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Item Adaptive NK cells in people exposed to Plasmodium falciparum correlate with protection from malaria(Rockefeller University Press, 2019-04-12) Hart, Geoffrey T.; Tran, Tuan M.; Theorell, Jakob; Schlums, Heinrich; Arora, Gunjan; Rajagopalan, Sumati; Sangala, A. D. Jules; Welsh, Kerry J.; Traore, Boubacar; Pierce, Susan K.; Crompton, Peter D.; Bryceson, Yenan T.; Long, Eric O.; Medicine, School of MedicineHow antibodies naturally acquired during Plasmodium falciparum infection provide clinical immunity to blood-stage malaria is unclear. We studied the function of natural killer (NK) cells in people living in a malaria-endemic region of Mali. Multi-parameter flow cytometry revealed a high proportion of adaptive NK cells, which are defined by the loss of transcription factor PLZF and Fc receptor γ-chain. Adaptive NK cells dominated antibody-dependent cellular cytotoxicity responses, and their frequency within total NK cells correlated with lower parasitemia and resistance to malaria. P. falciparum–infected RBCs induced NK cell degranulation after addition of plasma from malaria-resistant individuals. Malaria-susceptible subjects with the largest increase in PLZF-negative NK cells during the transmission season had improved odds of resistance during the subsequent season. Thus, antibody-dependent lysis of P. falciparum–infected RBCs by NK cells may be a mechanism of acquired immunity to malaria. Consideration of antibody-dependent NK cell responses to P. falciparum antigens is therefore warranted in the design of malaria vaccines.Item Altered microbial biogeography in an innate model of colitis(Taylor & Francis, 2022) Boger-May, Antonia; Reed, Theodore; LaTorre, Diana; Ruley-Haase, Katelyn; Hoffman, Hunter; English, Lauren; Roncagli, Connor; Overstreet, Anne-Marie; Boone, David; Microbiology and Immunology, School of MedicineChanges in the spatial organization, or biogeography, of colonic microbes have been observed in human inflammatory bowel disease (IBD) and mouse models of IBD. We have developed a mouse model of IBD that occurs spontaneously and consistently in the absence of adaptive immunity. Mice expressing tumor necrosis factor-induced protein 3 (TNFAIP3) in intestinal epithelial cells (villin-TNFAIP3) develop colitis when interbred with Recombination Activating 1-deficient mice (RAG1−/−). The colitis in villin-TNFAIP3 × RAG1−/− (TRAG) mice is prevented by antibiotics, indicating a role for microbes in this innate colitis. We therefore explored the biogeography of microbes and responses to antibiotics in TRAG colitis. Laser capture microdissection and 16S rRNA sequencing revealed altered microbial populations across the transverse axis of the colon as the inner mucus layer of TRAG, but not RAG1−/−, mice was infiltrated by microbes, which included increased abundance of the classes Gammaproteobacteria and Actinobacteria. Along the longitudinal axis differences in the efficacy of antibiotics to prevent colitis were evident. Neomycin was most effective for prevention of inflammation in the cecum, while ampicillin was most effective in the proximal and distal colon. RAG1−/−, but not TRAG, mice exhibited a structured pattern of bacterial abundance with decreased Firmicutes and Proteobacteria but increased Bacteroidetes along the proximal to distal axis of the gut. TRAG mice exhibited increased relative abundance of potential pathobionts including Bifidobacterium animalis along the longitudinal axis of the gut whereas others, like Helicobacter hepaticus were increased only in the cecum. Potential beneficial organisms including Roseburia were decreased in the proximal regions of the TRAG colon, while Bifidobacterium pseudolongulum was decreased in the TRAG distal colon. Thus, the innate immune system maintains a structured, spatially organized, gut microbiome along the transverse and longitudinal axis of the gut, and disruption of this biogeography is a feature of innate immune colitis.Item Brain astrocytes and microglia express functional MR1 molecules that present microbial antigens to mucosal-associated invariant T (MAIT) cells(Elsevier, 2020-12-15) Priya, Raj; Brutkiewicz, Randy R.; Microbiology and Immunology, School of MedicineIt is unknown whether brain astrocytes and microglia have the capacity to present microbial antigens via the innate immune MR1/MAIT cell axis. We have detected MAIT cells in the normal mouse brain and found that both astrocytes and microglia are MR1+. When we stimulated brain astrocytes and microglia with E. coli, and then co-cultured them with MAIT cells, MR1 surface expression was upregulated and MAIT cells were activated in an antigen-dependent manner. Considering the association of MAIT cells with inflammatory conditions, including those in the CNS, the MR1/MAIT cell axis could be a novel therapeutic target in neuroinflammatory disorders.Item Control of the temporal development of Alzheimer's disease pathology by the MR1/MAIT cell axis(BMC, 2023-03-21) Wyatt‑Johnson, Season K.; Kersey, Holly N.; Codocedo, Juan F.; Newell, Kathy L.; Landreth, Gary E.; Lamb, Bruce T.; Oblak, Adrian L.; Brutkiewicz, Randy R.; Microbiology and Immunology, School of MedicineBackground: Neuroinflammation is an important feature of Alzheimer's disease (AD). Understanding which aspects of the immune system are important in AD may lead to new therapeutic approaches. We study the major histocompatibility complex class I-related immune molecule, MR1, which is recognized by an innate-like T cell population called mucosal-associated invariant T (MAIT) cells. Methods: Having found that MR1 gene expression is elevated in the brain tissue of AD patients by mining the Agora database, we sought to examine the role of the MR1/MAIT cell axis in AD pathology. Brain tissue from AD patients and the 5XFAD mouse model of AD were used to analyze MR1 expression through qPCR, immunofluorescence, and flow cytometry. Furthermore, mice deficient in MR1 and MAIT cells were crossed with the 5XFAD mice to produce a model to study how the loss of this innate immune axis alters AD progression. Moreover, 5XFAD mice were also used to study brain-resident MAIT cells over time. Results: In tissue samples from AD patients and 5XFAD mice, MR1 expression was substantially elevated in the microglia surrounding plaques vs. those that are further away (human AD: P < 0.05; 5XFAD: P < 0.001). In 5XFAD mice lacking the MR1/MAIT cell axis, the development of amyloid-beta plaque pathology occurred at a significantly slower rate than in those mice with MR1 and MAIT cells. Furthermore, in brain tissue from 5XFAD mice, there was a temporal increase in MAIT cell numbers (P < 0.01) and their activation state, the latter determined by detecting an upregulation of both CD69 (P < 0.05) and the interleukin-2 receptor alpha chain (P < 0.05) via flow cytometry. Conclusions: Together, these data reveal a previously unknown role for the MR1/MAIT cell innate immune axis in AD pathology and its potential utility as a novel therapeutic target.Item Coxiella burnetii Blocks Intracellular Interleukin-17 Signaling in Macrophages(American Society for Microbiology, 2018-09-21) Clemente, Tatiana M.; Mulye, Minal; Justis, Anna V.; Nallandhighal, Srinivas; Tran, Tuan M.; Gilk, Stacey D.; Microbiology and Immunology, School of MedicineCoxiella burnetii is an obligate intracellular bacterium and the etiological agent of Q fever. Successful host cell infection requires the Coxiella type IVB secretion system (T4BSS), which translocates bacterial effector proteins across the vacuole membrane into the host cytoplasm, where they manipulate a variety of cell processes. To identify host cell targets of Coxiella T4BSS effector proteins, we determined the transcriptome of murine alveolar macrophages infected with a Coxiella T4BSS effector mutant. We identified a set of inflammatory genes that are significantly upregulated in T4BSS mutant-infected cells compared to mock-infected cells or cells infected with wild-type (WT) bacteria, suggesting that Coxiella T4BSS effector proteins downregulate the expression of these genes. In addition, the interleukin-17 (IL-17) signaling pathway was identified as one of the top pathways affected by the bacteria. While previous studies demonstrated that IL-17 plays a protective role against several pathogens, the role of IL-17 during Coxiella infection is unknown. We found that IL-17 kills intracellular Coxiella in a dose-dependent manner, with the T4BSS mutant exhibiting significantly more sensitivity to IL-17 than WT bacteria. In addition, quantitative PCR confirmed the increased expression of IL-17 downstream signaling genes in T4BSS mutant-infected cells compared to WT- or mock-infected cells, including the proinflammatory cytokine genes Il1a, Il1b, and Tnfa, the chemokine genes Cxcl2 and Ccl5, and the antimicrobial protein gene Lcn2 We further confirmed that the Coxiella T4BSS downregulates macrophage CXCL2/macrophage inflammatory protein 2 and CCL5/RANTES protein levels following IL-17 stimulation. Together, these data suggest that Coxiella downregulates IL-17 signaling in a T4BSS-dependent manner in order to escape the macrophage immune response.Item Derivation, validation, and transcriptomic assessment of pediatric septic shock phenotypes identified through latent profile analyses: Results from a prospective multi-center observational cohort(Research Square, 2023-12-06) Atreya, Mihir R.; Huang, Min; Moore, Andrew R.; Zheng, Hong; Hasin-Brumshtein, Yehudit; Fitzgerald, Julie C.; Weiss, Scott L.; Cvijanovich, Natalie Z.; Bigham, Michael T.; Jain, Parag N.; Schwarz, Adam J.; Lutfi, Riad; Nowak, Jeffrey; Thomas, Neal J.; Quasney, Michael; Dahmer, Mary K.; Baines, Torrey; Haileselassie, Bereketeab; Lautz, Andrew J.; Stanski, Natalja L.; Standage, Stephen W.; Kaplan, Jennifer M.; Zingarelli, Basilia; Sweeney, Timothy E.; Khatri, Purvesh; Sanchez-Pinto, L. Nelson; Kamaleswaran, Rishikesan; Pediatrics, School of MedicineBackground: Sepsis poses a grave threat, especially among children, but treatments are limited due to clinical and biological heterogeneity among patients. Thus, there is an urgent need for precise subclassification of patients to guide therapeutic interventions. Methods: We used clinical, laboratory, and biomarker data from a prospective multi-center pediatric septic shock cohort to derive phenotypes using latent profile analyses. Thereafter, we trained a support vector machine model to assign phenotypes in a hold-out validation set. We tested interactions between phenotypes and common sepsis therapies on clinical outcomes and conducted transcriptomic analyses to better understand the phenotype-specific biology. Finally, we compared whether newly identified phenotypes overlapped with established gene-expression endotypes and tested the utility of an integrated subclassification scheme. Findings: Among 1,071 patients included, we identified two phenotypes which we named 'inflamed' (19.5%) and an 'uninflamed' phenotype (80.5%). The 'inflamed' phenotype had an over 4-fold risk of 28-day mortality relative to those 'uninflamed'. Transcriptomic analysis revealed overexpression of genes implicated in the innate immune response and suggested an overabundance of developing neutrophils, pro-T/NK cells, and NK cells among those 'inflamed'. There was no significant overlap between endotypes and phenotypes. However, an integrated subclassification scheme demonstrated varying survival probabilities when comparing endophenotypes. Interpretation: Our research underscores the reproducibility of latent profile analyses to identify clinical and biologically informative pediatric septic shock phenotypes with high prognostic relevance. Pending validation, an integrated subclassification scheme, reflective of the different facets of the host response, holds promise to inform targeted intervention among those critically ill.Item Editorial: A new frontier in translational research on autoinflammatory diseases - various aspects of innate immunity on human diseases(Frontiers Media, 2023-01-31) Mukai, Tomoyuki; Ida, Hiroaki; Ueki, Yasuyoshi; Nishikomori, Ryuta; Biomedical Sciences and Comprehensive Care, School of DentistryItem Effects of Soy Peptide on Dendritic Cells(Office of the Vice Chancellor for Research, 2013-04-05) Shipman, Kaylee; Tung, Chun-Yu; Han, Ling; Patel, Amy; Corn, Caleb; Chang, Hua-ChenInnate immunity is mediated by effector cells, including NK cells, dendritic cells (DCs), macrophages, and polymorphonuclear phagocytes, which can respond immediately after activation through receptors encoded by germ-line genes. Innate immune responses represent the first line of defense in immunosurveillance. Interventions that enhance the functions of innate immunity will be an important armamentarium to human health. We recently exploited a natural dietary soy peptide called lunasin to improve the immune functions. The hypothesis was that lunasin peptide has stimulatory effects on immune cells. To test this hypothesis, human peripheral blood mononuclear cells (PBMCs) of healthy donors were stimulated with or without lunasin. We found that lunasin is capable of stimulating DCs to up-regulate chemokines (CCL2, CCL3, and CCL4), cytokines (TNFα and IFNα), and co-stimulatory molecules (CD80, CD86). In addition, lunasin-treated DCs can provide NK with required signals for activation. Taken together, our results support the immunomodulatory activity of soy peptide on DCs, which leads to enhancement of innate immunity.Item Endotoxin Preconditioning Reprograms S1 Tubules and Macrophages to Protect the Kidney(American Society of Nephrology, 2018-01) Hato, Takashi; Zollman, Amy; Plotkin, Zoya; El-Achkar, Tarek M.; Maier, Bernhard F.; Pay, S. Louise; Dube, Shataakshi; Cabral, Pablo; Yoshimoto, Momoko; McClintick, Jeanette; Dagher, Pierre C.; Medicine, School of MedicinePreconditioning with a low dose of endotoxin confers unparalleled protection against otherwise lethal models of sepsis. The mechanisms of preconditioning have been investigated extensively in isolated immune cells such as macrophages. However, the role of tissue in mediating the protective response generated by preconditioning remains unknown. Here, using the kidney as a model organ, we investigated cell type-specific responses to preconditioning. Compared with preadministration of vehicle, endotoxin preconditioning in the cecal ligation and puncture mouse model of sepsis led to significantly enhanced survival and reduced bacterial load in several organs. Furthermore, endotoxin preconditioning reduced serum levels of proinflammatory cytokines, upregulated molecular pathways involved in phagocytosis, and prevented the renal function decline and injury induced in mice by a toxic dose of endotoxin. The protective phenotype involved the clustering of macrophages around S1 segments of proximal tubules, and full renal protection required both macrophages and renal tubular cells. Using unbiased S1 transcriptomic and tissue metabolomic approaches, we identified multiple protective molecules that were operative in preconditioned animals, including molecules involved in antibacterial defense, redox balance, and tissue healing. We conclude that preconditioning reprograms macrophages and tubules to generate a protective environment, in which tissue health is preserved and immunity is controlled yet effective. Endotoxin preconditioning can thus be used as a discovery platform, and understanding the role and participation of both tissue and macrophages will help refine targeted therapies for sepsis.Item Genetically programmed alternative splicing of NEMO mediates an autoinflammatory disease phenotype(The American Society for Clinical Investigation, 2022) Lee, Younglang; Wessel, Alex W.; Xu, Jiazhi; Reinke, Julia G.; Lee, Eries; Kim, Somin M.; Hsu, Amy P.; Zilberman-Rudenko, Jevgenia; Cao, Sha; Enos, Clinton; Brooks, Stephen R.; Deng, Zuoming; Lin, Bin; de Jesus, Adriana A.; Hupalo, Daniel N.; Piotto, Daniela G.P.; Terreri, Maria T.; Dimitriades, Victoria R.; Dalgard, Clifton L.; Holland, Steven M.; Goldbach-Mansky, Raphaela; Siegel, Richard M.; Hanson, Eric P.; Pediatrics, School of MedicineHost defense and inflammation are regulated by the NF-κB essential modulator (NEMO), a scaffolding protein with a broad immune cell and tissue expression profile. Hypomorphic mutations in inhibitor of NF-κB kinase regulatory subunit gamma (IKBKG) encoding NEMO typically present with immunodeficiency. Here, we characterized a pediatric autoinflammatory syndrome in 3 unrelated male patients with distinct X-linked IKBKG germline mutations that led to overexpression of a NEMO protein isoform lacking the domain encoded by exon 5 (NEMO-Δex5). This isoform failed to associate with TANK binding kinase 1 (TBK1), and dermal fibroblasts from affected patients activated NF-κB in response to TNF but not TLR3 or RIG-I-like receptor (RLR) stimulation when isoform levels were high. By contrast, T cells, monocytes, and macrophages that expressed NEMO-Δex5 exhibited increased NF-κB activation and IFN production, and blood cells from these patients expressed a strong IFN and NF-κB transcriptional signature. Immune cells and TNF-stimulated dermal fibroblasts upregulated the inducible IKK protein (IKKi) that was stabilized by NEMO-Δex5, promoting type I IFN induction and antiviral responses. These data revealed how IKBKG mutations that lead to alternative splicing of skipping exon 5 cause a clinical phenotype we have named NEMO deleted exon 5 autoinflammatory syndrome (NDAS), distinct from the immune deficiency syndrome resulting from loss-of-function IKBKG mutations.
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