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Kupz, A.

Publications and source records attributed to Kupz, A..

9 recordsLinked to original sources

Malnourishment and expanded microbiome maintain superior efficacy of the recombinant tuberculosis vaccine BCG::ESAT-6-PE25SS

Tuberculosis (TB) remains the leading cause of infectious mortality. The limited efficacy of the only TB vaccine, Bacille Calmette-Guerin (BCG) against pulmonary disease necessitates improved vaccines. Host factors such as malnutrition and microbiome composition shape immune responses in humans, though these factors are overlooked in preclinical vaccine evaluation. Here we show that a recombinant BCG strain, BCG::ESAT-6-PE25SS, confers superior protection compared to BCG across murine models of malnutrition, antibiotic-induced dysbiosis and environmentally enriched microbiota. Unexpectedly, malnourished mice displayed reduced Mycobacterium tuberculosis (Mtb) burden, associated with altered host metabolism and immune composition. Microbiome disruption increased TB susceptibility, whereas diversification of microbiota enhanced resistance and immune heterogeneity. Vaccine efficacy correlated with enrichment of known immunomodulatory microbial taxa. These findings suggest diet-microbiome-immunity interactions as potential key determinants of TB pathogenesis and provide evidence for the importance of vaccine candidate evaluation under physiologically relevant co-morbid conditions

microbiology↗

mRNA-based prime-and-pull vaccination combines benefits of subcutaneous and mucosal BCG vaccination

Pulmonary vaccination has been proposed as a strategy to improve protection against tuberculosis, due to the generation of immune cells that more efficiently survey and eliminate infected cells within the lung. However, uncontrolled replication and excessive inflammation associated with mucosal delivery of live-attenuated vaccines highlight the need for alternative strategies that balance efficacy and safety. Here, we describe a prime-and-pull vaccination approach in which systemic immunity is established by subcutaneous BCG vaccination, followed by the induction of local lung immunity through mucosal delivery of lipid nanoparticle-formulated multi-antigen mRNA. Proof-of-concept studies using a model antigen demonstrated the induction of polyfunctional antigen-specific T cells in the lung with minimal inflammatory cell infiltration, compared with mucosal BCG vaccination. Eight Mycobacterium tuberculosis- and BCG-derived proteins were subsequently selected to generate four multi-antigen mRNA constructs. In vivo vaccination and challenge experiments demonstrated that this prime-and-pull strategy is well tolerated and confers protective immunity against tuberculosis in a murine model. Collectively, these data support a modular mRNA-based prime-and-pull vaccination strategy as a translational approach that bridges the improved immunogenicity and efficacy of mucosal BCG vaccination with the safety profile of parenteral BCG administration. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=110 SRC="FIGDIR/small/739464v1_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@c0635borg.highwire.dtl.DTLVardef@bb0357org.highwire.dtl.DTLVardef@1d87243org.highwire.dtl.DTLVardef@135bcd7_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Pulmonary delivery of antigen-enhanced BCG overcomes safety barriers in immunocompromised hosts and protects against TB in the absence of adaptive immunity.

The low efficacy of Bacille Calmette-Guerin (BCG) in preventing pulmonary tuberculosis (TB) underscores the need for improved TB vaccines. Recombinant BCG (rBCG) strains secreting the virulence-associated effector molecule ESAT-6 from Mycobacterium tuberculosis (Mtb) markedly improve efficacy and immunogenicity in animal models of TB but have been considered unsuitable for clinical translation due to safety concerns identified in intravenous SCID mouse models. Here, we demonstrate that pulmonary delivery fundamentally reshapes the safety and protective efficacy of the ESAT-6-secreting rBCG strains, BCG::RD1 and BCG::ESAT6-PE25SS. In sharp contrast to intravenous delivery, pulmonary administration was markedly better tolerated, improved survival, and reduced systemic dissemination and brain pathology of severely immunocompromised mice. Strikingly, pulmonary rBCG vaccination also conferred superior protection against aerosol Mtb challenge in wild-type, type 2 diabetic, and adaptive immunity-deficient Rag1-/- and Rag2-/-Il2rg-/- mice, with BCG::RD1 showing the strongest adaptive immunity-independent protection. Mechanistically, pulmonary rBCG vaccination promoted lung innate immune activation, expansion of myeloid-biased progenitors in the bone marrow, and enhanced antimycobacterial activity of macrophages, consistent with trained innate immunity. Collectively, these findings reveal that pulmonary vaccination largely overcomes safety concerns of ESAT-6-secreting rBCG strains and provide preclinical evidence for a viable strategy to improve protection against TB in immunocompromised individuals.

immunology↗

CD8+ T cells mediate vaccination-induced lymphatic containment of latent Mycobacterium tuberculosis infection following immunosuppression, while B cells are dispensable

It is estimated that two billion people are latently infected with Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB). Latent Mtb infection (LTBI) can occur in multiple organs, including the lymphatics. The risk of LTBI reactivation increases in immunocompromised conditions, such as coinfection with human immunodeficiency virus (HIV), and during treatment of autoimmune diseases and organ transplantation. The immunological correlates of protection against TB, including against reactivation of LTBI, remain largely elusive. Here, we used a mouse model of latent lymphatic Mtb infection to dissect the immunological mechanisms underlying LTBI containment versus reactivation. We show that immunosuppression-mediated reactivation of lymphatic LTBI and the subsequent spread to non-lymphatic organs can be prevented by vaccination with multiple recombinant BCG (rBCG) strains despite the deficiency of CD4+ T cells. Using spatial transcriptomics, multi-parameter imaging, network analysis and bioinformatic integration of histopathological images, we reveal that immunosuppression is associated with a distinct repositioning of non-CD4 immune cells at the edge of TB lesions within the infection-draining cervical lymph nodes. While B cells increased in numbers, they are dispensable for the containment of LTBI. Lymphatic Mtb infection in different immune cell-deficient mouse strains, antibody-mediated cell depletion and adoptive transfer experiments into highly susceptible mice unequivocally show that vaccination-mediated prevention of LTBI reactivation is critically dependent on CD8+ T cells. These findings have profound implications for our understanding of immunity to TB and the management of LTBI. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=92 SRC="FIGDIR/small/634479v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@151fdd6org.highwire.dtl.DTLVardef@1efed47org.highwire.dtl.DTLVardef@c2e7e0org.highwire.dtl.DTLVardef@555c7_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Lung epithelial progenitor-mediated release of TGF-β regulates induction and persistence of lung CD8+ TRM cells following mucosal BCG vaccination

A principal reason for the high global morbidity and mortality of tuberculosis (TB) is the lack of efficacy of the only licensed TB vaccine, Bacillus Calmette-Guerin (BCG), as parenteral BCG does not induce local pulmonary immune memory. Animal studies have shown that mucosal BCG vaccination provides superior protection against TB due to generation of lung resident memory T cells (TRM). Here, we demonstrated that following mucosal vaccination with the genetically modified virulent BCG strain, BCG::RD1, distal airway epithelial progenitors were mobilized to assist with restoration of alveolar epithelium. By way of their migration-mediated activation of latent TGF-{beta}, lung CD8+ TRM differentiation was induced. Mucosal vaccinations using nonvirulent strains of BCG in which airway epithelial progenitors were not mobilized, as well as genetic inhibition of migration-mediated activation of TGF-{beta}, resulted in significantly lower numbers of lung CD8+ TRM. In addition, we discovered CD8+ cells with ex-lung and stem-like TRM phenotypes that persisted in the lung-draining mediastinal lymph nodes for up to four months following mucosal BCG vaccination. These results link airway epithelial progenitor-mediated repair of injured lung tissue with induction of resident T cell memory and delineate why persistence of TRM in the lung is short-lived. These findings may explain why mucosal vaccination with virulent BCG strains is more protective against TB and thus have notable implications for future TB vaccine development. One Sentence SummaryFollowing lung damage due to inhalation of virulent BCG, distal airway epithelial progenitor cells interact with lung CD8+ T cells to induce their differentiation into resident memory T cells via migration-mediated activation of TGF-{beta}.

immunology↗

A modular self-assembling and self-adjuvanting multiepitope peptide nanoparticle vaccine platform to improve the efficacy and immunogenicity of BCG

After more than a century since its initial development, Bacille Calmette-Guerin (BCG) remains the only licensed vaccine against tuberculosis (TB). Subunit boosters are considered a viable strategy to enhance BCG efficacy, which often wanes in adolescence. While many studies on booster subunit vaccines have concentrated on recombinant proteins, here we developed a novel modular peptide-based subunit vaccine platform that is flexible, cold-chain independent and customizable to diverse circumstances and populations. Each individual peptide building block consists of a linear arrangement comprising a 15-leucine self-assembly inducer moiety, a Mycobacterium tuberculosis (Mtb) target epitope and an HLA-E binding moiety, with each moiety separated by a triple lysine spacer. The building blocks, in any combination, were able to form a multiepitope nanoparticle. Six Mtb epitopes were selected to produce the self-assembling and self-adjuvanting peptide-based TB nano-vaccine candidate PNx6. In vivo vaccination-challenge experiments demonstrated that subcutaneous boost of parenteral BCG immunization with PNx6 significantly enhanced its immunogenicity and improved its protective efficacy in a murine model of TB by more than 5-fold. Our study present evidence that purely amphiphilic peptides self-assemble into self-adjuvanting nanoparticles with appropriate size and morphology for TB vaccination with great potential for a multitude of other diseases.

microbiology↗

Disparate effects of metformin on Mycobacterium tuberculosis infection in diabetic and non-diabetic mice

Comorbid type 2 diabetes poses a great challenge to the global control of tuberculosis. Here we assessed the efficacy of metformin (MET); an anti-diabetic drug, in mice infected with a very-low dose of Mycobacterium tuberculosis. In contrast to diabetic mice, infected non-diabetic mice that received the same therapeutic concentration of MET presented with significantly higher disease burden. This warrants further studies to investigate the disparate efficacy of MET against tuberculosis in diabetic and non-diabetic individuals.

microbiology↗

Inflammasome-independent role for NLRP3 in controlling innate anti-helminth immunity and tissue repair in the lung

Alternatively activated macrophages are essential effector cells during type 2 immunity and tissue repair following helminth infections. We previously showed that Ym1, an alternative activation marker, can drive innate IL-1R-dependent neutrophil recruitment during infection with the lung-migrating nematode, Nippostrongylus brasiliensis suggesting a potential role for the inflammasome in the IL-1-mediated innate response to infection. While inflammasome proteins such as NLRP3 have important pro-inflammatory functions in macrophages, their role during type 2 responses and repair are less defined. We therefore infected Nlrp3-/- mice with N. brasiliensis. Unexpectedly, compared to WT mice, infected Nlrp3-/- mice had increased neutrophilia and eosinophilia, correlating with enhanced worm killing but at the expense of increased tissue damage and delayed lung repair. Transcriptional profiling showed that infected Nlrp3-/- mice exhibited elevated type 2 gene expression compared to WT mice. Notably, inflammasome activation was not evident early post-infection with N. brasiliensis and in contrast to Nlrp3-/- mice, anti-helminth responses were unaffected in caspase-1/11 deficient or WT mice treated with the NLRP3-specific inhibitor MCC950. Together these data suggest that NLRP3 can constrain lung neutrophilia and helminth killing and negatively regulate type 2 immune responses in an inflammasome-independent manner.

immunology↗

Treatment of mice with IL2-complex enhances inflammasome-driven IFN-γ production and prevents lethal toxoplasmosis

Toxoplasmic encephalitis is an AIDS-defining condition in HIV+ individuals. The decline of IFN-{gamma}-producing CD4+ T cells in AIDS is a major contributing factor in reactivation of quiescent Toxoplasma gondii to an actively replicating stage of infection. Hence, it is important to identify CD4-independent mechanisms to control acute T. gondii infection. Here we have investigated the targeted expansion and regulation of IFN-{gamma} production by CD8+ T cells, DN T cells and NK cells in response to T. gondii infection using IL-2 complex (IL2C) pre-treatment in an acute in vivo mouse model. Our results show that expansion of CD8+ T cells, DN T cells and NK cell by S4B6 IL2C treatment increases survival rates of mice infected with T. gondii and this increased survival is dependent on both IL-12- and IL-18-driven IFN-{gamma} production. Processing and secretion of IFN-{gamma}-inducing, bioactive IL-18 is dependent on the sensing of active parasite invasion by multiple redundant inflammasome sensors in multiple hematopoietic cell types but independent from T. gondii-derived dense granule (GRA) proteins. Our results provide evidence for a protective role of IL2C-mediated expansion of CD8+ T cells, DN T cells and NK cells in murine toxoplasmosis and may represent a promising adjunct therapy for acute toxoplasmosis.\n\nAuthor SummaryA third of the worlds population is chronically infected with the parasite Toxoplasma gondii. In most cases the infection is asymptomatic, but in individuals suffering from AIDS, reactivation of brain and muscle cysts containing T. gondii is a significant cause of death. The gradual decline of CD4 T cells, the hallmark of AIDS, is believed to be a major contributing factor in reactivation of T. gondii infection and the development of acute disease. In this study, we show that targeted expansion of non-CD4 immune cell subsets can prevent severe disease and premature death via increased availability of interferon gamma-producing immune cells. We also demonstrate that the upstream signaling molecule interleukin-18 is required for the protective immune response by non-CD4 cells and show that the sensing of active parasite invasion by danger recognition molecules is crucial. Our findings reveal that targeted cell expansion may be a promising therapy in toxoplasmosis and suggests that the development of novel intervention strategies targeting danger recognition pathways may be useful against toxoplasmosis, particularly in the context of AIDS.

microbiology↗