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Wuethrich, M.

Publications and source records attributed to Wuethrich, M..

6 recordsLinked to original sources

Combination adjuvants drive long lived plastic Th17 cells that convert to multi-functional Th1 cells and protect mice against fungal infection

Th1 cells are viewed as a cornerstone of immunity to fungi and other intracellular pathogens. Despite the widely accepted role of Th1 cells in antifungal resistance, the development of protective strategies harnessing them is stunted by a limited understanding of how best to promote their development. We and others have reported a requisite role for Th17 cells in resistance to fungi. We have long been puzzled about how to reconcile seminal roles for both Th1 and Th17 subsets. Here we report that Th17 cells convert into polyfunctional Th1 cells producing multiple cytokines, including IFN-{gamma}, TNF and GM-CSF when we used adjuvant formulations that include glucopyranosyl lipid adjuvant (GLA) to enhance antifungal immunity. GLA induced plastic Th17 cells that convert into polyfunctional Th1 memory cells.

immunology↗

Endoglucanase-2 (Eng2), a conserved immunodominant antigen in dimorphic fungi that elicits immunity and resistance during infection

Herein, we describe a conserved surface and cell wall protein, Endoglucanase 2 (Eng2), expressed on the etiological agents that cause the endemic systemic mycoses of North America - Blastomyces, Coccidioides and Histoplasma. We demonstrate that despite sequence variation of the protein across these related fungi, exposure to Eng2 vaccinates and protects inbred and humanized HLA-DR4 strains of mice against lethal experimental infections with these fungi by eliciting adaptive immunity mediated by CD4 T cells. We also show that CD4 T cell precursors against Eng2 are detectable in naive individuals and that patients who have recovered from these infections evince a memory and recall CD4 T cell response to Eng2 and its immunodominant epitopes that we have mapped. We create and catalogue new tools and information such as immunodominant peptide epitopes of Eng2 from each fungus recognized by inbred mice and human subjects and we engineer novel peptide-MHC II tetramers for tracking T cells in inbred and HLA-DR4 humanized mice that will be useful for those who study these infections in mice and humans. Lastly, because most patients demonstrate memory and recall responses against Eng2, our work oRers new tools for diagnosis of this collection of infectious diseases across North America.

immunology↗

Identification of a unique TUBB3+ cell population in the tuberculosis granuloma

Tuberculosis (TB), caused by Mycobacterium tuberculosis, remains a leading cause of mortality worldwide. Granulomas, hallmark structures of TB in the lungs and other infected tissues, are critical sites of host-pathogen interactions, yet their full cellular composition is not completely understood. Here, we identify a previously unrecognized {beta}3-tubulin (TUBB3)-positive cell population within TB granulomas in mice, guinea pigs, non-human primates, and TB patients. TUBB3 is a well-established pan-neuronal marker, yet these TUBB3+ cells are distinct from typical pulmonary resident cells and leukocytes. They exhibit a branched, elongated morphology, which is suggestive of neuron-like features. Intriguingly, their appearance is independent of adaptive immunity and is also observed in viral and fungal infections, but not in asthma. Our findings suggest the existence of a neuro-immune component within granulomas that may influence TB pathogenesis. Further investigation into the origin, function, and signaling pathways of these TUBB3+ cells is required to clarify their identity and potential role in host defense, which could reveal novel therapeutic targets for TB and other pulmonary infections.

immunology↗

Novel populations of CD4+ T cells associated with vaccine efficacy

Memory T cells underpin vaccine-induced immunity but are not yet fully understood. To distinguish features of memory cells that confer protective immunity, we used single cell transcriptome analysis to compare antigen-specific CD4+ T cells recalled to lungs of mice that received a protective or nonprotective subunit vaccine followed by challenge with a fungal pathogen. We unexpectedly found populations specific to protection that expressed a strong type I interferon response signature, whose distinctive transcriptional signature appeared unconventionally dependent on IFN-{gamma} receptor. We also detected a unique population enriched in protection that highly expressed the gene for the natural killer cell marker NKG7. Lastly, we detected differences in TCR gene use and in Th1- and Th17-skewed responses after protective and nonprotective vaccine, respectively, reflecting heterogeneous Ifng- and Il17a-expressing populations. Our findings highlight key features of transcriptionally diverse and distinctive antigen-specific T cells associated with protective vaccine-induced immunity.

immunology↗

Combination adjuvants enhance recombinant protein vaccine protection against fungal infection

The development of effective vaccines against fungal infections requires the induction of protective, pathogen-specific cell mediated immune responses. Here, we asked whether combination adjuvants based on delta inulin (Advax) formulated with TLR agonists could improve vaccine protection mediated by a fungal recombinant protein, Bl-Eng2, which itself harbors an immunodominant antigen and Dectin-2 agonist/adjuvant. We found that Bl-Eng2 formulated with Advax3 containing TLR9 agonist or Advax8, containing TLR4 agonist, provided the best protection against pulmonary infection with Blastomyces dermatitidis, being more effective than Freunds complete adjuvant or Adjuplex. Advax3 was most efficient in inducing IFN-{gamma} and IL-17 producing antigen-specific T cells that migrated to the lung upon Blastomyces dermatitidis infection. Mechanistic studies revealed Bl-Eng2/Advax3 protection was tempered by neutralization of IL-17 and particularly IFN-{gamma}. Likewise, greater numbers of lung-resident T cells producing IFN-{gamma}, IL-17, or IFN-{gamma}+ and IL-17+ correlated with fewer fungi recovered from lung. Protection was maintained after depletion of CD4+ T cells, partially reduced by depletion of CD8+ T cells, and completely eliminated after depletion of both CD4+ and CD8+ T cells. We conclude that Bl-Eng2 formulated with Advax3 is promising for eliciting vaccine-induced antifungal immunity, through a previously uncharacterized mechanism involving CD8+ and also CD4+ T cells producing IFN-{gamma} and/or IL-17. Although no licensed vaccine exists as yet against any fungal disease, these findings indicate the importance of adjuvant selection for the development of effective fungal vaccines. IMPORTANCEFungal disease remains a challenging clinical and public health problem. Despite medical advances, invasive fungal infections have skyrocketed over the last decade and pose a mounting health threat in immune-competent and -deficient hosts with worldwide mortality rates ranking 7th, even ahead of tuberculosis. The development of safe, effective vaccines remains a major hurdle for fungi. Critical barriers to progress include the lack of defined fungal antigens and suitable adjuvants. Our research is significant in identifying adjuvant combinations that elicit optimal vaccine-induced protection when formulated with a recombinant protective antigen and uncovering the mechanistic bases of the underlaying vaccine protection, which will foster the strategic development of anti-fungal vaccines.

immunology↗

Structural basis of Blastomyces Endoglucanase-2adjuvancy in anti-fungal and -viral immunity

The development of safe subunit vaccines requires adjuvants that augment immunogenicity of non-replicating protein-based antigens. Current vaccines against infectious diseases preferentially induce protective antibodies driven by adjuvants such as alum. However, the contribution of antibody to host defense is limited for certain classes of infectious diseases such as fungi, whereas animal studies and clinical observations implicate cellular immunity as an essential component of the resolution of fungal pathogens. Here, we decipher the structural bases of a newly identified glycoprotein ligand of Dectin-2 with potent adjuvancy, Blastomyces endoglucanase-2 (Bl-Eng2). We also pinpoint the developmental steps of antigen-specific CD4+ and CD8+ T responses augmented by Bl-Eng2 including expansion, differentiation and tissue residency. Dectin-2 ligation led to successful systemic and mucosal vaccination against invasive fungal infection and Influenza A infection, respectively. O-linked glycans on Bl-Eng2 applied at the skin and respiratory mucosa greatly augment vaccine subunit induced protective immunity against lethal influenza and fungal pulmonary challenge. AUTHOR SUMMARYFungal disease remains a challenging clinical and public health problem in part because there is no commercial vaccine available. The lack of suitable adjuvants is a critical barrier to developing safe and effective vaccines against fungal pathogens. Current adjuvants such as alum preferentially induce antibody responses which may be limited in mediating protection against fungi. Clinical observations and animal studies implicate cellular immunity as the essential component for the resolution of fungal infections. We have recently discovered an adjuvant that augments cell mediated immune responses and vaccine induced protection against fungi. Here, we identified the structural and mechanistic requirements by which this newly discovered adjuvant induces cell mediated immunity against fungi. As a proof of principle we also demonstrate that the adjuvant drives cellular immune responses against viruses such as influenza. We anticipate that our adjuvant can be used for vaccination with safe subunit vaccines against many microbial pathogens including viruses, intracellular bacteria, fungi and parasites that require cell mediated immune responses.

immunology↗