1
|
Owusu Sekyere S, Škrnjug-Yudov I, Ateba Ngoa U, Juárez Hernández M, Abiri OT, Komeh JP, Janneh Kaira M, Marenah E, Kercula JD, Smith K, Rassokhina O, Meyer H, Conrad C. Leveraging WHO's Global Benchmarking Tool to strengthen capacity in clinical trials oversight for public health emergencies: the GHPP VaccTrain model. Global Health 2022; 18:63. [PMID: 35725614 PMCID: PMC9207864 DOI: 10.1186/s12992-022-00854-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 06/08/2022] [Indexed: 12/02/2022] Open
Abstract
Background A stable, well-functioning and integrated national medicines regulatory system is a core component of health systems resilient against infectious disease outbreaks. In many low- and middle-income countries, however, sizable gaps exist in the emergency preparedness framework of national regulatory authorities (NRAs). RegTrain-VaccTrain is a project of Germany Ministry of Health’s Global Health Protection Programme that contributes to global efforts aimed at strengthening such regulatory systems by providing technical support and advice to partner NRAs. In this study, we probed the outputs of our capacity-strengthening activities for clinical trials oversight (CTO) to take stock of progress made and examine remaining priorities in order to provide specialized technical assistance in addressing them to improve operational readiness for emergencies. Method Data validated from NRA self-benchmarking results in 2017 and worksheet records of November 2021 were utilized to assess the emergency preparedness capacity for CTO in three VaccTrain partner NRAs (Liberia, Sierra Leone, The Gambia) before and after interventional capacity-strengthening partnership, using specific public health emergency-related (sub-)indicators of the WHO Global Benchmarking Tool. Results A generally weak and vulnerable structural framework for CTO characterized the emergency preparedness capacity in all three partner NRAs at baseline, thus putting their operational readiness for public health emergencies at risk. VaccTrain’s collaborative work was successful at supporting individual NRAs to develop the full spectrum of operational structures (including (draft) regulations, guidelines, and standard operating procedures) required to improve regulatory preparedness. A gap in the formal approval and implementation of developed legal documents in two of three NRAs still remains. Notwithstanding, a robust emergency framework now exists and the NRAs stand better prepared to respond to (future) locally-concerning health emergencies, during which time clinical trials activity was observed to heighten. Conclusions These results exemplify a north-south capacity-strengthening partnership model that effectively contributes in developing structures to enhance regulatory oversight and support expeditious product development in response to crises. They further underscore the equally critical role local/national processes play in facilitating the full implementation of developed structures. Supplementary Information The online version contains supplementary material available at 10.1186/s12992-022-00854-0.
Collapse
Affiliation(s)
- Solomon Owusu Sekyere
- Paul-Ehrlich-Institut, Federal Institute for Vaccines and Biomedicines, Unit G3: International Coordination/Regulatory Services, Paul-Ehrlich Str. 51-59, 63225, Langen, Germany. .,Paul-Ehrlich-Institut, Global Health Protection Programme (GHPP) RegTrain-VaccTrain, Langen, Germany.
| | - Ivana Škrnjug-Yudov
- Paul-Ehrlich-Institut, Federal Institute for Vaccines and Biomedicines, Unit G3: International Coordination/Regulatory Services, Paul-Ehrlich Str. 51-59, 63225, Langen, Germany.,Paul-Ehrlich-Institut, Global Health Protection Programme (GHPP) RegTrain-VaccTrain, Langen, Germany
| | - Ulysse Ateba Ngoa
- Paul-Ehrlich-Institut, Federal Institute for Vaccines and Biomedicines, Unit G3: International Coordination/Regulatory Services, Paul-Ehrlich Str. 51-59, 63225, Langen, Germany.,Paul-Ehrlich-Institut, Global Health Protection Programme (GHPP) RegTrain-VaccTrain, Langen, Germany
| | - Marcela Juárez Hernández
- Paul-Ehrlich-Institut, Federal Institute for Vaccines and Biomedicines, Unit G3: International Coordination/Regulatory Services, Paul-Ehrlich Str. 51-59, 63225, Langen, Germany.,Paul-Ehrlich-Institut, Global Health Protection Programme (GHPP) RegTrain-VaccTrain, Langen, Germany
| | - Onome T Abiri
- Pharmacovigilance and Clinical Trials Department, Pharmacy Board of Sierra Leone, Central Medical Stores Compound, New England Ville, Freetown, Sierra Leone
| | - James P Komeh
- Pharmacovigilance and Clinical Trials Department, Pharmacy Board of Sierra Leone, Central Medical Stores Compound, New England Ville, Freetown, Sierra Leone
| | | | - Essa Marenah
- Medicines Control Agency, 54 Kairaba Avenue, K.S.M.D, Serrekunda, Gambia
| | - Juwe Darnuwele Kercula
- Medicines Information & Clinical Trials, Liberia Medicines & Health Products Regulatory Authority (LMHRA), Monrovia, Liberia
| | - Keturah Smith
- Medicines Information & Clinical Trials, Liberia Medicines & Health Products Regulatory Authority (LMHRA), Monrovia, Liberia
| | - Olga Rassokhina
- Paul-Ehrlich-Institut, Federal Institute for Vaccines and Biomedicines, Unit G3: International Coordination/Regulatory Services, Paul-Ehrlich Str. 51-59, 63225, Langen, Germany.,Paul-Ehrlich-Institut, Global Health Protection Programme (GHPP) RegTrain-VaccTrain, Langen, Germany
| | - Heidi Meyer
- Paul-Ehrlich-Institut, Federal Institute for Vaccines and Biomedicines, Unit G3: International Coordination/Regulatory Services, Paul-Ehrlich Str. 51-59, 63225, Langen, Germany.,Paul-Ehrlich-Institut, WHO Collaborating Centre for the Standardization and Evaluation of Vaccines & Global Health Protection Programme (GHPP) RegTrain-VaccTrain, Langen, Germany
| | - Christoph Conrad
- Paul-Ehrlich-Institut, Federal Institute for Vaccines and Biomedicines, Unit G3: International Coordination/Regulatory Services, Paul-Ehrlich Str. 51-59, 63225, Langen, Germany.,Paul-Ehrlich-Institut, Global Health Protection Programme (GHPP) RegTrain-VaccTrain, Langen, Germany
| |
Collapse
|
2
|
Boussougou-Sambe ST, Woldearegai TG, Doumba-Ndalembouly AG, Ngossanga B, Mba RB, Edoa JR, Zinsou JF, Honkpehedji YJ, Ngoa UA, Dejon-Agobé JC, Borrmann S, Kremsner PG, Mordmüller B, Adegnika AA. Assessment of malaria transmission intensity and insecticide resistance mechanisms in three rural areas of the Moyen Ogooué Province of Gabon. Parasit Vectors 2022; 15:217. [PMID: 35725630 PMCID: PMC9208124 DOI: 10.1186/s13071-022-05320-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 05/10/2022] [Indexed: 12/03/2022] Open
Abstract
Background Vector control is considered to be the most successful component of malaria prevention programs and a major contributor to the reduction of malaria incidence over the last two decades. However, the success of this strategy is threatened by the development of resistance to insecticides and behavioural adaptations of vectors. The aim of this study was to monitor malaria transmission and the distribution of insecticide resistance genes in Anopheles populations from three rural areas of the Moyen Ogooué Province of Gabon. Methods Anopheles spp. were collected using human landing catches in Bindo, Nombakélé and Zilé, three villages located in the surroundings of Lambaréné, during both the rainy and dry seasons. Mosquitoes were identified morphologically, and DNA was extracted from heads and thoraces. Members of the Anopheles gambiae complex were identified by molecular methods using the PCR SINE200 protocol and by sequencing of the internal transcribed spacer 2 region. Taqman assays were used to determine Plasmodium infection and the presence of resistance alleles. Results Anopheles gambiae sensu lato (97.7%), An. moucheti (1.7%) and An. coustani (0.6%) were the three groups of species collected. Anopheles gambiae sensu stricto (98.5%) and An. coluzzii (1.5%) were the only species of the An. gambiae complex present in the collection. Of the 1235 Anopheles collected, 1193 were collected during the rainy season; these exhibited an exophagic behaviour, and consistently more mosquitoes were collected outdoor than indoor in the three study areas. Of the 1166 Anopheles screened, 26 (2.2%) were infected with Plasmodium species, specifically Plasmodium falciparum (66.7%), P. malariae (15.4%), P. ovale curtisi (11.5%) and P. ovale wallikeri (3.8%). Malaria transmission intensity was high in Zilé, with an average annual entomological inoculation rate (aEIR) of 243 infective bites per year, while aEIRs in Bindo and Nombakélé were 80.2 and 17 infective bites per year, respectively. Both the L1014F and L1014S mutations were present at frequencies > 95% but no Ace1G119S mutation was found. Conclusion Our results demonstrate that malaria transmission intensity is heterogeneous in these three rural areas of Moyen Ogooué Province, with areas of high transmission, such as Zilé. The exophagic behaviour of the mosquitoes as well as the high frequency of resistance mutations are serious challenges that need to be addressed by the deployment of control measures adapted to the local setting. Graphical Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-022-05320-9.
Collapse
Affiliation(s)
| | - Tamirat Gebru Woldearegai
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Eberhard Karls Universität, Tübingen, Germany.,German Center for Infection Research (DZIF), partner site Tübingen, Tübingen, Germany
| | | | | | - Romuald Beh Mba
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | | | - Jeannot Fréjus Zinsou
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Department of Parasitology, Leiden University Medical Center, Leiden, the Netherlands
| | - Yabo Josiane Honkpehedji
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Department of Parasitology, Leiden University Medical Center, Leiden, the Netherlands.,Fondation pour la Recherche Scientifique (FORS), Cotonou, Benin
| | | | - Jean Claude Dejon-Agobé
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, the Netherlands
| | - Steffen Borrmann
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Eberhard Karls Universität, Tübingen, Germany
| | - Peter G Kremsner
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Eberhard Karls Universität, Tübingen, Germany.,German Center for Infection Research (DZIF), partner site Tübingen, Tübingen, Germany
| | - Benjamin Mordmüller
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Eberhard Karls Universität, Tübingen, Germany.,Department of Medical Microbiology, Radboud University Medical Center (UMC), 6524 GA, Nijmegen, The Netherlands
| | - Ayôla A Adegnika
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Eberhard Karls Universität, Tübingen, Germany.,German Center for Infection Research (DZIF), partner site Tübingen, Tübingen, Germany.,Fondation pour la Recherche Scientifique (FORS), Cotonou, Benin
| |
Collapse
|
3
|
Dassah S, Adu B, Sirima SB, Mordmüller B, Ngoa UA, Atuguba F, Arthur FKN, Mensah BA, Kaddumukasa M, Bang P, Kremsner PG, Mategula D, Flach C, Milligan P, Theisen M. Extended follow-up of children in a phase2b trial of the GMZ2 malaria vaccine. Vaccine 2021; 39:4314-4319. [PMID: 34175127 DOI: 10.1016/j.vaccine.2021.06.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 06/02/2021] [Accepted: 06/10/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND The GMZ2/alum candidate malaria vaccine had an efficacy of 14% (95% confidence interval [CI]: 3.6%, 23%) against clinical malaria over 6 months of follow-up in a phase2b multicentre trial in children 1-5 years of age. Here we report the extended follow up of safety and efficacy over 2 years. METHODS A total of 1849 (GMZ2 = 926, rabies = 923) children aged 12-60 months were randomized to receive intramuscularly, either 3 doses of 100 μg GMZ2/alum or 3 doses of rabies vaccine as control 28 days apart. The children were followed-up for 24 months for clinical malaria episodes and adverse events. The primary endpoint was documented fever with parasitaemia of at least 5000/μL. RESULTS There were 2,062 malaria episodes in the GMZ2/alum group and 2,115 in the rabies vaccine group in the intention-to-treat analysis, vaccine efficacy (VE) of 6.5% (95%: CI -1.6%, 14.0%). In children aged 1-2 years at enrolment, VE was 3.6% (95 %CI: -9.1%, 14.8%) in the first year and -4.1% (95 %CI: -18.7%, 87%) in the second year. In children aged 3-5 years at enrolment VE was 19.9% (95 %CI: 7.7%, 30.4%) in the first year and 6.3% (95 %CI: -10.2%, 20.3%) in the second year (interaction by year, P = 0.025, and by age group, P = 0.085). A total of 187 (GMZ2 = 91, rabies = 96) serious adverse events were recorded in 167 individuals over the entire period of the study. There were no GMZ2 vaccine related serious adverse events. CONCLUSIONS GMZ2/alum was well tolerated. Follow-up over 2 years confirmed a low level of vaccine efficacy with slightly higher efficacy in older children, which suggests GMZ2 may act in concert with naturally acquired immunity.
Collapse
Affiliation(s)
- Sylvester Dassah
- Navrongo Health Research Centre, Navrongo, Ghana; Department of Biochemistry and Biotechnology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Bright Adu
- Department of Immunology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana
| | - Sodiomon B Sirima
- National de Recherche et de Formation sur le Paludisme, Burkina Faso
| | | | - Ulysse Ateba Ngoa
- Institute of Tropical Medicine, University of Tübingen, Germany; Centre de Recherches Médicales de Lambaréné (CERMEL), Gabon
| | | | - Fareed K N Arthur
- Department of Biochemistry and Biotechnology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Benedicta A Mensah
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana
| | | | - Peter Bang
- Department for Vaccine Development, Statens Serum Institut, Copenhagen, Denmark
| | - Peter G Kremsner
- National de Recherche et de Formation sur le Paludisme, Burkina Faso; Institute of Tropical Medicine, University of Tübingen, Germany
| | - Donnie Mategula
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, UK
| | - Clare Flach
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, UK
| | - Paul Milligan
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, UK
| | - Michael Theisen
- Department for Congenital Disorders, Statens Serum Institut, Copenhagen, Denmark; Centre for Medical Parasitology at Department of International Health, Immunology, and Microbiology, University of Copenhagen, and Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Denmark.
| |
Collapse
|
4
|
Nouatin O, Mengue JB, Dejon-Agobé JC, Fendel R, Ibáñez J, Ngoa UA, Edoa JR, Adégbité BR, Honkpéhédji YJ, Zinsou JF, Hounkpatin AB, Moutairou K, Homoet A, Esen M, Kreidenweiss A, Hoffman SL, Theisen M, Luty AJF, Lell B, Agnandji ST, Mombo-Ngoma G, Ramharter M, Kremsner P, Mordmüller B, Adegnika AA. Exploratory analysis of the effect of helminth infection on the immunogenicity and efficacy of the asexual blood-stage malaria vaccine candidate GMZ2. PLoS Negl Trop Dis 2021; 15:e0009361. [PMID: 34061838 PMCID: PMC8195366 DOI: 10.1371/journal.pntd.0009361] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 06/11/2021] [Accepted: 04/03/2021] [Indexed: 11/18/2022] Open
Abstract
Background Helminths can modulate the host immune response to Plasmodium falciparum and can therefore affect the risk of clinical malaria. We assessed here the effect of helminth infections on both the immunogenicity and efficacy of the GMZ2 malaria vaccine candidate, a recombinant protein consisting of conserved domains of GLURP and MSP3, two asexual blood-stage antigens of P. falciparum. Controlled human malaria infection (CHMI) was used to assess the efficacy of the vaccine. Methodology In a randomized, double-blind Phase I clinical trial, fifty, healthy, lifelong malaria-exposed adult volunteers received three doses of GMZ2 adjuvanted with either Cationic Adjuvant Formulation (CAF) 01 or Alhydrogel, or a control vaccine (Rabies) on days (D) 0, D28 and D56, followed by direct venous inoculation (DVI) of 3,200 P. falciparum sporozoites (PfSPZ Challenge) approximately 13 weeks after last vaccination to assess vaccine efficacy. Participants were followed-up on a daily basis with clinical examinations and thick blood smears to monitor P. falciparum parasitemia for 35 days. Malaria was defined as the presence of P. falciparum parasites in the blood associated with at least one symptom that can be associated to malaria over 35 days following DVI of PfSPZ Challenge. Soil-transmitted helminth (STH) infection was assessed by microscopy and by polymerase chain reaction (PCR) on stool, and Schistosoma infection was assessed by microscopy on urine. Participants were considered as infected if positive for any helminth either by PCR and/or microscopy at D0 and/or at D84 (Helm+) and were classified as mono-infection or co-infection. Total vaccine-specific IgG concentrations assessed on D84 were analysed as immunogenicity outcome. Main findings The helminth in mono-infection, particularly Schistosoma haematobium and STH were significantly associated with earlier malaria episodes following CHMI, while no association was found in case of coinfection. In further analyses, the anti-GMZ2 IgG concentration on D84 was significantly higher in the S. haematobium-infected and significantly lower in the Strongyloides stercoralis-infected groups, compared to helminth-negative volunteers. Interesting, in the absence of helminth infection, a high anti-GMZ2 IgG concentration on D84 was significantly associated with protection against malaria. Conclusions Our results suggest that helminth infection may reduce naturally acquired and vaccine-induced protection against malaria. Vaccine-specific antibody concentrations on D84 may be associated with protection in participants with no helminth infection. These results suggest that helminth infection affect malaria vaccine immunogenicity and efficacy in helminth endemic countries. Helminths, mainly because of their immune regulatory effects, are able to impact the response induced by vaccines. In the context of clinical trial designs that measure accrual of natural infections during follow up or outcome of controlled human malaria infection (CHMI), their effect on vaccine efficacy can be measured. Indeed, most of such clinical trials on malaria vaccine candidates conducted in Africa, especially where the prevalence of helminths is high, have shown a certain limit in their efficacy and immunogenicity, as compared to results observed in European and U.S volunteers. The present analysis assessed the effect of helminths on GMZ2, a malaria vaccine candidate. We found a high level of anti-GMZ2 antibodies among volunteers not infected with helminths and protected against CHMI, indicating efficacy of the candidate vaccine in this population. We found a species-dependent effect of helminths on the level of post-immunization GMZ2-specific IgG concentration, and an association of helminths with an early onset of malaria in CHMI. Our findings reveal that helminths are associated with immunogenicity and may decrease the protective effect of antibodies induced by vaccination. Helminth infection status shall be determined when measuring the immunogenicity and efficacy of malaria vaccine candidates in helminth endemic countries.
Collapse
Affiliation(s)
- Odilon Nouatin
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany.,Département de Biochimie et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d'Abomey-Calavi, Cotonou, Bénin
| | | | - Jean Claude Dejon-Agobé
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Amsterdam University Medical Centers, Amsterdam Infection & Immunity, Amsterdam Public Health, University of Amsterdam, Amsterdam, The Netherlands
| | - Rolf Fendel
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany.,German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany
| | - Javier Ibáñez
- Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany
| | | | | | - Bayodé Roméo Adégbité
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Amsterdam University Medical Centers, Amsterdam Infection & Immunity, Amsterdam Public Health, University of Amsterdam, Amsterdam, The Netherlands.,Fondation pour la Recherche Scientifique, Cotonou, Bénin
| | - Yabo Josiane Honkpéhédji
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Fondation pour la Recherche Scientifique, Cotonou, Bénin.,Department of Parasitology, Leiden University Medical Centre (LUMC), Leiden, The Netherlands
| | - Jeannot Fréjus Zinsou
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Fondation pour la Recherche Scientifique, Cotonou, Bénin.,Department of Parasitology, Leiden University Medical Centre (LUMC), Leiden, The Netherlands
| | - Aurore Bouyoukou Hounkpatin
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany
| | - Kabirou Moutairou
- Département de Biochimie et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d'Abomey-Calavi, Cotonou, Bénin
| | - Andreas Homoet
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany
| | - Meral Esen
- Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany.,German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany
| | - Andrea Kreidenweiss
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany.,German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany
| | | | - Michael Theisen
- Department of Congenital Disorders, Statens Serum Institut, Copenhagen, Denmark.,Centre for Medical Parasitology at Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Adrian J F Luty
- Centre d'Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l'Enfance, Calavi, Bénin.,Université de Paris, MERIT, IRD, Paris, France
| | - Bertrand Lell
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Department of Medicine I, Division of Infectious Diseases and Tropical Medicine, Medical University of Vienna, Vienna, Austria
| | - Selidji Todagbe Agnandji
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany.,German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany
| | - Ghyslain Mombo-Ngoma
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany.,Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I, Department of Medicine, University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany
| | - Michael Ramharter
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I, Department of Medicine, University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany
| | - Peter Kremsner
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany.,German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany
| | - Benjamin Mordmüller
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany.,German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany.,Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Ayôla Akim Adegnika
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany.,German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany.,Fondation pour la Recherche Scientifique, Cotonou, Bénin.,Department of Parasitology, Leiden University Medical Centre (LUMC), Leiden, The Netherlands
| |
Collapse
|
5
|
Nouatin O, Ateba Ngoa U, Ibáñez J, Dejon-Agobe JC, Mordmüller B, Edoa JR, Mougeni F, Brückner S, Bouyoukou Hounkpatin A, Esen M, Theisen M, Moutairou K, Hoffman SL, Issifou S, Luty AJF, Loembe MM, Agnandji ST, Lell B, Kremsner PG, Adegnika AA. Effect of immune regulatory pathways after immunization with GMZ2 malaria vaccine candidate in healthy lifelong malaria-exposed adults. Vaccine 2020; 38:4263-4272. [PMID: 32386747 DOI: 10.1016/j.vaccine.2020.04.046] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 04/08/2020] [Accepted: 04/20/2020] [Indexed: 01/01/2023]
Abstract
BACKGROUND Despite appreciable immunogenicity in malaria-naive populations, many candidate malaria vaccines are considerably less immunogenic in malaria-exposed populations. This could reflect induction of immune regulatory mechanisms involving Human Leukocyte Antigen G (HLA-G), regulatory T (Treg), and regulatory B (Breg) cells. Here, we addressed the question whether there is correlation between these immune regulatory pathways and both plasmablast frequencies and vaccine-specific IgG concentrations. METHODS Fifty Gabonese adults with lifelong exposure to Plasmodium spp were randomized to receive three doses of either 30 µg or 100 µg GMZ2-CAF01, or 100 µg GMZ2-alum, or control vaccine (rabies vaccine) at 4-week intervals. Only plasma and peripheral blood mononuclear cells isolated from blood samples collected before (D0) and 28 days after the third vaccination (D84) of 35 participants were used to measure sHLA-G levels and anti-GMZ2 IgG concentrations, and to quantify Treg, Breg and plasmablast cells. Vaccine efficacy was assessed using controlled human malaria infection (CHMI) by direct venous inoculation of Plasmodium falciparum sporozoites (PfSPZ Challenge). RESULTS The sHLA-G concentration increased from D0 to D84 in all GMZ2 vaccinated participants and in the control group, whereas Treg frequencies increased only in those receiving 30 µg or 100 µg GMZ2-CAF01. The sHLA-G level on D84 was associated with a decrease of the anti-GMZ2 IgG concentration, whereas Treg frequencies on D0 or on D84, and Breg frequency on D84 were associated with lower plasmablast frequencies. Importantly, having a D84:D0 ratio of sHLA-G above the median was associated with an increased risk of P. falciparum infection after sporozoites injection. CONCLUSION Regulatory immune responses are induced following immunization. Stronger sHLA-G and Treg immune responses may suppress vaccine induced immune responses, and the magnitude of the sHLA-G response increased the risk of Plasmodium falciparum infection after CHMI. These findings could have implications for the design and testing of malaria vaccine candidates in semi-immune individuals.
Collapse
Affiliation(s)
- Odilon Nouatin
- Centre de Recherches Médicales de Lambaréné, BP: 242 Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tubingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany; Germany; German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany; Département de Biochimie et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d'Abomey-Calavi, Cotonou, Benin.
| | - Ulysse Ateba Ngoa
- Centre de Recherches Médicales de Lambaréné, BP: 242 Lambaréné, Gabon.
| | - Javier Ibáñez
- Institut für Tropenmedizin, Universität Tubingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Jean Claude Dejon-Agobe
- Centre de Recherches Médicales de Lambaréné, BP: 242 Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tubingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Benjamin Mordmüller
- Centre de Recherches Médicales de Lambaréné, BP: 242 Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tubingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany; Germany; German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany.
| | - Jean Ronald Edoa
- Centre de Recherches Médicales de Lambaréné, BP: 242 Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tubingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany.
| | - Fabrice Mougeni
- Centre de Recherches Médicales de Lambaréné, BP: 242 Lambaréné, Gabon
| | - Sina Brückner
- Institut für Tropenmedizin, Universität Tubingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany.
| | - Aurore Bouyoukou Hounkpatin
- Centre de Recherches Médicales de Lambaréné, BP: 242 Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tubingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Meral Esen
- Centre de Recherches Médicales de Lambaréné, BP: 242 Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tubingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany; Germany; German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany.
| | - Michael Theisen
- Department for Congenital Disorders, Statens Serum Institut, Copenhagen, Denmark and Centre for Medical Parasitology at Department of International Health, Immunology and Microbiology, University of Copenhagen, and Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Denmark.
| | - Kabirou Moutairou
- Département de Biochimie et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d'Abomey-Calavi, Cotonou, Benin.
| | | | - Saadou Issifou
- Fondation pour la Recherche Scientifique, 72 BP45 Cotonou, Benin.
| | - Adrian J F Luty
- Centre d'Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l'Enfance, Faculté des Sciences de la Santé, Université d'Abomey-Calavi, Cotonou, MERIT UMR D216, Benin; Université de Paris, MERIT, IRD, Paris, France.
| | - Marguerite M Loembe
- Centre de Recherches Médicales de Lambaréné, BP: 242 Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tubingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany; Germany; German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany.
| | - Selidji Todagbé Agnandji
- Centre de Recherches Médicales de Lambaréné, BP: 242 Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tubingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany; Germany; German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany.
| | - Bertrand Lell
- Centre de Recherches Médicales de Lambaréné, BP: 242 Lambaréné, Gabon; Department of Medicine I, Division of Infectious Diseases and Tropical Medicine, Medical University of Vienna, Vienna, Austria.
| | - Peter G Kremsner
- Centre de Recherches Médicales de Lambaréné, BP: 242 Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tubingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany; Germany; German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany.
| | - Ayôla Akim Adegnika
- Centre de Recherches Médicales de Lambaréné, BP: 242 Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tubingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany; Germany; German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany; Leiden University Medical Centre (LUMC), 2333 ZA Leiden, the Netherlands.
| |
Collapse
|
6
|
Ngoa UA, Schaumburg F, Adegnika AA, Kösters K, Möller T, Gaus E, Fernandes JF, Alabi A, Issifou S, Becker K, Grobusch MP, Kremsner PG, Lell B. Corrigendum to "Epidemiology and population structure of Staphylococcus aureus in various population groups from a rural and semi urban area in Gabon, Central Africa" [Acta Trop. 124 (2012) 42-47]. Acta Trop 2018; 185:422. [PMID: 29887385 DOI: 10.1016/j.actatropica.2018.05.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
7
|
Gebru T, Ajua A, Theisen M, Esen M, Ngoa UA, Issifou S, Adegnika AA, Kremsner PG, Mordmüller B, Held J. Recognition of Plasmodium falciparum mature gametocyte-infected erythrocytes by antibodies of semi-immune adults and malaria-exposed children from Gabon. Malar J 2017; 16:176. [PMID: 28446190 PMCID: PMC5406886 DOI: 10.1186/s12936-017-1827-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 04/19/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Transmission of malaria from man to mosquito depends on the presence of gametocytes, the sexual stage of Plasmodium parasites in the infected host. Naturally acquired antibodies against gametocytes exist and may play a role in controlling transmission by limiting the gametocyte development in the circulation or by interrupting gamete development and fertilization in the mosquito following ingestion. So far, most studies on antibody responses to sexual stage antigens have focused on a subset of gametocyte-surface antigens, even though inhibitory Ab responses to other gametocyte antigens might also play a role in controlling gametocyte density and fertility. Limited information is available on natural antibody response to the surfaces of gametocyte-infected erythrocytes. METHODS Ab responses to surface antigens of erythrocytes infected by in vitro differentiated Plasmodium falciparum mature gametocytes were investigated in sera of semi-immune adults and malaria-exposed children. In addition, the effect of immunization with GMZ2, a blood stage malaria vaccine candidate, and the effect of intestinal helminth infection on the development of immunity to gametocytes of P. falciparum was evaluated in malaria-exposed children and adults from Gabon. Serum samples from two Phase I clinical trials conducted in Gabon were analysed by microscopic and flow-cytometric immunofluorescence assay. RESULTS Adults had a higher Ab response compared to children. Ab reactivity was significantly higher after fixation and permeabilization of parasitized erythrocytes. Following vaccination with the malaria vaccine candidate GMZ2, anti-gametocyte Ab concentration decreased in adults compared to baseline. Ab response to whole asexual stage antigens had a significant but weak positive correlation to anti-gametocyte Ab responses in adults, but not in children. Children infected with Ascaris lumbricoides had a significantly higher anti-gametocyte Ab response compared to non-infected children. CONCLUSION The current data suggest that antigens exposed on the gametocyte-infected red blood cells are recognized by serum antibodies from malaria-exposed children and semi-immune adults. This anti-gametocyte immune response may be influenced by natural exposure and vaccination. Modulation of the natural immune response to gametocytes by co-infecting parasites should be investigated further and may have an important impact on malaria control strategies.
Collapse
Affiliation(s)
- Tamirat Gebru
- Institute of Tropical Medicine, University of Tübingen, Wilhelmstraße 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon.,German Centre for Infection Research (DZIF), Partner Site Lambaréné, Gabon.,Department of Medical Laboratory Sciences, College of Medical and Health Sciences, Haramaya University, Harar, Ethiopia
| | - Anthony Ajua
- Institute of Tropical Medicine, University of Tübingen, Wilhelmstraße 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany
| | - Michael Theisen
- Department for Congenital Disorders, Statens Serum Institut, Copenhagen, Denmark.,Center for Medical Parasitology at Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Meral Esen
- Institute of Tropical Medicine, University of Tübingen, Wilhelmstraße 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon.,German Centre for Infection Research (DZIF), Partner Site Lambaréné, Gabon
| | - Ulysse Ateba Ngoa
- Institute of Tropical Medicine, University of Tübingen, Wilhelmstraße 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon.,German Centre for Infection Research (DZIF), Partner Site Lambaréné, Gabon.,Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
| | - Saadou Issifou
- Institute of Tropical Medicine, University of Tübingen, Wilhelmstraße 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany.,Fondation pour la Recherche Scientifique (FORS), Cotonou, Benin
| | - Ayola A Adegnika
- Institute of Tropical Medicine, University of Tübingen, Wilhelmstraße 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon.,German Centre for Infection Research (DZIF), Partner Site Lambaréné, Gabon.,Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
| | - Peter G Kremsner
- Institute of Tropical Medicine, University of Tübingen, Wilhelmstraße 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon.,German Centre for Infection Research (DZIF), Partner Site Lambaréné, Gabon
| | - Benjamin Mordmüller
- Institute of Tropical Medicine, University of Tübingen, Wilhelmstraße 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon.,German Centre for Infection Research (DZIF), Partner Site Lambaréné, Gabon
| | - Jana Held
- Institute of Tropical Medicine, University of Tübingen, Wilhelmstraße 27, 72074, Tübingen, Germany. .,German Centre for Infection Research (DZIF), Partner Site Tübingen, Germany. .,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon. .,German Centre for Infection Research (DZIF), Partner Site Lambaréné, Gabon.
| |
Collapse
|
8
|
Nouatin O, Ngoa UA, Dejon JC, Edoa JR, Homoet A, Engelhon JE, Massinga-Louembe M, Esen M, Theisen M, Sim KL, Richie T, Luty AJ, Moutairou K, Hoffman S, Kremsner P, Lell B, Mordmüller B, Adegnika A. SOLUBLE HLA-G LEVEL EFFECT ON GMZ2 SPECIFIC IgG PRODUCTION AFTER IMMUNISATION. BMJ Glob Health 2017. [DOI: 10.1136/bmjgh-2016-000260.82] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
|
9
|
Agobé JCD, Zinsou FJ, Honkpehedji J, Ngoa UA, Kremsner P, Adegnika A. EFFECT OF SCHISTOSOMA HAEMATOBIUM INFECTION ON PLASMODIUM FALCIPARUMMALARIA BURDEN IN LAMBARÉNÉ, GABON. BMJ Glob Health 2017. [DOI: 10.1136/bmjgh-2016-000260.158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
|
10
|
Ateba Ngoa U, Zinsou JF, Kassa RFK, Ngoune Feugap E, Honkpehedji YJ, Massinga-Loembe M, Kenguele Moundounga H, Nkoma Mouima AM, Mbenkep LH, Wammes LJ, Mbow M, Kruize Y, Mombo-Ngoma G, Bouyoukou Hounkpatin AL, Dejon Agobe JC, Saadou I, Lell B, Smits H, Kremsner PG, Yazdanbakhsh M, Adegnika AA. Assessment of the effect of Schistosoma haematobium co infection on malaria parasites and immune responses in rural populations in Gabon: study protocol. Springerplus 2014; 3:388. [PMID: 25120947 PMCID: PMC4128953 DOI: 10.1186/2193-1801-3-388] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 07/15/2014] [Indexed: 02/05/2023]
Abstract
Background Malaria and helminth co infection are common in tropical and subtropical areas where they affect the life of millions of people. While both helminth and malaria parasites have immunomodulatory activities, little is known about the consequence of co-infections on malaria antigen specific immune responses. Method/Design This study will be conducted in two rural areas of the Moyen Ogooué province in Gabon, endemic for both Plasmodium falciparum and Schistosoma haematobium infections. Participants, 5 to 50 years old, will be enrolled and grouped according to their infection status. S. haematobium and malaria parasites will be detected, demographic and clinical data will be recorded and blood will be collected for hematological as well as for immunological assays. The level of antibody specific to Plasmodium falciparum blood stage and gametocyte antigens will be measured using ELISA. PBMC will be isolated for phenotyping of different T cell subsets ex vivo by flow cytometry and for culture and cytokine response assessment. Discussion We will provide a comprehensive picture of the interaction between schistosomes and malaria parasites which co-localize in peripheral blood. We will test the hypothesis that schistosome infection has an impact on specific humoral as well as on cellular immune responses to malaria antigens.
Collapse
Affiliation(s)
- Ulysse Ateba Ngoa
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany ; Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Jeannot Fréjus Zinsou
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Roland Fabrice Kassa Kassa
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Eliane Ngoune Feugap
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Yabo Josiane Honkpehedji
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Marguerite Massinga-Loembe
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany ; Faculté de Médecine, Université des Sciences de la Santé de Libreville, BP: 4009, Libreville, Gabon
| | - Hilaire Kenguele Moundounga
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Anne Marie Nkoma Mouima
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Lima Honorine Mbenkep
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Linda Judith Wammes
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Moustapha Mbow
- Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands ; Immunology Unit of the Laboratory of Bacteriology and Virology of Aristide Le Dantec Teaching Hospital, 30 Avenue Pasteur, BP 7325, Dakar, Senegal ; Institute of Tropical Medicine of Antwerp, Nationalestraat 155, 2000 Antwerp, Belgium
| | - Yvonne Kruize
- Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Ghyslain Mombo-Ngoma
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany ; Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands ; Faculté de Médecine, Université des Sciences de la Santé de Libreville, BP: 4009, Libreville, Gabon
| | - Aurore Larissa Bouyoukou Hounkpatin
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Jean Claude Dejon Agobe
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Issifou Saadou
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Bertrand Lell
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Hermelijn Smits
- Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Peter Gottfried Kremsner
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany
| | - Maria Yazdanbakhsh
- Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Ayola Akim Adegnika
- Centre de Recherches Médicales de Lambaréné, BP: 118, Lambaréné, Gabon ; Institut für Tropenmedizin, Universität Tübingen, Wilhelmstraβe 27, D-72074 Tübingen, Germany ; Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| |
Collapse
|
11
|
Scherbaum M, Kösters K, Mürbeth RE, Ngoa UA, Kremsner PG, Lell B, Alabi A. Incidence, pathogens and resistance patterns of nosocomial infections at a rural hospital in Gabon. BMC Infect Dis 2014; 14:124. [PMID: 24592922 PMCID: PMC3943987 DOI: 10.1186/1471-2334-14-124] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2013] [Accepted: 02/19/2014] [Indexed: 12/28/2022] Open
Abstract
Background Nosocomial infections pose substantial risk to patients receiving care in hospitals. In Africa, this problem is aggravated by inadequate infection control due to poor hygiene, resource and structural constraints, deficient surveillance data and lack of awareness regarding nosocomial infections. We carried out this study to determine the incidence and spectrum of nosocomial infections, pathogens and antibiotic resistance patterns in a tertiary regional hospital in Lambaréné, Gabon. Methods This prospective case study was carried out over a period of six months at the Albert Schweitzer Hospital, Lambaréné, Gabon. All patients admitted to the departments of surgery, gynecology/obstetrics and internal medicine were screened daily for signs and symptoms of hospital-acquired infections. Results A total of 2925 patients were screened out of which 46 nosocomial infections (1.6%) were diagnosed. These comprised 20 (44%) surgical-site infections, 12 (26%) urinary-tract infections, 9 (20%) bacteraemias and 5 (11%) other infections. High rates of nosocomial infections were found after hysterectomies (12%) and Caesarean sections (6%). Most frequent pathogens were Staphylococcus aureus and Escherichia coli. Eight (40%) of 20 identified E. coli and Klebsiella spp. strains were ESBL-producing organisms. Conclusion The cumulative incidence of nosocomial infections in this study was low; however, the high rates of surgical site infections and multi-resistant pathogens necessitate urgent comprehensive interventions of infection control.
Collapse
Affiliation(s)
| | | | | | | | | | - Bertrand Lell
- Centre de Recherches Medicales de Lambarene, Albert Schweitzer Hospital, PB 118 Lambaréné, Gabon.
| | | |
Collapse
|
12
|
Esen M, Mordmüller B, de Salazar PM, Adegnika AA, Agnandji ST, Schaumburg F, Hounkpatin AB, Brückner S, Theisen M, Bélard S, Ngoa UA, Issifou S, Yazdanbakhsh M, Kremsner PG. Reduced antibody responses against Plasmodium falciparum vaccine candidate antigens in the presence of Trichuris trichiura. Vaccine 2012; 30:7621-4. [DOI: 10.1016/j.vaccine.2012.10.026] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 09/18/2012] [Accepted: 10/05/2012] [Indexed: 10/27/2022]
|
13
|
|
14
|
Meurs L, Labuda L, Amoah AS, Mbow M, Ngoa UA, Boakye DA, Mboup S, Dièye TN, Mountford AP, Turner JD, Kremsner PG, Polman K, Yazdanbakhsh M, Adegnika AA. Enhanced pro-inflammatory cytokine responses following Toll-like-receptor ligation in Schistosoma haematobium-infected schoolchildren from rural Gabon. PLoS One 2011; 6:e24393. [PMID: 21931706 PMCID: PMC3169609 DOI: 10.1371/journal.pone.0024393] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 08/09/2011] [Indexed: 11/18/2022] Open
Abstract
Background Schistosoma infection is thought to lead to down-regulation of the host's immune response. This has been shown for adaptive immune responses, but the effect on innate immunity, that initiates and shapes the adaptive response, has not been extensively studied. In a first study to characterize these responses, we investigated the effect of Schistosoma haematobium infection on cytokine responses of Gabonese schoolchildren to a number of Toll-like receptor (TLR) ligands. Methodology Peripheral blood mononuclear cells (PBMCs) were collected from S. haematobium-infected and uninfected schoolchildren from the rural area of Zilé in Gabon. PBMCs were incubated for 24 h and 72 h with various TLR ligands, as well as schistosomal egg antigen (SEA) and adult worm antigen (AWA). Pro-inflammatory TNF-α and anti-inflammatory/regulatory IL-10 cytokine concentrations were determined in culture supernatants. Principal Findings Infected children produced higher adaptive IL-10 responses than uninfected children against schistosomal antigens (72 h incubation). On the other hand, infected children had higher TNF-α responses than uninfected children and significantly higher TNF-α to IL-10 ratios in response to FSL-1 and Pam3, ligands of TLR2/6 and TLR2/1 respectively. A similar trend was observed for the TLR4 ligand LPS while Poly(I:C) (Mda5/TLR3 ligand) did not induce substantial cytokine responses (24 h incubation). Conclusions This pilot study shows that Schistosoma-infected children develop a more pro-inflammatory TLR2-mediated response in the face of a more anti-inflammatory adaptive immune response. This suggests that S. haematobium infection does not suppress the host's innate immune system in the context of single TLR ligation.
Collapse
Affiliation(s)
- Lynn Meurs
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Bélard S, Issifou S, Hounkpatin AB, Schaumburg F, Ngoa UA, Esen M, Fendel R, de Salazar PM, Mürbeth RE, Milligan P, Imbault N, Imoukhuede EB, Theisen M, Jepsen S, Noor RA, Okech B, Kremsner PG, Mordmüller B. A randomized controlled phase Ib trial of the malaria vaccine candidate GMZ2 in African children. PLoS One 2011; 6:e22525. [PMID: 21829466 PMCID: PMC3145647 DOI: 10.1371/journal.pone.0022525] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Accepted: 06/23/2011] [Indexed: 12/04/2022] Open
Abstract
Background GMZ2 is a fusion protein of Plasmodium falciparum merozoite surface protein 3 (MSP3) and glutamate rich protein (GLURP) that mediates an immune response against the blood stage of the parasite. Two previous phase I clinical trials, one in naïve European adults and one in malaria-exposed Gabonese adults showed that GMZ2 was well tolerated and immunogenic. Here, we present data on safety and immunogenicity of GMZ2 in one to five year old Gabonese children, a target population for future malaria vaccine efficacy trials. Methodology/Principal Findings Thirty children one to five years of age were randomized to receive three doses of either 30 µg or 100 µg of GMZ2, or rabies vaccine. GMZ2, adjuvanted in aluminum hydroxide, was administered on Days 0, 28 and 56. All participants received a full course of their respective vaccination and were followed up for one year. Both 30 µg and 100 µg GMZ2 vaccine doses were well tolerated and induced antibodies and memory B-cells against GMZ2 as well as its antigenic constituents MSP3 and GLURP. After three doses of vaccine, the geometric mean concentration of antibodies to GMZ2 was 19-fold (95%CI: 11,34) higher in the 30 µg GMZ2 group than in the rabies vaccine controls, and 16-fold (7,36) higher in the 100 µg GMZ2 group than the rabies group. Geometric mean concentration of antibodies to MSP3 was 2.7-fold (1.6,4.6) higher in the 30 µg group than in the rabies group and 3.8-fold (1.5,9.6) higher in the 100 µg group. Memory B-cells against GMZ2 developed in both GMZ2 vaccinated groups. Conclusions/Significance Both 30 µg as well as 100 µg intramuscular GMZ2 are immunogenic, well tolerated, and safe in young, malaria-exposed Gabonese children. This result confirms previous findings in naïve and malaria-exposed adults and supports further clinical development of GMZ2. Trial Registration ClinicalTrials.gov NCT00703066
Collapse
Affiliation(s)
- Sabine Bélard
- Medical Research Unit, Albert Schweitzer Hospital, Lambaréné, Gabon
| | - Saadou Issifou
- Medical Research Unit, Albert Schweitzer Hospital, Lambaréné, Gabon
| | | | | | | | - Meral Esen
- Medical Research Unit, Albert Schweitzer Hospital, Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Rolf Fendel
- Medical Research Unit, Albert Schweitzer Hospital, Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | | | | | - Paul Milligan
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Nathalie Imbault
- European Malaria Vaccine Initiative, Statens Serum Institut, Copenhagen, Denmark
| | | | - Michael Theisen
- Department of Clinical Biochemistry and Immunology, Statens Serum Institut and Centre for Medical Parasitology at the Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | | | | | - Brenda Okech
- African Malaria Network Trust, Dar es Salaam, Tanzania
| | - Peter G. Kremsner
- Medical Research Unit, Albert Schweitzer Hospital, Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Benjamin Mordmüller
- Medical Research Unit, Albert Schweitzer Hospital, Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- * E-mail:
| |
Collapse
|
16
|
Schaumburg F, Köck R, Friedrich AW, Soulanoudjingar S, Ngoa UA, von Eiff C, Issifou S, Kremsner PG, Herrmann M, Peters G, Becker K. Population structure of Staphylococcus aureus from remote African Babongo Pygmies. PLoS Negl Trop Dis 2011; 5:e1150. [PMID: 21572985 PMCID: PMC3091839 DOI: 10.1371/journal.pntd.0001150] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Accepted: 03/09/2011] [Indexed: 12/15/2022] Open
Abstract
Background Pandemic community-acquired methicillin-resistant Staphylococcus aureus isolates (CA-MRSA) predominantly encode the Panton-Valentine leukocidin (PVL), which can be associated with severe infections. Reports from non-indigenous Sub-Saharan African populations revealed a high prevalence of PVL-positive isolates. The objective of our study was to investigate the S. aureus carriage among a remote indigenous African population and to determine the molecular characteristics of the isolates, particularly those that were PVL-positive. Methodology/Principal Findings Nasal S. aureus carriage and risk factors of colonization were systematically assessed in remote Gabonese Babongo Pygmies. Susceptibility to antibiotics, possession of toxin-encoding genes (i.e., PVL, enterotoxins, and exfoliative toxins), S. aureus protein A (spa) types and multi-locus sequence types (MLST) were determined for each isolate. The carriage rate was 33%. No MRSA was detected, 61.8% of the isolates were susceptible to penicillin. Genes encoding PVL (55.9%), enterotoxin B (20.6%), exfoliative toxin D (11.7%) and the epidermal cell differentiation inhibitor B (11.7%) were highly prevalent. Thirteen spa types were detected and were associated with 10 STs predominated by ST15, ST30, ST72, ST80, and ST88. Conclusions The high prevalence of PVL-positive isolates among Babongo Pygmies demands our attention as PVL can be associated with necrotinzing infection and may increase the risk of severe infections in remote Pygmy populations. Many S. aureus isolates from Babongo Pygmies and pandemic CA-MRSA-clones have a common genetic background. Surveillance is needed to control the development of resistance to antibiotic drugs and to assess the impact of the high prevalence of PVL in indigenous populations. Staphylococcus aureus is a bacterium that colonizes humans worldwide. The anterior nares are its main ecological niche. Carriers of S. aureus are at a higher risk of developing invasive infections. Few reports indicated a different clonal structure and profile of virulence factors in S. aureus isolates from Sub-Saharan Africa. As there are no data about isolates from remote indigenous African populations, we conducted a cross-sectional survey of S. aureus nasal carriage in Gabonese Babongo Pygmies. The isolates were characterized regarding their susceptibility to antibiotic agents, possession of virulence factors and clonal lineage. While similar carriage rates were found in populations of industrialized countries, isolates that encode the genes for the Panton-Valentine leukocidin (PVL) were clearly more prevalent than in European countries. Of interest, many methicillin-susceptible S. aureus isolates from Babongo Pygmies showed the same genetic background as pandemic methicillin-resistant S. aureus (MRSA) clones. We advocate a surveillance of S. aureus in neglected African populations to control the development of resistance to antibiotic drugs with particular respect to MRSA and to assess the impact of the high prevalence of PVL-positive isolates.
Collapse
Affiliation(s)
- Frieder Schaumburg
- Institute of Medical Microbiology, University of Münster, Münster, Germany.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Adegnika AA, Ramharter M, Agnandji ST, Ateba Ngoa U, Issifou S, Yazdanbahksh M, Kremsner PG. Epidemiology of parasitic co-infections during pregnancy in Lambaréné, Gabon. Trop Med Int Health 2010; 15:1204-9. [DOI: 10.1111/j.1365-3156.2010.02598.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|