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Wieking, G.

Publications and source records attributed to Wieking, G..

7 recordsLinked to original sources

Spatial Transcriptomics Reveals Compartment-Specific Immune Activation Signatures in Ileal and Lymph Node Tissue in Treated HIV Infection

People with HIV (PWH) on long-term antiretroviral therapy (ART) continue to experience elevated rates of morbidities and mortality driven by persistent immune activation despite viral suppression. Known contributors include low-level HIV provirus activity, microbial translocation in part from epithelial barrier dysfunction, microbiome dysfunction, and co-infections. However, how these interact and where they predominate across tissue compartments remains incompletely defined. Here, we applied spatial transcriptomics to characterize compartment-specific transcriptional programs in ileum (epithelium, Peyer's patches, lamina propria) and inguinal lymph nodes (B Cell follicles and T cell zone) from ten PWH on long-term ART, stratified by CD4/CD8 ratio into low-ratio and high-ratio groups, with low-ratio as a proxy for immune activation and increased risk for non-AIDS related serious event. Comparison of global expression found significant differences between groups in four of five compartments. Differential expression analysis identified 483 differentially expressed genes across four of five compartments, with the greatest burden in the T-cell zone and none in the lamina propria. Gene set enrichment analysis identified 116 enriched pathways predominantly in the low-ratio group, spanning immune activation, infection-associated, and metabolic programs, with Peyer's patches showing the broadest transcriptional divergence of any compartment. Cross-compartment signals included higher expression of ORMDL3 and ARL17B in the low-ratio group implicating mitochondrial stress and inflammasome activation, lower expression of CCL3L3 and FCMR in the low-ratio group suggesting impaired immune execution, and divergent ribosomal protein programs between B-cell follicles and the T-cell zone. Cell deconvolution identified compartment-specific differences in estimated immune cell proportions, and T-cell zone gene expression showed significant associations with HIV reservoir measures and plasma markers of microbial translocation and immune activation. Together these findings support spatially heterogeneous immune activation as a feature of persistent immune dysregulation in treated HIV infection and provide compartment-resolved, hypothesis-generating evidence for the tissue-specific mechanisms driving inflammation in this population.

bioinformatics↗

Plasma metabolomics reveals lipid-predominant metabolic disruptions in virologically suppressed people with HIV

People with HIV (PWH) on antiretroviral therapy (ART) experience excess morbidity and mortality from comorbidities including cardiovascular and metabolic disease, yet the biological mechanisms underlying these outcomes in virally suppressed PWH (VS-PWH) remain incompletely understood. We applied high-dimensional targeted plasma metabolomics to quantify 254 small molecules and 750 lipids across 49 classes in viremic PWH (Vi-PWH), VS-PWH, and people without HIV (PWoH), analyzed alongside multiple T cell metrics and plasma cytokine concentrations. Globally, the plasma metabolome of VS-PWH was indistinguishable from PWoH, while Vi-PWH exhibited substantial metabolic disruption characterized by depletion of phosphatidylcholines, sphingomyelins, and hexosylceramides alongside triglyceride accumulation, dysregulation of the tryptophan-kynurenine and arginine-citrulline axes, and elevations in diacetylated polyamines and N4-acetylcytidine. Ordinal trend analysis identified subtle but consistent residual alterations in VS-PWH, particularly within phosphatidylcholine and sphingomyelin classes, that correlated with elevated TNF and reduced CD4+ T cell counts and CD4/CD8 ratio. Together, these findings indicate that residual TNF-associated inflammation and incomplete T cell recovery continue to shape the plasma metabolome in treated HIV, identifying candidate biomarkers for further mechanistic and clinical investigation.

microbiology↗

Multi-omics links microbial dysbiosis, systemic inflammation and metabolomic disruptions to SNAE risk in treated HIV

Serious non-AIDS events (SNAEs), including non-AIDS malignancies, cardiovascular disease, and hepatic complications, remain major causes of mortality in treated HIV infection. These outcomes are driven by persistent immune activation, systemic inflammation, and metabolic dysfunction despite effective viral suppression with antiretroviral therapy (ART). To investigate mechanisms underlying SNAE pathogenesis, we performed a cross-site multi-omic analysis integrating plasma proteins, plasma metabolites, and mucosal microbiomes (ileum and rectum) in 82 ART-treated people with HIV (PWH) and 10 people without HIV (PWoH) from the United States and Mexico. Geography was the dominant source of variation, particularly across lipid classes. However, individuals at high risk for SNAEs, defined by low CD4 T cell counts and low CD4/CD8 ratios, shared a consistent signature of systemic inflammation, mitochondrial dysfunction, and microbial dysbiosis including elevated plasma IL-6, {omega}-oxidation products (adipic and suberic acids), and depletion of short-chain fatty acid-producing commensals in the gut mucosa, including Akkermansia muciniphila, Bacteroides uniformis, and Ruminococcus. Notably, A. muciniphila abundance correlated with lower IL-6 levels, fewer HIV RNA-producing cells in lymph nodes, and higher CD4/CD8 ratios. Together, these findings identify a shared inflammatory and metabolic phenotype in PWH and implicate A. muciniphila as a potential microbiome-based target to mitigate immune activation and SNAE risk in treated HIV.

immunology↗

HIV-producing resting T cells monopolize virus production, associated PANoptosis, and persistence in lymphoid tissue

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=147 SRC="FIGDIR/small/703840v1_ufig1.gif" ALT="Figure 1"> View larger version (43K): org.highwire.dtl.DTLVardef@167c265org.highwire.dtl.DTLVardef@10ba2beorg.highwire.dtl.DTLVardef@e97e06org.highwire.dtl.DTLVardef@150c07c_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphic:C_FLOATNO In chronic HIV infection, HIV is produced before antiretroviral therapy (ART) by resting CD4+ T cells in lymphoid tissue germinal centers. Virus production is associated with destruction of T cells, follicular dendritic cells (FDCs), and B cells required for humoral immune responses by PANoptosis (apotosis, pyroptosis and necroptosis) mediated by the PANoptosome, a cellular structure that incorporates cell contents and programmed cell death pathways in a nodal latticework that mediates cell emptying and disruption in progressive stages indicated by the numbers. During ART, persistent HIV-producing resting T cells represent an immediate source of virus for infection rebound on treatment interruption. C_FIG Activated CD4+ T cells have long been considered the principal source of HIV production before treatment and reactivated latently infected cells the source of virus rebound on treatment interruption, based largely on studies of peripheral blood T cells. Here we show before ART in the lymphoid tissue reservoir that HIV-producing resting CD4+ T cells are essentially the sole source of virus production in germinal centers. Virus is produced in infection complexes of virus bearing follicular dendritic cells (FDCs) that induce high multiplicity multi-HIV-DNA copy infections in overlying resting T cells. HIV production is associated with destruction by PANoptosis (pyroptosis, necroptosis and apoptosis) of interacting antibody-producing populations of FDCs, T cells and B cells. PANoptosis is mediated by the PANoptosome, visualized and defined here as a cellular structure incorporating cytoplasmic and nuclear contents and programmed cell death pathway components in a nodal latticework that executes cell emptying and disruption. During ART, HIV-producing resting T cells persist in lymphoid tissues when virus is undetectable in peripheral blood. These HIV-producing resting T cells that persist during ART represent an immediate source of virus to reignite infection on treatment interruption and are thus identified as an important new target for functional cure strategies.

microbiology↗

HIV lymphoid tissue fibrosis occurs in the earliest stages of acute HIV infection and is associated with macrophage-derived TGF-β

HIV infection is associated with lymphatic tissue damage caused by collagen deposition in the fibroblastic reticular cell network (FRCn) of the parafollicular T cell zone (TZ), which leads to impaired antigen presentation, T cell depletion, and reduced antibody formation. In treated chronic HIV infection, damage persists despite antiretroviral therapy (ART), but it is not known if very early initiation of ART could limit damage and preserve immune function. We studied participants in the Thai RV254 acute infection cohort and found significant collagen deposition in the FRCn even in the earliest Fiebig stage 1 acute infection. The amount of TZ collagen correlates with the frequency of TGF-{beta}+ macrophages which, in turn, correlates with the frequency of HIV RNA-producing cells. We conclude that immediate initiation of ART may have limited impact in preventing or reversing collagen accumulation in LNs.

microbiology↗

Ongoing lymphoid HIV production drives pyroptosis and GLP-1 counter-regulation in ART-suppressed infection

Despite effective antiretroviral therapy (ART), many people with HIV (PWH) exhibit persistent immune activation (IA) and suffer metabolic comorbidities. We investigated whether residual HIV production in lymphoid tissues drives IA. Among 20 ART-suppressed PWH, HIV RNA+ cells were detected in lymph nodes and correlated directly with markers of pyroptosis, assessed via cleaved gasdermin D positivity, but not with most plasma cytokines or IA markers. Notably, glucagon-like peptide 1 (GLP-1), an enteroendocrine hormone with anti-inflammatory roles, was upregulated in the ileum of PWH and correlated directly with systemic cytokines but inversely with lymph node pyroptosis. These findings suggest that chronic occult inflammation in people with successfully suppressed HIV infection is mediated by persistent virus production in lymph nodes leading to pyroptosis, which may trigger compensatory anti-inflammatory enteroendocrine activation that may dampen pyroptosis. Targeting pyroptosis or enhancing GLP-1 signaling represent potential therapeutic strategies for modulating IA and managing metabolic comorbidities in PWH. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=140 SRC="FIGDIR/small/698696v1_ufig1.gif" ALT="Figure 1"> View larger version (37K): org.highwire.dtl.DTLVardef@af8909org.highwire.dtl.DTLVardef@4dbc95org.highwire.dtl.DTLVardef@197ff48org.highwire.dtl.DTLVardef@1f9051a_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

The Defenders of the Alveolus Succumb in COVID-19 Pneumonia to SARS-CoV-2, Necroptosis, Pyroptosis and Panoptosis

The alveolar type II (ATII) pneumocyte has been called the defender of the alveolus because, amongst the cells many important roles, repair of lung injury is particularly critical. We investigated the extent to which SARS-CoV-2 infection incapacitates the ATII reparative response in fatal COVID-19 pneumonia, and describe massive infection and destruction of ATI and ATII cells. We show that both type I interferon-negative infected ATII and type I-interferon-positive uninfected ATII cells succumb to TNF-induced necroptosis, BTK-induced pyroptosis and a new PANoptotic hybrid form of inflammatory cell death that combines apoptosis, necroptosis and pyroptosis in the same cell. We locate pathway components of these cell death pathways in a PANoptosomal latticework that mediates emptying and disruption of ATII cells and destruction of cells in blood vessels associated with microthrombi. Early antiviral treatment combined with inhibitors of TNF and BTK could preserve ATII cell populations to restore lung function and reduce hyperinflammation from necroptosis, pyroptosis and panoptosis. Graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=125 SRC="FIGDIR/small/503050v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@8bf28dorg.highwire.dtl.DTLVardef@1e1335eorg.highwire.dtl.DTLVardef@1f3a0e2org.highwire.dtl.DTLVardef@1c77c62_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIIn fatal COVID-19 pneumonia, the initial destruction of Type II alveolar cells by SARS-CoV-2 infection is amplified by infection of the large numbers of spatially contiguous Type II cells supplied by the proliferative reparative response. C_LIO_LIInterferon-negative infected cells and interferon-positive uninfected cells succumb to inflammatory forms of cell death, TNF-induced necroptosis, BTK-induced pyroptosis, and PANoptosis. C_LIO_LIAll of the cell death pathway components, including a recently identified NINJ1 component, are localized in a PANoptosome latticework that empties in distinctive patterns to generate morphologically distinguishable cell remnants. C_LIO_LIEarly combination treatment with inhibitors of SARS-CoV-2 replication, TNF and BTK could reduce the losses of Type II cells and preserve a reparative response to regenerate functional alveoli. C_LI

immunology↗