Antibody responses against bacterial glycans affinity mature and diversify in germinal centers.

Anti-carbohydrate antibodies (Abs) play crucial roles in pathogen control, but their generation remains poorly understood. By studying responses to in humans, we reveal that the glycan-targeted response shifts from IgM towards IgG and IgA memory with age and antigen exposure across blood, spleen, and tonsils. Both natural colonization and controlled human infection with increased class-switched B cells, with evidence of within-clone switching.

Syndecans and glycosaminoglycans influence B-cell development and activation.

Syndecans (SDCs) are glycosaminoglycan-containing cell surface proteins with diverse functions in the immune system with SDC1 (CD138) and SDC4 expressed in B-lineage cells. Here, we show that stem cells lacking either molecule generate fewer B-cell progenitors but give rise to mature B cells in vivo. Deletion of the plasma cell "marker" CD138 has no effect on homeostatic or antigen-induced plasma cell formation.

Understanding experiences of neglected tropical diseases of the skin: a mixed-methods study to inform intervention development in Ethiopia.

Background: The WHO and Ethiopia's Ministry of Health have developed strategies to expand and integrate services for co-endemic neglected tropical diseases (NTDs) which manifest in the skin. To inform these strategies, we aimed to understand the social, economic and health system context of skin NTD care in Kalu woreda, Amhara region, Ethiopia, where cutaneous leishmaniasis (CL) and leprosy are endemic.

Methods: Between October 2020 and May 2022, we surveyed and reviewed records of 41 primary healthcare facilities and explored common disease experiences in focus group discussions (n=40) and interviews with people affected by leprosy (n=37) and CL (n=33), health workers (n=23), kebele authorities and opinion leaders (n=33) and traditional healers (n=7).

Who pays to treat malaria and how much? Analysis of the cost of illness, equity and economic burden of malaria in Uganda.

Case management of malaria in Africa has evolved markedly over the past 20 years and updated cost estimates are needed to guide malaria control policies. We estimated the cost of malaria illness to households and the public health service and assessed the equity of these costs in Uganda. From December 2021 to May 2022, we conducted a costing exercise in eight government-run health centres covering seven sub-regions, collecting health service costs from patient observations, records review and a time-and-motion study.

Conversion of vaccines from low to high immunogenicity by antibodies with epitope complementarity.

Existing antibodies (Abs) have varied effects on humoral immunity during subsequent infections. Here, we leveraged in vivo systems that allow precise control of antigen-specific Abs and B cells to examine the impact of Ab dose, affinity, and specificity in directing B cell activation and differentiation. Abs competing with the B cell receptor (BCR) epitope showed affinity-dependent suppression.

Improving experiences of neglected tropical diseases of the skin: Mixed methods formative research for development of a complex intervention in Atwima Mponua District, Ghana.

Integrated approaches to managing co-endemic neglected tropical diseases (NTDs) of the skin within primary healthcare services are complex and require tailoring to local contexts. We describe formative research in Atwima Mponua District in Ghana's Ashanti Region designed to inform the development of a sustainable intervention to improve access to skin NTD care. We employed a convergent, parallel, mixed-methods design, collecting data from February 2021 to February 2022.

Ki67 deficiency impedes chromatin accessibility and BCR gene rearrangement.

The proliferation marker Ki67 has been attributed critical functions in maintaining mitotic chromosome morphology and heterochromatin organization during the cell cycle, indicating a potential role in developmental processes requiring rigid cell-cycle control. Here, we discovered that despite normal fecundity and organogenesis, germline deficiency in Ki67 resulted in substantial defects specifically in peripheral B and T lymphocytes. This was not due to impaired cell proliferation but rather to early lymphopoiesis at specific stages where antigen-receptor gene rearrangements occurred.

Effectiveness of kangaroo mother care before clinical stabilisation versus standard care among neonates at five hospitals in Uganda (OMWaNA): a parallel-group, individually randomised controlled trial and economic evaluation.

Background: Preterm birth is the leading cause of death in children younger than 5 years worldwide. WHO recommends kangaroo mother care (KMC); however, its effects on mortality in sub-Saharan Africa and its relative costs remain unclear. We aimed to compare the effectiveness, safety, costs, and cost-effectiveness of KMC initiated before clinical stabilisation versus standard care in neonates weighing up to 2000 g.

Did aid to the Ebola crisis divert aid for reproductive, maternal, and newborn health? An analysis of donor-reported data in Sierra Leone.

Background: Infectious disease outbreaks like Ebola and Covid-19 are increasing in frequency. They may harm reproductive, maternal and newborn health (RMNH) directly and indirectly. Sierra Leone experienced a sharp deterioration of RMNH during the 2014-16 Ebola epidemic.

Why cost-effectiveness thresholds for global health donors should differ from thresholds for Ministries of Health (and why it matters).

Healthcare cost-effectiveness analysis is increasingly used to inform priority-setting in low- and middle-income countries and by global health donors. As part of such analyses, cost-effectiveness thresholds are commonly used to determine what is, or is not, cost-effective. Recent years have seen a shift in best practice from a rule-of-thumb 1x or 3x per capita GDP threshold towards using thresholds that, in theory, reflect the opportunity cost of new investments within a given country.

Development of an integrated and decentralised skin health strategy to improve experiences of skin neglected tropical diseases and other skin conditions in Atwima Mponua District, Ghana.

Integrated strategies are recommended to tackle neglected tropical diseases of the skin (skin NTDs), which pose a substantial health and economic burden in many countries, including Ghana. We describe the development of an integrated and decentralised skin health strategy designed to improve experiences of skin NTDs in Atwima Mponua district in Ashanti Region. A multidisciplinary research team led an iterative process to develop an overall strategy and specific interventions, based on a theory of change informed by formative research conducted in Atwima Mponua district.

Assessing equity and efficiency of health financing towards universal health coverage between regions in Tanzania.

Equity and efficiency in health financing are intermediate universal health coverage (UHC) objectives. While there is growing attention to monitoring these goals at the national level, subnational assessment is also needed to uncover potential divergences across subnational units. We assessed whether health funds were allocated or contributed equitably and spent efficiently across 26 regions in Tanzania in 2017/18 for four sources of funding.

Donor aid mentioning newborns and stillbirths, 2002-19: an analysis of levels, trends, and equity.

Background: Global aid for reproductive, maternal, newborn, and child health has stagnated in recent years, and aid mentioning newborns or stillbirths has previously represented a very small proportion of aid for reproductive, maternal, newborn, and child health. Neonatal survival targets have been set by 78 countries, and stillbirth prevention targets have been set by 30 countries, to address the 4·4 million newborn deaths and stillbirths globally. We aimed to generate novel estimates of current levels of, and trends in, aid mentioning newborns and stillbirths over 2002-19, and to assess whether the amount of aid disbursed aligns with the associated mortality burden.

Protocol for a prospective observational cohort study of cutaneous leishmaniasis in Ethiopia.

Background: Cutaneous leishmaniasis (CL) is a skin neglected tropical disease, with an estimated 40,000 new cases each year in Ethiopia. CL causes ulcers, nodules, and plaques on the skin, and in some instances the destruction of the nasopharyngeal mucosa and cartilage. Some CL lesions may heal spontaneously, whilst other lesions may require therapies which are associated with discomfort, adverse effects, prolonged treatment, and a frequent lack of a complete response.

Process and costs for readiness to safely implement immediate kangaroo mother care: a mixed methods evaluation from the OMWaNA trial at five hospitals in Uganda.

Background: Preterm birth complications result in > 1 million child deaths annually, mostly in low- and middle-income countries. A World Health Organisation (WHO)-led trial in hospitals with intensive care reported reduced mortality within 28 days among newborns weighing 1000-1799 g who received immediate kangaroo mother care (iKMC) compared to those who received standard care. Evidence is needed regarding the process and costs of implementing iKMC, particularly in non-intensive care settings.

Intrinsically determined turnover underlies broad heterogeneity in plasma-cell lifespan.

Antibodies produced by antibody-secreting plasma cells (ASCs) underlie multiple forms of long-lasting immunity. Here we examined the mechanisms regulating ASC turnover and persistence using a genetic reporter to time-stamp ASCs. This approach revealed ASC lifespans as heterogeneous and falling on a continuum, with only a small fraction surviving for >60 days.

Buruli-RifDACC: Evaluation of the efficacy and cost-effectiveness of high-dose versus standard-dose rifampicin on outcomes in disease, a protocol for a randomised controlled trial in Ghana.

Background: Buruli ulcer (BU) can lead to disfiguring ulcers and permanent disability. The 2030 World Health Organization (WHO) road map for Neglected Tropical Diseases (NTDs) calls for major scaling up in diagnosis and management to eliminate disability due to the disease. Current treatment for BU is with daily oral rifampicin (10mg/kg dose) and clarithromycin (15mg/kg dose) for eight weeks, combined with standard gauze wound dressings.

Long-lived plasma cells accumulate in the bone marrow at a constant rate from early in an immune response.

Vaccines work largely by generating long-lived plasma cells (LLPCs), but knowledge of how such cells are recruited is sparse. Although it is clear that LLPCs preferentially originate in germinal centers (GCs) and relocate to survival niches in bone marrow where they can persist for decades, the issues of the timing of LLPC recruitment and the basis of their retention remain uncertain. Here, using a genetic timestamping system in mice, we show that persistent PCs accrue in bone marrow at an approximately constant rate of one cell per hour over a period spanning several weeks after a single immunization with a model antigen.

Interleukin-21, acting beyond the immunological synapse, independently controls T follicular helper and germinal center B cells.

Germinal centers (GCs), transient structures within B cell follicles and central to affinity maturation, require the coordinated behavior of T and B cells. IL-21, a pleiotropic T cell-derived cytokine, is key to GC biology through incompletely understood mechanisms. By genetically restricting production and receipt of IL-21 in vivo, we reveal how its independent actions on T and B cells combine to regulate the GC.

Loss of TIP60 (KAT5) abolishes H2AZ lysine 7 acetylation and causes p53, INK4A, and ARF-independent cell cycle arrest.

Histone acetylation is essential for initiating and maintaining a permissive chromatin conformation and gene transcription. Dysregulation of histone acetylation can contribute to tumorigenesis and metastasis. Using inducible cre-recombinase and CRISPR/Cas9-mediated deletion, we investigated the roles of the histone lysine acetyltransferase TIP60 (KAT5/HTATIP) in human cells, mouse cells, and mouse embryos.

IL-21 has a critical role in establishing germinal centers by amplifying early B cell proliferation.

The proliferation and differentiation of antigen-specific B cells, including the generation of germinal centers (GC), are prerequisites for long-lasting, antibody-mediated immune protection. Affinity for antigen determines B cell recruitment, proliferation, differentiation, and competitiveness in the response, largely through determining access to T cell help. However, how T cell-derived signals contribute to these outcomes is incompletely understood.