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Biology subjects

Rhein, J.

Publications and source records attributed to Rhein, J..

3 recordsLinked to original sources

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↗

Pre-treatment Microbiome Diversity and Function is associated with Expansion of Cytotoxic and Regulatory Immune Populations after N-803 treatment in People with HIV

BackgroundN-803, an IL-15 superagonist, is currently being studied in clinical trials as a treatment to reverse HIV latency. However, its effects on the gut microbiome are not well understood. MethodsIn this longitudinal metagenomic study, we analyzed fecal microbiomes from ART-suppressed people with HIV at four different timepoints before, during, and after N-803 treatment. ResultsOverall taxonomic and functional diversity did not change significantly, yet beneficial microbial taxa and pathways were enriched after N-803. Specifically, the relative abundance of Faecalibacterium prausnitzii increased significantly after N-803, whereas histidine degradation pathways, often associated with pro-inflammatory mucosal state, decreased. A higher baseline microbial diversity correlated with stronger CD8+ and natural killer (NK) cells activation and reduced frequency of rectal HIV RNA+ cells. MaAsLin2 analyses further associated short-chain fatty acid (SCFA)-producing taxa and pathways with increased immune activation markers. ConclusionsThese results indicate that gut microbiome diversity prior to immunotherapy influences host response and suggest that microbiome-based strategies could improve efforts to cure HIV.

microbiology↗

Convergent epitope specificities, V gene usage and public clones elicited by primary exposure to SARS-CoV-2 variants

An important consequence of infection with a SARS-CoV-2 variant is protective humoral immunity against other variants. The basis for such cross-protection at the molecular level is incompletely understood. Here we characterized the repertoire and epitope specificity of antibodies elicited by Beta, Gamma and ancestral variant infection and assessed their cross-reactivity to these and the more recent Delta and Omicron variants. We developed a high-throughput approach to obtain immunoglobulin sequences and produce monoclonal antibodies for functional assessment from single B cells. Infection with any variant elicited similar cross-binding antibody responses exhibiting a remarkably conserved hierarchy of epitope immunodominance. Furthermore, convergent V gene usage and similar public B cell clones were elicited regardless of infecting variant. These convergent responses despite antigenic variation may represent a general immunological principle that accounts for the continued efficacy of vaccines based on a single ancestral variant.

immunology↗