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Golenbock, D. T.

Publications and source records attributed to Golenbock, D. T..

3 recordsLinked to original sources

Cellular nucleic acid-binding protein (CNBP) dependent cytokine programming shapes host defense against Plasmodium infection

During blood-stage Plasmodium infection, effective immune control hinges on the IL12{beta}-IFN-{gamma} axis, yet how this pathway is transcriptionally tuned in vivo remains incompletely defined. Innate sensing of parasite-derived ligands by pattern-recognition receptors, including Toll like receptors, in dendritic cells and macrophages induces IL-12{beta} production that drives IFN-{gamma} mediated control of infection. Emerging evidence implicates cellular nucleic acid-binding protein (CNBP), a zinc-finger transcriptional regulator, in control of IL12{beta} gene expression in myeloid cells exposed to bacterial and viral infections. Here, we defined the contribution of CNBP in cytokine-driven immunity to Plasmodium infection including both P. falciparum (the major cause of malaria), as well as P. chabaudi and P. berghei ANKA, two rodent species that model human disease. Upon exposure to Plasmodium-infected erythrocytes, CNBP rapidly translocated to the nucleus in mouse and human dendritic cells, bound IL12{beta} promoter, and was required for optimal IL12{beta} induction. Genetic ablation of CNBP in mice and siRNA knockdown of CNBP in human monocyte-derived dendritic cells markedly reduced IL12{beta} production and downstream IFN-{gamma} responses, while TNF- and several other innate cytokines were largely unaffected. In vivo, hematopoietic-specific deletion of CNBP (using vav-iCre; Cnbpfl/fl) resulted in elevated peak parasitemia, impaired parasite clearance, and relapse after initial resolution. Consistent with these outcomes, spleens from mice lacking CNBP in hematopoietic cells exhibited reduced inflammatory remodeling, altered T-cell composition, and transcriptional reprogramming characterized by selective regulation of IL12{beta}-IFN-{gamma} transcripts alongside upregulation of distinct cytotoxic genes. Paradoxically, mice lacking CNBP in hematopoietic cells showed delayed mortality in the lethal infection model, underscoring its context-dependent contributions to host protection and inflammatory pathology. Collectively, these findings position CNBP as a pivotal modulator of the IL12{beta}-IFN-{gamma} axis during malaria, extending its functional repertoire beyond microbial contexts, with potential as a therapeutic target to fine-tune immune responses for enhanced protection with limited immunopathology. Author summaryMalaria remains one of the worlds deadliest infectious diseases, caused by the protozoan Plasmodium that trigger complex immune responses in infected hosts. Effective host defense requires a tightly regulated inflammatory response: too weak and the parasite proliferates unchecked; too strong and the host suffers harmful immunopathology. Central to this balance is the IL12{beta}-IFN-{gamma} signaling axis. In this study, we investigated the role of a transcriptional regulator, known as Cellular Nucleic acid-Binding Protein (CNBP), in shaping the immune response against the Plasmodium parasite. We found that CNBP rapidly responds to parasite exposure, translocates to the nucleus and drives IL12{beta} production in innate immune cells, and promotes downstream IFN-{gamma} driven adaptive immune responses. Mice lacking CNBP in hematopoietic stem cells exhibited changes in transcription of key inflammatory genes; markedly reduced systemic IL12{beta} and IFN-{gamma}, leading to significantly elevated peripheral blood parasitemia and altered immune cell composition. Paradoxically, the absence of CNBP delayed mortality in a lethal infection model and reduced inflammatory responses that are associated with cytokine storm-mediated immunopathology. These findings identify CNBP as a key regulator that fine-tunes protective immunity and inflammatory pathology during malaria, highlighting its potential as a therapeutic target to optimize host defense while limiting harmful inflammation.

immunology↗

Development of a high-throughput, quantitative platform using human cerebral organoids to study virus-induced neuroinflammation in Alzheimer's disease

Neuroinflammation is a central process in the pathogenesis of several neurodegenerative diseases such as Alzheimers disease (AD), and there are active efforts to target pathways involved in neuroinflammation for molecular biomarker discovery and therapeutic development in neurodegenerative diseases. It was also proposed that there may be an infectious etiology in AD that is associated with viruses such as herpes simplex virus (HSV-1) and influenza A virus (IAV), leading to neuroinflammation-induced AD pathogenesis or disease progression. We sought to develop high-throughput, quantitative molecular biomarker assays using dissociated cells from human cerebral organoids (dcOrgs), that can used for screening compounds to reverse AD-associated neuroinflammation. We found that HSV-1 infection, but not IAV infection, in dcOrgs led to increased intracellular A{beta}42 and phosphorylated Tau-Thr212 (pTau-212) expression, lower ratios of secreted A{beta}42/40, as well as neuronal loss, and increased proportions of astrocytes and microglia, which are hallmarks of AD. Among the glia cell-type markers, Iba1 (microglia) and GFAP (astrocyte) expression were most strongly correlated with HSV-1 expression, which further supported that these biomarkers are perturbed by glia-mediated neuroinflammation. By performing large-scale RNA sequencing, we observed that differentially expressed transcripts in HSV-1 infected dcOrgs were specifically enriched for AD-associated GWAS genes, but not for genes associated with other common neurodegenerative, neuropsychiatric or autoimmune diseases. Immediate treatment of HSV-1 infected dcOrgs with anti-herpetic drug acyclovir (ACV) rescued most of the cellular and transcriptomic biomarkers in a dosage-dependent manner, indicating that it is possible to use our high-throughput platform to identify compounds or target genes that can reverse these neuroinflammation-induced biomarkers associated with AD.

genomics↗

Epigenetic regulation of innate immune genes and enhanced interleukin-10 expression underlie chronic subclinical Plasmodium chabaudi infection

Subclinical (asymptomatic) parasitemia is very common amongst Plasmodium-infected individuals. The immunological mechanisms underlying subclinical parasitemia remain elusive. We investigated the immune regulatory mechanisms behind chronic asymptomatic Plasmodium infection using mice lacking humoral immunity ({micro}MT-/- mice). {micro}MT-/- mice became chronically infected, despite lacking outward signs of disease, and exhibited increased macrophage numbers, decreased dendritic and CD4 cells, massive hemozoin accumulation in the spleen and bone marrow, and inadequate hematopoiesis. These changes were accompanied by high circulating levels of interleukin-10 (IL-10), enhanced chromatin accessibility of the STAT3 promoter, and enhanced STAT3 binding to the IL-10 promoter in macrophages. Inhibition of IL-10 signaling, despite promoting parasite clearance, resulted in a proinflammatory response, weight loss, and mortality. These results suggest that epigenetic changes induced by chronic P. chabaudi infection lead to high levels of circulating IL-10, protecting chronically infected mice against an excessive inflammatory response to high levels of blood-stage parasites. Author summaryMalaria is a life-threatening disease with a range of symptoms, and it is induced in humans by infections with different species of Plasmodium. Highly prevalent in endemic regions, asymptomatic Plasmodium infections are related to long-term exposure to the parasite due to multiple infections and have been demonstrated in human and mouse studies to be associated with elevated levels of IL-10. However, how IL-10 levels remain elevated in the circulation in individuals over the long term has not been determined. We used a mouse model of chronic asymptomatic Plasmodium infection to investigate the mechanisms by which IL-10 levels are elevated during chronic asymptomatic infection. Our results show that epigenetic changes in immune genes of myeloid origin could be responsible for the elevated levels of IL-10, and that IL-10 signaling protected chronically infected mice from a severe inflammatory response induced by the infection.

immunology↗