiated sporozoites, CD8+ T cells have been shown to play a significant role in protection from liver-stage malaria. This is, however, dependent on the presence of an extremely high number of circulating effector cells, thought to be necessary to scan, locate, and kill infected hepatocytes in the short time that parasites are present in the liver. We used an adoptive transfer model to elucidate the kinetics of the effector CD8+ T cell response in the liver following Plasmodium berghei sporozoite challenge. Although effector CD8+ T cells require & h to find, locate, and kill infected hepatocytes, active migration of Ag-specific CD8+ T cells into the liver was not observed during the 2-d liver stage of infection, as ided cells were only detected from day 3 postchallenge. However, the percentage of donor cells recruited into ision was shown to indicate the level of Ag presentation from infected hepatocytes. By titrating the number of transferred Ag-specific effector CD8+ T cells and sporozoites, we demonstrate that achieving protection toward liver-stage malaria is reliant on CD8+ T cells being able to locate infected hepatocytes, resulting in a protection threshold dependent on a fine balance between the number of infected hepatocytes and CD8+ T cells present in the liver. With such a fine balance determining protection, achieving a high number of CD8+ T cells will be critical to the success of a cell-mediated vaccine against liver-stage malaria.
Publisher: American Astronomical Society
Date: 30-06-2022
Abstract: We explore the transit timing variations (TTVs) of the young (22 Myr) nearby AU Mic planetary system. For AU Mic b, we introduce three Spitzer (4.5 μ m) transits, five TESS transits, 11 LCO transits, one PEST transit, one Brierfield transit, and two transit timing measurements from Rossiter–McLaughlin observations for AU Mic c, we introduce three TESS transits. We present two independent TTV analyses. First, we use EXOFASTv2 to jointly model the Spitzer and ground-based transits and obtain the midpoint transit times. We then construct an O − C diagram and model the TTVs with Exo-Striker . Second, we reproduce our results with an independent photodynamical analysis. We recover a TTV mass for AU Mic c of 10.8 − 2.2 + 2.3 M ⊕ . We compare the TTV-derived constraints to a recent radial velocity (RV) mass determination. We also observe excess TTVs that do not appear to be consistent with the dynamical interactions of b and c alone or due to spots or flares. Thus, we present a hypothetical nontransiting “middle-d” candidate exoplanet that is consistent with the observed TTVs and candidate RV signal and would establish the AU Mic system as a compact resonant multiplanet chain in a 4:6:9 period commensurability. These results demonstrate that the AU Mic planetary system is dynamically interacting, producing detectable TTVs, and the implied orbital dynamics may inform the formation mechanisms for this young system. We recommend future RV and TTV observations of AU Mic b and c to further constrain the masses and confirm the existence of possible additional planet(s).
Publisher: American Society of Tropical Medicine and Hygiene
Date: 02-11-2016
Publisher: Public Library of Science (PLoS)
Date: 16-02-2021
DOI: 10.1371/JOURNAL.PNTD.0009165
Abstract: Antibody responses as serological markers of Plasmodium vivax infection have been shown to correlate with exposure, but little is known about the other factors that affect antibody responses in naturally infected people from endemic settings. To address this question, we studied IgG responses to novel serological exposure markers (SEMs) of P . vivax in three settings with different transmission intensity. We validated a panel of 34 SEMs in a Peruvian cohort with up to three years’ longitudinal follow-up using a multiplex platform and compared results to data from cohorts in Thailand and Brazil. Linear regression models were used to characterize the association between antibody responses and age, the number of detected blood-stage infections during follow-up, and time since previous infection. Receiver Operating Characteristic (ROC) analysis was used to test the performance of SEMs to identify P . vivax infections in the previous 9 months. Antibody titers were associated with age, the number of blood-stage infections, and time since previous P . vivax infection in all three study sites. The association between antibody titers and time since previous P . vivax infection was stronger in the low transmission settings of Thailand and Brazil compared to the higher transmission setting in Peru. Of the SEMs tested, antibody responses to RBP2b had the highest performance for classifying recent exposure in all sites, with area under the ROC curve (AUC) = 0.83 in Thailand, AUC = 0.79 in Brazil, and AUC = 0.68 in Peru. In low transmission settings, P . vivax SEMs can accurately identify in iduals with recent blood-stage infections. In higher transmission settings, the accuracy of this approach diminishes substantially. We recommend using P . vivax SEMs in low transmission settings pursuing malaria elimination, but they are likely to be less effective in high transmission settings focused on malaria control.
Publisher: MDPI AG
Date: 31-05-2023
DOI: 10.3390/PATHOGENS12060791
Abstract: The utilisation of serological surveillance methods for malaria has the potential to identify in iduals exposed to Plasmodium vivax, including asymptomatic carriers. However, the application of serosurveillance varies globally, including variations in methodology and transmission context. No systematic review exists describing the advantages and disadvantages of utilising serosurveillance in various settings. Collation and comparison of these results is a necessary first step to standardise and validate the use of serology for the surveillance of P. vivax in specific transmission contexts. A scoping review was performed of P. vivax serosurveillance applications globally. Ninety-four studies were found that met predefined inclusion and exclusion criteria. These studies were examined to determine the advantages and disadvantages of serosurveillance experienced in each study. If studies reported seroprevalence results, this information was also captured. Measurement of antibodies serves as a proxy by which in iduals exposed to P. vivax may be indirectly identified, including those with asymptomatic infections, which may be missed by other technologies. Other thematic advantages identified included the ease and simplicity of serological assays compared to both microscopy and molecular diagnostics. Seroprevalence rates varied widely from 0–93%. Methodologies must be validated across various transmission contexts to ensure the applicability and comparability of results. Other thematic disadvantages identified included challenges with species cross-reactivity and determining changes in transmission patterns in both the short- and long-term. Serosurveillance requires further refinement to be fully realised as an actionable tool. Some work has begun in this area, but more is required.
Publisher: Cold Spring Harbor Laboratory
Date: 07-08-2020
DOI: 10.1101/2020.08.07.20169862
Abstract: To achieve malaria elimination, new tools are required to explicitly target Plasmodium vivax . Recently, a novel panel of P. vivax proteins were identified and validated as serological markers for detecting recent exposure to P. vivax within the last 9 months. In order to improve the sensitivity and specificity of these markers, IgM in addition to IgG antibody responses were assessed to a down-selected panel of 20 P. vivax proteins. IgM was tested using archival plasma s les from observational cohort studies conducted in malaria-endemic regions of Thailand and Brazil. IgM responses to these proteins generally had poorer classification performance than IgG.
Publisher: Oxford University Press (OUP)
Date: 21-10-2014
Publisher: Cold Spring Harbor Laboratory
Date: 10-08-2020
DOI: 10.1101/2020.08.10.243980
Abstract: Multiplexed bead-based assays that use Luminex xMAP ® technology have become popular for measuring antibodies against proteins of interest in many fields, including malaria and more recently SARS-CoV-2/COVID-19. There are currently two formats that are widely used: non-magnetic beads or magnetic beads. Data is lacking regarding the comparability of results obtained using these two types of beads, and for assays run on different instruments. Whilst non-magnetic beads can only be run on flow-based instruments (such as the Luminex ® 100/200™ or Bio-Plex ® 200), magnetic beads can be run on both these and the newer MAGPIX ® instruments. In this study we utilized a panel of purified recombinant Plasmodium vivax proteins and s les from malaria-endemic areas to measure P. vivax -specific IgG responses using different combinations of beads and instruments. We directly compared: i) non-magnetic versus magnetic beads run on a Bio-Plex ® 200, ii) magnetic beads run on the Bio-Plex ® 200 versus MAGPIX ® and iii) non-magnetic beads run on a Bio-Plex ® 200 versus magnetic beads run on the MAGPIX ® . We also performed an external validation of our optimized assay. We observed that IgG antibody responses, measured against our panel of P. vivax proteins, were strongly correlated in all three of our comparisons, however higher amounts of protein were required for coupling to magnetic beads. Our external validation indicated that results generated in different laboratories using the same coupled beads are also highly comparable, particularly if a reference standard curve is used.
Publisher: Public Library of Science (PLoS)
Date: 30-03-2015
Publisher: American Society for Microbiology
Date: 22-01-2020
DOI: 10.1128/IAI.00573-19
Abstract: Despite promising progress in malaria vaccine development in recent years, an efficacious subunit vaccine against Plasmodium falciparum remains to be licensed and deployed. Cell-mediated protection from liver-stage malaria relies on a sufficient number of antigen-specific T cells reaching the liver during the time that parasites are present. A single vaccine expressing two antigens could potentially increase both the size and breadth of the antigen-specific response while halving vaccine production costs.
Publisher: Springer Science and Business Media LLC
Date: 03-05-2019
DOI: 10.1038/S41598-019-43120-X
Abstract: A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
Publisher: Public Library of Science (PLoS)
Date: 19-06-2014
Publisher: Springer Science and Business Media LLC
Date: 30-11-2011
DOI: 10.1007/S00335-010-9302-6
Abstract: Malaria is a disease that infects over 500 million people, causing at least 1 million deaths every year, with the majority occurring in developing countries. The current antimalarial arsenal is becoming dulled due to the rapid rate of resistance of the parasite. However, in populations living in malaria-endemic regions there are many ex les of genetic-based resistance to the severe effects of the parasite Plasmodium. Defining the genetic factors behind host resistance has been an area of great scientific interest over the last few decades this review summarizes the current knowledge of the genetic loci involved. Perhaps the lessons learned from the natural variation in both the human populations and experimental mouse models of infection may pave the way for novel resistance-proof antimalarials.
Publisher: Springer Science and Business Media LLC
Date: 04-03-2022
DOI: 10.1186/S12936-022-04085-X
Abstract: Plasmodium vivax is emerging as the dominant and prevalent species causing malaria in near-elimination settings outside of Africa. Hypnozoites, the dormant liver stage parasite of P. vivax , are undetectable to any currently available diagnostic test, yet are a major reservoir for transmission. Advances have been made to harness the naturally acquired immune response to identify recent exposure to P. vivax blood-stage parasites and, therefore, infer the presence of hypnozoites. This in-development diagnostic is currently able to detect infections within the last 9-months with 80% sensitivity and 80% specificity. Further work is required to optimize protein expression and protein constructs used for antibody detection. The antibody response against the top performing predictor of recent infection, P. vivax reticulocyte binding protein 2b (PvRBP2b), was tested against multiple fragments of different sizes and from different expression systems. The IgG induced against the recombinant PvRBP2b fragments in P. vivax infected in iduals was measured at the time of infection and in a year-long observational cohort both conducted in Thailand. The antibody responses to some but not all different sized fragments of PvRBP2b protein are highly correlated with each other, significantly higher 1-week post- P. vivax infection, and show potential for use as predictors of recent P. vivax infection. To achieve P. vivax elimination goals, novel diagnostics are required to aid in detection of hidden parasite reservoirs. PvRBP2b was previously shown to be the top candidate for single-antigen classification of recent P. vivax exposure and here, it is concluded that several alternative recombinant PvRBP2b fragments can achieve equal sensitivity and specificity at predicting recent P. vivax exposure.
Publisher: Elsevier BV
Date: 06-2022
Publisher: Frontiers Media SA
Date: 15-09-2015
Publisher: Public Library of Science (PLoS)
Date: 18-06-2013
Publisher: Cold Spring Harbor Laboratory
Date: 02-07-2020
DOI: 10.1101/2020.07.01.20143503
Abstract: Antibody responses as serological markers of Plasmodium vivax infection have been shown to correlate with exposure, but little is known about the other factors that affect antibody responses in naturally infected people from endemic settings. To address this question, we studied IgG responses to novel serological exposure markers (SEMs) of P. vivax in three settings with different transmission intensity. We validated a panel of 34 SEMs in a Peruvian cohort with up to three years’ longitudinal follow-up using a multiplex platform and compared results to data from cohorts in Thailand and Brazil. Linear regression models were used to characterize the association between antibody responses and age, the number of detected blood-stage infections during follow-up, and time since previous infection. Receiver Operating Characteristic (ROC) analysis was used to test the performance of SEMs to identify P. vivax infections in the previous 9 months. Antibody titers were associated with age, the number of blood-stage infections, and time since previous P. vivax infection in all three study sites. The association between antibody titers and time since previous P. vivax infection was stronger in the low transmission settings of Thailand and Brazil compared to the higher transmission setting in Peru. Of the SEMs tested, antibody responses to RBP2b had the highest performance for classifying recent exposure in all sites, with area under the ROC curve (AUC) = 0.83 in Thailand, AUC = 0.79 in Brazil, and AUC = 0.68 in Peru. In low transmission settings, P. vivax SEMs can accurately identify in iduals with recent blood-stage infections. In higher transmission settings, the accuracy of this approach diminishes substantially. We recommend using P. vivax SEMs in low transmission settings pursuing malaria elimination, but they are likely to be less effective in high transmission settings focused on malaria control. Plasmodium vivax still poses a threat in many countries due to its ability to cause recurrent infections. Key to achieving the goal of malaria elimination is the ability to quickly detect and treat carriers of relapsing parasites. Failing to identify this transmission reservoir will hinder progress towards malaria elimination. Recently, novel serological markers of recent exposure to P. vivax (SEM) have been developed and validated in low transmission settings. It is still poorly understood what factors affect the antibody response to these markers when evaluated in contrasting endemic contexts. To determine the factors that influence the antibody response to SEM, we compared the antibody levels in three sites with different transmission intensity: Thailand (low), Brazil (moderate) and Peru (high). In this study, we found that transmission intensity plays a key role in the acquisition of the antibody repertoire to P . vivax . In highly endemic sites, it is likely that immunological memory resulting from a constant and sustained exposure will impact the performance of SEMs to detect in iduals with recent exposure to P . vivax . In summary, SEMs that perform well in low transmission sites do not perform as well in high transmission regions.
Publisher: American Society for Microbiology
Date: 03-2017
DOI: 10.1128/IAI.00641-16
Abstract: Efforts are under way to improve the efficacy of subunit malaria vaccines through assessments of new adjuvants, vaccination platforms, and antigens. In this study, we further assessed the Plasmodium falciparum antigen upregulated in infective sporozoites 3 (PfUIS3) as a vaccine candidate. PfUIS3 was expressed in the viral vectors chimpanzee adenovirus 63 (ChAd63) and modified vaccinia virus Ankara (MVA) and used to immunize mice in a prime-boost regimen. We previously demonstrated that this regimen could provide partial protection against challenge with chimeric P. berghei parasites expressing PfUIS3. We now show that ChAd63-MVA PfUIS3 can also provide partial cross-species protection against challenge with wild-type P. berghei parasites. We also show that PfUIS3-specific cellular memory responses could be recalled in human volunteers exposed to P. falciparum parasites in a controlled human malaria infection study. When ChAd63-MVA PfUIS3 was coadministered with the vaccine candidate P. falciparum thrombospondin-related adhesion protein (PfTRAP) expressed in the ChAd63-MVA system, there was no significant change in immunogenicity to either vaccine. However, when mice were challenged with double chimeric P. berghei - P. falciparum parasites expressing both PfUIS3 and PfTRAP, vaccine efficacy was improved to 100% sterile protection. This synergistic effect was evident only when the two vaccines were mixed and administered at the same site. We have therefore demonstrated that vaccination with PfUIS3 can induce a consistent delay in patent parasitemia across mouse strains and against chimeric parasites expressing PfUIS3 as well as wild-type P. berghei when this vaccine is combined with another partially protective regimen (ChAd63-MVA PfTRAP), complete protection is induced.
Publisher: Cold Spring Harbor Laboratory
Date: 30-11-2018
DOI: 10.1101/481168
Abstract: In order to accelerate towards malaria elimination, improved targeting of limited resources is essential. A major gap in our elimination toolkit for Plasmodium vivax malaria is the identification of in iduals carrying arrested liver stages, called hypnozoites. These clinically silent but frequently relapsing hypnozoites are key to P. vivax persistence. Whilst hypnozoites cannot be directly detected, in iduals who have had recent exposure to P. vivax and have not been treated are likely to harbor these parasites. By measuring IgG antibody responses to over 300 P. vivax proteins, a panel of serological markers capable of detecting exposure to P. vivax infections in the prior 9-month period was identified and validated. Using antibody responses to 8 P. vivax proteins, 80% sensitivity and specificity for detecting recent infections were achieved in three independent studies conducted in Thailand, Brazil and the Solomon Islands. As these in iduals have a high likelihood of harboring hypnozoites, the suite of these 8 antibody responses can serve as biomarkers for the identification of in iduals who should be targeted for treatment with liver-stage drugs such as primaquine and tafenoquine in mass drug administration programs aimed at controlling and eliminating P. vivax malaria. The manuscript describes identification and validation of a novel panel of P. vivax proteins that can be used to detect recent exposure to P. vivax infections within the prior 9 months.
Publisher: Elsevier
Date: 2016
Publisher: Springer Science and Business Media LLC
Date: 04-08-2017
DOI: 10.1038/S41598-017-07246-0
Abstract: The majority of routinely given vaccines require two or three immunisations for full protective efficacy. Single dose vaccination has long been considered a key solution to improving the global immunisation coverage. Recent infectious disease outbreaks have further highlighted the need for vaccines that can achieve full efficacy after a single administration. Viral vectors are a potent immunisation platform, benefiting from intrinsic immuno-stimulatory features while retaining excellent safety profile through the use of non-replicating viruses. We investigated the scope for enhancing the protective efficacy of a single dose adenovirus-vectored malaria vaccine in a mouse model of malaria by co-administering it with vaccine adjuvants. Out of 11 adjuvants, only two, Abisco ® -100 and CoVaccineHT TM , enhanced vaccine efficacy and sterile protection following malaria challenge. The CoVaccineHT TM adjuvanted vaccine induced significantly higher proportion of antigen specific central memory CD8 + cells, and both adjuvants resulted in increased proportion of CD8 + T cells expressing the CD107a degranulation marker in the absence of IFNγ, TNFα and IL2 production. Our results show that the efficacy of vaccines designed to induce protective T cell responses can be positively modulated with chemical adjuvants and open the possibility of achieving full protection with a single dose immunisation.
Publisher: Cold Spring Harbor Laboratory
Date: 23-10-2021
DOI: 10.1101/2021.10.21.464164
Abstract: Plasmodium vivax is the dominant Plasmodium spp. causing the disease malaria in low-transmission regions outside of Africa. These regions often feature high proportions of asymptomatic patients with sub-microscopic parasitaemia and relapses. Naturally acquired antibody responses are induced after Plasmodium infection, providing partial protection against high parasitaemia and clinical episodes. However, previous work has failed to address the presence and maintenance of such antibody responses to P. vivax particularly in low-transmission regions. We followed 34 patients in western Thailand after symptomatic P. vivax infections to monitor antibody kinetics over 9 months, during which no recurrent infections occurred. We assessed total IgG, IgG subclass and IgM levels to up to 52 P. vivax proteins every 2-4 weeks using a multiplexed Luminex ® assay, and identified protein-specific variation in antibody longevity. Generally, an increase in antibody level was observed within 1-week post symptomatic infection, followed by an exponential decay of different rates. We observed mostly IgG1 dominance and IgG3 sub-dominance in this population. IgM responses followed similar kinetic patterns to IgG, with some proteins unexpectedly inducing long-lived IgM responses. We also monitored antibody responses against 27 IgG-immunogenic antigens in 30 asymptomatic in iduals from a similar region. Our results demonstrate that most antigens induced robust and long-lived total IgG responses following asymptomatic infections in the absence of (detected) boosting infections. Our work provides new insights into the development and maintenance of naturally acquired immunity to P. vivax and will guide the potential use of serology to indicate immune status and/or identify populations at risk.
Publisher: Elsevier BV
Date: 08-2012
DOI: 10.1038/MT.2012.25
Publisher: Cold Spring Harbor Laboratory
Date: 11-12-2021
DOI: 10.1101/2021.12.09.21266664
Abstract: Serological exposure markers are a promising tool for surveillance and targeted interventions for Plasmodium vivax malaria. P. vivax is closely related to the zoonotic parasite P. knowlesi , which also infects humans. P. vivax and P. knowlesi are co-endemic across much of South East Asia, making it important to design P. vivax serological markers that minimise cross-reactivity in this region. Our objective was to determine the degree of IgG antibody cross-reactivity against a panel of P. vivax serological markers in s les from human participants with P. knowlesi malaria. We observed higher levels of IgG antibody reactivity against P. vivax proteins that had high levels of sequence identity with their P. knowlesi ortholog. IgG reactivity peaked at 7 days post P. knowlesi infection and was short-lived, with minimal responses detected at 1-year post-infection. Using these data, we designed a panel of 8 P. vivax proteins with low-levels of cross-reactivity with P. knowlesi . This panel was able to accurately classify recent P. vivax infections whilst reducing misclassification of recent P. knowlesi infections.
Publisher: MDPI AG
Date: 09-10-2021
DOI: 10.3390/MPS4040072
Abstract: Serology tests are extremely useful for assessing whether a person has been infected with a pathogen. Since the onset of the COVID-19 pandemic, measurement of anti-SARS-CoV-2-specific antibodies has been considered an essential tool in identifying seropositive in iduals and thereby understanding the extent of transmission in communities. The Luminex system is a bead-based technology that has the capacity to assess multiple antigens simultaneously using very low s le volumes and is ideal for high-throughput studies. We have adapted this technology to develop a COVID-19 multi-antigen serological assay. This protocol described here carefully outlines recommended steps to optimize and establish this method for COVID-19-specific antibody measurement in plasma and in saliva. However, the protocol can easily be customized and thus the assay is broadly applicable to measure antibodies to other pathogens.
Publisher: Cambridge University Press (CUP)
Date: 07-01-2016
DOI: 10.1017/S0031182015000670
Abstract: Plasmodium vivax is the most geographically widespread of the malaria parasites causing human disease, yet it is comparatively understudied compared with Plasmodium falciparum. In this article we review what is known about naturally acquired immunity to P. vivax , and importantly, how this differs to that acquired against P. falciparum. Immunity to clinical P. vivax infection is acquired more quickly than to P. falciparum , and evidence suggests humans in endemic areas also have a greater capacity to mount a successful immunological memory response to this pathogen. Both of these factors give promise to the idea of a successful P. vivax vaccine. We review what is known about both the cellular and humoral immune response, including the role of cytokines, antibodies, immunoregulation, immune memory and immune dysfunction. Furthermore, we discuss where the future lies in terms of advancing our understanding of naturally acquired immunity to P. vivax , through the use of well-designed longitudinal epidemiological studies and modern tools available to immunologists.
Publisher: Springer Science and Business Media LLC
Date: 05-12-2017
DOI: 10.1038/S41598-017-17274-5
Abstract: A large research effort is currently underway to find an effective and affordable malaria vaccine. Tools that enable the rapid evaluation of protective immune responses are essential to vaccine development as they can provide selection criteria to rank order vaccine candidates. In this study we have revisited the Inhibition of Sporozoite Invasion (ISI) assay to assess the ability of antibodies to inhibit sporozoite infection of hepatocytes. By using GFP expressing sporozoites of the rodent parasite P . berghei we are able to robustly quantify parasite infection of hepatocyte cell lines by flow cytometry. In conjunction with recently produced transgenic P . berghei parasites that express P . falciparum sporozoite antigens, we have been able to use this assay to measure antibody mediated inhibition of sporozoite invasion against one of the lead malaria antigens P . falciparum CSP. By combining chimeric rodent parasites expressing P . falciparum antigens and a flow cytometric readout of infection, we are able to robustly assess vaccine-induced antibodies, from mice, rhesus macaques and human clinical trials, for their functional ability to block sporozoite invasion of hepatocytes.
Location: Germany
Location: United Kingdom of Great Britain and Northern Ireland
Location: United Kingdom of Great Britain and Northern Ireland
Location: Australia
No related grants have been discovered for Rhea Longley.