Human liver organoids are susceptible to Plasmodium vivax infection.

Background: The eradication of Plasmodium vivax malaria is complicated due to the presence of hypnozoites, the hidden dormant form of the parasite that is present in the liver. Currently available drug regimens are effective at killing hypnozoites but cause side effects and are difficult to administer. Studies testing drugs for liver-stage malaria remain rare and mainly rely on the use of cancerous or immortalized hepatic cells and primary hepatocytes.

Modelling amoebic brain infection caused by Balamuthia mandrillaris using a human cerebral organoid.

The lack of disease models adequately resembling human tissue has hindered our understanding of amoebic brain infection. Three-dimensional structured organoids provide a microenvironment similar to human tissue. This study demonstrates the use of cerebral organoids to model a rare brain infection caused by the highly lethal amoeba Balamuthia mandrillaris.

Improving hematopoietic differentiation from human induced pluripotent stem cells by the modulation of Hippo signaling with a diarylheptanoid derivative.

Background: The diarylheptanoid ASPP 049 has improved the quality of adult hematopoietic stem cell (HSC) expansion ex vivo through long-term reconstitution in animal models. However, its effect on hematopoietic regeneration from human induced pluripotent stem cells (hiPSCs) is unknown.

Method: We utilized a defined cocktail of cytokines without serum or feeder followed by the supplementation of ASPP 049 to produce hematopoietic stem/progenitor cells (HSPCs).

Trio fluorophore-based phenotypic assay for the detection of artemisinin-induced growth-arrested Plasmodium falciparum in human erythrocytes.

Artemisinin combination therapy remains effective for the treatment of falciparum malaria. However, Plasmodium falciparum can escape the effects of artemisinin by arresting their growth. The growth-arrested parasites cannot be distinguished from nonviable parasites with standard microscopy techniques due to their morphological similarities.

Thrombopoietin-independent generation of platelet-like particles from megakaryoblastic cells.

The use of megakaryoblastic leukemia MEG-01 cells can help reveal the mechanisms of thrombopoiesis. However, conventional in vitro activation of platelet release from MEG-01 cells requires thrombopoietin, which is costly. Here, we aim to develop a more straightforward and affordable method.

Phenotypic assay for cytotoxicity assessment of against human neurospheroids.

Introduction: The phenotypic screening of drugs against , a neuropathogenic amoeba, involves two simultaneous phases: an initial step to test amoebicidal activity followed by an assay for cytotoxicity to host cells. The emergence of three-dimensional (3D) cell cultures has provided a more physiologically relevant model than traditional 2D cell culture for studying the pathogenicity of . However, the measurement of ATP, a critical indicator of cell viability, is complicated by the overgrowth of in coculture with host cells during drug screening, making it challenging to differentiate between amoebicidal activity and drug toxicity to human cells.

Mitochondrial genome diversity of revealed by a fatal case of granulomatous amoebic encephalitis.

Introduction: () is a free-living amoeba that can cause rare yet fatal granulomatous amoebic encephalitis (GAE). However, efficacious treatment for GAE is currently unavailable, especially when genomic studies on are limited.

Methods: In this study, strain KM-20 was isolated from the brain tissue of a GAE patient, and its mitochondrial genome was assembled using high-coverage Nanopore long reads and Illumina short reads.

Glucose-6-phosphate dehydrogenase is dispensable for human erythroid cell differentiation in vitro.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency impairs cellular processes under oxidative stress. Individuals with severe G6PD deficiency still produce sufficient numbers of erythrocytes. Nevertheless, the G6PD independence of erythropoiesis remains questionable.

An Optical and Chemiluminescence Assay for Assessing the Cytotoxicity of against Human Neurospheroids.

A spheroid is a cell aggregate in a three-dimensional context; thereby, it recapitulates the cellular architecture in human tissue. However, the utility of spheroids as an assay for host-parasite interactions remains unexplored. This study demonstrates the potential use of neurospheroids for assessing the cytotoxicity of the life-threatening pathogenic amoeba .

Balamuthia mandrillaris trophozoites ingest human neuronal cells via a trogocytosis-independent mechanism.

Background: Environmental protozoa need an adaptation mechanism to survive drastic changes in niches in the human body. In the brain parenchyma, Balamuthia mandrillaris trophozoites, which are causative agents of fatal brain damage, must acquire nutrients through the ingestion of surrounding cells. However, the mechanism deployed by the trophozoites for cellular uptake remains unknown.

Peptide of Infective Larval Extract That Harnesses Growth of Human Hepatoma Cells.

, a tissue-dwelling helminth, causes human trichinellosis through ingestion of undercooked meat containing the parasite's infective larvae. However, benefits from infection have been documented: reduction of allergic diseases, inhibition of collagen-induced arthritis, delay of type 1 diabetes progression, and suppression of cancer cell proliferation. Since conventional cancer treatments have limited and unreliable efficacies with adverse side effects, novel adjunctive therapeutic agents and strategies are needed to enhance the overall treatment outcomes.

Impairment of Invasion and Maturation and Decreased Selectivity of Plasmodium falciparum in G6PD Viangchan and Mahidol Variants.

Background: Protection against Plasmodium falciparum is observed in a population deficient in glucose-6-phosphate dehydrogenase (G6PD), particularly in African and Mediterranean regions. However, such protection remains unknown among G6PD-deficient individuals in Southeast Asia.

Methods: In this study, we assessed the invasion and maturation of P falciparum K1 in a culture of erythrocytes isolated from Thai subjects carrying Viangchan (871G > A) and Mahidol (487G > A).

Next-Generation Human Liver Models for Antimalarial Drug Assays.

Advances in malaria prevention and treatment have significantly reduced the related morbidity and mortality worldwide, however, malaria continues to be a major threat to global public health. Because parasites reside in the liver prior to the appearance of clinical manifestations caused by intraerythrocytic development, the liver stage represents a vulnerable therapeutic target to prevent progression. Currently, a small number of drugs targeting liver-stage parasites are available, but all cause lethal side effects in glucose-6-phosphate dehydrogenase-deficient individuals, emphasizing the necessity for new drug development.

Progress and challenges in the use of fluorescence-based flow cytometric assays for anti-malarial drug susceptibility tests.

Drug-resistant Plasmodium is a frequent global threat in malaria eradication programmes, highlighting the need for new anti-malarial drugs and efficient detection of treatment failure. Plasmodium falciparum culture is essential in drug discovery and resistance surveillance. Microscopy of Giemsa-stained erythrocytes is common for determining anti-malarial effects on the intraerythrocytic development of cultured Plasmodium parasites.

Molecular identification of native Wolbachia pipientis in Anopheles minimus in a low-malaria transmission area of Umphang Valley along the Thailand-Myanmar border.

Background: Wolbachia, obligate intracellular bacteria, infect the majority of arthropods, including many mosquito species of medical importance. Some Wolbachia strains interfere with the development of Plasmodium parasites in female Anopheles, a major vector of malaria. The use of Wolbachia as a means to block malaria transmission is an emerging vector control strategy in highly endemic areas.

Generation of human liver organoids from pluripotent stem cell-derived hepatic endoderms.

Background: The use of a personalized liver organoid derived from human-induced pluripotent stem cells (HuiPSCs) is advancing the use of in vitro disease models for the design of specific, effective therapies for individuals. Collecting patient peripheral blood cells for HuiPSC generation is preferable because it is less invasive; however, the capability of blood cell-derived HuiPSCs for hepatic differentiation and liver organoid formation remains uncertain. Moreover, the currently available methods for liver organoid formation require a multistep process of cell differentiation or a combination of hepatic endodermal, endothelial and mesenchymal cells, which is a major hurdle for the application of personalized liver organoids in high-throughput testing of drug toxicity and safety.

Paracrine CCL17 and CCL22 signaling regulates hematopoietic stem/progenitor cell migration and retention in mouse fetal liver.

Fetal liver (FL) is the major embryonic hematopoietic organ and a site where circulating hematopoietic stem/progenitor cells (HSPCs) reside. However, HSPC migration/retention mechanisms in FL remain unclear. A chemokine screen revealed that the CCR4 ligands CCL17 and CCL22 are highly expressed in mouse embryonic day (E) 12.

A simple monochromatic flow cytometric assay for assessment of intraerythrocytic development of Plasmodium falciparum.

Background: Gold standard microscopic examination of Plasmodium falciparum intraerythrocytic stage remains an important process for staging and enumerating parasitized erythrocytes in culture; however, microscopy is laborious and its accuracy is dependent upon the skill of the examiner.

Methods: In this study, ViSafe Green (VSG), which is a nucleic acid-binding fluorescent dye, was used for assessing in vitro development of P. falciparum using flow cytometry.

Twist1 regulates embryonic hematopoietic differentiation through binding to and promoter regions.

Mechanisms underlying differentiation of embryonic hematopoietic stem/progenitor cells (HSPCs) remain unclear. In mouse, intra-aortic clusters (IACs) form in the aorta-gonad-mesonephros region and acquire HSPC potential after 9.5 days postcoitum (dpc).

Purification of zebrafish erythrocytes as a means of identifying a novel regulator of haematopoiesis.

Zebrafish embryos are useful to study haematopoietic gene function in vertebrates, although lack of antibodies to zebrafish proteins has limited the purification of specific cell populations. Here, we purified primitive zebrafish erythrocytes using 1, 5-bis{[2-(di-methylamino)ethyl]amino}-4, 8-dihydroxyanthracene-9, 10-dione (DRAQ5 ), a DNA-staining fluorescent dye. At 48-h post-fertilization, we sorted small-sized cells from embryos using forward scatter and found that they consisted of DRAQ5 and DRAQ5 populations.