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PubMed2006

Contractile activity of lymphatic vessels is altered in the TNBS model of guinea pig ileitis.

The ability of the lymphatic system to actively remove fluid from the interstitium is critical to the resolution of edema. The response of the lymphatics to inflammatory situations is poorly studied, so we examined mesenteric lymphatic contractile activity in the 2,4,6-trinitrobenzenesulfonic acid (TNBS) model of guinea pig ileitis, a well-accepted animal model of intestinal inflammation, by videomicroscopy in vivo and in vitro 1, 3, and 6 days after induction of ileitis. Lymphatic function (diameter, constriction frequency, amplitude of constrictions, and calculated stroke volume and lymph flow rate) of isolated vessels from TNBS-treated guinea pigs were impaired compared with sham-treated controls. The dysfunction was well correlated with the degree of inflammation, with differences reaching significance (P < 0.05) at the highest inflammation-induced damage observed at day 3. In vivo, significantly fewer lymphatics exhibited spontaneous constrictions in TNBS-treated than sham-treated animals. Cyclooxygenase (COX) metabolites were suggested to be involved in this lymphatic dysfunction, since application of nonselective COX inhibitor (10 microM indomethacin) or a combination of COX-1 and COX-2 inhibitors (1 microM SC-560 and 10 microM celecoxib) markedly increased constriction frequency or induced them in lymphatics from TNBS-treated animals in vivo and in vitro. The present results demonstrate that lymphatic contractile function is altered in TNBS-induced ileitis and suggest a role for prostanoids in the lymphatic dysfunction.

Animals↗
PubMed2003

Characteristics of intermittent mitochondrial transport in guinea pig enteric nerve fibers.

Enteric neurons controlling various gut functions are prone to oxidative insults that might damage mitochondria (e.g., intestinal inflammation). To resume local energy supply, mitochondria need to be transported. We used MitoTracker dyes and confocal microscopy to investigate basic characteristics of mitochondrial transport in guinea pig myenteric neurites. During a 10-s observation of 1 mm nerve fiber, on average, three mitochondria were transported at an average speed of 0.41 +/- 0.02 microm/s. Movement patterns were clearly erratic, and velocities were independent of mitochondrial size. The velocity oscillated periodically ( approximately 6 s) but was not consistently affected by structures such as en route boutons, bifurcations, or stationary mitochondria. Also, mitochondria transported in opposite directions did not necessarily affect each others' mobility. Transport was blocked by microtubule disruption (100 microM colchicine), and destabilization (1 microM cytochalasin-D) or stabilization (10 microM phalloidin) of actin filaments, respectively, decreased (0.22 +/- 0.02 microm/s, P < 0.05) or increased (0.53 +/- 0.02 microm/s, P < 0.05) transport speed. Transport was inhibited by TTX (1 microM), and removal of extracellular Ca(2+) (plus 2 mM EGTA) had no effect. However, depletion of intracellular stores (thapsigargin) reduced (to 33%) and slowed the transport significantly (0.18 +/- 0.02 microm/s, P < 0.05), suggesting an important role for stored Ca(2+) in mitochondrial transport. Transport was also reduced (to 21%) by the mitochondrial uncoupler FCCP (1 microM) in a time-dependent fashion and slowed by oligomycin (10 microM). We conclude that mitochondrial transport is remarkably independent of structural nerve fiber properties. We also show that mitochondrial transport is TTX sensitive and speeds up by stabilizing actin and that functional Ca(2+) stores are required for efficient transport.

Actins↗
PubMed2002

TNBS ileitis evokes hyperexcitability and changes in ionic membrane properties of nociceptive DRG neurons.

This study examines whether intestinal inflammation leads to changes in the properties of ion channels in dorsal root ganglia (DRG) neurons. Ileitis was induced by injection of trinitrobenzene sulfonic acid (TNBS), and DRG neurons innervating the ileum were labeled using fast blue. Intracellular recording techniques were used to measure electrophysiological properties of acutely dissociated neurons 12-24 h after dissection. Nociceptive neurons were identified by sensitivity to capsaicin, tetrodotoxin resistance, and size (<30 microm). The action potential threshold in neurons from TNBS-treated animals was reduced by >70% compared with controls (P < 0.001), but the resting membrane potential was unchanged. Cell diameter, input resistance (67%), and action potential upstroke velocity (22%) increased in the TNBS group (P < 0.05). The number of action potentials discharged increased in the TNBS group (P < 0.001), whereas application of 4-aminopyridine to control cells mimicked this effect. This study demonstrates that ileitis induces hyperexcitability in nociceptive DRG neurons and changes in the properties of Na(+) and K(+) channels at the soma, which persist after removal from the inflamed environment.

4-Aminopyridine↗
PubMed2006

Agonists of cannabinoid receptor 1 and 2 inhibit experimental colitis induced by oil of mustard and by dextran sulfate sodium.

Oil of mustard (OM) is a potent neuronal activator that is known to elicit visceral hyperalgesia when given intracolonically, but the full extent to which OM is also proinflammatory in the gastrointestinal tract is not known. We have previously shown that male CD-1 mice given a single administration of 0.5% OM develop a severe colitis that is maximum at day 3 and that gradually lessens until essentially absent by day 14. OM-induced neuronal stimulation is reported to be reduced by cannabinoid agonists, and cannabinoid receptor 1 (CB1R)-/- mice have exacerbated experimental colitis. Therefore, we examined the role of cannabinoids in this OM-induced 3-day model of colitis in CD-1 mice and in a 7-day dextran sulfate sodium (DSS) colitis model in BALB/c mice. In OM colitis, the CB1R-selective agonist ACEA and the CB2R-selective agonist JWH-133 reduced (P < 0.05) colon weight gain (means +/- SE; 82 +/- 13% and 47 +/- 15% inhibition, respectively), colon shrinkage (98 +/- 24% and 42 +/- 12%, respectively), colon inflammatory damage score (49 +/- 11% and 40 +/- 12%, respectively), and diarrhea (58 +/- 12% and 43 +/- 11%, respectively). Histological damage was similarly reduced by these treatments. Likewise, CBR agonists attenuated DSS colitis, albeit at higher doses; ACEA at 10 mg/kg, twice daily, inhibited (P < 0.05) macroscopic and microscopic scores (46 +/- 9% and 63 +/- 7%, respectively); whereas 20 mg/kg, twice daily, of JWH-133 was required to diminish (P < 0.05) macroscopic and microscopic scores (29 +/- 7% and 43 +/- 5%, respectively). CB1R and CB2R immunostaining of colon sections revealed that CB1R in enteric neurons was more intense in colitic vs. control mice; however, CB1R was also increased in the endothelial layer in OM colitis only. CB2R immunostaining was more marked in infiltrated immune cells in OM colitis. These findings validate the OM colitis model with respect to the DSS model and provide strong support to the emerging idea that cannabinoid receptor activation mediates protective mechanisms in experimental colitis. The demonstration of CB1R agonist effects in colitis support the neurogenic nature of the OM-induced colitis model and reinforce the importance of neuronal activation in intestinal inflammation.

Animals↗
PubMed2002

Modulatory effects of estrogen in two murine models of experimental colitis.

The association between oral contraceptives or pregnancy and inflammatory bowel disease is unclear. We investigated whether 17beta-estradiol modulates intestinal inflammation in two models of colitis. Female mice were treated with 17beta-estradiol alone or with tamoxifen, tamoxifen alone, 17 alpha-estradiol, or placebo. Dinitrobenzene sulfonic acid (DNB)- or dextran sodium sulfate (DSS)-induced colitis were assessed macroscopically, histologically, and by myeloperoxidase (MPO) activity. Malondialdehyde and mRNA levels of intercellular adhesion molecule-1 (ICAM-1), interferon-gamma (IFN-gamma), and interleukin-13 (IL-13) were determined. In DNB colitis, 17beta-estradiol alone, but not 17beta-estradiol plus tamoxifen, or 17 alpha-estradiol reduced macroscopic and histological scores, MPO activity and malondialdehyde levels. 17beta-Estradiol also decreased the expression of ICAM-1, IFN-gamma, and IL-13 mRNA levels compared with placebo. In contrast, 17beta-Estradiol increased the macroscopic and histological scores compared with placebo in mice with DSS colitis. These results demonstrate anti-inflammatory and proinflammatory effects of 17beta-estradiol in two different models of experimental colitis. The net modulatory effect most likely reflects a combination of estrogen receptor-mediated effects and antioxidant activity and may explain, in part, conflicting results from clinical trials.

Animals↗
PubMed1994

IL-8 secretion and neutrophil activation by HT-29 colonic epithelial cells.

This study examines the ability of HT-29 human colonic epithelial cells to stimulate neutrophil migration and adhesion. Interleukin-8 (IL-8), a potent neutrophil chemoattractant, was detected in conditioned media from both unstimulated (1.1 ng/ml) and IL-1 beta-stimulated (16.1 ng/ml) HT-29 cultures. Conditioned medium from IL-1 beta-exposed HT-29 cells stimulated neutrophil migration (395% of control, P < 0.01), and this effect was completely inhibited by anti-IL-8 antibody. HT-29 medium also induced shedding of neutrophil L-selectin and increased expression of neutrophil CD11/CD18 adhesion receptors. Coculture of HT-29 cells with human endothelial cell monolayers resulted in increased neutrophil transendothelial migration (169% of control, P < 0.01), which was blocked by both anti-IL-8 and anti-CD18 antibody. Northern hybridization analysis demonstrated increased levels of mRNA for IL-8 and intercellular adhesion molecule-1 (ICAM-1) in cytokine-treated HT-29 cells. Cytokine stimulation of HT-29 monolayers was also associated with increased neutrophil adhesion to these cells. Neutrophil-HT-29 cell adhesion was blocked by monoclonal antibodies to neutrophil CD18 or to ICAM-1 on the HT-29 cells (86% and 56% inhibition, respectively, P < 0.01 for both). These data suggest that IL-8 secretion by activated colonic epithelial cells may contribute to neutrophil extravasation and tissue infiltration in intestinal inflammation.

Blotting, Northern↗
PubMed1997

Expression of insulin-like growth factor I receptors and binding proteins by colonic smooth muscle cells.

We recently demonstrated upregulation of insulin-like growth factor I (IGF-I) binding sites in the smooth muscle layer of inflamed rat colon. The increase in binding sites was due to increased expression of IGF binding proteins (IGFBPs), which modulate the effects of IGF. To further study the role of IGF in the colon, we investigated whether cultured colonic smooth muscle cells (SMC) express IGF-I receptors and IGFBPs. SMC were isolated by collagenase digestion from rat colonic smooth muscle and grown in primary culture. Equilibrium binding experiments using (125)I-labeled IGF-I showed the presence of an IGF-I receptor with a dissociation constant of 1.96 nM and a maximal binding constant of 53,000 receptors/cell. Competition binding studies with IGF-II and insulin, together with chemical cross-linking experiments, corroborated this conclusion. Western ligand blotting of conditioned medium and Northern analysis of total RNA demonstrated that the cells expressed and secreted IGFBP-4, -5, and -3 with molecular masses of 25, 31, and 45 kDa, respectively. These results, together with our in vivo studies in the rat, support a role for IGF in tissue fibrosis and stricture formation during chronic intestinal inflammation.

Animals↗
PubMed2000

Mechanism of glucocorticoid-mediated reversal of inhibition of Cl(-)/HCO(-)(3) exchange during chronic ileitis.

In the normal ileum, coupled NaCl absorption occurs via the dual operation of Na(+)/H(+) and Cl(-)/HCO(-)(3) exchange on the brush-border membrane (BBM) of villus cells. In a rabbit model of chronic small intestinal inflammation we determined the cellular mechanism of inhibition of NaCl absorption and the effect of steroids on this inhibition. Cl(-)/HCO(-)(3) but not Na(+)/H(+) exchange was reduced in the BBM of villus cells during chronic ileitis. Cl(-)/HCO(-)(3) exchange was inhibited secondary to a decrease in the affinity for Cl(-) rather than an alteration in the maximal rate of uptake of Cl(-) (V(max)). Methylprednisolone (MP) stimulated Cl(-)/HCO(-)(3) exchange in the normal ileum by increasing the V(max) of Cl(-) uptake rather than altering affinity for Cl(-). MP reversed the inhibition of Cl(-)/HCO(-)(3) exchange in rabbits with chronic ileitis. However, MP alleviated the Cl(-)/HCO(-)(3) exchange inhibition by restoring the affinity for Cl(-) rather than altering the V(max) of Cl(-) uptake. These data suggest that glucocorticoids mediate the alleviation of Cl(-)/HCO(-)(3) exchange inhibition in chronically inflamed ileum by reversing the same mechanism that was responsible for inhibition of this transporter rather than exerting a direct effect on the transporter itself, as was the case in normal ileum.

Animals↗
PubMed2000

Keratinocyte growth factor-2 (FGF-10) promotes healing of experimental small intestinal ulceration in rats.

Keratinocyte growth factor-2 (KGF-2, repifermin) is a homolog of KGF-1 with epithelial mitogenic activities. We investigated the therapeutic role of KGF-2 in intestinal ulceration and its mechanisms of protection. KGF-2 (0.3-5 mg/kg) was administered before or after induction of small intestinal ulceration by indomethacin (Indo) in prevention and treatment protocols. In acute studies, KGF-2 was injected for up to 7 days before or daily for 5 days after Indo. In a 15-day chronic study, KGF-2 was injected intravenously daily beginning before or 7 days after Indo. Injury was evaluated by blinded macroscopic and microscopic inflammatory scores, epithelial BrdU staining, tissue IL-1beta, PGE(2), and hydroxyproline concentrations, and collagen type I RNA expression. In vitro effects of KGF-2 were evaluated by epithelial cellular proliferation, restitution of wounded monolayers, PGE(2) secretion, and expression of COX-2 and collagen mRNA. Intravenous KGF-2 significantly decreased acute intestinal injury by all parameters and significantly decreased chronic ulceration. Pretreatment, daily infusion, and delayed treatment were effective. KGF-2 promoted in vitro epithelial restitution with only modest effects on epithelial cell proliferation, stimulated COX-2 expression in cultured epithelial cells, and upregulated in vitro and in vivo PGE(2) production. KGF-2 did not affect in vivo fibrosis, although it induced collagen expression in cultured intestinal myofibroblasts. These results suggest that KGF-2 inhibits intestinal inflammation by stimulating epithelial restitution and protective PGs.

Acute Disease↗
PubMed2001

Preventive effects of Bifidobacterium- and Lactobacillus-fermented milk on the development of inflammatory bowel disease in senescence-accelerated mouse P1/Yit strain mice.

BACKGROUND/AIMS: We recently discovered inflammatory bowel disease (IBD) in the ileum and cecum of SAMP1/Yit strain mice under specific pathogen-free (SPF) conditions. To determine the effect of lactic acid bacteria (LAB - Bifidobacterium breve, Bifidobacterium bifidum and Lactobacillus acidophilus)-fermented milk on the prevention of IBD in SAMP1/Yit strain mice, we compared the disease severity on the intestinal inflammation among the group of mice fed saline, unfermented milk or LAB-fermented milk. METHODS: Three-week-old SAMP1/Yit strain mice (n = 72) were subdivided into three groups, that were fed saline, unfermented milk and LAB-fermented milk, respectively. The diets were orally administered daily via a gastric tube. When the mice reached 20 weeks of age, they were sacrificed and the IBD scores were compared among the three groups. RESULTS: Administration of the LAB-fermented milk to SAMP1/Yit strain mice reduced histological injury score, compared with those in saline-treated or unfermented milk-treated SAMP1/Yit strain mice. Ileal tissue weight and myeloperoxidase activity also reduced by treatment of LAB-fermented milk. Moreover, the tissue contents of immunoglobulins such as IgG1 and IgG2a were lower in the inflammatory regions in the SAMP1/Yit strain group fed LAB-fermented milk than that fed saline and unfermented milk. Cytokine-specific ELISA assays indicated the production of T-helper 1 cytokines such as interferon-gamma and tumor necrosis factor-alpha in the culture supernatants of MLN cells in the SAMP1/Yit strain group fed LAB-fermented milk was lower than those fed saline and unfermented milk. On the contrary, the production of interleukin-10 in MLN cells increased by prevention with LAB-fermented milk. CONCLUSION: LAB-fermented milk is beneficial for the treatment of murine IBD and this effect may be modulated through stabilization of the mucosal immunity by LAB.

Aging↗
PubMed2004

Adsorptive granulocyte and monocyte apheresis versus prednisolone in patients with corticosteroid-dependent moderately severe ulcerative colitis.

BACKGROUND/AIM: Active ulcerative colitis (UC) is often associated with increased peripheral granulocytes and monocytes/macrophages which show activation behavior and prolonged survival time. Further, mucosal granulocyte level parallels intestinal inflammation and can predict UC relapse. Accordingly, our aim was to see if adsorptive granulocyte/monocyte apheresis (GMA) can promote remission and spare steroid in patients with steroid-dependent (SD) UC. METHODS: 69 SD patients, at the time of relapse, were randomly assigned to groups I (n = 46) and II (n = 23). The mean dose of prednisolone (PSL) was 12 mg/day/patient, CAI (clinical activity index) 9.2 in both groups. Group I patients were given up to 11 GMA sessions over 10 weeks with Adacolumn; in group II, the mean dose of PSL was increased to 30 mg/day/patient. RESULTS: At week 12, 83% of group I and 65% of group II patients were in remission, CAI in group I was 1.7 (p < 0.001) and in group II, 2.5 (p < 0.001). Further, during the 12 weeks of treatment, the cumulative amount of PSL received per patient was 1,157 mg in group I and 1,938 mg in group II (p = 0.001). CONCLUSIONS: GMA appeared to be an effective adjunct to standard drug therapy of moderately severe UC by promoting remission and sparing steroids.

Adolescent↗
PubMed1983

Ultrastructure of macrophages of the murine Peyer's patch dome.

The ultrastructure of macrophages located in the dome of murine Peyer's patches was examined by transmission electron microscopy. Aggregates of carbon particles as well as numerous other phagocytic and lysosomal inclusions were consistently observed in dome macrophages of carbon-fed mice. Macrophages of both particle-fed and control mice exhibited morphological features of activation. Degenerating macrophages were observed, and evidence is presented that their disintegration involves invasion by other cells. The morphological findings are in accordance with other evidence that the Peyer's patches receive an influx of material from the intestinal lumen. The potential importance of macrophages in the initiation of intestinal inflammations is emphasized.

Animals↗
PubMed1991

Clinical relevance of activity parameters in Crohn's disease estimated by the faecal excretion of 111In-labeled granulocytes.

The fecal excretion of 111In-oxine-labeled autologous granulocytes was determined in 58 patients with Crohn's disease. A representative analysis of the total amount of excreted cells requires a 4-day stool sampling at least in those patients suffering from Crohn's ileitis or ileocolitis. Various laboratory tests (Orosomucoid, alpha 1-antitrypsin, C-reactive protein, erythrocyte sedimentation rate, leukocytes, thrombocytes, albumin, Fe, alpha 1-globulin and alpha 2-globulin) and the van Hees index significantly correlated with this specific estimate of intestinal inflammation, indicating that it is of little importance which one is clinically used for the assessment of inflammatory activity in Crohn's disease.

Adult↗
PubMed1997

Role of cytokines in experimental colitis: relation to intestinal permeability.

There is now clear evidence supporting the role of cytokines in the clinical and immunopathological manifestations of human inflammotory bowel disease. The purpose of the present study was to determine the possible role of a cytokine network in a rat model of trinitrobenzene sulfonic acid-induced colitis and to examine its relation to intestinal permeability. After a rapid increase in the intestinal permeability of Evans blue in the colon, tumor necrosis factor-alpha increased transiently, and interleukin-1 and interleukin-6 followed thereafter. The majority of tumor necrosis factor-alpha- and interleukin-1-producing cells observed by immunofluorescent staining was revealed to be macrophages. Repeated injections of interleukin-1 receptor antagonist led to a modest decrease in myeloperoxidase activity and colon weight. These findings suggest that enhanced pro-inflammatory cytokine production from intestinal macrophages accompanied by increased intestinal permeability may contribute to intestinal and systemic features of trinitrobenzene sulfonic acid-induced colitis. Pharmacologic blockade of pro-inflammatory cytokines may help reduce intestinal inflammation.

Acute-Phase Proteins↗
PubMed1989

Identification and partial characterization of a T-cell-derived antigen-binding factor from mice infected with the intestinal helminth Trichinella spiralis.

Immunochemical and biological characterization was performed of an antigen-binding factor derived from culture supernatants of T cells from mice infected 4 days previously with the intestinal helminth Trichinella spiralis. Affinity chromatography with T. spiralis antigen resulted in the purification of a protein, provisionally designated Trichinella factor (Tric-F), that shared antigenic and other properties with a known T-cell-derived antigen-binding factor of different antigenic specificity, picryl chloride factor, which mediates an early 2-hour component of contact sensitivity. Tric-F lacked determinants of immunoglobulins and possessed determinants shared by other antigen-specific T cell factors, as determined by ELISA and antibody affinity chromatography. Biological activity of Tric-F was assayed in vivo and in vitro. Mice injected intravenously with Tric-F developed an antigen-specific early 2-hour ear swelling response following local challenge with T. spiralis antigen. These results corresponded to delayed-type hypersensitivity responses in the ears of T. spiralis-infected mice that comprised early 2-hour and late classical 24-hour responses. In vitro, Tric-F induced serotonin release by mast cells in the presence of T. spiralis antigen. Mast cells sensitized with Tric-F formed rosettes with antigen-coated sheep erythrocytes. It is suggested that Tric-F, an antigen-binding molecule that is T-cell-derived, mediates the early 2-hour component of delayed-type hypersensitivity and is involved in the initiation and regulation of T-cell-mediated intestinal inflammation during a T. spiralis infection in mice.

Animals↗
PubMed1995

Pathogenesis of traveler's diarrhea.

Diarrhea is the most common medical complication among persons venturing into tropical and semitropical regions of the developing world from industrialized regions. The illness is characteristically caused by one of a variety of bacterial agents, of which enterotoxigenic Escherichia coli is the most important. Intestinal electrolyte fluid movement explains the pathophysiology of most cases while in certain situations osmotic diarrhea or altered intestinal motility may lead to passage of unformed stools. In 1-2% of traveler, diarrhea lasts more than 1 month. Most of the patients will have diarrhea that is eventually self-limiting. The cause and mechanisms of diarrhea in these settings are largely unknown although a focal intestinal inflammation lesion may be found.

Bacterial Infections↗
PubMed2003

COX-1, COX-2 and the topical effect in NSAID-induced enteropathy.

The side effects of NSAIDs are equally evident in the stomach and the small bowel. The latter is increasingly seen as being clinically significant, contributing substantially to the iron-deficiency anaemia that is so common in patients with rheumatoid arthritis. Furthermore, NSAID-enteropathy may be associated with life-threatening events. The pathogenesis of NSAID-enteropathy is uncertain but inhibition of COX-1 is believed to be of pivotal importance. However there is increasing evidence that COX-2 inhibition and the topical effect may have a synergistic detrimental action. We examined the role of COX-1, COX-2 and the so called topical effect of acidic NSAIDs. We found that COX-1 or COX-2 inhibition and the topical effect alone do not damage the GI tract. Dual inhibition of COX-1 and COX-2 results in intestinal inflammation similar to that caused by Indomethacin. The topical effect may act synergistically in this damage. The conventional view that the mechanism of gastrointestinal damage is principally caused by COX-1 inhibition needs to be revised in view of recent studies using selective inhibitors of the COX enzymes and COX knockout animals.

Journal Article↗
PubMed2026

Shared CD4+ T cell receptor specificity groups in Crohn's disease and ulcerative colitis.

Inflammatory bowel disease (IBD), encompassing ulcerative colitis (UC) and Crohn's disease (CD), is marked by chronic intestinal inflammation and dysregulated immunity. Although UC and CD affect different areas of the gastrointestinal tract, both diseases share aberrant CD4+ memory T cell responses, with HLA-DRB1 as a major genetic risk factor. HLA-DRB1 encodes MHC class II molecules that influence the CD4+ T cell receptor (TCR) repertoire, yet how these genotypes shape TCR specificity in IBD remains unclear. Here, we genotyped HLA-DRB1 and profiled 3.13 million TCR&#x3b2; sequences from circulating memory CD4+ T cells in 33 IBD patients (20 UC, 13 CD) and 14 healthy controls. Using the GLIPH2 algorithm, we distilled 468,441 candidates based on CDR3 amino acid motifs into 440 high-confidence TCR specificity groups significantly enriched among individuals sharing HLA-DRB1 alleles. Notably, 5 specificity groups were IBD-enriched and were shared between UC and CD, suggesting common antigen targets in both diseases. We also observed increased frequencies of clonally expanded cytotoxic GZMB+PRF1+ memory CD4+ T cells and KIR+CD8+ T cells in a subset of risk-allele carriers with IBD. These findings elucidate distinct, HLA-linked TCR specificity groups in IBD and provide mechanistic insights that may advance antigen discovery and personalized medicine.

Humans↗