Anti–GM-CSF autoantibodies promote a “pre-diseased” state in Crohn’s Disease

AbstractBackground & AimsAnti–GM-CSF autoantibodies (aGMAb) are detected in ileal Crohn’s Disease (CD) patients. Their induction and mode of action impacting homeostasis during, or prior to disease are not well understood. We aimed to investigate the underlying mechanisms leading to the induction of aGMAb, from functional orientation to recognized epitopes, for their impact on intestinal immune homeostasis and use as predictive biomarker for complicated CD.MethodsUsing longitudinally collected sera from active component US personnel, we characterize naturally occurring aGMAb in a subset of CD patients years before disease onset. We employed biochemical, cellular, and transcriptional analysis to uncover a mechanism that governs the impaired immune balance in CD years prior to diagnosis.ResultsNeutralizing aGMAb are specific to posttranslational glycosylations on GM-CSF, detectable years prior to diagnosis, and associated with complicated CD at presentation. Glycosylation and production of GM-CSF change in CD patients, altering myeloid homeostasis and destabilizing group 3 innate lymphoid cells. Perturbations in immune homeostasis precede the inflammation and are detectable in the non-inflamed CD mucosa of patients presenting with anti-GM-CSF autoantibodies.ConclusionsAnti-GM-CSF autoantibodies predict the diagnosis of complicated CD, have unique epitopes, and impair myeloid cell homeostasis across the ILC3-GM-CSF-myeloid cell axis, altering intestinal immune homeostasis long before the diagnosis of disease.

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A5 GM-CSF AUTOANTIBODIES: PREDICTORS OF CROHN’S DISEASE DEVELOPMENT AND A NOVEL THERAPEUTIC APPROACH

Journal of the Canadian Association of Gastroenterology ◽

10.1093/jcag/gwab002.004 ◽

2021 ◽

Vol 4 (Supplement_1) ◽

pp. 5-6

Author(s):

S Tai ◽

R Remark ◽

I Laface ◽

D M Del Valle ◽

J Torres ◽

...

Keyword(s):

Crohn’S Disease ◽

Crohn's Disease ◽

Neutralizing Antibodies ◽

Mononuclear Cells ◽

Immune Cell ◽

Disease Diagnosis ◽

Mononuclear Phagocytes ◽

Lymphoid Cells ◽

Inflammatory Disorder ◽

Gm Csf

Abstract Background Crohn’s disease (CD) is a heterogenous, chronic inflammatory disorder driven by a combination of genetic, environmental, and microbiota-dependent risk factors. Mononuclear phagocytes (MNP) are crucial cells that maintain intestinal homeostasis. An important cytokine for MNP survival and function is granulocyte-macrophage colony stimulating factor (GM-CSF). Interestingly, several studies reported CD-associated genetic risk variants within the GM-CSF receptor and its downstream signaling components. Furthermore, high titers of autoantibodies specific to GM-CSF can be detected in CD patients. Taken together, this data suggests an important role for GM-CSF in abrogation of CD development in a subgroup of patients. Aims This study sought to investigate the function of GM-CSF autoantibodies in CD. Methods We retrospectively quantified and characterized GM-CSF autoantibodies in sera of 220 CD, 200 ulcerative colitis (UC) patients, and 220 healthy controls (HC) sampled at 3 time points prior to disease diagnosis and one time point after diagnosis. ELISA was used to determine GM-CSF autoantibody titers and isotypes followed by in vitro multiplexed mass cytometry (CyTOF) neutralization assays on peripheral blood mononuclear cells. Flow cytometry and CyTOF were used to map the profile of immune cells isolated from inflamed and non-inflamed CD mucosa. Results Our data demonstrates that GM-CSF autoantibodies are specific to CD, significantly elevated up to 7 years prior to diagnosis of disease, and correlate with disease location, severity, and complications at the time of diagnosis. Moreover, in contrast to GM-CSF autoantibodies in pulmonary alveolar proteinosis patients, CD-associated autoantibodies neutralize GM-CSF via specific recognition of post-translational modifications (PTM), affecting MNP function. Removal of PTM enabled GM-CSF to escape autoantibody binding and restored MNP response to GM-CSF in the presence of neutralizing antibodies, indicating a potential therapeutic avenue. Furthermore, we identified group 3 innate lymphoid cells (ILC3) as a major source of GM-CSF in the healthy intestinal tract, suggesting intriguing crosstalk of MNP and ILC3 across the GM-CSF-GM-CSFR axis. Conclusions Our results identify GM-CSF autoantibodies as predictive serological biomarker for CD in a subgroup of patients presenting with severe and complicated form of disease at the time of diagnosis. The presence of GM-CSF autoantibodies precedes the onset of CD by several years and likely abrogates homeostatic immune cell crosstalk involving ILC3 and MNP, suggesting the development of a pre-diseased state in CD patients. Funding Agencies CIHRDr. Edward Ketchum Graduate Scholarship

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P064 Identification of inflammatory mediators in Crohn's disease patients who are unresponsive to anti-TNF therapy – A transcriptional analysis of intestinal mucosa

Journal of Crohn s and Colitis ◽

10.1016/s1873-9946(14)60186-0 ◽

2014 ◽

Vol 8 ◽

pp. S89

Author(s):

R.F. Leal ◽

N. Planell ◽

R. Kajekar ◽

J.J. Lozano ◽

I. Ordás ◽

...

Keyword(s):

Crohn’S Disease ◽

Crohn's Disease ◽

Intestinal Mucosa ◽

Inflammatory Mediators ◽

Transcriptional Analysis

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Debaryomyces is enriched in Crohn’s disease intestinal tissue and impairs healing in mice

Science ◽

10.1126/science.abd0919 ◽

2021 ◽

Vol 371 (6534) ◽

pp. 1154-1159 ◽

Cited By ~ 1

Author(s):

Umang Jain ◽

Aaron M. Ver Heul ◽

Shanshan Xiong ◽

Martin H. Gregory ◽

Elora G. Demers ◽

...

Keyword(s):

Crohn’S Disease ◽

Crohn's Disease ◽

Human Subjects ◽

Debaryomyces Hansenii ◽

Myeloid Cell ◽

Mucosal Healing ◽

Mucosal Tissues ◽

Colonic Healing ◽

Gnotobiotic Mice

Alterations of the mycobiota composition associated with Crohn’s disease (CD) are challenging to link to defining elements of pathophysiology, such as poor injury repair. Using culture-dependent and -independent methods, we discovered that Debaryomyces hansenii preferentially localized to and was abundant within incompletely healed intestinal wounds of mice and inflamed mucosal tissues of CD human subjects. D. hansenii cultures from injured mice and inflamed CD tissues impaired colonic healing when introduced into injured conventionally raised or gnotobiotic mice. We reisolated D. hansenii from injured areas of these mice, fulfilling Koch’s postulates. Mechanistically, D. hansenii impaired mucosal healing through the myeloid cell–specific type 1 interferon–CCL5 axis. Taken together, we have identified a fungus that inhabits inflamed CD tissue and can lead to dysregulated mucosal healing.

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Immune system alterations in patients with inflammatory bowel disease during remission

Medicina ◽

10.3390/medicina44010005 ◽

2008 ◽

Vol 44 (1) ◽

pp. 27 ◽

Cited By ~ 14

Author(s):

Jurgita Šventoraitytė ◽

Aida Žvirblienė ◽

Gediminas Kiudelis ◽

Rimantas Žalinkevičius ◽

Aurelija Žvirblienė ◽

...

Keyword(s):

Ulcerative Colitis ◽

Inflammatory Bowel Disease ◽

Crohn’S Disease ◽

Crohn's Disease ◽

Bowel Disease ◽

Immune Homeostasis ◽

Th2 Cytokines ◽

Inflammatory Bowel ◽

Anti Inflammatory ◽

And Control

Objective. Perturbed immune homeostasis elicited by misbalanced production of proinflammatory and anti-inflammatory cytokines is characteristic of inflammatory bowel disease. The aim of this study was to evaluate cytokine profile in patients with different forms of inflammatory bowel disease – ulcerative colitis and Crohn’s disease – during clinical remission phase. Material and methods. Production of proinflammatory Th1 cytokines (tumor necrosis factoralpha (TNF-a), interferon-gamma (IFN-g)) and anti-inflammatory Th2 cytokines (interleukin- 10 (IL-10) and interleukin-13 (IL-13)) was analyzed in peripheral blood mononuclear cells of patients with inflammatory bowel disease (9 with ulcerative colitis and 9 with Crohn’s disease) and control subjects (n=11) by enzyme-linked immunosorbent assay (two-site ELISA). Results. The results of the study revealed that the level of TNF-a after stimulation with phytohemagglutinin in patients with Crohn’s disease was significantly higher in comparison to both patients with ulcerative colitis and controls (P<0.001 and P<0.01, respectively). The secretion of IFN-g both in patients with Crohn’s disease and ulcerative colitis was lower than that in controls (P=0.05 and P<0.01, respectively), but it normalized after stimulation with phytohemagglutinin. The levels of IL-10 and IL-13 were significantly (P<0.01) higher in patients with Crohn’s disease than in patients with ulcerative colitis and control group before and after stimulation with phytohemagglutinin. Conclusions. The results of our study provide evidence that in patients with inflammatory bowel disease, the imbalance between production of proinflammatory Th1 and anti-inflammatory Th2 cytokines persists even during remission of the disease, and disturbances of immune homeostasis are significantly more expressed in patients with Crohn’s disease than in patients with ulcerative colitis.

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398 THE GEM PROJECT: IDENTIFICATION OF A SERUM PROTEOMIC SIGNATURE ASSOCIATED WITH RISK OF FUTURE CROHN'S DISEASE ONSET IN A COHORT OF HEALTHY AT-RISK INDIVIDUALS

Gastroenterology ◽

10.1016/s0016-5085(20)30864-7 ◽

2020 ◽

Vol 158 (6) ◽

pp. S-73

Author(s):

Juan Antonio Raygoza Garay ◽

Williams Turpin ◽

Michelle I. Smith ◽

Ashleigh Goethel ◽

Hien Q. Huynh ◽

...

Keyword(s):

At Risk ◽

Crohn’S Disease ◽

Crohn's Disease ◽

Disease Onset

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STAT3 Genotypic Variant rs744166 and Increased Tyrosine Phosphorylation of STAT3 in IL-23 Responsive Innate Lymphoid Cells during Pathogenesis of Crohn’s Disease

Journal of Immunology Research ◽

10.1155/2019/9406146 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Ying Tang ◽

Sanda A. Tan ◽

Atif Iqbal ◽

Jian Li ◽

Sarah C. Glover

Keyword(s):

Crohn’S Disease ◽

Crohn's Disease ◽

Immune Responses ◽

Tyrosine Phosphorylation ◽

Innate Lymphoid Cells ◽

Immune Defense ◽

Lymphoid Cells ◽

Dependent Manner ◽

Regulatory Pathways ◽

Innate Effector

Crohn’s disease (CD) results from dysregulated immune responses to gut microbiota in genetically susceptible individuals, affecting multiple areas of the gastrointestinal tract. Innate lymphoid cells (ILCs) are tissue-resident innate effector lymphocytes which play crucial roles in mucosal immune defense, tissue repair, and maintenance of homeostasis. The accumulation of IFN-γ-producing ILC1s and increased level of proinflammatory cytokines produced by ILCs has been observed in the inflamed terminal ileum of CD patients. To date, the precise mechanisms of ILC plasticity and gene regulatory pathways in ILCs remain unclear. Signal transducer and activator of transcription 3 (STAT3) regulates gene expression in a cell-specific, cytokine-dependent manner, involving multiple immune responses. This study proposes the positive correlation between the prevalence of STAT3 rs744166 risky allele “A” with the severity of disease in a cohort of 94 CD patients. In addition, the results suggest an increased STAT3 activity in the inflamed ileum of CD patients, compared to unaffected ileum sections. Notably, IL-23 triggers the differentiation of CD117+NKp44- ILC3s and induces the activation of STAT3 in both CD117+NKp44- and CD117-NKp44- ILC subsets, implying the involvement of STAT3 in the initiation of ILC plasticity. Moreover, carriage of STAT3 “A” risk allele exhibited a higher basal level of STAT3 tyrosine phosphorylation, and an increased IL-23 triggered the pSTAT3 level. We also demonstrated that there was no delayed dephosphorylation of STAT3 in ILCs of both A/A and G/G donors. Overall, the results of this study suggest that IL-23-induced activation of STAT3 in the CD117-NKp44- ILC1s involves in ILC1-to-ILC3 plasticity and a potential regulatory role of ILC1 function. Those genetically susceptible individuals carried STAT3 rs744166 risky allele appear to have higher basal and cytokine-stimulated activation of STAT3 signal, leading to prolonged inflammation and chronic relapse.

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