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Background Doxycycline is used for treatment of Mansonella perstans infection. Immune modulatory effects of both M. perstans and doxycycline have been described but long-term implications on host immune response are not defined. Here we determined multiple immune parameters of M. perstans– infected individuals before and after doxycycline treatment to characterize doxycycline effects on host T-cell immunity. Methods Immune characterization of doxycycline-treated M. perstans– infected individuals was performed as part of an open-label randomized clinical trial. Immune cell population phenotyping by flow cytometry and functional in vitro T-cell assays were performed at baseline, 6 months, and "long term" (18–24 months) after treatment start. Treatment efficacy, based on peripheral blood microfilaria (mf) burden, was correlated with immune parameters and effects on immune response against concomitant Mycobacterium tuberculosis infection were determined. Results Immune population phenotyping indicated changes in functional T-cell responses after doxycycline treatment. Constitutive and superantigen-induced T-cell activation and polarization towards T-helper type (TH) 1 phenotype at baseline declined after doxycycline treatment, whereas low proportions of TH17 and TH1* cells at baseline increased significantly at follow-up. In accordance, long-term decline in antigen-specific TH1 responses against concomitant M. tuberculosis infection was seen. Notably, only TH17 and TH1* changes after 6 months and TH17 at baseline were negatively correlated with M. perstans microfilaria burden or reduction, whereas long-term changes were not associated with treatment efficacy. Conclusions We found long-term immune modulatory effects of doxycycline treatment leading to decreased constitutive T-cell activation, polarization towards TH17/TH1*, and impaired immune response against concomitant M. tuberculosis infection. [ABSTRACT FROM AUTHOR]

Background: Malaria continues to be a great public health concern due to the significant mortality and morbidity associated with the disease especially in developing countries. Microparticles (MPs), also called plasma membrane derived extracellular vesicles (PMEVs) are subcellular structures that are generated when they bud off the plasma membrane. They can be found in healthy individuals but the numbers tend to increase in pathological conditions including malaria. Although, various studies have been carried out on the protein content of specific cellular derived MPs, there seems to be paucity of information on the protein content of circulating MPs in malaria and their association with the various signs and symptoms of the disease. The aim of this study was therefore to carry out proteomic analyses of MPs isolated from malaria positive samples and compare them with proteins of MPs from malaria parasite culture supernatant and healthy controls in order to ascertain the role of MPs in malaria infection. Methods: Plasma samples were obtained from forty-three (43) malaria diagnosed patients (cases) and ten (10) healthy individuals (controls). Malaria parasite culture supernatant was obtained from our laboratory and MPs were isolated from them and confirmed using flow cytometry. 2D LC-MS was done to obtain their protein content. Resultant data were analyzed using SPSS Ver. 21.0 statistical software, Kruskal Wallis test and Spearman's correlation coefficient r. Results: In all, 1806 proteins were isolated from the samples. The MPs from malaria positive samples recorded 1729 proteins, those from culture supernatant were 333 while the control samples recorded 234 proteins. The mean number of proteins in MPs of malaria positive samples was significantly higher than that in the control samples. Significantly, higher quantities of haemoglobin subunits were seen in MPs from malaria samples and culture supernatant compared to control samples. Conclusion: A great number of proteins were observed to be carried in the microparticles (MPs) from malaria samples and culture supernatant compared to controls. The greater loss of haemoglobin from erythrocytes via MPs from malaria patients could serve as the initiation and progression of anaemia in P.falciparum infection. Also while some proteins were upregulated in circulating MPs in malaria samples, others were down regulated. [ABSTRACT FROM AUTHOR]

Background: Community Based Surveillance Volunteers (CBSVs) have been instrumental in the management of Neglected Tropical Diseases (NTDs) but a concern that their services in scale up programmes may be affected due to high attrition rates has been widely acknowledged. We explored the roles and capacity needs of existing CBSVs to inform for a successful integrated NTD management programme in Ghana and similar contexts., Methods: We conducted qualitative interviews with 50 CBSVs, 21 Community Nurses, 4 Disease control officers, 7 skin NTD researchers, 2 skin NTD patients and a Director of District Health Services in Central Ghana. Interviews were digitally recorded, transcribed and coded prior to translation and thematic analysis., Results: The roles of CBSVs in NTD management were shown to have an impact on disease identification, surveillance, health seeking behaviours and status of CBSVs. Lack of motivation, inadequate structures for engagement of CBSVs within the health system and delayed management of reported cases were identified as gaps that hinder effective delivery of CBSV roles. Provision of incentives as recognition for the unpaid services rendered by CBSVs was seen as a major factor to reduce the rate of CBSV attrition in this scale up programme. Other factors included the formulation of policies by government to guide CBSV engagement, regular training of CBSV in NTD management as well as provision of resources and logistics., Conclusion: Measures including continuous training, institution of rewards and incentivization are important for ensuring the sustainability of CBSVs in the provision of skin NTD services in Ghana., (© 2023. The Author(s).)