1. Histamine drives severity of innate inflammation via histamine 4 receptor in murine experimental colitis
- Author
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Roderick Carter, Terrence A. Barrett, Rebecca A. Krier-Burris, Tania E. Velez, Ming Y. Wang, Chia-Lin Hsu, Jeffrey B. Brown, Mendy L. Miller, Joshua B. Wechsler, Alison Szabo, Barry K. Wershil, Lizath M. Aguiniga, Holly A. Schroeder, and Paul J. Bryce
- Subjects
Male ,0301 basic medicine ,colitis ,Histidine Decarboxylase ,Mice ,Histamine receptor ,chemistry.chemical_compound ,neutrophils ,histamine 4 receptor ,Immunology and Allergy ,Mast Cells ,Intestinal Mucosa ,Receptor ,Cells, Cultured ,Mice, Knockout ,Dextran Sulfate ,Middle Aged ,Mast cell ,3. Good health ,CXCL1 ,medicine.anatomical_structure ,Neutrophil Infiltration ,Female ,medicine.symptom ,Histamine ,Adult ,Adolescent ,Colon ,Immunology ,Inflammation ,Granulocyte ,Article ,Young Adult ,03 medical and health sciences ,medicine ,Animals ,Humans ,Colitis ,Aged ,Receptors, Histamine H4 ,business.industry ,Oxazolone ,medicine.disease ,histamine ,Mice, Inbred C57BL ,Disease Models, Animal ,030104 developmental biology ,chemistry ,Colitis, Ulcerative ,business - Abstract
Ulcerative colitis (UC) patients exhibit elevated histamine, but how histamine exacerbates disease is unclear as targeting histamine 1 receptor (H1R) or H2R is clinically ineffective. We hypothesized that histamine functioned instead through the other colon-expressed histamine receptor, H4R. In humans, UC patient biopsies exhibited increased H4R RNA and protein expression over control tissue, and immunohistochemistry showed that H4R was in proximity to immunopathogenic myeloperoxidase-positive neutrophils. To characterize this association further, we employed both the oxazolone (Ox)- and dextran sulfate sodium (DSS)-induced experimental colitis mouse models and also found upregulated H4R expression. Mast cell (MC)-derived histamine and H4R drove experimental colitis, as H4R-/- mice had lower symptom scores, neutrophil-recruitment mediators (colonic interleukin-6 (IL-6), CXCL1, CXCL2), and mucosal neutrophil infiltration than wild-type (WT) mice, as did MC-deficient KitW-sh/W-sh mice reconstituted with histidine decarboxylase-deficient (HDC-/-) bone marrow-derived MCs compared with WT-reconstituted mice; adaptive responses remained intact. Furthermore, Rag2-/- × H4R-/- mice had reduced survival, exacerbated colitis, and increased bacterial translocation than Rag2-/- mice, revealing an innate protective antibacterial role for H4R. Taken together, colonic MC-derived histamine initiates granulocyte infiltration into the colonic mucosa through H4R, suggesting alternative therapeutic targets beyond adaptive immunity for UC.
- Published
- 2018
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