Bana Jabri

University of Chicago, Chicago, Illinois, United States

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Publications (84)1073.63 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Eicosanoids are inflammatory mediators that play a key but incompletely understood role in linking the innate and adaptive immune systems. Here, we show that cytotoxic effector T cells (CTLs) are capable of both producing and responding to cysteinyl leukotrienes (CystLTs), allowing for the killing of target cells in a T cell receptor-independent manner. This process is dependent on the natural killer receptor NKG2D and exposure to IL-15, a cytokine induced in distressed tissues. IL-15 and NKG2D signaling drives the up-regulation of key enzymes implicated in the synthesis of CystLTs, as well as the expression of CystLT receptors, suggesting a positive feedback loop. Finally, although the CystLT pathway has been previously linked to various allergic disorders, we provide unexpected evidence for its involvement in the pathogenesis of celiac disease (CD), a T helper 1 cell-mediated enteropathy induced by gluten. These findings provide new insights into the cytolytic signaling pathway of NKG2D and the pathogenesis of organ-specific immune disorders. Furthermore, they suggest that the blockade of CystLT receptors may represent a potent therapeutic target for CD or potentially other autoimmune disorders in which NKG2D has been implicated. © 2015 Tang et al.
    Journal of Experimental Medicine 08/2015; DOI:10.1084/jem.20150303 · 12.52 Impact Factor
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    ABSTRACT: Immunoglobulin A (IgA) is prominently secreted at mucosal surfaces and coats a fraction of the intestinal microbiota. However, the commensal bacteria bound by IgA are poorly characterized and the type of humoral immunity they elicit remains elusive. We used bacterial flow cytometry coupled with 16S rRNA gene sequencing (IgA-Seq) in murine models of immunodeficiency to identify IgA-bound bacteria and elucidate mechanisms of commensal IgA targeting. We found that residence in the small intestine, rather than bacterial identity, dictated induction of specific IgA. Most commensals elicited strong T-independent (TI) responses that originated from the orphan B1b lineage and from B2 cells, but excluded natural antibacterial B1a specificities. Atypical commensals including segmented filamentous bacteria and Mucispirillum evaded TI responses but elicited T-dependent IgA. These data demonstrate exquisite targeting of distinct commensal bacteria by multiple layers of humoral immunity and reveal a specialized function of the B1b lineage in TI mucosal IgA responses. Copyright © 2015 Elsevier Inc. All rights reserved.
    Immunity 08/2015; DOI:10.1016/j.immuni.2015.08.007 · 21.56 Impact Factor
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    ABSTRACT: Several studies point towards alteration in gut microbiota composition and function in coeliac disease, some of which can precede the onset of disease and/or persist when patients are on a gluten-free diet. Evidence also exists that the gut microbiota might promote or reduce coeliac-disease-associated immunopathology. However, additional studies are required in humans and in mice (using gnotobiotic technology) to determine cause-effect relationships and to identify agents for modulating the gut microbiota as a therapeutic or preventative approach for coeliac disease. In this Review, we summarize the current evidence for altered gut microbiota composition in coeliac disease and discuss how the interplay between host genetics, environmental factors and the intestinal microbiota might contribute to its pathogenesis. Moreover, we highlight the importance of utilizing animal models and long-term clinical studies to gain insight into the mechanisms through which host-microbial interactions can influence host responses to gluten.
    Nature Reviews Gastroenterology &#38 Hepatology 06/2015; 12(9). DOI:10.1038/nrgastro.2015.90 · 12.61 Impact Factor
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    ABSTRACT: Background & aims: The mechanisms of tissue destruction during progression of celiac disease are poorly defined. It is not clear how tissue stress and adaptive immunity contribute to the activation of intraepithelial cytotoxic T cells and the development of villous atrophy. We analyzed epithelial cells and intraepithelial cytotoxic T cells in family members of patients with celiac disease, who were without any signs of adaptive antigluten immunity, and in potential celiac disease patients, who have antibodies against tissue transglutaminase 2 in the absence of villous atrophy. Methods: We collected blood and intestinal biopsy specimens from 268 patients at tertiary medical centers in the United States and Italy from 2004 to 2012. All subjects had normal small intestinal histology. Study groups included healthy individuals with no family history of celiac disease or antibodies against tissue transglutaminase 2 (controls), healthy family members of patients with celiac disease, and potential celiac disease patients. Intraepithelial cytotoxic T cells were isolated and levels of inhibitory and activating natural killer (NK) cells were measured by flow cytometry. Levels of heat shock protein (HSP) and interleukin 15 were measured by immunohistochemistry, and ultrastructural alterations in intestinal epithelial cells (IECs) were assessed by electron microscopy. Results: IECs from subjects with a family history of celiac disease, but not from subjects who already had immunity to gluten, expressed higher levels of HS27, HSP70, and interleukin-15 than controls; their IECs also had ultrastructural alterations. Intraepithelial cytotoxic T cells from relatives of patients with celiac disease expressed higher levels of activating NK receptors than cells from controls, although at lower levels than patients with active celiac disease, and without loss of inhibitory receptors for NK cells. Intraepithelial cytotoxic T cells from potential celiac disease patients failed to up-regulate activating NK receptors. Conclusions: A significant subset of healthy family members of patients with celiac disease with normal intestinal architecture had epithelial alterations, detectable by immunohistochemistry and electron microscopy. The adaptive immune response to gluten appears to act in synergy with epithelial stress to allow intraepithelial cytotoxic T cells to kill epithelial cells and induce villous atrophy in patients with active celiac disease.
    Gastroenterology 05/2015; 149(3). DOI:10.1053/j.gastro.2015.05.013 · 16.72 Impact Factor
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    ABSTRACT: Celiac disease is a T cell mediated immune disorder characterized by the loss of oral tolerance to dietary gluten and the licensing of intraepithelial lymphocytes to kill intestinal epithelial cells, leading to villous atrophy. Innate immunity plays a critical role in both of these processes and cytokines such as interleukin-15 and interferon-α can modulate innate processes such as polarization of dendritic cells as well as intraepithelial lymphocyte function. These cytokines can be modulated by host microbiota, which can also influence dendritic cell function and intraepithelial lymphocyte homeostasis. We will elaborate on the role of interleukin-15, interferon-α, and the microbiota in modulating the processes that lead to loss of tolerance to gluten and tissue destruction in celiac disease. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Baillière&#x027 s Best Practice and Research in Clinical Gastroenterology 05/2015; 29(3). DOI:10.1016/j.bpg.2015.05.001 · 3.48 Impact Factor
  • Bana Jabri · Cox Terhorst
    Current Opinion in Immunology 11/2014; 31C:v-vii. DOI:10.1016/j.coi.2014.10.010 · 7.48 Impact Factor
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    ABSTRACT: The origin and developmental pathway of intestinal T cell receptor αβ(+) CD4(-)CD8β(-) intraepithelial lymphocytes (unconventional iIELs), a major population of innate-like resident cytolytic T cells, have remained elusive. By cloning and expressing several TCRs isolated from unconventional iIELs, we identified immature CD4(lo)CD8(lo)(DP(lo))CD69(hi)PD-1(hi) thymocytes as the earliest postsignaling precursors for these cells. Although these precursors displayed multiple signs of elevated TCR signaling, a sizeable fraction of them escaped deletion to selectively engage in unconventional iIEL differentiation. Conversely, TCRs cloned from DP(lo)CD69(hi)PD-1(hi) thymocytes, a population enriched in autoreactive thymocytes, selectively gave rise to unconventional iIELs upon transgenic expression. Thus, the unconventional iIEL precursor overlaps with the DP(lo) population undergoing negative selection, indicating that, concomitant with the downregulation of both CD4 and CD8 coreceptors, a balance between apoptosis and survival signals results in outcomes as divergent as clonal deletion and differentiation to the unconventional iIEL lineage.
    Immunity 08/2014; 41(2). DOI:10.1016/j.immuni.2014.07.008 · 21.56 Impact Factor
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    ABSTRACT: Background and aim: Isotretinoin, a vitamin A analogue, can promote a pro-inflammatory milieu in the small intestine in response to dietary antigens. We hypothesized that oral isotretinoin exposure would increase the risk of celiac disease (CD). Methods: We contacted all 28 pathology departments in Sweden, and through biopsy reports identified 26,739 individuals with CD. We then compared the prevalence of ever using oral isotretinoin to the prevalence in 134,277 matched controls through conditional logistic regression. Data on isotretinoin exposure were obtained from the national Swedish Prescribed Drug Registry. As the only indication for isotretinoin use in Sweden is acne, we also examined its relationship to CD. Data on acne were obtained from the Swedish Patient Registry. Results: Ninety-three individuals with CD (0.35 %) and 378 matched controls (0.28 %) had a prescription of isotretinoin. This corresponded to an odds ratio (OR) of 1.22 [95 % confidence interval (CI) 0.97-1.54]. Risk estimates were similar in men and women, and when we restricted our data to individuals diagnosed after the start of the Prescribed Drug Registry. Restricting our analyses to individuals diagnosed aged 12-45 years did not influence the risk estimates (OR 1.38, 95 % CI 0.97-1.97). Meanwhile, having a diagnosis of acne was positively associated with CD (OR 1.34, 95 % CI 1.20-1.51). Conclusions: This study found no association between isotretinoin use and CD, but a small excess risk of CD in patients with a diagnosis of acne.
    American Journal of Clinical Dermatology 07/2014; 15(6). DOI:10.1007/s40257-014-0090-8 · 2.73 Impact Factor
  • Valérie Abadie · Bana Jabri
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    ABSTRACT: Interleukin-15 (IL-15) exerts many biological functions essential for the maintenance and function of multiple cell types. Although its expression is tightly regulated, IL-15 upregulation has been reported in many organ-specific autoimmune disorders. In celiac disease, an intestinal inflammatory disorder driven by gluten exposure, the upregulation of IL-15 expression in the intestinal mucosa has become a hallmark of the disease. Interestingly, because it is overexpressed both in the gut epithelium and in the lamina propria, IL-15 acts on distinct cell types and impacts distinct immune components and pathways to disrupt intestinal immune homeostasis. In this article, we review our current knowledge of the multifaceted roles of IL-15 with regard to the main immunological processes involved in the pathogenesis of celiac disease.
    Immunological Reviews 07/2014; 260(1):221-34. DOI:10.1111/imr.12191 · 10.12 Impact Factor
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    ABSTRACT: The NKG2 family of NK receptors includes activating and inhibitory members. With the exception of the homodimer-forming NKG2D, NKG2 receptors recognize the nonclassical MHC class I molecule HLA-E, and they can be subdivided into two groups: those that associate with and signal through DAP12 to activate cells, and those that contain an ITIM motif to promote inhibition. The function of NKG2 family member NKG2E is unclear in humans, and its surface expression has never been conclusively established, largely because there is no Ab that binds specifically to NKG2E. Seeking to determine a role for this molecule, we chose to investigate its expression and ability to form complexes with intracellular signaling molecules. We found that NKG2E was capable of associating with CD94 and DAP12 but that the complex was retained intracellularly at the endoplasmic reticulum instead of being expressed on cell surfaces, and that this localization was dependent on a sequence of hydrophobic amino acids in the extracellular domain of NKG2E. Because this particular sequence has emerged and been conserved selectively among higher order primates evolutionarily, this observation raises the intriguing possibility that NKG2E may function as an intracellular protein.
    The Journal of Immunology 06/2014; 193(2). DOI:10.4049/jimmunol.1400556 · 4.92 Impact Factor
  • Bana Jabri · Xi Chen · Ludvig M Sollid
    Nature Structural & Molecular Biology 04/2014; 21(5). DOI:10.1038/nsmb.2826 · 13.31 Impact Factor
  • Journal of Surgical Research 02/2014; 186(2):591. DOI:10.1016/j.jss.2013.11.544 · 1.94 Impact Factor
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    ABSTRACT: Antibiotic resistance among highly pathogenic strains of bacteria and fungi is a growing concern in the face of the ability to sustain life during critical illness with advancing medical interventions. The longer patients remain critically ill, the more likely they are to become colonized by multidrug-resistant (MDR) pathogens. The human gastrointestinal tract is the primary site of colonization of manyMDR pathogens and is a major source of life-threatening infections due to these microorganisms. Eradication measures to sterilize the gut are difficult if not impossible and carry the risk of further antibiotic resistance. Here, we present a strategy to contain rather than eliminateMDRpathogens by using an agent that interferes with the ability of colonizing pathogens to express virulence in response to hostderived and local environmental factors. The antivirulence agent is a phosphorylated triblock high-molecular-weight polymer (here termed Pi-PEG 15-20) that exploits the known properties of phosphate (Pi) and polyethylene glycol 15-20 (PEG 15-20) to suppress microbial virulence and protect the integrity of the intestinal epithelium. The compound is nonmicrobiocidal and appears to be highly effective when tested both in vitro and in vivo. Structure functional analyses suggest that the hydrophobic bis-aromatic moiety at the polymer center is of particular importance to the biological function of Pi-PEG 15-20, beyond its phosphate content. Animal studies demonstrate that Pi-PEG prevents mortality in mice inoculated with multiple highly virulent pathogenic organisms from hospitalized patients in association with preservation of the core microbiome. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
    Antimicrobial Agents and Chemotherapy 02/2014; 58(2). DOI:10.1128/AAC.02183-13 · 4.48 Impact Factor
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    ABSTRACT: The nature of the antigens recognized by γδ T cells and their potential recognition of major histocompatibility complex (MHC)-like molecules has remained unclear. Members of the CD1 family of lipid-presenting molecules are suggested ligands for Vδ1 TCR-expressing γδ T cells, the major γδ lymphocyte population in epithelial tissues. We crystallized a Vδ1 TCR in complex with CD1d and the self-lipid sulfatide, revealing the unusual recognition of CD1d by germline Vδ1 residues spanning all complementarity-determining region (CDR) loops, as well as sulfatide recognition separately encoded by nongermline CDR3δ residues. Binding and functional analysis showed that CD1d presenting self-lipids, including sulfatide, was widely recognized by gut Vδ1+ γδ T cells. These findings provide structural demonstration of MHC-like recognition of a self-lipid by γδ T cells and reveal the prevalence of lipid recognition by innate-like T cell populations.
    Immunity 11/2013; 39(6). DOI:10.1016/j.immuni.2013.11.001 · 21.56 Impact Factor
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    ABSTRACT: NK cells are large granular lymphocytes that form a critical component of the innate immune system, whose functions include the killing of cells expressing stress-induced molecules. It is increasingly accepted that despite being considered prototypical effector cells, NK cells require signals to reach their full cytotoxic potential. We previously showed that IL-15 is capable of arming CD8 effector T cells to kill independently of their TCR via NKG2D in a cPLA2-dependent process. As NK cells also express NKG2D, we wanted to investigate whether this pathway functioned in an analogous manner and if resting NK cells could be primed to the effector phase by IL-15. Furthermore, to establish relevance to human disease we studied a possible role for this pathway in the pathogenesis of psoriatic arthritis, since there are aspects of this disease that suggest a potential effector role for the innate immune system. We found that PsA patients had upregulated IL-15 and MIC in their affected synovial tissues, and that this unique inflammatory environment enabled NK cell activation and killing via NKG2D and cPLA2. Moreover, we were able to reproduce the phenotype of joint NK cells from blood NK cells by incubating them with IL-15. Altogether, these findings suggest a destructive role for NK cells when activated by environmental stress signals during the pathogenesis of PsA and demonstrate that IL-15 is capable of priming resting NK cells in tissues to the effector phase.
    PLoS ONE 09/2013; 8(9):e76292. DOI:10.1371/journal.pone.0076292 · 3.23 Impact Factor
  • Digestive and Liver Disease 09/2013; 45:e277. DOI:10.1016/j.dld.2013.08.169 · 2.96 Impact Factor
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    ABSTRACT: Increased serum levels of IL-15 are reported in type 1 diabetes (T1D). Here we report elevated serum soluble IL-15Rα levels in human T1D. To investigate the role of IL-15/IL-15Rα in the pathogenesis of T1D, we generated double transgenic mice with pancreatic β-cell expression of IL-15 and IL-15Rα. The mice developed hyperglycemia, marked mononuclear cell infiltration, β-cell destruction, and anti-insulin autoantibodies that mimic early human T1D. The diabetes in this model was reversed by inhibiting IL-15 signaling with anti-IL2/IL15Rβ (anti-CD122), which blocks IL-15 transpresentation. Furthermore, the diabetes could be reversed by administration of the Janus kinase 2/3 inhibitor tofacitinib, which blocks IL-15 signaling. In an alternative diabetes model, nonobese diabetic mice, IL15/IL-15Rα expression was increased in islet cells in the prediabetic stage, and inhibition of IL-15 signaling with anti-CD122 at the prediabetic stage delayed diabetes development. In support of the view that these observations reflect the conditions in humans, we demonstrated pancreatic islet expression of both IL-15 and IL-15Rα in human T1D. Taken together our data suggest that disordered IL-15 and IL-15Rα may be involved in T1D pathogenesis and the IL-15/IL15Rα system and its signaling pathway may be rational therapeutic targets for early T1D.
    Proceedings of the National Academy of Sciences 07/2013; 110(33). DOI:10.1073/pnas.1312911110 · 9.67 Impact Factor
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    ABSTRACT: A major challenge of cancer immunotherapy is the persistence and outgrowth of subpopulations that lose expression of the target antigen. IL-15 is a potent cytokine that can promote organ-specific autoimmunity when up-regulated on tissue cells. Here we report that T cells eradicated 2-wk-old solid tumors that expressed IL-15, eliminating antigen-negative cells. In contrast, control tumors that lacked IL-15 expression consistently relapsed. Interestingly, even tumors lacking expression of cognate antigen were rejected when expressing IL-15, indicating that rejection after adoptive T-cell transfer was independent of cognate antigen expression. Nevertheless, the T-cell receptor of the transferred T cells influenced the outcome, consistent with the notion that T-cell receptor activation and effector status determine whether IL-15 can confer lymphokine killer activity-like properties to T cells. The effect was limited to the microenvironment of tumors expressing IL-15; there were no noticeable effects on contralateral tumors lacking IL-15. Taken together, these results indicate that expression of IL-15 in the tumor microenvironment may prevent the escape of antigen loss variants and subsequent tumor recurrence by enabling T cells to eliminate cancer cells lacking cognate antigen expression in a locally restricted manner.
    Proceedings of the National Academy of Sciences 05/2013; 110(20). DOI:10.1073/pnas.1301022110 · 9.67 Impact Factor

Publication Stats

5k Citations
1,073.63 Total Impact Points


  • 2003–2015
    • University of Chicago
      • • Department of Pathology
      • • Committee on Immunology
      • • Department of Medicine
      Chicago, Illinois, United States
    • Columbia University
      New York, New York, United States
  • 2012
    • University of Padova
      Padua, Veneto, Italy
  • 2006–2011
    • University of Illinois at Chicago
      • Department of Pediatrics (Peoria)
      Chicago, Illinois, United States
  • 1999–2002
    • Princeton University
      • Department of Molecular Biology
      Princeton, New Jersey, United States
  • 2001
    • Mount Sinai Medical Center
      New York, New York, United States
  • 2000
    • Université René Descartes - Paris 5
      • Faculty of medicine
      Lutetia Parisorum, Île-de-France, France
  • 1998
    • Hôpital Henri Mondor (Hôpitaux Universitaires Henri Mondor)
      Créteil, Île-de-France, France