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Slawinski, H.

Publications and source records attributed to Slawinski, H..

8 recordsLinked to original sources

Contribution of cytotoxic CD8 T cells, neutrophils and type 1 interferon signaling to hyperinflammatory pathology in HIV associated TB meningitis

Immune dysregulation contributes to death and disability in tuberculous meningitis. People living with HIV have the least evidence that anti-inflammatory therapy improves the poor outcome. Improving therapy relies on a more refined understanding of the host immune response. Single-cell RNA sequencing of 188,983 CSF cells from 25 adults with HIV-associated TBM revealed a predominance of cytotoxic CD8 T cells with low cytokine expression. In microbiologically-confirmed TBM, there was greater cytotoxicity in T, NK and {gamma}{delta} cells, and higher type 1 interferon stimulation in T and B lymphocytes. Neutrophils expressed markers suggesting heightened cytokine stimulation, enhanced effector function, and IL-8-mediated neutrophil recruitment. In a longitudinal cohort, type 1 interferon signaling increased in blood and CSF following treatment initiation. Overall, findings indicate a hyper-inflammatory immune response in the CSF of HIV-associated TBM patients characterised by an accumulation of granzyme-rich cytotoxic CD8 T cells, highly activated neutrophils and host-detrimental type 1 interferon signaling.

immunology↗

Immune signatures of protection and progression in the airways of recent human tuberculosis household contacts

Whilst the majority of individuals infected with M. tuberculosis control the infection and remain asymptomatic, only 5-10% progress to active tuberculosis (TB)1. Previous or current infection with M. tuberculosis is detected using antigen-specific interferon (IFN)-{gamma} release assays (IGRA), which cannot identify those who will remain healthy or progress to active TB1. However, 18F-Fluorodeoxyglucose positron emission-computed tomography (PET-CT) can detect increased immune cell metabolic activity in lung parenchyma and intrathoracic lymph nodes associated with infection2. The local early immune factors dictating protection or disease progression have not been defined. To address this, we interrogated the airway immune response at single cell resolution in bronchoalveolar lavage (BAL) from extensively clinically characterised recent household contacts of TB patients, who either controlled the infection or progressed to TB disease. Using unbiased analysis of bulk and scRNA-seq of BAL samples, we define type I IFN-dependent and -independent neutrophil signatures in active TB patients and contacts that progressed to TB. We additionally report an inverse relationship between airway neutrophils and T cells, with T cells showing signatures of exhaustion, cytotoxicity and cell death in progressors and TB patients with a neutrophil dominated airway profile. Conversely, T cell signatures of protection in contacts who remained healthy were dominated by genes related to regulation, quiescence and a stem-like profile. We show that both the inflammatory neutrophil signature of TB progression and the stem-like T cell signature of non-progressors from human airways were recapitulated in scRNA-seq data from non-human primate (NHP) granulomas, associated with disease or immune protection, respectively. Our findings from early human airway responses in TB contacts reveal genes, pathways and cell states that may dictate infection outcome and inform strategies for host-directed therapy and vaccine studies.

immunology↗

Hallmarks of adaptive immunity in a metastatic clear cell renal cell carcinoma (ccRCC) long-term elite survivor

Clear cell renal cell carcinoma (ccRCC) presents with metastatic disease in nearly one-third of patients, with a 5-year survival of only [~]10%. Although anti-angiogenic therapies and immune checkpoint inhibitors (ICIs) have improved outcomes, therapeutic resistance and immune-related adverse events limit durable responses. Exceptional long-term survivors provide a unique opportunity to uncover mechanisms of sustained anti-tumour immunity and guide therapeutic strategies. Here, we present a spatial and temporal dissection of adaptive immunity in an extraordinary 16-year ccRCC survivor, integrating single-cell sequencing, multiplex immunofluorescence, B and T cell receptor (BCR/TCR) repertoire analysis, and antibody profiling. We reveal persistent and spatially coordinated B and T cell clones over 16 years, indicating long-term immune memory and surveillance throughout tumour evolution. B cell analysis identified pronounced clonal expansions involving intrinsically autoreactive IGHV4-34 B cells undergoing ongoing germinal centre (GC) maturation in tumour-draining lymph nodes (dLNs) and spleen. These clones progressively lost autoreactivity while acquiring tumour-specificity through somatic hypermutation (SHM), consistent with clonal redemption. Redeemed B cells displayed enhanced antigen-presenting functions and localised to tertiary lymphoid structures (TLS), where they interacted with CD8 T cells, as inferred from doublet analysis. In parallel, persistent CD8+ effector T cell clones highlighted the contribution of long-lived lymphocytes to tumour control. Comparison of the primary tumour and pancreatic metastatic with paired tumour-free dLNs showed that TLS mirrored GC functionality, particularly for PD-1+ CD8+ T cells, while TLS maturation was stroma-dependent and impaired at the metastatic site. Finally, tumour-derived BCRs revealed antibody binding to tumour specific "public" antigens without cross-reactivity to normal tissue. Together, these findings establish clonal persistence, TLS engagement, and coordinated B-T cell immune surveillance as hallmarks of durable tumour control, providing a framework for next-generation antibody therapeutics and patient stratification in metastatic ccRCC. What is already known on this topic.Tertiary lymphoid structures within the tumour microenvironment (TME) and clonal expansions of CD8+ T cells are associated with better survival and improved response to immunotherapies in ccRCC. However, identifying markers of prolonged survival is challenging due to the rarity of long-term survivors (LTS), and the predominance of studies focused on T cell immunity, leaving B cell contribution almost unexplored. What this study adds.This study provides an integrated analysis of B and T cell responses in an exceptional 16-year LTS with metastatic ccRCC, revealing key immunologic features of sustained anti-tumour immunity. Beyond T cell dynamics, it highlights the multifaceted role of B cells as antigen presenting cells, antibody producers, and modulators of CD8+ T cell effector functions through direct interactions within TLS. Importantly, it reveals potential tumour-specific antigens driving humoral responses. How this study might affect research, practice or policy.By uncovering mechanisms of sustained tumour control, this work establishes a framework for identifying adaptive immune biomarkers of long-term survival and refining patient stratification in metastatic ccRCC. Multimodal assessment of B cell specificity and spatial interactions between re-educated B cells and CD8+ T cells within TLS introduces a new paradigm for understanding coordinated B and T cell responses. These insights have direct implications for antibody-based drug discovery and development of immunotherapies that harness the B-T cell axis.

cancer biology↗

Blimp-1 and c-Maf regulate common and unique gene networks to protect against distinct pathways of pathobiont-induced colitis

Intestinal immune responses to commensals and pathogens are controlled by IL-10 to avoid intestinal immune pathology. We show that the transcription factors Blimp-1 (Prdm-1) and c-Maf are co-dominant regulators of Il10 in Foxp3+ regulatory T cells, but also negatively regulate proinflammatory cytokines in effector T cells. Mice with T cell-specific deletion of Prdm-1, Maf or the combination of both transcription factors did not develop inflammatory intestinal pathologies at the steady state. Double deficient Prdm1fl/flMaffl/flCd4Cre mice infected with Helicobacter hepaticus developed severe colitis with a major increase in TH1/NK/ILC1 effector genes in lamina propria leucocytes (LPLs), while Prdm1fl/flCd4Cre and Maffl/flCd4Cre mice showed mild/moderate pathology and a less-marked Type I effector response. LPLs from infected Maffl/flCd4Cre mice showed increased Il17a expression and an accompanying increase in granulocytes and myeloid cells, which was less marked in Prdm1fl/flMaffl/flCd4Cre mice, with increased T cell-myeloid-neutrophil interactions inferred from scRNA-seq analysis and confirmed by immunofluorescent analysis of colon sections. Genes over-expressed in human IBD showed differential expression in the LPL from infected mice in the absence of Prdm1 or Maf, revealing potential pathobiologic mechanisms of human disease.

immunology↗

Single-cell immune multi-omics and repertoire analyses in pancreatic ductal adenocarcinoma reveal differential immunosuppressive mechanisms within different tumour microenvironments

Pancreatic ductal adenocarcinoma (PDAC) has an extremely poor prognosis. Understanding the multiple mechanisms by which the tumour evades immune control, and how these mechanisms may be disrupted is critical to developing targeted immunotherapies. Previous studies have shown that higher lymphocyte infiltration is associated with better survival, and here we investigated what mediates these differences. We performed a comprehensive analysis of PDAC-associated immune cells using single cell multi-omics coupled with re-analysis of public PDAC scRNA-seq datasets. We introduce novel single-cell and repertoire analyses that have uncoupled diverse roles and contributions of various immune cell populations within different tumour microenvironments (TMEs). They revealed clear distinctions in the clonal characteristics among different patient groups, provided valuable insights into the mechanisms of immune cell migration and tissue adaptation underlying these disparities. These results point to differential CD4 polarisation of intra-tumoural T cells, differential B cell differentiation, GC reactions, antigen presentation pathways, and distinct cell-cell communication between the myeloid-enriched and adaptive-enriched groups. Overall, we identified two major distinct themes for future immune intervention within PDAC patients between those with higher adaptive versus myeloid immune cell infiltration.

immunology↗

HLA class II mediates type 1 diabetes risk by anti-insulin repertoire selection

Type 1 diabetes (T1D) is a common autoimmune disorder characterized by the destruction of insulin-secreting pancreatic {beta} cells [1], in which polymorphism of the human leukocyte antigen (HLA) class II region is the major genetic risk factor [2, 3, 4]. However, how variation in class II molecules alters T1D risk remains a longstanding question. Here we show how T1D risk due to HLA class II haplotype combinations [5] correlates with the frequency of negatively charged sequences in the CDR3{beta} region of CD4+ T cell receptor (TCR) repertoires purified from peripheral blood. These sequences are known to be common in receptors that bind insulin B:9-23 [6], the primary autoantigen in T1D. We also show the same effect in circulating activated CD4+ T cells from newly-diagnosed T1D cases, and in islet-infiltrating T cells from patients with active T1D. Furthermore, we demonstrate that the proportion of insulin-reactive CD4+ T cells present in islets is predicted by the frequency of these negatively charged CDR3{beta} amino acid sequences. Our results suggest diagnostic uses of T cell repertoire profiling in early detection of insulin autoimmunity, and inform ongoing efforts to improve tolerance induction to insulin and prevention of T1D [7].

genomics↗

Peripheral tolerance to insulin is encoded by mimicry in the microbiome

How organisms achieve sustained peripheral tolerance throughout their lifetime, a correct immune discrimination between self and non-self, remains poorly understood. Host-microbiome interactions carry fundamental information that facilitates this process. We hypothesize that commensal microbes are under evolutionary pressure to develop epitopes that, when presented along with other antigens from their own bacterial community, lead to an overall tolerogenic self classification by the host immune system. Hosts, which have co-evolved with commensals, may rely on mimotopes, bacterial epitopes that are indistinguishable from key self epitopes, as a homeostatic feedback mechanism to establish and maintain tolerance. Using a probabilistic sequence model of peptide mimicry, we show that the gut microbiome contains a set of genes that are likely to trigger identical immune responses to insulin B 9-25, a widely distributed self epitope across tissues and the primary autoantigen in type 1 diabetes. Similarities in the antigen receptor sequences determined from CD4 T cells reacting to insulin epitopes and mimotopes provide experimental evidence for mimicry. All predicted high posterior probability mimotopes belong to the transketolase superfamily, an enzyme that allows efficient harvest of commensal-derived sugar polymers and dietary fibre, an advantage during host colonisation. Microbial transketolase upregulation during infant weaning coincides in time with the peak in autoantibody development against insulin. Abundance changes in bacterial genera that carry these mimotopes have also been observed to precede disease diagnosis. Our findings suggest gut dysbiosis followed by immune response to insulin mimotopes as a primary cause of type 1 diabetes, and may contribute towards unraveling similar causal patterns in a wide variety of disorders.

immunology↗

Targeted metagenomic sequencing enhances the identification of pathogens associated with acute infection.

The routine identification of pathogens during infection remains challenging because it relies on multiple modalities such as culture and nucleic acid amplification and tests that tend to be specific for very few of an enormous number of possible infectious agents. Metagenomics promises single-test identification, but shotgun sequencing remains unwieldy and expensive or in many cases insufficiently sensitive to detect the amount of pathogen material in a clinical sample. Here we present the validation and application of Castanet, a method for metagenomic sequencing with enrichment that exploits clinical knowledge to construct a broad panel of relevant organisms for detection at low cost with sensitivity comparable to PCR. Castanet targets both DNA and RNA, works with small sample volumes, and can be implemented in a high-throughput diagnostic setting. We used Castanet to analyse plasma samples from 573 patients from the GAinS sepsis cohort and CSF samples from 243 patients from the ChiMES meningitis cohort that had been evaluated using standard clinical microbiology methods, identifying relevant pathogens in many cases where no pathogen had previously been detected. Castanet is intended for use in defining the distribution of pathogens in samples, diseases and populations, for large-scale clinical studies and for verifying the performance of routine testing regimens. By providing sequence as output, Castanet combines pathogen identification directly with subtyping and phylo-epidemiology.

microbiology↗