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Abstract Background Cutaneous leishmaniasis (CL) is a neglected tropical skin disease, caused by the protozoan parasite Leishmania. In Ethiopia, CL is mainly caused by Leishmania aethiopica and can present in different clinical forms. The aim of this study was to assess whether these different forms are associated with differences in parasite genetic and host systemic immune signatures. Methods Here we analysed the whole genome sequence data for 48 clinical parasite isolates and the systemic immune signature from a cohort of CL patients, who were recruited in Nefas Mewcha, Northern Ethiopia, from January 2019 to January 2022. Results Our results show that parasites from CL cases with different presentations in a single Ethiopian setting are from the same genetic population based on a permutation test of genome-wide similarity. Furthermore, a logistic regression test for genome wide association did not identify any individual genetic variants significantly associated with disease presentation. We also measured plasma chemokine and cytokine levels of 129 CL patients presenting with different forms of CL. None of the chemokine [eotaxin, eotaxin-3, interleukin (IL)-8, interferon (IFN)-γ-induced protein-10 (IP-10), monocyte chemoattractant protein (MCP)-1, MCP-4, macrophage-derived chemokines (MDC), macrophage inflammatory protein (MIP)-1α, MIP-1β and thymus- and activation-regulated chemokine (TARC)] or cytokine (IFN-γ, IL-1β, interleukin-2, IL-4, IL-6, IL-10, IL-12p70, IL-13, tumor necrosis factor-α) levels measured were significantly different between the different clinical presentations of CL, as measured by Kruskal–Wallis test. We also compared those with healthy nonendemic controls: our results show a chemokine (IP-10, MCP-1, MCP-4, MDC, MIP-1α, MIP-1β and TARC) but not a cytokine immune signature in patients with CL as compared to healthy nonendemic controls, as measured by Mann-Whitney test. Conclusions The results of our study did not identify a systemic immune signature or parasite genetic factors associated with different clinical presentation of CL. Graphical abstract

Visceral leishmaniasis (VL) is a neglected tropical disease caused by parasites from the Leishmania (L.) donovani complex. VL is characterised by uncontrolled parasite replication in spleen, liver and bone marrow, and by an impaired immune response and high systemic levels of inflammation. Monocytes have been poorly characterised in VL patients. The aim of this study was to evaluate the expression levels of markers involved in the regulation of T cell responses on different subsets of monocytes from the blood of VL patients and healthy non-endemic controls (HNEC). Monocytes can broadly be divided into three subsets: classical, intermediate and non-classical monocytes. Our results show that the percentages of all three subsets stayed similar at the time of VL diagnosis (ToD) and at the end of anti-leishmanial treatment (EoT). We first looked at co-stimulatory receptors: the expression levels of CD40 were significantly increased on classical and intermediate, but not non-classical monocytes, at ToD as compared to EoT and HNEC. CD80 expression levels were also increased on intermediate monocytes at ToD as compared to EoT and HNEC, and on classical monocytes only as compared to HNEC. The levels of CD86 were similar at EoT and ToD and in HNEC on classical and intermediate monocytes, but significantly higher at EoT on non-classical monocytes. We also looked at an inhibitory molecule, PD-L1. Our results show that the expression levels of PD-L1 were significantly higher on all three monocyte subsets at ToD as compared to HNEC, and to EoT on classical and intermediate monocytes. These results show that monocytes from the blood of VL patients upregulate both co-stimulatory and inhibitory receptors and that their expression levels are restored at EoT.

Cutaneous leishmaniasis (CL) is a neglected tropical disease caused by Leishmania parasites, that can cause long-term chronic disabilities. The clinical presentation of CL varies in both type and severity. CL presents as three main clinical forms: localised lesions (localised cutaneous leishmaniasis, LCL); mucocutaneous leishmaniasis (MCL) that affects the mucosa of the nose or the mouth; or as disseminated not ulcerating nodules (diffuse cutaneous leishmaniasis, DCL). Here we recruited a cohort of CL patients in a newly established leishmaniasis treatment centre (LTC) in Lay Gayint, Northwest Ethiopia, and collected detailed demographic and clinical data. The results of our study show that more males than females present to the LTC to seek diagnosis and treatment. 70.2% of CL patients presented with LCL and 20.8% with MCL. A small number of patients presented with DCL, recidivans CL (a rare form of CL where new lesions appear on the edges of CL scars) or with a combination of different clinical presentations. The duration of illness varied from 1 month to 180 months. Over a third of CL patients had additional suspected CL cases in their household. Despite the majority of CL patients having heard about CL, only a minority knew about its transmission or that it could be treated. Most CL patients lived in areas where environmental factors known to be associated with the transmission of CL were present. This work highlights that CL is an important public health problem in Lay Gayint and emphasises the urgent need for more CL awareness campaigns, better health education and better disease management practices.

Abstract Background Cutaneous leishmaniasis (CL) is a neglected tropical disease that primarily affects the most vulnerable populations. In Ethiopia, where this study took place, CL is an important health problem, however, the incidence of CL is poorly monitored. Objectives This study took place in a recently established CL treatment centre, at Nefas Mewcha Hospital, Lay Gayint. This area was considered to be endemic for CL, however, no cases of CL from Lay Gayint had previously been officially reported to the Amhara Regional Health Bureau. Methods Following a CL awareness campaign, a retrospective data review was performed of patients presenting to this centre between July 2019 and March 2021. Basic demographic and clinical data were collected by a nurse and recorded in the logbook of the CL treatment centre. Results Two hundred and one patients presented for diagnosis and treatment. The age of the patients ranged from 2 to 75 years and 63.2% were males. Most patients were between 10‐ and 19‐years‐old. The majority (79.1%) of the patients presented with localised cutaneous leishmaniasis and 20.9% with mucocutaneous leishmaniasis. 98% of the patients tested positive for Leishmania parasites by microscopy. Conclusions This work underpinned how CL is a major public health problem in the Lay Gayint district. It also shows that raising awareness about CL in the community and providing diagnosis and treatment encouraged patients to travel to seek diagnosis and treatment.

Summary: Visceral leishmaniasis (VL) and HIV co-infection (VL/HIV) has emerged as a significant public health problem in Ethiopia, with up to 30% of patients with VL co-infected with HIV. These patients suffer from recurrent VL relapses and increased mortality. Those with a previous history of VL relapses (recurrent VL/HIV) experience increased VL relapses as compared to patients with HIV presenting with their first episode of VL (primary VL/HIV). Our aim was to identify drivers that account for the higher rate of VL relapses in patients with recurrent VL/HIV (n = 28) as compared to primary VL/HIV (n = 21). Our results show that the relapse-free survival in patients with recurrent VL/HIV was shorter, that they had higher parasite load, lower weight gain, and lower recovery of all blood cell lineages. Their poorer prognosis was characterized by lower production of IFN-gamma, lower CD4+ T cell counts, and higher expression of programmed cell death protein 1 (PD1) on T cells.

Visceral leishmaniasis (VL) patients co-infected with HIV (VL/HIV patients) experience frequent treatment failures, VL relapses, opportunistic infections, and higher mortality. Their immune system remains profoundly suppressed after clinical cure and they maintain higher parasite load. This is in contrast with patients with VL alone (VL patients). Since neutrophils play a critical role in the control of Leishmania replication and the regulation of immune responses, we tested the hypothesis that neutrophil activation status and effector functions are fully restored in VL, but not in VL/HIV patients. Our results show the neutrophil counts and all activation markers and effector functions tested in our study were reduced at the time of diagnosis in VL and VL/HIV patients as compared to controls. CD62L, CD63, arginase 1 expression levels and reactive oxygen species production were restored at the end of treatment in both groups. However, neutrophil counts, CD10 expression and phagocytosis remained significantly lower throughout follow-up in VL/HIV patients; suggesting that dysregulated neutrophils contribute to the impaired host defence against pathogens in VL/HIV patients.

Visceral leishmaniasis (VL) is a neglected tropical disease that causes substantial morbidity and mortality and is a growing health problem in Ethiopia, where this study took place. Most individuals infected with Leishmania donovani parasites will stay asymptomatic, but some develop VL that, if left untreated, is almost always fatal. This stage of the disease is associated with a profound immunosuppression, characterised by impaired production of Interferonγ (IFNγ), a cytokine that plays a key role in the control of Leishmania parasites, and high expression levels of an inhibitory receptor, programmed cell death 1 (PD1) on CD4+ T cells. Here, we tested the contribution of the interaction between the immune checkpoint PD1 and its ligand PDL-1 on the impaired production of IFNγ in VL patients. Our results show that in the blood of VL patients, not only CD4+, but also CD8+ T cells express high levels of PD1 at the time of VL diagnosis. Next, we identified PDL-1 expression on different monocyte subsets and neutrophils and show that PDL-1 levels were significantly increased in VL patients. PD1/PDL-1 inhibition resulted in significantly increased production of IFNγ, suggesting that therapy using immune checkpoint inhibitors might improve disease control in these patients.

Visceral leishmaniasis (VL) is the second largest cause of deaths due to parasite infections and a growing problem in East Africa. In Ethiopia, it is particularly associated with migrant workers moving from regions of nonendemicity for seasonal agricultural work and is frequently found as a coinfection with HIV, which leads to frequent VL relapse following treatment.

Systemic blood stream infections are a major threat to human health and are dramatically increasing worldwide. Pseudomonas aeruginosa is a WHO-alerted multi-resistant pathogen of extreme importance as a cause of sepsis. Septicemia patients have significantly increased survival chances if sepsis is diagnosed in the early stages. Affinity materials can not only represent attractive tools for specific diagnostics of pathogens in the blood but can prospectively also serve as the technical foundation of therapeutic filtration devices. Based on the recently developed aptamers directed against P. aeruginosa, we here present aptamer-functionalized beads for specific binding of this pathogen in blood samples. These aptamer capture beads (ACBs) are manufactured by crosslinking bovine serum albumin (BSA) in an emulsion and subsequent functionalization with the amino-modified aptamers on the bead surface using the thiol- and amino-reactive bispecific crosslinker PEG4-SPDP. Specific and quantitative binding of P. aeruginosa as the dedicated target of the ACBs was demonstrated in serum and blood. These initial but promising results may open new routes for the development of ACBs as a platform technology for fast and reliable diagnosis of bloodstream infections and, in the long term, blood filtration techniques in the fight against sepsis.

Protein hydrogels represent ideal materials for advanced cell culture applications, including 3D-cultivation of even fastidious cells. Key properties of fully functional and, at the same time, economically successful cell culture materials are excellent biocompatibility and advanced fabrication processes allowing their easy production even on a large scale based on affordable compounds. Chemical crosslinking of bovine serum albumin (BSA) with N-(3-dimethylaminopropyl)-N’-ethylcarbodiimide hydrochloride (EDC) in a water-in-oil emulsion with isoparaffinic oil as the continuous phase and sorbitan monooleate as surfactant generates micro-meter-scale spherical particles. They allow a significant simplification of an indispensable and laborious step in traditional cell culture workflows. This cell passaging (or splitting) to fresh culture vessels/flasks conventionally requires harsh trypsinization, which can be omitted by using the “trans-ferry-beads” presented here. When added to different pre-cultivated adherent cell lines, the beads are efficiently boarded by cells as passengers and can be easily transferred afterward for the embarkment of novel flasks. After this procedure, cells are perfectly viable and show normal growth behavior. Thus, the trans-ferry-beads not only may become extremely affordable as a final product but also may generally replace trypsinization in conventional cell culture, thereby opening new routes for the establishment of optimized and resource-efficient workflows in biological and medical cell culture laboratories.

Leishmaniasis is the world's second deadliest parasitic disease after malaria, and current treatment of the different forms of this disease is far from satisfactory. Alkylphospholipid analogs (APLs) are a family of anticancer drugs that show antileishmanial activity, including the first oral drug (miltefosine) for leishmaniasis and drugs in preclinical/clinical oncology trials, but their precise mechanism of action remains to be elucidated.Here we show that the tumor cell apoptosis-inducer edelfosine was the most effective APL, as compared to miltefosine, perifosine and erucylphosphocholine, in killing Leishmania spp. promastigotes and amastigotes as well as tumor cells, as assessed by DNA breakdown determined by flow cytometry. In studies using animal models, we found that orally-administered edelfosine showed a potent in vivo antileishmanial activity and diminished macrophage pro-inflammatory responses. Edelfosine was also able to kill Leishmania axenic amastigotes. Edelfosine was taken up by host macrophages and killed intracellular Leishmania amastigotes in infected macrophages. Edelfosine accumulated in tumor cell mitochondria and Leishmania kinetoplast-mitochondrion, and led to mitochondrial transmembrane potential disruption, and to the successive breakdown of parasite mitochondrial and nuclear DNA. Ectopic expression of Bcl-XL inhibited edelfosine-induced cell death in both Leishmania parasites and tumor cells. We found that the cytotoxic activity of edelfosine against Leishmania parasites and tumor cells was associated with a dramatic recruitment of FOF1-ATP synthase into lipid rafts following edelfosine treatment in both parasites and cancer cells. Raft disruption and specific FOF1-ATP synthase inhibition hindered edelfosine-induced cell death in both Leishmania parasites and tumor cells. Genetic deletion of FOF1-ATP synthase led to edelfosine drug resistance in Saccharomyces cerevisiae yeast.The present study shows that the antileishmanial and anticancer actions of edelfosine share some common signaling processes, with mitochondria and raft-located FOF1-ATP synthase being critical in the killing process, thus identifying novel druggable targets for the treatment of leishmaniasis.

Visceral leishmaniasis (VL) is a neglected tropical disease that affects the poorest communities and can cause substantial morbidity and mortality. Visceral leishmaniasis is characterized by the presence of Leishmania parasites in the spleen, liver and bone marrow, hepatosplenomegaly, pancytopenia, prolonged fever, systemic inflammation and low body mass index (BMI). The factors impacting on the severity of VL are poorly characterized. Here we performed a cross-sectional study to assess whether co-infection of VL patients with intestinal parasites influences disease severity, assessed with clinical and haematological data, inflammation, cytokine profiles and BMI. Data from VL patients was similar to VL patients co-infected with intestinal parasites, suggesting that co-infection of VL patients with intestinal parasites does not alter disease severity.

Accurate diagnosis of cutaneous leishmaniasis (CL) is important for chemotherapy and epidemiological studies. Common approaches for Leishmania detection involve the invasive collection of specimens for direct identification of amastigotes by microscopy and the culturing of promastigotes from infected tissues. Although these techniques are highly specific, they require highly skilled health workers and have the inherent risks of all invasive procedures, such as pain and risk of bacterial and fungal super-infection. Therefore, it is essential to reduce discomfort, potential infection and scarring caused by invasive diagnostic approaches especially for children. In this report, we present a novel non-invasive method, that is painless, rapid and user-friendly, using sequential tape strips for sampling and isolation of DNA from the surface of active and healed skin lesions of CL patients. A total of 119 patients suspected of suffering from cutaneous leishmaniasis with different clinical manifestations were recruited and samples were collected both from their lesions and from uninfected areas. In addition, 15 fungal-infected lesions and 54 areas of healthy skin were examined. The duration of sampling is short (less than one minute) and species identification by PCR is highly specific and sensitive. The sequential tape stripping sampling method is a sensitive, non-invasive and cost-effective alternative to traditional diagnostic assays and it is suitable for field studies as well as for use in health care centers.

One of the key immunological characteristics of active visceral leishmaniasis (VL) is a profound immunosuppression and impaired production of Interferon-γ (IFN-γ). However, recent studies from Bihar in India showed using a whole blood assay, that whole blood cells have maintained the capacity to produce IFN-γ. Here we tested the hypothesis that a population of low-density granulocytes (LDG) might contribute to T cell responses hyporesponsiveness via the release of arginase. Our results show that this population is affected by the anticoagulant used to collect blood: the frequency of LDGs is significantly lower when the blood is collected with heparin as compared to EDTA; however, the anticoagulant does not impact on the levels of arginase released. Next, we assessed the capacity of whole blood cells from patients with active VL to produce IFN-γ and IL-10 in response to antigen-specific and polyclonal activation. Our results show that whole blood cells produce low or levels below detection limit of IFN-γ and IL-10, however, after successful treatment of VL patients, these cells gradually regain their capacity to produce IFN-γ, but not IL-10, in response to activation. These results suggest that in contrast to VL patients from Bihar, India, whole blood cells from VL patients from Gondar, Ethiopia, have lost their ability to produce IFN-γ during active VL and that active disease is not associated with sustained levels of IL-10 production following stimulation.

Surgical site infections (SSIs) are one of the most common nosocomial infections, which can result in serious complications after surgical interventions. Foreign materials such as implants or surgical sutures are optimal surfaces for the adherence of bacteria and subsequent colonization and biofilm formation. Due to a significant increase in antibiotic-resistant bacterial strains, naturally occurring agents exhibiting antibacterial properties have great potential in prophylactic therapies. The aim of this study was to develop a coating for surgical sutures consisting of the antibacterial substance totarol, a naturally occurring diterpenoid isolated from Podocarpus totara in combination with poly(lactide-co-glycolide acid) (PLGA) as a biodegradable drug delivery system. Hence, non-absorbable monofilament and multifilament sutures were coated with solutions containing different amounts and ratios of totarol and PLGA, resulting in a smooth, crystalline coating. Using an agar diffusion test (ADT), it became evident that the PLGA/totarol-coated sutures inhibited the growth of Staphylococcus aureus over a period of 15 days. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that the coated sutures were not cytotoxic to murine fibroblasts. Overall, the data indicates that our innovative, biodegradable suture coating has the potential to reduce the risk of SSIs and postoperative biofilm-formation on suture material without adverse effects on tissue.

We have previously shown that in successful pregnancies increased arginase activity is a mechanism that contributes to the suppression of the maternal immune system. We identified the main type of arginase-expressing cells as a population of activated low-density granulocytes (LDGs) in peripheral blood mononuclear cells and in term placentae. In the present study, we analyzed the phenotype of LDGs and compared it to the phenotype of normal density granulocytes (NDGs) in maternal peripheral blood, placental biopsies and cord blood. Our data reveal that only LDGs but no NDGs could be detected in placental biopsies. Phenotypically, NDGs and LDGs from both maternal and cord blood expressed different levels of maturation, activation and degranulation markers. NDGs from the maternal and cord blood were phenotypically similar, while maternal, cord and placental LDGs showed different expression levels of CD66b. LDGs present in cord blood expressed higher levels of arginase compared to maternal and placental LDGs. In summary, our results show that in maternal and cord blood, two phenotypically different populations of neutrophils can be identified, whereas in term placentae, only activated neutrophils are present.

The underlying mechanisms resulting in the profound immune suppression characteristic of human visceral leishmaniasis (VL) are not fully understood. Here, we tested the hypothesis that arginase, an enzyme associated with immunosuppression, is higher in patients with VL and contributes to impaired T cell responses. We recruited patients with VL before and after treatment and healthy controls and measured the arginase metabolism in the blood of these individuals. Our results show that arginase activity is significantly higher in the blood of patients with active VL as compared to controls. These high levels of arginase decline considerably once the patients are successfully treated. We identified the phenotype of arginase-expressing cells among PBMCs as neutrophils and show that their frequency was increased in PBMCs of patients before treatment; this coincides with reduced levels of L-arginine in the plasma and decreased expression levels of CD3ζ in T cells.

We have recently identified a novel population of activated low-density granulocytes (LDGs) in peripheral blood mononuclear cells of HIV seropositive patients. LDGs have a similar morphology to normal density granulocytes (NDGs), but are phenotypically different. Here we measured the expression levels of different phenotypic markers of granulocytes in the blood of HIV seropositive patients at different stages of HIV infection to determine whether the phenotype of NDGs and LDGs are affected by disease severity. Our results reveal that the phenotype of NDGs, but not that of LDGs, varies according to the severity of the disease.

Visceral leishmaniasis is a parasitic disease associated with high mortality. The most important foci of visceral leishmaniasis in Ethiopia are in the Northwest and are predominantly associated with high rates of HIV co-infection. Co-infection of visceral leishmaniasis patients with HIV results in higher mortality, treatment failure and relapse. We have previously shown that arginase, an enzyme associated with immunosuppression, was increased in patients with visceral leishmaniasis and in HIV seropositive patients; further our results showed that high arginase activity is a marker of disease severity. Here, we tested the hypothesis that increased arginase activities associated with visceral leishmaniasis and HIV infections synergize in patients co-infected with both pathogens.We recruited a cohort of patients with visceral leishmaniasis and a cohort of patients with visceral leishmaniasis and HIV infection from Gondar, Northwest Ethiopia, and recorded and compared their clinical data. Further, we measured the levels of arginase activity in the blood of these patients and identified the phenotype of arginase-expressing cells. Our results show that CD4(+) T cell counts were significantly lower and the parasite load in the spleen was significantly higher in co-infected patients. Moreover, our results demonstrate that arginase activity was significantly higher in peripheral blood mononuclear cells and plasma of co-infected patients. Finally, we identified the cells-expressing arginase in the PBMCs as low-density granulocytes.Our results suggest that increased arginase might contribute to the poor disease outcome characteristic of patients with visceral leishmaniasis and HIV co-infection.

Tumor-growth is often associated with the expansion of myeloid derived suppressor cells that lead to local or systemic arginine depletion via the enzyme arginase. It is generally assumed that this arginine deficiency induces a global shut-down of T cell activation with ensuing tumor immune escape. While the impact of arginine depletion on polyclonal T cell proliferation and cytokine secretion is well documented, its influence on chemotaxis, cytotoxicity and antigen specific activation of human T cells has not been demonstrated so far. We show here that chemotaxis and early calcium signaling of human T cells are unimpaired in the absence of arginine. We then analyzed CD8(+) T cell activation in a tumor peptide as well as a viral peptide antigen specific system: (i) CD8(+) T cells with specificity against the MART-1aa26-35*A27L tumor antigen expanded with in vitro generated dendritic cells, and (ii) clonal CMV pp65aa495-503 specific T cells and T cells retrovirally transduced with a CMV pp65aa495-503 specific T cell receptor were analyzed. Our data demonstrate that human CD8(+) T cell antigen specific cytotoxicity and perforin secretion are completely preserved in the absence of arginine, while antigen specific proliferation as well as IFN-γ and granzyme B secretion are severely compromised. These novel results highlight the complexity of antigen specific T cell activation and demonstrate that human T cells can preserve important activation-induced effector functions in the context of arginine deficiency.

The mechanisms resulting in progressive immune dysfunction during the chronic phase of HIV infection are not fully understood. We have previously shown that arginase, an enzyme with potent immunosuppressive properties, is increased in HIV seropositive (HIV+) patients with low CD4(+) T cell counts. Here we show that the cells expressing arginase in peripheral blood mononuclear cells of HIV+ patients are low-density granulocytes (LDGs) and that whereas these cells have a similar morphology to normal-density granulocyte, they are phenotypically different. Importantly, our results reveal that increased frequencies of LDGs correlate with disease severity in HIV+ patients.

Cutaneous leishmaniasis is a vector-borne disease that is in Ethiopia mainly caused by the parasite Leishmania aethiopica. This neglected tropical disease is common in rural areas and causes serious morbidity. Persistent nonhealing cutaneous leishmaniasis has been associated with poor T cell mediated responses; however, the underlying mechanisms are not well understood.We have recently shown in an experimental model of cutaneous leishmaniasis that arginase-induced L-arginine metabolism suppresses antigen-specific T cell responses at the site of pathology, but not in the periphery. To test whether these results translate to human disease, we recruited patients presenting with localized lesions of cutaneous leishmaniasis and assessed the levels of arginase activity in cells isolated from peripheral blood and from skin biopsies. Arginase activity was similar in peripheral blood mononuclear cells (PBMCs) from patients and healthy controls. In sharp contrast, arginase activity was significantly increased in lesion biopsies of patients with localized cutaneous leishmaniasis as compared with controls. Furthermore, we found that the expression levels of CD3ζ, CD4 and CD8 molecules were considerably lower at the site of pathology as compared to those observed in paired PBMCs.Our results suggest that increased arginase in lesions of patients with cutaneous leishmaniasis might play a role in the pathogenesis of the disease by impairing T cell effector functions.

BACKGROUND: The leishmaniases are a complex of neglected tropical diseases caused by more than 20 Leishmania parasite species, for which available therapeutic arsenal is scarce and unsatisfactory. Pentavalent antimonials (SbV) are currently the first-line pharmacologic therapy for leishmaniasis worldwide, but resistance to these compounds is increasingly reported. Alkyl-lysophospoholipid analogs (ALPs) constitute a family of compounds with antileishmanial activity, and one of its members, miltefosine, has been approved as the first oral treatment for visceral and cutaneous leishmaniasis. However, its clinical use can be challenged by less impressive efficiency in patients infected with some Leishmania species, including L. braziliensis and L. mexicana, and by proneness to develop drug resistance in vitro. METHODOLOGY/PRINCIPAL FINDINGS: We found that ALPs ranked edelfosine>perifosine>miltefosine>erucylphosphocholine for their antileishmanial activity and capacity to promote apoptosis-like parasitic cell death in promastigote and amastigote forms of distinct Leishmania spp., as assessed by proliferation and flow cytometry assays. Effective antileishmanial ALP concentrations were dependent on both the parasite species and their development stage. Edelfosine accumulated in and killed intracellular Leishmania parasites within macrophages. In vivo antileishmanial activity was demonstrated following oral treatment with edelfosine of mice and hamsters infected with L. major, L. panamensis or L. braziliensis, without any significant side-effect. Edelfosine also killed SbV-resistant Leishmania parasites in in vitro and in vivo assays, and required longer incubation times than miltefosine to generate drug resistance. CONCLUSIONS/SIGNIFICANCE: Our data reveal that edelfosine is the most potent ALP in killing different Leishmania spp., and it is less prone to lead to drug resistance development than miltefosine. Edelfosine is effective in killing Leishmania in culture and within macrophages, as well as in animal models infected with different Leishmania spp. and SbV-resistant parasites. Our results indicate that edelfosine is a promising orally administered antileishmanial drug for clinical evaluation.

CD1d is a nonpolymorphic MHC class I-like molecule which presents nonpeptide ligands, e.g. glycolipids, to NKT cells. These cells are known to have multiple effects on innate and adaptive immune responses and on the development of pathological conditions. In order to analyze CD1d expression and function in the rat, the first rat CD1d-specific monoclonal antibodies (mAbs) were generated.Two mAbs, WTH-1 and WTH-2, were generated which bound equally well to cell surface-expressed rat and mouse CD1d. Their non-overlapping epitopes were mapped to the CD1d heavy chain. Flow cytometry and immunohistological analyses revealed a nearly identical degree and pattern of CD1d expression for hematopoieitic cells of both species. Notable is also the detection of CD1d protein in mouse and rat Paneth cells as well as the extremely high CD1d expression in acinar exocrine cells of the rat pancreas and the expression of CD4 on rat marginal zone B cells. Both mAbs blocked α-galactosylceramide recognition by primary rat and mouse NKT cells. Interestingly, the two mAbs differed in their impact on the activation of various autoreactive T cell hybridomas, including the XV19.2 hybridoma whose activation was enhanced by the WTH-1 mAb.The two novel monoclonal antibodies described in this study, allowed the analysis of CD1d expression and CD1d-restricted T cell responses in the rat for the first time. Moreover, they provided new insights into mechanisms of CD1d-restricted antigen recognition. While CD1d expression by hematopoietic cells of mice and rats was extremely similar, CD1d protein was detected at not yet described sites of non-lymphatic tissues such as the rat exocrine pancreas and Paneth cells. The latter is of special relevance given the recently reported defects of Paneth cells in CD1d(-/-) mice, which resulted in an altered composition of the gut flora.

All natural Leishmania infections start in the skin; however, little is known of the contribution made by the sand fly vector to the earliest events in mammalian infection, especially in inflamed skin that can rapidly kill invading parasites. During transmission sand flies regurgitate a proteophosphoglycan gel synthesized by the parasites inside the fly midgut, termed promastigote secretory gel (PSG). Regurgitated PSG can exacerbate cutaneous leishmaniasis. Here, we show that the amount of Leishmania mexicana PSG regurgitated by Lutzomyia longipalpis sand flies is proportional to the size of its original midgut infection and the number of parasites transmitted. Furthermore, PSG could exacerbate cutaneous L. mexicana infection for a wide range of doses (10-10,000 parasites) and enhance infection by as early as 48 hours in inflamed dermal air pouches. This early exacerbation was attributed to two fundamental properties of PSG: Firstly, PSG powerfully recruited macrophages to the dermal site of infection within 24 hours. Secondly, PSG enhanced alternative activation and arginase activity of host macrophages, thereby increasing L-arginine catabolism and the synthesis of polyamines essential for intracellular parasite growth. The increase in arginase activity promoted the intracellular growth of L. mexicana within classically activated macrophages, and inhibition of macrophage arginase completely ablated the early exacerbatory properties of PSG in vitro and in vivo. Thus, PSG is an essential component of the infectious sand fly bite for the early establishment of Leishmania in skin, which should be considered when designing and screening therapies against leishmaniasis.

The balance between T helper (Th) 1 and Th2 cell responses is a major determinant of the outcome of experimental leishmaniasis, but polarized Th1 or Th2 responses are not sufficient to account for healing or nonhealing. Here we show that high arginase activity, a hallmark of nonhealing disease, is primarily expressed locally at the site of pathology. The high arginase activity causes local depletion of L-arginine, which impairs the capacity of T cells in the lesion to proliferate and to produce interferon-gamma, while T cells in the local draining lymph nodes respond normally. Healing, induced by chemotherapy, resulted in control of arginase activity and reversal of local immunosuppression. Moreover, competitive inhibition of arginase as well as supplementation with L-arginine restored T cell effector functions and reduced pathology and parasite growth at the site of lesions. These results demonstrate that in nonhealing leishmaniasis, arginase-induced L-arginine depletion results in impaired T cell responses. Our results identify a novel mechanism in leishmaniasis that contributes to the failure to heal persistent lesions and suggest new approaches to therapy.

The leishmaniases are a group of vector-borne parasitic diseases that represent a major international public health problem; they belong to the most neglected tropical diseases and have one of the highest rates of morbidity and mortality. The clinical outcome of infection with Leishmania parasites depends on a variety of factors such as parasite species, vector-derived products, genetics, behaviour, and nutrition. The age of the infected individuals also appears to be critical, as a significant proportion of clinical cases occur in children; this age-related higher prevalence of disease is most remarkable in visceral leishmaniasis. The mechanisms resulting in this higher incidence of clinical disease in children are poorly understood. We have recently revealed that sustained arginase activity promotes uncontrolled parasite growth and pathology in vivo. Here, we tested the hypothesis that arginase-mediated L-arginine metabolism differs with age.The age distribution of patients with visceral or cutaneous leishmaniasis was determined in cohorts of patients in our clinics in endemic areas in Ethiopia. To exclude factors that are difficult to control in patients, we assessed the impact of ageing on the manifestations of experimental leishmaniasis. We determined parasite burden, T cell responses, and macrophage effector functions in young and aged mice during the course of infection.Our results show that younger mice develop exacerbated lesion pathology and higher parasite burdens than aged mice. This aggravated disease development in younger individuals does not correlate with a change in T helper cytokine profile. To address the underlying mechanisms responsible for the more severe infections in younger mice, we investigated macrophage effector functions. Our results show that macrophages from younger mice do not have an impaired capacity to kill parasites; however, they express significantly higher levels of arginase 1 than aged mice and promote parasite growth more efficiently. Thus, our results demonstrate that ageing differentially impacts on L-arginine metabolism and subsequent effector functions of physiologically distinct macrophage subsets.Here, we show that arginase-mediated L-arginine metabolism is modulated with age and affects the capacity of macrophages to express arginase; the increased capacity to upregulate this enzyme in younger individuals results in a more permissive environment for parasite growth, increased disease severity and pathology. These results suggest that the difference in arginase-mediated L-arginine catabolism is likely to be an important factor contributing to the increased incidence of clinical cases in children. Thus, targeting L-arginine metabolism might be a promising therapeutic strategy against leishmaniasis, especially in children and young adults.

La Universidad del Valle me hizo la gentileza de invitarme a participar en esta fiesta de la inteligencia. Se traté de la presentación de dos obras de profesores suyos, editadas casi simultáneamente por su centro editorial: un libro de Mario Díaz, “El Campo Intelectual de la Educación”, impreso en el mes de noviembre, y otro de Humberto Quiceno, “Los Intelectuales y el Saber”, impreso en diciembre de 1993. Lo de la simultaneidad es importante, porque los dos libros tienen mucho más en común que sus fechas de impresión: similitudes de origen, de objetivos y fines, y parcial coincidencia de temas. Ambos tienen en Michel Foucault un término de referencia, el primero parcial, el segundo total; ambos tratan de aclarar y hacer explícitas posiciones de lucha, en la teoría y en la práctica, sobre el tema de los intelectuales. En cuanto a esto último, las fechas pudieron ser invertidas: primero Humberto Quiceno, por la generalidad del tema, después Mario Díaz, por su especificidad.

En 1872 llegó a Colombia la primera Misión Pedagógica Alemana, solicitada por el presidente de los Estados Unidos de Colombia, general Eustorgio Salgar, quien el 1~ de noviembre de 1870 había expedido el Decreto Orgánico de la Instrucción Pública Primaria, cuyos capítulos V, VI y VII (artículos 114 a 137) y IX (artículos 194 a 209) están dedicados a la Escuela Central y a las Escuelas Normales. La Escuela Central se creaba en la capital de la Unión, “con el objeto de formar maestros que rejenten las escuelas normales”; las escuelas normales se establecían en la capital de cada Estado, con excepción del de Cundinamarca, “con el objeto de formar maestros idóneos que rejenten las escuelas elementales y las superiores”. La Misión Pedagógica Alemana venía con el encargo de organizar el sistema de las escuelas normales. Por qué una misión alemana, si la educación había estado desde la época de la independencia bajo la influencia de Francia y de Inglaterra, y no de Alemania? ¿Qué había detrás, y en el fondo, de esta decisión de gobierno?

This case report aims to describe a modified surgically assisted rapid palatal expansion technique to treat an asymmetrical posterior crossbite with no mandibular shift without causing an interincisal diastema. A clinical patient with an asymmetrical crossbite, large tooth-size-arch length, and Bolton discrepancy is used to illustrate the modified technique. Instead of traditional osteotomies, in this technique, the osteotomy is done between the maxillary right canine and lateral incisor (connecting the piriform aperture to the alveolar process) along with a unilateral LeFort I osteotomy. The expansion forces are produced by the activation of a conventional hyrax appliance. The skeletal unilateral crossbite was corrected without major changes to the opposite side and without causing an anesthetic diastema between the maxillary central incisors. A mandibular incisor extraction produced the space needed to treat the tooth size-arch length and corrected the Bolton discrepancy. This allowed a successful treatment of the problems initially presented by the patient. • An asymmetric skeletal crossbite was treated using a modified SARPE technique. • The modified SARPE technique moved the undesired central incisor diastema to a more lateral region. • Treatment allowed asymmetrical expansion with neglectable effects on the unaffected side. [ABSTRACT FROM AUTHOR]

Abstract Background Cellulitis is a painful infection of the skin and underlying tissues, commonly affecting the lower leg. Approximately one‐third of people experience recurrence. Nurses who work in general practice (practice nurses) and see people at home (community or district nurses) could have an important role in managing risk factors for cellulitis, such as long‐term leg swelling, wound care and skin care. Objective To explore practice and community nurses' views and experiences of helping people to manage risk factors for recurrent lower limb cellulitis. Methods Semi‐structured, telephone interviews with 21 practice and community nurses in England from October 2020 to March 2021. Interviews were transcribed verbatim and analysed using reflexive thematic analysis. Results Nurses face multiple challenges when supporting people to manage risk factors for recurrent lower limb cellulitis. Key challenges include limited time and access to resources such as Doppler equipment, and the physical and psychosocial capabilities of patients to self‐manage. Nurses identified potential strategies to overcome these challenges, such as placing greater emphasis on prevention and supporting self‐management by providing resources for patients and support networks (paid and unpaid carers) to reinforce knowledge post‐consultation and develop skills to self‐care. Conclusions We identified a need to develop and evaluate resources, such as support materials, for nurses to use to help patients reduce their risk of recurrent cellulitis.

Background Acne is common, can cause significant impact on quality of life and is a frequent reason for long-term antibiotic use. Spironolactone has been prescribed for acne in women for many years, but robust evidence is lacking. Objective To evaluate whether spironolactone is clinically effective and cost-effective in treating acne in women. Design Pragmatic, parallel, double-blind, randomised superiority trial. Setting Primary and secondary healthcare and community settings (community and social media advertising). Participants Women aged 18 years and older with facial acne persisting for at least 6 months, judged to potentially warrant oral antibiotic treatment. Interventions Participants were randomised 1 : 1, using an independent web-based procedure, to either 50 mg/day spironolactone or matched placebo until week 6, increasing to 100 mg/day spironolactone or matched placebo until week 24. Participants continued usual topical treatment. Main outcome measures Primary outcome was the adjusted mean difference in Acne-Specific Quality of Life symptom subscale score at 12 weeks. Secondary outcomes included Acne-Specific Quality of Life total and subscales; participant self-assessed improvement; Investigator’s Global Assessment; Participant’s Global Assessment; satisfaction; adverse effects and cost-effectiveness. Results Of 1267 women assessed for eligibility, 410 were randomised (201 intervention, 209 control), 342 in the primary analysis (176 intervention, 166 control). Mean age was 29.2 years (standard deviation 7.2) and 7.9% (28/356) were from non-white backgrounds. At baseline, Investigator’s Global Assessment classified acne as mild in 46%, moderate in 40% and severe in 13%. At baseline, 82.9% were using topical treatments. Over 95% of participants in both groups tolerated the treatment and increased their dose. Mean baseline Acne-Specific Quality of Life symptom subscale was 13.0 (standard deviation 4.7) across both groups. Mean scores at week 12 were 19.2 (standard deviation 6.1) for spironolactone and 17.8 (standard deviation 5.6) for placebo [difference favouring spironolactone 1.27 (95% confidence interval 0.07 to 2.46) adjusting for baseline variables]. Mean scores at week 24 were 21.2 (standard deviation 5.9) in spironolactone group and 17.4 (standard deviation 5.8) in placebo group [adjusted difference 3.77 (95% confidence interval 2.50 to 5.03) adjusted]. Secondary outcomes also favoured spironolactone at 12 weeks with greater differences at 24 weeks. Participants taking spironolactone were more likely than those taking placebo to report overall acne improvement at 12 weeks {72.2% vs. 67.9% [adjusted odds ratio 1.16 (95% confidence interval 0.70 to 1.91)]} and at 24 weeks {81.9% vs. 63.3% [adjusted odds ratio 2.72 (95% confidence interval 1.50 to 4.93)]}. Investigator’s Global Assessment was judged successful at week 12 for 31/201 (18.5%) taking spironolactone and 9/209 (5.6%) taking placebo [adjusted odds ratio 5.18 (95% confidence interval 2.18 to 12.28)]. Satisfaction with treatment improved in 70.6% of participants taking spironolactone compared with 43.1% taking placebo [adjusted odds ratio 3.12 (95% confidence interval 1.80 to 5.41)]. Adverse reactions were similar between groups, but headaches were reported more commonly on spironolactone (20.4% vs. 12.0%). No serious adverse reactions were reported. Taking account for missing data through multiple imputation gave an incremental cost per quality-adjusted life-year of £27,879 (adjusted) compared to placebo or £2683 per quality-adjusted life-year compared to oral antibiotics. Conclusions Spironolactone resulted in better participant-reported and investigator-reported outcomes than placebo, with greater differences at week 24 than week 12. Trial registration This trial is registered as ISRCTN12892056 and EudraCT (2018-003630-33). Funding This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 16/13/02) and is published in full in Health Technology Assessment; Vol. 28, No. 56. See the NIHR Funding and Awards website for further award information. Plain language summary What was the question? Acne (or spots) is common and often persists into adulthood. Many people take long courses of antibiotic tablets, but concerns about antibiotic resistance mean alternatives are needed. Spironolactone is a medicine that is sometimes used for acne in women. However, we do not know whether it works. This trial aimed to answer this question. What did we do? We invited women aged over 18 who had acne on their face for at least 6 months to take part via their general practitioner surgery, hospital or advertising. Women were randomly assigned to two groups: one group was given spironolactone and the other group was given identical-looking placebo (‘dummy pill’) daily for 24 weeks. Women in both groups could continue using acne treatments applied to the skin (gels/creams/lotions). We asked participants to rate their acne using a questionnaire called Acne-Specific Quality of Life, asked whether they felt their skin had improved and asked skin specialists to assess their skin. What did we find? Four hundred and ten women took part, many of whom had had acne for a long time. Acne-Specific Quality of Life scores improved in both groups by 12 weeks but improved more in the spironolactone group at 12 and 24 weeks. When asked directly whether their skin had improved, 71% of participants in the spironolactone group said it had, compared with 43% on placebo. Skin specialists were also more likely to report that the acne had improved in the spironolactone group. Side effects were mild and similar in both groups but there were slightly more headaches on spironolactone (20% compared with 12%). Spironolactone is likely to represent value for money for the National Health Service, though this depends on a number of factors including what it is compared to. What does this mean? This trial suggests that spironolactone is a useful additional treatment for women with persistent acne. Scientific summary Background Acne vulgaris (hereon ‘acne’) is common, can cause significant psychosocial impact and risks permanent scarring. Topical treatments are first line, but people commonly receive long courses of oral antibiotics, raising concerns regarding antimicrobial resistance. Spironolactone, a potassium-sparing diuretic, is widely used for other conditions, such as hypertension. Spironolactone has anti-androgenic properties and is prescribed by dermatologists to treat acne in women, but robust evidence of effectiveness is lacking. Objective To evaluate whether spironolactone is clinically effective and cost-effective in treating persistent facial acne in women. Methods Design This was a pragmatic, multicentre, participant-blinded and clinician-blinded, placebo-controlled randomised trial. Participants were recruited through primary care (search and mail-out or opportunistic recruitment), secondary care (opportunistic recruitment) and advertising, including community and social media advertising. Trial participants were randomised to receive either 50 mg spironolactone or matched placebo one tablet daily for the first 6 weeks and then two tablets daily (total 100 mg spironolactone or matched placebo) at (or after) week 6, providing the participant was tolerating any side effects. Treatment continued for 24 weeks in both groups. Participants in both groups could continue to use usual topical treatments throughout the trial but adherence to topicals was not promoted beyond usual care. Between baseline and week 12, participants were asked not to change their topical treatments and not to take oral treatments for acne such as oral antibiotics, hormonal treatments or isotretinoin. After week 12, participants could change usual acne care, including oral treatments, if needed. In both groups, spironolactone or placebo was stopped at week 24, participants were informed of their treatment allocation and entered an unblinded follow-up period up to week 52. After week 24, participants could seek any treatment from their usual clinical team, including spironolactone. Baseline assessment was carried out in secondary care to ensure standardisation of clinical assessments, as the Investigator’s Global Assessment (IGA) for acne is not commonly used in primary care and was an important secondary outcome. The baseline appointment included pregnancy test, blood test (to exclude renal impairment or raised serum potassium), participant photo to aid recall about changes in acne, and contraceptive counselling. Baseline visits were conducted by research nurses and/or dermatologists. Participants were followed up face-to-face (or by video call or telephone due to the COVID-19 pandemic) in secondary care at week 6 and week 12, with primary outcome assessment at week 12, and longer-term follow-up by questionnaires at week 24 and up to week 52. Participants Participants eligible for inclusion were women aged 18 years or over: with facial acne vulgaris for at least 6 months acne of sufficient severity to warrant oral antibiotics, as judged by trial clinician; and with IGA ≥ 2 (mild or worse) women of childbearing potential at risk of pregnancy had to be willing to use their usual hormonal or barrier method of contraception for the first 6 months of the trial and for at least 4 weeks afterwards willing to be randomised sufficient English to self-complete acne-specific quality of life (Acne-QoL). Potential participants were excluded if: IGA acne grade was 0–1 (clear or almost clear) ever taken spironolactone taken oral isotretinoin within past 6 months taken oral antibiotics (lasting longer than 1 week) for acne within previous month started, stopped or changed hormonal contraception, co-cyprindiol or other hormonal treatment within past 3 months or planning to start, stop or change within the next 3 months intending to become pregnant in next 6 months spironolactone contraindicated: currently taking potassium-sparing diuretic, angiotensin-converting enzyme inhibitor, angiotensin II receptor blocker or digoxin hereditary problems of galactose intolerance, lactase deficiency or glucose–galactose malabsorption (as the spironolactone and placebo tablets contain lactose) androgen-secreting adrenal or ovarian tumour Cushing syndrome congenital adrenal hyperplasia estimated glomerular filtration rate below 60 ml/minute/1.73 m2 serum potassium level above upper limit of reference range for laboratory. Outcomes Primary outcome was comparison of mean Acne-QoL symptom subscale scores between groups at week 12. Acne-QoL contains 19 questions with seven response categories, each referring to the past week, reported in four domains (acne symptoms, self-perception, role-social, role-emotional). Secondary outcomes included: Acne-QoL symptom subscale score at week 24 and up to week 52 Acne-QoL other subscales (self-perception, role-emotional and role-social) at week 12, week 24 and up to week 52 participant self-assessed overall improvement at week 12 recorded on six-point Likert scale (with baseline photo to aid recall) IGA change from baseline to week 12 Participant’s Global Assessment (PGA) change at week 12 and week 24 generic health-related quality of life at week 6, week 12, week 24 and up to week 52 [EuroQol-5 Dimensions, five-level version (EQ-5D-5L)] adverse reactions use of oral acne treatment during follow-up (e.g. antibiotics, isotretinoin) resource use. Sample size Sample size calculation was based on Acne-QoL symptom subscale scores as recommended by the questionnaire developer. Based on comparison Acne-QoL symptom subscale scores between groups at week 12, power 90%, alpha 0.05 and seeking a difference of 2 points between groups (effect size 0.35), a target sample size of 346 participants was initially estimated, or 434 participants allowing for 20% loss to follow-up. During the trial, the target sample size was revised to allow for correlation between baseline and follow-up measures, following discussion with trial monitoring committees and funder. Allowing for a correlation with baseline of 0.293 and a deflation factor of 1-ρ2, gave a revised target sample size of 398 participants (including allowing for 20% loss to follow-up). Randomisation and blinding Participants were randomised in a 1 : 1 ratio to either spironolactone or matched placebo using an independent web-based system (block sizes 2 and 4). Participants were stratified by recruitment centre and baseline acne severity (IGA