Despite being heavily infiltrated by immune cells, tuberculosis (TB) granulomas often subvert the host response to (Mtb) infection and support bacterial persistence. We previously discovered that human TB granulomas are enriched for immunosuppressive factors typically associated with tumor-immune evasion, raising the intriguing possibility that they promote tolerance to infection. In this study, our goal was to identify the prime drivers for establishing this tolerogenic niche and to determine if the magnitude of this response correlates with bacterial persistence. To do this, we conducted a multimodal spatial analysis of 52 granulomas from 16 non-human primates (NHP) who were infected with low dose Mtb for 9-12 weeks. Notably, each granuloma's bacterial burden was individually quantified allowing us to directly ask how granuloma spatial structure and function relate to infection control. We found that a universal feature of TB granulomas was partitioning of the myeloid core into two distinct metabolic environments, one of which is hypoxic. This hypoxic environment associated with pathologic immune cell states, dysfunctional cellular organization of the granuloma, and a near-complete blockade of lymphocyte infiltration that would be required for a successful host response. The extent of these hypoxia-associated features correlated with worsened bacterial burden. We conclude that hypoxia governs immune cell state and organization within granulomas and is a potent driver of subverted immunity during TB.
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http://dx.doi.org/10.1101/2025.02.18.638923 | DOI Listing |
Front Immunol
March 2025
Department of Pathology, The Eighth Medical Center, General Hospital of the Chinese People's Liberation Army (PLA), Beijing, China.
Background: The early diagnosis and management of lung adenocarcinoma co-existing with tuberculosis (LAC-TB) presents significant challenges in clinical settings. This is compounded by a paucity of robust clinical evidence elucidating the interactions between these two conditions.
Methods: This study included 14 patients diagnosed with LAC-TB, with an equal distribution among those with pulmonary tuberculosis (TB) and those with peripheral lymph node TB.
Arch Intern Med Res
February 2025
Department of Translational Research, College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, California 91766 USA.
Tuberculous meningitis (TBM), the most severe manifestation of extrapulmonary tuberculosis, poses significant global health challenges due to its high mortality rates and complex pathophysiology. This review synthesizes recent findings on TBM, covering epidemiology, pathogenesis, clinical manifestations, diagnostics, and management strategies. TBM disproportionately affects immunocompromised populations, including individuals with HIV, with the highest mortality observed in low-resource settings.
View Article and Find Full Text PDFCurr Protoc
March 2025
Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, New Jersey.
Tuberculosis (TB) remains one of the leading infectious causes of death worldwide. Persistent bacterial populations in specific microenvironments within the host hamper efficient TB chemotherapy. Caseum in the necrotic core of closed granulomas and cavities of pulmonary TB patients can harbor high burdens of drug-tolerant Mycobacterium tuberculosis (MTB) bacilli, making them particularly difficult to sterilize.
View Article and Find Full Text PDFBMJ Open Gastroenterol
March 2025
Gastroenterology and Hepatology Unit, Division of internal Medicine, Faculty of Medicine, Prince of Songkla University, Hat Yai, Thailand
Objective: Granulomatous liver disease (GLD) is a rare condition with various aetiologies and is characterised by the formation of hepatic granulomas. A comprehensive evaluation of GLD from a broad perspective is lacking. We aimed to investigate the aetiology and the clinicoradiopathological characteristics of patients with GLD in recent decades in Thailand.
View Article and Find Full Text PDFFront Cell Infect Microbiol
March 2025
Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, United States.
Like other tuberculous and nontuberculous mycobacterial pathogens of human lung such as and , is likely exposed to a variety of stressors during infection, including hypoxic conditions inside activated macrophages and in the avascular necrotic regions of granulomas. How survives hypoxic stress to establish a chronic infection is currently not well understood. Using RNA-sequencing, we here show that grown under progressive microaerophilic conditions activates more than 4-fold a subset of 16 genes, the expression of 13 of which is dependent on the two-component system regulator DosRS.
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