Distinct ontogenetic lineages dictate cDC2 heterogeneity.

Conventional dendritic cells (cDCs) include functionally and phenotypically diverse populations, such as cDC1s and cDC2s. The latter population has been variously subdivided into Notch-dependent cDC2s, KLF4-dependent cDC2s, T-bet cDC2As and T-bet cDC2Bs, but it is unclear how all these subtypes are interrelated and to what degree they represent cell states or cell subsets. All cDCs are derived from bone marrow progenitors called pre-cDCs, which circulate through the blood to colonize peripheral tissues.

Distinct transcriptomic signatures define febrile malaria depending on initial infective states, asymptomatic or uninfected.

Background: Cumulative malaria parasite exposure in endemic regions often results in the acquisition of partial immunity and asymptomatic infections. There is limited information on how host-parasite interactions mediate the maintenance of chronic symptomless infections that sustain malaria transmission.

Methods: Here, we determined the gene expression profiles of the parasite population and the corresponding host peripheral blood mononuclear cells (PBMCs) from 21 children (< 15 years).

Acquisition of suppressive function by conventional T cells limits antitumor immunity upon T depletion.

Regulatory T (T) cells contribute to immune homeostasis but suppress immune responses to cancer. Strategies to disrupt T cell-mediated cancer immunosuppression have been met with limited clinical success, but the underlying mechanisms for treatment failure are poorly understood. By modeling T cell-targeted immunotherapy in mice, we find that CD4 Foxp3 conventional T (T) cells acquire suppressive function upon depletion of Foxp3 T cells, limiting therapeutic efficacy.

Antibody-dependent immune responses elicited by blood stage-malaria infection contribute to protective immunity to the pre-erythrocytic stages.

Advances in transcriptomics and proteomics have revealed that different life-cycle stages of the malaria parasite, share antigens, thus allowing for the possibility of eliciting immunity to a parasite life-cycle stage that has not been experienced before. Using the (AS strain) model of malaria in mice, we investigated how isolated exposure to blood-stage infection, bypassing a liver-stage infection, yields significant protection to sporozoite challenge resulting in lower liver parasite burdens. Antibodies are the main immune driver of this protection.

Differential Trafficking and Expression of PIR Proteins in Acute and Chronic Infections.

multigene families are thought to play important roles in the pathogenesis of malaria. genes comprise the largest multigene family in many species. However, their expression pattern and localisation remain to be elucidated.

Individual-level variations in malaria susceptibility and acquisition of clinical protection.

After decades of research, our understanding of when and why individuals infected with  develop clinical malaria is still limited. Correlates of immune protection are often sought through prospective cohort studies, where measured host factors are correlated against the incidence of clinical disease over a set period of time. However, robustly inferring individual-level protection from these population-level findings has proved difficult due to small effect sizes and high levels of variance underlying such data.

10-year longitudinal study of malaria in children: Insights into acquisition and maintenance of naturally acquired immunity.

Studies of long-term malaria cohorts have provided essential insights into how interacts with humans, and influences the development of antimalarial immunity. Immunity to malaria is acquired gradually after multiple infections, some of which present with clinical symptoms. However, there is considerable variation in the number of clinical episodes experienced by children of the same age within the same cohort.

Analysis of pir gene expression across the Plasmodium life cycle.

Background: Plasmodium interspersed repeat (pir) is the largest multigene family in the genomes of most Plasmodium species. A variety of functions for the PIR proteins which they encode have been proposed, including antigenic variation, immune evasion, sequestration and rosetting. However, direct evidence for these is lacking.

Determinants of Malaria Protective Immunity in Mice Immunized with Live Sporozoites during Trimethoprim-Sulfamethoxazole Prophylaxis.

HIV and malaria geographically overlap. Trimethoprim-sulfamethoxazole (TMP-SMX) is a drug widely used in HIV-exposed uninfected and infected children in malaria-endemic areas, and is known to have antimalarial effects. Further study in terms of antimalarial impact and effect on development of malaria-specific immunity is therefore essential.

Structure of the -interspersed repeat proteins of the malaria parasite.

The deadly symptoms of malaria occur as parasites replicate within blood cells. Members of several variant surface protein families are expressed on infected blood cell surfaces. Of these, the largest and most ubiquitous are the -interspersed repeat (PIR) proteins, with more than 1,000 variants in some genomes.

Manipulating niche composition limits damage to haematopoietic stem cells during Plasmodium infection.

Severe infections are a major stress on haematopoiesis, where the consequences for haematopoietic stem cells (HSCs) have only recently started to emerge. HSC function critically depends on the integrity of complex bone marrow (BM) niches; however, what role the BM microenvironment plays in mediating the effects of infection on HSCs remains an open question. Here, using a murine model of malaria and combining single-cell RNA sequencing, mathematical modelling, transplantation assays and intravital microscopy, we show that haematopoiesis is reprogrammed upon infection, whereby the HSC compartment turns over substantially faster than at steady-state and HSC function is drastically affected.

Transcriptome analysis of blood and spleen in virulent and avirulent mouse malaria infection.

Malaria is a devastating infectious disease and the immune response is complex and dynamic during a course of a malarial infection. Rodent malaria models allow detailed time-series studies of the host response in multiple organs. Here, we describe two comprehensive datasets containing host transcriptomic data from both the blood and spleen throughout an acute blood stage infection of virulent or avirulent Plasmodium chabaudi infection in C57BL/6 mice.

An enhanced toolkit for the generation of knockout and marker-free fluorescent .

The rodent parasite is an important model of malaria. The ability to produce chronic infections makes it particularly useful for investigating the development of anti- immunity, as well as features associated with parasite virulence during both the acute and chronic phases of infection. also undergoes asexual maturation (schizogony) and erythrocyte invasion in culture, so offers an experimentally-amenable to model for studying gene function and drug activity during parasite replication.

B-cell memory in malaria: Myths and realities.

B-cell and antibody responses to Plasmodium spp., the parasite that causes malaria, are critical for control of parasitemia and associated immunopathology. Antibodies also provide protection to reinfection.

Comparison of whole blood and spleen transcriptional signatures over the course of an experimental malaria infection.

Although the spleen is broadly accepted as the major lymphoid organ involved in generating immune responses to the erythrocytic stages of the malaria parasite, Plasmodium, human splenic tissue is not readily available in most cases. As a result, most studies of malaria in humans rely on peripheral blood to assess cellular immune responses to malaria. The suitability of peripheral blood as a proxy for splenic immune responses is however unknown.

Neutrophil extracellular traps drive inflammatory pathogenesis in malaria.

Neutrophils are essential innate immune cells that extrude chromatin in the form of neutrophil extracellular traps (NETs) when they die. This form of cell death has potent immunostimulatory activity. We show that heme-induced NETs are essential for malaria pathogenesis.

Transcriptional profiling unveils type I and II interferon networks in blood and tissues across diseases.

Understanding how immune challenges elicit different responses is critical for diagnosing and deciphering immune regulation. Using a modular strategy to interpret the complex transcriptional host response in mouse models of infection and inflammation, we show a breadth of immune responses in the lung. Lung immune signatures are dominated by either IFN-γ and IFN-inducible, IL-17-induced neutrophil- or allergy-associated gene expression.

Functional Antibodies against Placental Malaria Parasites Are Variant Dependent and Differ by Geographic Region.

During pregnancy, -infected erythrocytes (IE) accumulate in the intervillous spaces of the placenta by binding to chondroitin sulfate A (CSA) and elicit inflammatory responses that are associated with poor pregnancy outcomes. Primigravidae lack immunity to IE that sequester in the placenta and thus are susceptible to placental malaria (PM). Women become resistant to PM over successive pregnancies as antibodies to placental IE are acquired.

Repeated clinical malaria episodes are associated with modification of the immune system in children.

Background: There are over 200 million reported cases of malaria each year, and most children living in endemic areas will experience multiple episodes of clinical disease before puberty. We set out to understand how frequent clinical malaria, which elicits a strong inflammatory response, affects the immune system and whether these modifications are observable in the absence of detectable parasitaemia.

Methods: We used a multi-dimensional approach comprising whole blood transcriptomic, cellular and plasma cytokine analyses on a cohort of children living with endemic malaria, but uninfected at sampling, who had been under active surveillance for malaria for 8 years.

Publisher Correction: c-Maf controls immune responses by regulating disease-specific gene networks and repressing IL-2 in CD4 T cells.

In the version of this article initially published, the Supplementary Data file was an incorrect version. The correct version is now provided. The error has been corrected in the HTML and PDF version of the article.

Chronic helminth infection does not impair immune response to malaria transmission blocking vaccine Pfs230D1-EPA/Alhydrogel® in mice.

Introduction: Malaria transmission blocking vaccines (TBV) are innovative approaches that aim to induce immunity in humans against Plasmodium during mosquito stage, neutralizing the capacity of the infected vectors to transmit malaria. Pfs230D1-EPA/Alhydrogel®, a promising protein-protein conjugate malaria TBV, is currently being tested in human clinical trials in areas where P. falciparum malaria is coendemic with helminth parasites.

Correction to: Transcriptomes of microglia in experimental cerebral malaria in mice in the presence and absence of Type I Interferon signaling.

Following publication of the original article [1], an error was reported in Table 1. The data repository links in the 4th column were incorrect. In this Correction, the corrected version of Table 1 is shown.