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1.
Brain ; 147(1): 147-162, 2024 01 04.
Article in English | MEDLINE | ID: mdl-37640028

ABSTRACT

Multiple sclerosis is a chronic neuroinflammatory disorder characterized by demyelination, oligodendrocyte damage/loss and neuroaxonal injury in the context of immune cell infiltration in the CNS. No neuroprotective therapy is available to promote the survival of oligodendrocytes and protect their myelin processes in immune-mediated demyelinating diseases. Pro-inflammatory CD4 Th17 cells can interact with oligodendrocytes in multiple sclerosis and its animal model, causing injury to myelinating processes and cell death through direct contact. However, the molecular mechanisms underlying the close contact and subsequent detrimental interaction of Th17 cells with oligodendrocytes remain unclear. In this study we used single cell RNA sequencing, flow cytometry and immunofluorescence studies on CNS tissue from multiple sclerosis subjects, its animal model and controls to characterize the expression of cell adhesion molecules by mature oligodendrocytes. We found that a significant proportion of human and murine mature oligodendrocytes express melanoma cell adhesion molecule (MCAM) and activated leukocyte cell adhesion molecule (ALCAM) in multiple sclerosis, in experimental autoimmune encephalomyelitis and in controls, although their regulation differs between human and mouse. We observed that exposure to pro-inflammatory cytokines or to human activated T cells are associated with a marked downregulation of the expression of MCAM but not of ALCAM at the surface of human primary oligodendrocytes. Furthermore, we used in vitro live imaging, immunofluorescence and flow cytometry to determine the contribution of these molecules to Th17-polarized cell adhesion and cytotoxicity towards human oligodendrocytes. Silencing and blocking ALCAM but not MCAM limited prolonged interactions between human primary oligodendrocytes and Th17-polarized cells, resulting in decreased adhesion of Th17-polarized cells to oligodendrocytes and conferring significant protection of oligodendrocytic processes. In conclusion, we showed that human oligodendrocytes express MCAM and ALCAM, which are differently modulated by inflammation and T cell contact. We found that ALCAM is a ligand for Th17-polarized cells, contributing to their capacity to adhere and induce damage to human oligodendrocytes, and therefore could represent a relevant target for neuroprotection in multiple sclerosis.


Subject(s)
Encephalomyelitis, Autoimmune, Experimental , Multiple Sclerosis , Humans , Mice , Animals , CD4-Positive T-Lymphocytes/metabolism , Activated-Leukocyte Cell Adhesion Molecule/metabolism , Cell Adhesion , Oligodendroglia/metabolism
2.
Virol J ; 20(1): 57, 2023 03 30.
Article in English | MEDLINE | ID: mdl-36997951

ABSTRACT

BACKGROUND: The aim of this study was to evaluate the performance of ten (10) SARS-CoV-2 serological rapid diagnostic tests in comparison with the WANTAI SARS-CoV-2 Ab ELISA test in a laboratory setting. MATERIALS AND METHODS: Ten (10) SARS-CoV-2 serological rapid diagnostic tests (RDTs) for SARS-CoV-2 IgG/IgM were evaluated with two (2) groups of plasma tested positive for one and negative for the other with the WANTAI SARS-CoV-2 Ab ELISA. The diagnostic performance of the SARS-CoV-2 serological RDTs and their agreement with the reference test were calculated with their 95% confidence intervals. RESULTS: The sensitivity of serological RDTs ranged from 27.39 to 61.67% and the specificity from 93.33 to 100% compared to WANTAI SARS-CoV-2 Ab ELISA test. Of all the tests, two tests (STANDARD Q COVID-19 IgM/IgG Combo SD BIOSENSOR and COVID-19 IgG/IgM Rapid Test (Zhejiang Orient Gene Biotech Co., Ltd)) had a sensitivity greater than 50%. In addition, all ten tests had specificity greater than or equal to 93.33% each. The concordance between RDTs and WANTAI SARS-CoV-2 Ab ELISA test ranged from 0.25 to 0.61. CONCLUSION: The SARS-CoV-2 serological RDTs evaluated show low and variable sensitivities compared to the WANTAI SARS-CoV-2 Ab ELISA test, with however a good specificity. These finding may have implications for the interpretation and comparison of COVID-19 seroprevalence studies depending on the type of test used.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , COVID-19/diagnosis , Burkina Faso , Seroepidemiologic Studies , Sensitivity and Specificity , Enzyme-Linked Immunosorbent Assay , Antibodies, Viral , Serologic Tests , Immunoglobulin M/analysis , Immunoglobulin G , COVID-19 Testing
3.
Epilepsy Res ; 192: 107125, 2023 05.
Article in English | MEDLINE | ID: mdl-36963302

ABSTRACT

PURPOSE: Inflammation plays a role in drug-resistant epilepsy (DRE). We have previously reported an increased proportion of CD4 T cells displaying a pro-inflammatory profile in the peripheral blood of adults with DRE. Specific anti-epileptic drugs (AEDs) exhibit immunomodulatory properties that could increase the risk of infections but also contribute to their beneficial impact on DRE and other neurological diseases. The impact of novel generation AEDs on the profile of immune cells and on neuroinflammatory processes remains unclear. METHODS: We compared the influence of brivaracetam and lacosamide on the activation of human and murine peripheral immune cells in vitro and in vivo in active experimental autoimmune encephalomyelitis (EAE), a common mouse model of central nervous system inflammation. RESULTS: We found that brivaracetam and lacosamide at 2.5 µg/ml did not impair the survival and activation of human immune cells, but a higher dose of 25 µg/ml decreased mitogen-induced proliferation of CD8 T cells in vitro. Exposure to high doses of brivaracetam, and to a lesser extent lacosamide, reduced the proportion of CD25+ and CD107a+ CD8+ human T cells in vitro, and the frequency of CNS-infiltrating CD8+ T cells at EAE onset and CD11b+ myeloid cells at peak in vivo. Prophylactic administration of brivaracetam or lacosamide did not delay EAE onset but significantly improved the clinical course in the chronic phase of EAE compared to control. CONCLUSION: Novel generation AEDs do not impair the response to immunization with MOG peptide but improve the course of EAE, possibly through a reduction of neuroaxonal damage.


Subject(s)
Encephalomyelitis, Autoimmune, Experimental , Mice , Humans , Animals , Encephalomyelitis, Autoimmune, Experimental/drug therapy , Encephalomyelitis, Autoimmune, Experimental/prevention & control , Lacosamide/therapeutic use , CD8-Positive T-Lymphocytes , Myelin-Oligodendrocyte Glycoprotein/toxicity , Anti-Inflammatory Agents , Inflammation , Mice, Inbred C57BL
4.
Indian J Med Microbiol ; 42: 59-64, 2023.
Article in English | MEDLINE | ID: mdl-36241531

ABSTRACT

PURPOSE: This study aimed to estimate herpes simplex virus type 2 (HSV-2) seroprevalence and its association with HIV, HBV, HCV, HTLV-1&2 and syphilis among men who have sex with men (MSM) in Ouagadougou, Burkina Faso, West Africa. MATERIALS AND METHODS: We screened MSM sera for HSV-2 antibodies. A total of 329 sera were collected from an HIV and syphilis behavioral and biological cross-sectional survey conducted among MSM in Ouagadougou from January to April 2013. Serum samples were tested using Enzyme Linked Immuno-Sorbent Assay (ELISA) for the detection of IgG antibodies to HSV-2. Also, antibodies to HTLV-1&2, HBsAg and anti-HCV antibodies were screened by ELISA. Laboratory assays were performed according to manufacturers' instructions at the Biomedical Research Laboratory at the "Institut de Recherche en Sciences de la Sante" (IRSS) in Burkina Faso. RESULTS: The seroprevalence of HSV-2 infection among MSM was 14.3%(95% CI: 10.6-18.1), with disparities according to age and occupation. HSV-2 seroprevalence was high among MSM who were seropositive for HIV (40% versus 13.9%), for syphilis (42.9% versus 13.3%), for HCV (32.5% versus 11.7%) and for HTLV-1&2 (38.5% versus 12.9%) compared to people seronegative for these pathogens. Multivariate analysis showed that HIV-positive (ORa â€‹= â€‹5.34, p â€‹= â€‹0.027), anti-HCV-positive (ORa â€‹= â€‹4.44, p â€‹= â€‹0.001), and HTLV-1&2 positive (aOR â€‹= â€‹4.11, p â€‹= â€‹0.046) were associated with HSV-2 infection among MSM. However, no significant statistical association between HSV-2 and syphilis was found. CONCLUSION: HSV-2 seroprevalence among MSM in Burkina Faso is relatively high. Positive associations between sexual transmitted infections including HIV with HSV-2 suggest that HSV-2 infection's prevention should be strengthened through HIV transmission control programs.


Subject(s)
HIV Infections , Herpes Simplex , Human T-lymphotropic virus 1 , Sexual and Gender Minorities , Syphilis , Male , Humans , Syphilis/epidemiology , Herpesvirus 2, Human , Homosexuality, Male , Hepatitis B virus , HIV Infections/complications , HIV Infections/epidemiology , Seroepidemiologic Studies , Burkina Faso/epidemiology , Cross-Sectional Studies , Herpes Simplex/epidemiology , Risk Factors , Prevalence
5.
Infect Drug Resist ; 15: 4517-4527, 2022.
Article in English | MEDLINE | ID: mdl-35992756

ABSTRACT

Seasonal Malaria Chemoprevention (SMC), which combines amodiaquine (AQ) with sulfadoxine-pyrimethamine (SP), is an effective and promising strategy, recommended by WHO, for controlling malaria morbidity and mortality in areas of intense seasonal transmission. Despite the effectiveness of this strategy, a number of controversies regarding the impact of the development of malaria-specific immunity and challenges of the strategy in the context of increasing and expanding antimalarial drugs resistance but also the limited coverage of the SMC in children make the relevance of the SMC questionable, especially in view of the financial and logistical investments. Indeed, the number of malaria cases in the target group, children under 5 years old, has increased while the implementation of SMC is been extended in several African countries. This ambivalence of the SMC strategy, the increase in the prevalence of malaria cases suggests the need to evaluate the SMC and understand some of the factors that may hinder the success of this strategy in the implementation areas. The present review discusses the impact of the SMC on malaria morbidity, parasite resistance to antimalarial drugs, molecular and the immunity affecting the incidence of malaria in children. This approach will contribute to improving the malaria control strategy in highly seasonal transmission areas where the SMC is implemented.

6.
Front Immunol ; 13: 850616, 2022.
Article in English | MEDLINE | ID: mdl-35479072

ABSTRACT

Multiple sclerosis (MS) is characterized by the loss of myelin and of myelin-producing oligodendrocytes (OLs) in the central nervous system (CNS). Pro-inflammatory CD4+ Th17 cells are considered pathogenic in MS and are harmful to OLs. We investigated the mechanisms driving human CD4+ T cell-mediated OL cell death. Using fluorescent and brightfield in vitro live imaging, we found that compared to Th2-polarized cells, Th17-polarized cells show greater interactions with primary human OLs and human oligodendrocytic cell line MO3.13, displaying longer duration of contact, lower mean speed, and higher rate of vesicle-like structure formation at the sites of contact. Using single-cell RNA sequencing, we assessed the transcriptomic profile of primary human OLs and Th17-polarized cells in direct contact or separated by an insert. We showed that upon close interaction, OLs upregulate the expression of mRNA coding for chemokines and antioxidant/anti-apoptotic molecules, while Th17-polarized cells upregulate the expression of mRNA coding for chemokines and pro-inflammatory cytokines such as IL-17A, IFN-γ, and granzyme B. We found that secretion of CCL3, CXCL10, IFN-γ, TNFα, and granzyme B is induced upon direct contact in cocultures of human Th17-polarized cells with human OLs. In addition, we validated by flow cytometry and immunofluorescence that granzyme B levels are upregulated in Th17-polarized compared to Th2-polarized cells and are even higher in Th17-polarized cells upon direct contact with OLs or MO3.13 cells compared to Th17-polarized cells separated from OLs by an insert. Moreover, granzyme B is detected in OLs and MO3.13 cells following direct contact with Th17-polarized cells, suggesting the release of granzyme B from Th17-polarized cells into OLs/MO3.13 cells. To confirm granzyme B-mediated cytotoxicity toward OLs, we showed that recombinant human granzyme B can induce OLs and MO3.13 cell death. Furthermore, pretreatment of Th17-polarized cells with a reversible granzyme B blocker (Ac-IEPD-CHO) or a natural granzyme B blocker (serpina3N) improved survival of MO3.13 cells upon coculture with Th17 cells. In conclusion, we showed that human Th17-polarized cells form biologically significant contacts with human OLs and exert direct toxicity by releasing granzyme B.


Subject(s)
Multiple Sclerosis , Th17 Cells , Granzymes/metabolism , Humans , Interferon-gamma/metabolism , Multiple Sclerosis/metabolism , Oligodendroglia , RNA, Messenger/metabolism , Th17 Cells/metabolism
7.
Rev. int. sci. méd. (Abidj.) ; 24(1): 85-92, 2022. figures, tables
Article in French | AIM (Africa) | ID: biblio-1396938

ABSTRACT

Contexte/objectif : La maladie à coronavirus (COVID-19) est une maladie émergente, dont l'agentpathogène est le virus du syndrome respiratoire aigu sévère dû au coronavirus 2 (SRAS-CoV-2). L'objectif de cette étudeétait de décrire le profil virologique et clinique des patients diagnostiqués dans deux laboratoires. Matériels et méthodes : Il s'est agi d'uneétude descriptive avec collecte rétrospective de données des patients atteints de COVID-19, qui a couvert la période du 04 avril au 31 décembre 2020. Le test de khi deux et le test exact de Fisher sont les tests statistiques utilisées. Résultats : Au total, 28 872 échantillons ont été testés dans les deux laboratoires. L'étude arévélé 1965 cas positifs soit 6, 80% (63 % hommes et 37,05 % femmes). La tranche d'âge de 20 à 50 ans représentait 68,68 %. La province de la capitale a enregistré autant le plus grand nombre d'échantillons (26277 soit91,00%) que le plus grand nombre des cas positifs (91,15%). Les manifestations cliniques étaient dominées par la toux 68,42%, la fatigue générale (43,86%), les céphalées (43,86%), l'écoulement nasal (40,93%), la fi èvre (39,18%). Les comorbidités les plus fréquentes étaient l'hypertension artérielle (HTA) et le diabète. Conclusion: Cette étude a montré unepopulation jeune testée. La capitale (Ouagadougou) a enregistré le plus grand nombre de demandeurs de tests et de cas positifs. La toux était la principale manifestation clinique. Les patients avec comorbidités dont l'HTA et le diabète ont été les plus nombreux a effectué le test


Background/Purpose. Coronavirus disease (COVID-19) is an emerging disease, whose pathogen is the severe acute respiratory syndrome virus due to coronavirus 2 (SARS-CoV-2). The objective of this study was to describe the virological and clinical profile of patients diagnosed in two laboratories. Methods. This was a descriptive study with retrospective data collection of patients with COVID-19, which covered the period from 04 April to 31 December 2020. Chisquare test and Fisher's exact test were used as statistical tests. Results. A total of 28,872 samples were tested in the two laboratories. The study revealed 1965 positive cases or 6, 80% (63% male and 37.05% female). The age group 20-50 years represented 68.68%. The capital province recorded both the largest number of samples (26277 or 91.00%) and the largest number of positive cases (91.15%). Clinical manifestations were dominated by cough 68.42%, general fatigue (43.86%), headache (43.86%), nasal discharge (40.93%), fever (39.18%). The most frequent comorbidities were arterial hypertension (AH) and diabetes. Conclusion. This study showed a young population tested. The capital (Ouagadougou) recorded the highest number of testers and positive cases. Cough was the main clinical manifestation. Patients with comorbidities including hypertension and diabetes were the most numerous to be tested


Subject(s)
Virology , Diagnosis , COVID-19 , Laboratories, Clinical
8.
Epilepsia ; 62(1): 176-189, 2021 01.
Article in English | MEDLINE | ID: mdl-33140401

ABSTRACT

OBJECTIVE: Adult drug-resistant epilepsy (DRE) is associated with significant morbidity. Infiltration of immune cells is observed in DRE epileptic foci; however, the relation between DRE and the peripheral immune cell compartment remains only partially understood. We aimed to investigate differences in immune cell populations, cytokines, and neurodegenerative biomarkers in the peripheral blood of subjects with epilepsy versus healthy controls, and in DRE compared to well-controlled epilepsy (WCE). METHODS: Peripheral blood mononuclear cells and serum from >120 age- and sex-matched adults suffering from focal onset epilepsy and controls were analyzed by multipanel flow cytometry, multiplex immunoassays, and ultrasensitive single molecule array. RESULTS: Using a data-driven analytical approach, we identified that CD4 T cells in the peripheral blood are present in a higher proportion in DRE patients. Moreover, we observed that the frequency of CD4 T cells expressing proinflammatory cytokines interleukin (IL)-17A, IL-22, tumor necrosis factor, interferon-γ, and granulocyte-macrophage colony-stimulating factor, but not anti-inflammatory cytokines IL-10 and IL-4, is elevated in the peripheral blood of DRE subjects compared to WCE. In parallel, we found that Th17-related circulating proinflammatory cytokines are elevated, but Th2-related cytokine IL-4 is reduced, in the serum of epilepsy and DRE subjects. As Th17 cells can exert neurotoxicity, we measured levels of serum neurofilament light chain (sNfL), a marker of neuronal injury. We found significantly elevated levels of sNfL in DRE compared to controls, especially among older individuals. SIGNIFICANCE: Our data support that DRE is associated with an expansion of the CD4 Tcell subset in the peripheral blood and with a shift toward a proinflammatory Th17/Th1 CD4 Tcell immune profile. Our results further show that pathological levels of sNfL are more frequent in DRE, supporting a potential neurodegenerative component in adult DRE. With this work, we provide evidence for novel potential inflammatory and degenerative biomarkers in DRE.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Cytokines/immunology , Drug Resistant Epilepsy/immunology , Neurofilament Proteins/immunology , Adult , CD4 Lymphocyte Count , Case-Control Studies , Epilepsy/drug therapy , Epilepsy/immunology , Female , Flow Cytometry , Granulocyte-Macrophage Colony-Stimulating Factor/immunology , Humans , Immunoassay , Inflammation , Interferon-gamma/immunology , Interleukin-10/immunology , Interleukin-17/immunology , Interleukin-4/immunology , Interleukins/immunology , Male , Middle Aged , Single Molecule Imaging , Th17 Cells/immunology , Th2 Cells/immunology , Tumor Necrosis Factor-alpha/immunology , Young Adult , Interleukin-22
10.
Heliyon ; 6(8): e04581, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32793827

ABSTRACT

Balanites aegyptiaca (L.) Delile is native to semi-arid regions in Africa where it is a well-known and conspicuous component of savannas. The species is highly preferred by local people because of its high socio-economic, cultural and ecological values. However, the species faces multiple environmental challenges such as desertification and human pressure. This study aimed to develop allometric models to predict aboveground biomass (AGB) of B. aegyptiaca in two climatic zones in Burkina Faso. Overall, thirty trees were sampled using destructive method in six study stands along two climatic zones. We assessed the biomass allocation to the different components of trees by computing its fraction. Furthermore, allometric models based on diameter at breast height (dbh) and basal diameter at 20 cm height (D20) were fitted separately as well as combined with crown diameter (CD) and/or tree total height (Ht). For each biomass component, non-linear allometric models were fitted. Branch biomass accounted for 64% of the AGB in the two climatic zones and increased with dbh. No significant difference in carbon content was found. However, biomass allotment (except leaves) varied across climatic zones. Although both dbh and D20 are typically used as independent variables for predicting AGB, the inclusion of the height in the equations did not significantly improve the statistical fits for B. aegyptica. However, adding CD to dbh improved significantly the equations only in the Sudano-Sahelian zone. The established allometric models can provide reliable and accurate estimation of individual tree biomass of the species in areas of similar conditions and may contribute to relevant ecological and economical biomass inventories.

11.
Int J Immunogenet ; 46(1): 1-6, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30447055

ABSTRACT

Geographical distribution of ABO and RHD antigens is important for blood transfusion services and population genetics studies. There are few data on this topic in Burkina Faso, a multi-ethnic country. Our study aims at reporting phenotypic and allelic frequencies of ABO and RHD blood groups among voluntary blood donors from various ethnical regions of Burkina Faso. We conducted a cross-sectional study including 81,486 blood donors. ABO allelic frequencies were determined using the Bernstein method. Differences in phenotypic distribution of blood groups were assessed using the chi-square test; a p value <0.05 being considered as statistically significant. We noticed that O+>B+>A+>AB+>O->B->A->AB- in our population. Phenotypic frequencies of blood groups A, B, O and AB were respectively 22.54%, 28.56%, 43.30% and 5.60%. RHD+was 92.24%. The allelic frequencies of A, B, O and D were respectively 0.1524; 0.1887; 0.6590 and 0.7214. We noticed statistical differences (p < 0.05) between these administrative regions which corresponded roughly to some natural ethnic areas. Indeed, the phenotype O was more frequent in the Central-west, Central and East regions corresponding to "Mossi," "Gourounsi," "Gourmantché" areas while the phenotype A and AB were more reported in "Boucle du mouhoun" and "Hauts-Bassins" regions where we have "Bwaba" and "Bobo." The phenotype O negative was less frequent in "Bwaba." Our study provides interesting information to blood services that will allow them to better refine their donor recruitment strategies.


Subject(s)
ABO Blood-Group System/genetics , Antigens/genetics , Rh-Hr Blood-Group System/genetics , ABO Blood-Group System/immunology , Adult , Antigens/blood , Antigens/immunology , Blood Donors , Burkina Faso , Ethnicity/genetics , Female , Gene Frequency/genetics , Humans , Male , Rh-Hr Blood-Group System/immunology
12.
BMC Res Notes ; 10(1): 472, 2017 Sep 08.
Article in English | MEDLINE | ID: mdl-28886727

ABSTRACT

BACKGROUND: High parasite-specific antibody levels are generally associated with low susceptibility to Plasmodium falciparum malaria. This has been supported by several studies in which clinical malaria cases of P. falciparum malaria were reported to be associated with low antibody avidities. This study was conducted to evaluate the role of age, malaria transmission intensity and incidence of clinical malaria in the induction of protective humoral immune response against P. falciparum malaria in children living in Burkina Faso. METHODS: We combined levels of IgG and IgG subclasses responses to P. falciparum antigens: Merozoite Surface Protein 3 (MSP3), Merozoite Surface Protein 2a (MSP2a), Merozoite Surface Protein 2b (MSP2b), Glutamate Rich Protein R0 (GLURP R0) and Glutamate Rich Protein R2 (GLURP R2) in plasma samples from 325 children under five (05) years with age, malaria transmission season and malaria incidence. RESULTS: We notice higher prevalence of P. falciparum infection in low transmission season compared to high malaria transmission season. While, parasite density was lower in low transmission than high transmission season. IgG against all antigens investigated increased with age. High levels of IgG and IgG subclasses to all tested antigens except for GLURP R2 were associated with the intensity of malaria transmission. IgG to MSP3, MSP2b, GLURP R2 and GLURP R0 were associated with low incidence of malaria. All IgG subclasses were associated with low incidence of P. falciparum malaria, but these associations were stronger for cytophilic IgGs. CONCLUSIONS: On the basis of the data presented in this study, we conclude that the induction of humoral immune response to tested malaria antigens is related to age, transmission season level and incidence of clinical malaria.


Subject(s)
Antibodies, Protozoan/blood , Antibody Formation/immunology , Antigens, Protozoan/immunology , Malaria, Falciparum/blood , Malaria, Falciparum/epidemiology , Plasmodium falciparum/immunology , Adolescent , Age Factors , Burkina Faso/epidemiology , Child , Child, Preschool , Female , Humans , Incidence , Infant , Male
13.
PLoS One ; 12(9): e0184457, 2017.
Article in English | MEDLINE | ID: mdl-28880962

ABSTRACT

Over the last decades agroforestry parklands in Burkina Faso have come under increasing demographic as well as climatic pressures, which are threatening indigenous tree species that contribute substantially to income generation and nutrition in rural households. Analyzing the threats as well as the species vulnerability to them is fundamental for priority setting in conservation planning. Guided by literature and local experts we selected 16 important food tree species (Acacia macrostachya, Acacia senegal, Adansonia digitata, Annona senegalensis, Balanites aegyptiaca, Bombax costatum, Boscia senegalensis, Detarium microcarpum, Lannea microcarpa, Parkia biglobosa, Sclerocarya birrea, Strychnos spinosa, Tamarindus indica, Vitellaria paradoxa, Ximenia americana, Ziziphus mauritiana) and six key threats to them (overexploitation, overgrazing, fire, cotton production, mining and climate change). We developed a species-specific and spatially explicit approach combining freely accessible datasets, species distribution models (SDMs), climate models and expert survey results to predict, at fine scale, where these threats are likely to have the greatest impact. We find that all species face serious threats throughout much of their distribution in Burkina Faso and that climate change is predicted to be the most prevalent threat in the long term, whereas overexploitation and cotton production are the most important short-term threats. Tree populations growing in areas designated as 'highly threatened' due to climate change should be used as seed sources for ex situ conservation and planting in areas where future climate is predicting suitable habitats. Assisted regeneration is suggested for populations in areas where suitable habitat under future climate conditions coincides with high threat levels due to short-term threats. In the case of Vitellaria paradoxa, we suggest collecting seed along the northern margins of its distribution and considering assisted regeneration in the central part where the current threat level is high due to overexploitation. In the same way, population-specific recommendations can be derived from the individual and combined threat maps of the other 15 food tree species. The approach can be easily transferred to other countries and can be used to analyze general and species specific threats at finer and more local as well as at broader (continental) scales in order to plan more selective and efficient conservation actions in time. The concept can be applied anywhere as long as appropriate spatial data are available as well as knowledgeable experts.


Subject(s)
Conservation of Natural Resources/methods , Food , Acacia , Adansonia , Anacardiaceae , Annona , Balanites , Bombax , Burkina Faso , Climate Change , Ecosystem , Olacaceae , Tamarindus
14.
Mol Ther ; 25(2): 547-559, 2017 02 01.
Article in English | MEDLINE | ID: mdl-28153101

ABSTRACT

Heterologous prime-boosting with viral vectors encoding the pre-erythrocytic antigen thrombospondin-related adhesion protein fused to a multiple epitope string (ME-TRAP) induces CD8+ T cell-mediated immunity to malaria sporozoite challenge in European malaria-naive and Kenyan semi-immune adults. This approach has yet to be evaluated in children and infants. We assessed this vaccine strategy among 138 Gambian and Burkinabe children in four cohorts: 2- to 6-year olds in The Gambia, 5- to 17-month-olds in Burkina Faso, and 5- to 12-month-olds and 10-week-olds in The Gambia. We assessed induction of cellular immunity, taking into account the distinctive hematological status of young infants, and characterized the antibody response to vaccination. T cell responses peaked 7 days after boosting with modified vaccinia virus Ankara (MVA), with highest responses in infants aged 10 weeks at priming. Incorporating lymphocyte count into the calculation of T cell responses facilitated a more physiologically relevant comparison of cellular immunity across different age groups. Both CD8+ and CD4+ T cells secreted cytokines. Induced antibodies were up to 20-fold higher in all groups compared with Gambian and United Kingdom (UK) adults, with comparable or higher avidity. This immunization regimen elicited strong immune responses, particularly in young infants, supporting future evaluation of efficacy in this key target age group for a malaria vaccine.


Subject(s)
Antibodies, Protozoan/immunology , Genetic Vectors , Malaria Vaccines/immunology , Malaria, Falciparum/immunology , Malaria, Falciparum/prevention & control , Plasmodium falciparum/immunology , T-Lymphocytes/immunology , Africa, Western , Antibodies, Protozoan/blood , Child , Child, Preschool , Enzyme-Linked Immunosorbent Assay , Female , Flow Cytometry , Genetic Vectors/adverse effects , Genetic Vectors/genetics , Genetic Vectors/immunology , Humans , Immunity, Cellular , Immunity, Humoral , Immunoglobulin Isotypes/blood , Immunoglobulin Isotypes/immunology , Infant , Infant, Newborn , Malaria Vaccines/administration & dosage , Malaria Vaccines/genetics , T-Lymphocytes/metabolism , Vaccination
15.
Mol Ther ; 24(8): 1470-7, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27109630

ABSTRACT

Malaria remains a significant global health burden and a vaccine would make a substantial contribution to malaria control. Chimpanzee Adenovirus 63 Modified Vaccinia Ankara Multiple epitope thrombospondin adhesion protein (ME-TRAP) and vaccination has shown significant efficacy against malaria sporozoite challenge in malaria-naive European volunteers and against malaria infection in Kenyan adults. Infants are the target age group for malaria vaccination; however, no studies have yet assessed T-cell responses in children and infants. We enrolled 138 Gambian and Burkinabe children in four different age-groups: 2-6 years old in The Gambia; 5-17 months old in Burkina Faso; 5-12 months old, and also 10 weeks old, in The Gambia; and evaluated the safety and immunogenicity of Chimpanzee Adenovirus 63 Modified Vaccinia Ankara ME-TRAP heterologous prime-boost immunization. The vaccines were well tolerated in all age groups with no vaccine-related serious adverse events. T-cell responses to vaccination peaked 7 days after boosting with Modified Vaccinia Ankara, with T-cell responses highest in 10 week-old infants. Heterologous prime-boost immunization with Chimpanzee Adenovirus 63 and Modified Vaccinia Ankara ME-TRAP was well tolerated in infants and children, inducing strong T-cell responses. We identify an approach that induces potent T-cell responses in infants, which may be useful for preventing other infectious diseases requiring cellular immunity.


Subject(s)
Adenoviruses, Simian , Epitopes , Genetic Vectors , Malaria Vaccines/immunology , Malaria/prevention & control , Vaccinia virus , Africa, Western/epidemiology , Animals , Antibodies, Protozoan/blood , Antibodies, Protozoan/immunology , Child , Child, Preschool , Enzyme-Linked Immunospot Assay , Epitopes/immunology , Gambia , Genetic Vectors/adverse effects , Humans , Immunization, Secondary , Infant , Infant, Newborn , Malaria/epidemiology , Malaria Vaccines/administration & dosage , Malaria Vaccines/adverse effects , Outcome Assessment, Health Care
16.
J Ethnobiol Ethnomed ; 11: 9, 2015 Feb 19.
Article in English | MEDLINE | ID: mdl-25971673

ABSTRACT

BACKGROUND: The West African country of Burkina Faso (BFA) is an example for the enduring importance of traditional plant use today. A large proportion of its 17 million inhabitants lives in rural communities and strongly depends on local plant products for their livelihood. However, literature on traditional plant use is still scarce and a comprehensive analysis for the country is still missing. METHODS: In this study we combine the information of a recently published plant checklist with information from ethnobotanical literature for a comprehensive, national scale analysis of plant use in Burkina Faso. We quantify the application of plant species in 10 different use categories, evaluate plant use on a plant family level and use the relative importance index to rank all species in the country according to their usefulness. We focus on traditional medicine and quantify the use of plants as remedy against 22 classes of health disorders, evaluate plant use in traditional medicine on the level of plant families and rank all species used in traditional medicine according to their respective usefulness. RESULTS: A total of 1033 species (50%) in Burkina Faso had a documented use. Traditional medicine, human nutrition and animal fodder were the most important use categories. The 12 most common plant families in BFA differed considerably in their usefulness and application. Fabaceae, Poaceae and Malvaceae were the plant families with the most used species. In this study Khaya senegalensis, Adansonia digitata and Diospyros mespiliformis were ranked the top useful plants in BFA. Infections/Infestations, digestive system disorders and genitourinary disorders are the health problems most commonly addressed with medicinal plants. Fabaceae, Poaceae, Asteraceae, Apocynaceae, Malvaceae and Rubiaceae were the most important plant families in traditional medicine. Tamarindus indica, Vitellaria paradoxa and Adansonia digitata were ranked the most important medicinal plants. CONCLUSIONS: The national-scale analysis revealed systematic patterns of traditional plant use throughout BFA. These results are of interest for applied research, as a detailed knowledge of traditional plant use can a) help to communicate conservation needs and b) facilitate future research on drug screening.


Subject(s)
Medicine, African Traditional/statistics & numerical data , Plants, Medicinal , Burkina Faso/epidemiology , Conservation of Natural Resources , Humans , Medicine, African Traditional/methods , Phytotherapy/methods , Phytotherapy/statistics & numerical data
18.
PLoS One ; 9(9): e107965, 2014.
Article in English | MEDLINE | ID: mdl-25238160

ABSTRACT

BACKGROUND: Children below six months are reported to be less susceptible to clinical malaria. Maternally derived antibodies and foetal haemoglobin are important putative protective factors. We examined antibodies to Plasmodium falciparum merozoite surface protein 3 (MSP3) and glutamate-rich protein (GLURP), in children in their first two years of life in Burkina Faso and their risk of malaria. METHODS: A cohort of 140 infants aged between four and six weeks was recruited in a stable transmission area of south-western Burkina Faso and monitored for 24 months by active and passive surveillance. Malaria infections were detected by examining blood smears using light microscopy. Enzyme-linked immunosorbent assay was used to quantify total Immunoglobulin G to Plasmodium falciparum antigens MSP3 and two regions of GLURP (R0 and R2) on blood samples collected at baseline, three, six, nine, 12, 18 and 24 months. Foetal haemoglobin and variant haemoglobin fractions were measured at the baseline visit using high pressure liquid chromatography. RESULTS: A total of 79.6% of children experienced one or more episodes of febrile malaria during monitoring. Antibody titres to MSP3 were prospectively associated with an increased risk of malaria while antibody responses to GLURP (R0 and R2) did not alter the risk. Antibody titres to MSP3 were higher among children in areas of high malaria risk. Foetal haemoglobin was associated with delayed first episode of febrile malaria and haemoglobin CC type was associated with reduced incidence of febrile malaria. CONCLUSIONS: We did not find any evidence of association between titres of antibodies to MSP3, GLURP-R0 or GLURP-R2 as measured by enzyme-linked immunosorbent assay and early protection against malaria, although anti-MSP3 antibody titres may reflect increased exposure to malaria and therefore greater risk. Foetal haemoglobin was associated with protection against febrile malaria despite the study limitations and its role is therefore worthy further investigation.


Subject(s)
Antigens, Protozoan/immunology , Fetal Hemoglobin/immunology , Malaria Vaccines/immunology , Malaria, Falciparum/immunology , Protozoan Proteins/immunology , Burkina Faso , Child, Preschool , Enzyme-Linked Immunosorbent Assay , Female , Humans , Incidence , Infant , Infant, Newborn , Longitudinal Studies , Malaria, Falciparum/epidemiology , Male , Maternal-Fetal Exchange/immunology , Plasmodium falciparum/immunology , Plasmodium falciparum/pathogenicity , Pregnancy , Risk Assessment
19.
Pan Afr Med J ; 19: 396, 2014.
Article in English | MEDLINE | ID: mdl-25995792

ABSTRACT

INTRODUCTION: For a high quality level diagnosis, mycobacterium culture must comply with the pre-analytical and analytical conditions recommended by the WHO and the country National Tuberculosis Program (NTP). In this study, we determined whether temperature and duration of sputum storage were associated with culture contamination in Burkina Faso. METHODS: Sputa were collected in 5 districts labs in Burkina Faso. Temperature and duration of sputum storage were recorded. After the collection, sputa were decontaminated using Petroff modified method, and the pellet was inoculated on LJ media and LJ media supply with 2% sodium pyruvate. Risk of culture contamination associated with temperature and duration of sputum storage was measured by Chi2 test and logistic regression. RESULTS: Out of 404 specimens, 61% (246/404) were stored between 2 and 8°C, and 15% (61/404) were processed within three days. The global contamination rate was 24%, with only 8% for samples respecting WHO recommendations, up to 35% for others. Storage at room temperature was associated with a significantly higher risk of contamination compared to storage at 2-8°C (OR 2.24, p = 0.001, IC 95%). CONCLUSION: The recommendations about the temperature and the duration of sputum storage before cultures are not completely respected. This leads to high contamination rate of mycobacterium culture. It will be necessary to take logistics measures in peripherals health services or to develop more selective medium for mycobacterium culture in low income countries.


Subject(s)
Equipment Contamination/statistics & numerical data , Mycobacterium/growth & development , Specimen Handling/statistics & numerical data , Sputum/microbiology , Tuberculosis/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Burkina Faso/epidemiology , Female , Humans , Male , Microbiological Techniques/standards , Microbiological Techniques/statistics & numerical data , Middle Aged , Mycobacterium/isolation & purification , Specimen Handling/standards , Tuberculosis/epidemiology , Tuberculosis/microbiology , Tuberculosis/pathology , Young Adult
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