Exosomes are nano-sized membrane vesicles released from a wide variety of cells, formed in endosomes by inward budding of the endosomal limiting membrane. They have immune stimulatory-, inhibitory-, or tolerance-inducing effects, depending on their cellular origin, which is why they are investigated for use in vaccine and immune therapeutic strategies. In this study, we explored whether exosomes of different origins and functions can selectively target different immune cells in human peripheral blood. Flow cytometry, confocal laser scanning microscopy, and multispectral imaging flow cytometry (ImageStream) revealed that exosomes derived from human monocyte-derived dendritic cells and breast milk preferably associated with monocytes. In contrast, exosomes from an EBV-transformed B cell line (LCL1) preferentially targeted B cells. This was not observed for an EBV− B cell line (BJAB). Electron microscopy, size-distribution analysis (NanoSight), and a cord blood transformation assay excluded the presence of virions in our LCL1 exosome preparations. The interaction between LCL1-derived exosomes and peripheral blood B cells could be blocked efficiently by anti-CD21 or anti-gp350, indicating an interaction between CD21 on B cells and the EBV glycoprotein gp350 on exosomes. The targeting of LCL1-derived exosomes through gp350–CD21 interaction strongly inhibited EBV infection in B cells isolated from umbilical cord blood, suggesting a protective role for exosomes in regulating EBV infection. Our finding also suggests that exosome-based vaccines can be engineered for specific B cell targeting by inducing gp350 expression.

Among the groundbreaking achievements of the International Conference on Population and Development (ICPD) was its call to place adolescent sexual and reproductive health (ASRH) on global health and development agendas. This article reviews progress made in low-and middle-income countries in the 25 years since the ICPD in six areas central to ASRHdadolescent pregnancy, HIV, child marriage, violence against women and girls, female genital mutilation, and menstrual hygiene and health. It also examines the ICPD's contribution to the progress made. The article presents epidemiologic levels and trends; political, research, programmatic and social responses; and factors that helped or hindered progress. To do so, it draws on research evidence and programmatic experience and the expertise and experiences of a wide number of individuals, including youth leaders, in numerous countries and organizations. Overall, looking across the six health topics over a 25-year trajectory, there has been great progress at the global and regional levels in putting adolescent health, and especially adolescent sexual and reproductive health and rights, higher on the agenda, raising investment in this area, building the epidemiologic and evidence-base, and setting norms to guide investment and action. At the national level, too, there has been progress in formulating laws and policies, developing strategies and programs and executing them, and engaging communities and societies in moving the agenda forward. Still, progress has been uneven across issues and geography. Furthermore, it has raced ahead sometimes and has stalled at others. The ICPD's Plan of Action contributed to the progress made in ASRH not just because of its bold call in 1994 but also because it provided a springboard for advocacy, investment, action, and research that remains important to this day.

BackgroundAbortion is restricted in Uganda, and poor access to contraceptive methods result in unwanted pregnancies. This leaves women no other choice than unsafe abortion, thus placing a great burden on the Ugandan health system and making unsafe abortion one of the major contributors to maternal mortality and morbidity in Uganda. The existing sexual and reproductive health policy in Uganda supports the sharing of tasks in post-abortion care. This task sharing is taking place as a pragmatic response to the increased workload. This study aims to explore physicians’ and midwives’ perception of post-abortion care with regard to professional competences, methods, contraceptive counselling and task shifting/sharing in post-abortion care.MethodsIn-depth interviews (n = 27) with health care providers of post-abortion care were conducted in seven health facilities in the Central Region of Uganda. The data were organized using thematic analysis with an inductive approach.ResultsPost-abortion care was perceived as necessary, albeit controversial and sometimes difficult to provide. Together with poor conditions post-abortion care provoked frustration especially among midwives. Task sharing was generally taking place and midwives were identified as the main providers, although they would rarely have the proper training in post-abortion care. Additionally, midwives were sometimes forced to provide services outside their defined task area, due to the absence of doctors. Different uterine evacuation skills were recognized although few providers knew of misoprostol as a method for post-abortion care. An overall need for further training in post-abortion care was identified.ConclusionsTask sharing is taking place, but providers lack the relevant skills for the provision of quality care. For post-abortion care to improve, task sharing needs to be scaled up and in-service training for both doctors and midwives needs to be provided. Post-abortion care should further be included in the educational curricula of nurses and midwives. Scaled-up task sharing in post-abortion care, along with misoprostol use for uterine evacuation would provide a systematic approach to improving the quality of care and accessibility of services, with the aim of reducing abortion-related mortality and morbidity in Uganda.

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