Product Citations: 44

α-Synuclein fibrils enhance HIV-1 infection of human T cells, macrophages and microglia.

In Nature Communications on 18 January 2025 by Olari, L. R., Liu, S., et al.

HIV-associated neurocognitive disorders (HAND) and viral reservoirs in the brain remain a significant challenge. Despite their importance, the mechanisms allowing HIV-1 entry and replication in the central nervous system (CNS) are poorly understood. Here, we show that α-synuclein and (to a lesser extent) Aβ fibrils associated with neurological diseases enhance HIV-1 entry and replication in human T cells, macrophages, and microglia. Additionally, an HIV-1 Env-derived amyloidogenic peptide accelerated amyloid formation by α-synuclein and Aβ peptides. Mechanistic studies show that α-synuclein and Aβ fibrils interact with HIV-1 particles and promote virion attachment and fusion with target cells. Despite an overall negative surface charge, these fibrils facilitate interactions between viral and cellular membranes. The enhancing effects of human brain extracts on HIV-1 infection correlated with their binding to Thioflavin T, a dye commonly used to stain amyloids. Our results suggest a detrimental interplay between HIV-1 and brain amyloids that may contribute to the development of neurodegenerative diseases.
© 2025. The Author(s).

  • Immunology and Microbiology
  • Neuroscience

Neural crest cells (NCCs) are cell populations that originate during the formation of neural crest in developmental stages. They are characterized by their multipotency, self-renewal and migration potential. Given their ability to differentiate into various types of cells such as neurons and Schwann cells, NCCs hold promise for cell therapy applications. The conventional method for obtaining NCCs involves inducing them from stem cells like induced pluripotent stem cells (iPSCs), followed by a long-term passage or purification using fluorescence-activated cell sorting (FACS). Although FACS allows high purity induced neural crest cells (iNCCs) to be obtained quickly, it is complex and costly. Therefore, there is a need for a simpler, cost-effective and less time-consuming method for cell therapy application.
To select differentiated iNCCs from heterogeneous cell populations quickly without using FACS, we adopted the use of scaffold material full-length laminin 211 (LN211), a recombinant, xeno-free protein suitable for cell therapy. After fist passage on LN211, iNCCs characterization was performed using polymerase chain reaction and flow cytometry. Additionally, proliferation and multipotency to various cells were evaluated.
The iNCCs obtained using our new method expressed cranial NCC- related genes and exhibited stable proliferation ability for at least 57 days, while maintaining high expression level of the NCCs marker CD271. They demonstrated differentiation ability into several cell types: neurons, astrocytes, melanocytes, smooth muscle cells, osteoblasts, adipocytes and chondrocytes. Furthermore, they could be induced to differentiate into induced mesenchymal stem cells (iMSCs) which retain the essential functions of somatic MSCs.
In this study, we have developed novel method for obtaining high purity iNCCs differentiated from iPSCs in a short time using LN211 under xeno-free condition. Compared with traditional methods, like FACS or long-term passage, this approach enables the acquisition of a large amount of cells at a lower cost and labor, and it is expected to contribute to stable supply of large scale iNCCs for future cell therapy applications.
© 2024 The Author(s).

  • Stem Cells and Developmental Biology

EP300-ZNF384 transactivates IL3RA to promote the progression of B-cell acute lymphoblastic leukemia.

In Cell Communication and Signaling : CCS on 2 April 2024 by Hou, Z., Ren, Y., et al.

The EP300-ZNF384 fusion gene is an oncogenic driver in B-cell acute lymphoblastic leukemia (B-ALL). In the present study, we demonstrated that EP300-ZNF384 substantially induces the transcription of IL3RA and the expression of IL3Rα (CD123) on B-ALL cell membranes. Interleukin 3 (IL-3) supplementation promotes the proliferation of EP300-ZNF348-positive B-ALL cells by activating STAT5. Conditional knockdown of IL3RA in EP300-ZF384-positive cells inhibited the proliferation in vitro, and induced a significant increase in overall survival of mice, which is attributed to impaired propagation ability of leukemia cells. Mechanistically, the EP300-ZNF384 fusion protein transactivates the promoter activity of IL3RA by binding to an A-rich sequence localized at -222/-234 of IL3RA. Furthermore, forced EP300-ZNF384 expression induces the expression of IL3Rα on cell membranes and the secretion of IL-3 in CD19-positive B precursor cells derived from healthy individuals. Doxorubicin displayed a selective killing of EP300-ZNF384-positive B-ALL cells in vitro and in vivo. Collectively, we identify IL3RA as a direct downstream target of EP300-ZNF384, suggesting CD123 is a potent biomarker for EP300-ZNF384-driven B-ALL. Targeting CD123 may be a novel therapeutic approach to EP300-ZNF384-positive patients, alternative or, more likely, complementary to standard chemotherapy regimen in clinical setting.
© 2024. The Author(s).

  • Cancer Research
  • Endocrinology and Physiology
  • Immunology and Microbiology

Mycobacterium tuberculosisexploits SIRT2 for iron acquisition to facilitate its intracellular survival

Preprint on BioRxiv : the Preprint Server for Biology on 7 January 2024 by Talukdar, S., Modanwal, R., et al.

Iron availability is a critical factor for both bacteria and humans, and its availability significantly influences host-pathogen dynamics. As Mtb has coevolved with the human race, Mtb relentlessly tries to exploit iron from the tightly regulated iron machinery of host. Sirtuins are evolutionary conserved NAD + -dependent deacetylases involved in various cellular processes including infection. Notably, the cytosolic protein, Sirtuin 2 regulates cellular iron homeostasis in hepatocytes and after Mtb infection, SIRT2 translocates to the nucleus leading to decreased protective immune response. However, the underlying mechanism as to how Mtb exploits SIRT2 for iron acquisition remains unknown. In the current study, we observe that the decreased bacillary load in SIRT2 inhibited or knock down cells is due to low availability of iron to the bacilli. Inhibition or knockdown of SIRT2 in Mtb infected cells displays differential modulation of iron import and export proteins suggesting ongoing tussle by host to limit the bioavailability of iron to pathogen. More specifically, by flow cytometry analysis, we show significant upregulation of cell surface Apo Tf and GAPDH in infected SIRT2 inhibited macrophages. Thus, in SIRT2 depleted state, we delineate a different mechanism of iron export occurring through Apo Tf and GAPDH during infection in contrast to the classical iron exporter Fpn1. Collectively, our findings showed the importance of SIRT2-mediated iron regulation in Mtb pathogenesis and can encourage designing of novel host-targeted therapeutics.

Stromal heterogeneity may explain increased incidence of metaplastic breast cancer in women of African descent.

In Nature Communications on 14 September 2023 by Kumar, B., Khatpe, A. S., et al.

The biologic basis of genetic ancestry-dependent variability in disease incidence and outcome is just beginning to be explored. We recently reported enrichment of a population of ZEB1-expressing cells located adjacent to ductal epithelial cells in normal breasts of women of African ancestry compared to those of European ancestry. In this study, we demonstrate that these cells have properties of fibroadipogenic/mesenchymal stromal cells that express PROCR and PDGFRα and transdifferentiate into adipogenic and osteogenic lineages. PROCR + /ZEB1 + /PDGFRα+ (PZP) cells are enriched in normal breast tissues of women of African compared to European ancestry. PZP: epithelial cell communication results in luminal epithelial cells acquiring basal cell characteristics and IL-6-dependent increase in STAT3 phosphorylation. Furthermore, level of phospho-STAT3 is higher in normal and cancerous breast tissues of women of African ancestry. PZP cells transformed with HRasG12V ± SV40-T/t antigens generate metaplastic carcinoma suggesting that these cells are one of the cells-of-origin of metaplastic breast cancers.
© 2023. Springer Nature Limited.

  • Cancer Research
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