Conserved γδ T cell selection by BTNL proteins limits progression of human inflammatory bowel disease.

Murine intraepithelial γδ T cells include distinct tissue-protective cells selected by epithelial butyrophilin-like (BTNL) heteromers. To determine whether this biology is conserved in humans, we characterized the colonic γδ T cell compartment, identifying a diverse repertoire that includes a phenotypically distinct subset coexpressing T cell receptor Vγ4 and the epithelium-binding integrin CD103. This subset was disproportionately diminished and dysregulated in inflammatory bowel disease, whereas on-treatment CD103γδ T cell restoration was associated with sustained inflammatory bowel disease remission.

IFN-γ-dependent interactions between tissue-intrinsic γδ T cells and tissue-infiltrating CD8 T cells limit allergic contact dermatitis.

Background: Elicitation of allergic contact dermatitis (ACD), an inflammatory type 4 hypersensitivity disease, induces skin infiltration by polyclonal effector CD8 αβ T cells and precursors of tissue-resident memory T (T) cells. Because T have long-term potential to contribute to body-surface immunoprotection and immunopathology, their local regulation needs a fuller understanding.

Objective: We sought to investigate how T-cell maturation might be influenced by innate-like T cells pre-existing within many epithelia.

DECIDE: Delphi Expert Consensus Statement on Inflammatory Bowel Disease Dysplasia Shared Management Decision-Making.

Background And Aims: Inflammatory bowel disease colitis-associated dysplasia is managed with either enhanced surveillance and endoscopic resection or prophylactic surgery. The rate of progression to cancer after a dysplasia diagnosis remains uncertain in many cases and patients have high thresholds for accepting proctocolectomy. Individualised discussion of management options is encouraged to take place between patients and their multidisciplinary teams for best outcomes.

Adaptations to the British Society of Gastroenterology guidelines on the management of acute severe UC in the context of the COVID-19 pandemic: a RAND appropriateness panel.

Objective: Management of acute severe UC (ASUC) during the novel COVID-19 pandemic presents significant dilemmas. We aimed to provide COVID-19-specific guidance using current British Society of Gastroenterology (BSG) guidelines as a reference point.

Design: We convened a RAND appropriateness panel comprising 14 gastroenterologists and an IBD nurse consultant supplemented by surgical and COVID-19 experts.

British Society of Gastroenterology guidance for management of inflammatory bowel disease during the COVID-19 pandemic.

The COVID-19 pandemic is putting unprecedented pressures on healthcare systems globally. Early insights have been made possible by rapid sharing of data from China and Italy. In the UK, we have rapidly mobilised inflammatory bowel disease (IBD) centres in order that preparations can be made to protect our patients and the clinical services they rely on.

The γδTCR combines innate immunity with adaptive immunity by utilizing spatially distinct regions for agonist selection and antigen responsiveness.

T lymphocytes expressing γδ T cell antigen receptors (TCRs) comprise evolutionarily conserved cells with paradoxical features. On the one hand, clonally expanded γδ T cells with unique specificities typify adaptive immunity. Conversely, large compartments of γδTCR intraepithelial lymphocytes (γδ IELs) exhibit limited TCR diversity and effect rapid, innate-like tissue surveillance.

Optimising use of thiopurines in inflammatory bowel disease.

Thiopurines are central to inflammatory bowel disease (IBD) therapeutics, either as monotherapy or in combination with newer biologic therapies, however it is only recently that focus has increased on improving effectiveness and tolerability through optimisation. Areas covered: We review the role of thiopurines in IBD and the importance of the timing of initiation of therapy. Drug metabolism and pharmacogenetics have increasingly played a role in determining dosing and dose optimisation and we review the rationale for this in both thiopurine monotherapy and in combination with biologic agents.

Vedolizumab: toward a personalized therapy paradigm for people with ulcerative colitis.

Ulcerative colitis (UC) is a chronic relapsing and remitting inflammatory bowel disease, with a characteristic leukocytic infiltration of the mucosa. Immunosuppression including anti-TNF-α therapy is a mainstay of treatment for many; however, systemic immunosuppression is not universally effective and is associated with potential side effects. The gut-tropic integrin α4β7, which is expressed on leukocytes, mediates migration from the circulation to the intestinal mucosa.

Epithelia Use Butyrophilin-like Molecules to Shape Organ-Specific γδ T Cell Compartments.

Many body surfaces harbor organ-specific γδ T cell compartments that contribute to tissue integrity. Thus, murine dendritic epidermal T cells (DETCs) uniquely expressing T cell receptor (TCR)-Vγ5 chains protect from cutaneous carcinogens. The DETC repertoire is shaped by Skint1, a butyrophilin-like (Btnl) gene expressed specifically by thymic epithelial cells and suprabasal keratinocytes.

Conjunctival interleukin-13 expression in mucous membrane pemphigoid and functional effects of interleukin-13 on conjunctival fibroblasts in vitro.

Interleukin-13 (IL-13) is the dominant effector cytokine of fibrosis in pulmonary and liver disease. Excessive conjunctival fibrosis in the immunobullous disease ocular mucous membrane pemphigoid (MMP) causes blindness; the pathogenesis of scarring in this disease is incompletely understood. To determine whether IL-13 is involved in conjunctival fibrosis in MMP, we studied the expression of IL-13 in ocular MMP patients before and after systemic immunosuppression and examined the effects of IL-13 on normal human conjunctival fibroblasts.

Tumor necrosis factor-alpha in ocular mucous membrane pemphigoid and its effect on conjunctival fibroblasts.

Purpose: First, to determine whether tumor necrosis factor-(TNF)-alpha is expressed in the conjunctiva of ocular mucous membrane pemphigoid (MMP) and the consequences of systemic immunosuppressive treatment on this expression. Second, to investigate the in vitro effects of TNFalpha on human conjunctival fibroblasts.

Methods: The expression of TNFalpha in conjunctival tissues of patients with actively inflamed ocular MMP (n = 10), patients with clinically noninflamed ocular MMP after systemic immunosuppressive treatment (n = 10), and normal subjects (n = 10) was studied by immunohistochemistry.