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Wong, K.-W.

Publications and source records attributed to Wong, K.-W..

4 recordsLinked to original sources

Rapid GPR183-mediated recruitment of eosinophils to the lung after Mycobacterium tuberculosis infection

Influx of eosinophils into the lungs is typically associated with type-II responses during allergy, fungal and parasitic infections. However, we previously reported that eosinophils accumulate in lung lesions during type-I inflammatory responses to Mycobacterium tuberculosis (Mtb) in humans, macaques, and mice where they contribute to host resistance. Here we show eosinophils migrate into the lungs of macaques and mice as early as one week after Mtb-exposure. In mice this influx was CCR3 independent and instead required cell-intrinsic expression of the oxysterol-receptor GPR183, which is highly expressed on human and macaque eosinophils. Murine eosinophils interacted directly with bacilli-laden alveolar macrophages, which upregulated the oxysterol-synthesizing enzyme Ch25h, and eosinophil recruitment was impaired in Ch25h deficient mice. Our findings show that eosinophils are among the first cells from circulation to sense and respond to Mtb infection of alveolar macrophages and reveal a novel role for GPR183 in the migration of eosinophils into lung tissue. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/480919v1_ufig1.gif" ALT="Figure 1"> View larger version (105K): org.highwire.dtl.DTLVardef@e8cd29org.highwire.dtl.DTLVardef@1f5769borg.highwire.dtl.DTLVardef@3dce9borg.highwire.dtl.DTLVardef@1c75587_HPS_FORMAT_FIGEXP M_FIG C_FIG HIGHLIGHTSIn mice and macaques eosinophils accumulate early in Mtb-infected lungs preceding neutrophils Eosinophils interact with Mtb-infected cells in the alveoli in mice Early pulmonary eosinophil migration occurs independently of CCR3 in mice Early lung migration in mice requires Ch25h and eosinophil-intrinsic GPR183 expression

immunology↗

Eosinophils are an integral component of the pulmonary granulocyte response in Tuberculosis and promote host resistance in mice

Host resistance to Mycobacterium tuberculosis infection requires the activities of multiple leukocyte subsets, yet the roles of the different innate effector cells during tuberculosis are incompletely understood. Here we uncover an unexpected association between eosinophils and Mtb infection. In humans, eosinophils are decreased in the blood but enriched in resected human tuberculosis lung lesions and autopsy granulomas. Influx of eosinophils is also evident in infected zebrafish, mice, and nonhuman primate granulomas, where they are functionally activated and degranulate. Importantly, employing complementary genetic models of eosinophil deficiency, we demonstrate that, in mice, eosinophils are required for optimal pulmonary bacterial control and host survival after Mtb infection. Collectively, our findings uncover an unexpected recruitment of eosinophils to the infected lung tissue and a protective role for these cells in the control of Mtb infection in mice.

immunology↗

Immune deposit and vasculopathy in metabolic-active lung tissues of patients with pulmonary tuberculosis

Metabolic activity in pulmonary lesion is associated with disease severity and relapse risk in tuberculosis. However, the nature of the metabolic activity associated with tuberculosis in humans remains unclear. Previous works indicate that tuberculosis bears resemblance transcriptionally with systemic lupus erythematosus in peripheral blood, except that the plasma cell component was absent in tuberculosis. Here we reported that the missing transcriptional component was present within the metabolic active tissues in the lung of patients with sputum culture-negative tuberculosis, within which increased levels of circulating immune complexes and anti-dsDNA antibodies were found relative to nearby non-metabolic active tissues. Histological examination revealed specific vascular deposition of immune complexes, neutrophil extracellular traps, and vascular necrosis in the metabolic-active tissue. Thus, tuberculosis-initiated metabolic activity was associated with hyperactive antibody responses and vascular pathology, and shared features with systemic lupus erythematosus and other autoimmune diseases. We discussed these observations in the context of earlier literatures demonstrating that similar effects could be induced in humans and animal models by complete freunds adjuvant, the most potent antibody response inducer ever reported. Our small case series, if verified in a larger size study, might help inform host-directed therapies to alleviate disease progression and augment treatment efficacy. IMPORTANCEIn patients with pulmonary tuberculosis, lung tissues were destroyed by a hyperactive inflammatory response towards M. tuberculosis. The mechanisms underlying the inflammatory response are still poorly understood. Using 18F-FDG avidity as a surrogate marker of inflammation, we have identified that hyper-inflamed tissues possessed features associated with systemic lupus erythematosus: gene expression signatures of plasma cell and immunoglobulins and increased levels of anti-dsDNA antibodies, immune deposits, and vasculopathy. This observation might suggest an explanation to why patients with tuberculosis share more gene expression signatures with autoimmune diseases than infectious diseases and why they are more likely to develop autoimmune diseases. Defining the inflammatory responses at the lesion could help inform host-directed therapies to intervene disease progression or even accelerate cure.

immunology↗

Dynamic ubiquitination determines transcriptional activity of the plant immune coactivator NPR1

Activation of systemic acquired resistance in plants is associated with transcriptome reprogramming induced by the unstable coactivator NPR1. Immune-induced ubiquitination and proteasomal degradation of NPR1 are thought to facilitate continuous delivery of active NPR1 to target promoters, thereby maximising gene expression. Because of this potentially costly sacrificial process, we investigated if ubiquitination of NPR1 plays transcriptional roles prior to its proteasomal turnover. Here we show ubiquitination of NPR1 is a processive event in which initial modification by a Cullin-RING E3 ligase promotes its chromatin association and expression of target genes. Only when polyubiquitination of NPR1 is enhanced by the E4 ligase, UBE4, it is targeted for proteasomal degradation. Conversely, ubiquitin ligase activities are opposed by UBP6/7, two proteasome-associated deubiquitinases that enhance NPR1 longevity. Thus, immune-induced transcriptome reprogramming requires sequential actions of E3 and E4 ligases balanced by opposing deubiquitinases that fine-tune activity of NPR1 without strict requirement for its sacrificial turnover.

plant biology↗