The small intestine is essential for digestion, nutrient absorption, immune regulation, and microbial balance. Its epithelial lining, containing specialized cells like Paneth cells and tuft cells, is crucial for maintaining intestinal homeostasis. Paneth cells produce antimicrobial peptides and growth factors that support microbial regulation and intestinal stem cells, while tuft cells act as chemosensors, detecting environmental changes and modulating immune responses. Along with immune cells such as intraepithelial lymphocytes, innate lymphoid cells, T cells, and macrophages, they form a strong defense system that protects the epithelial barrier. Disruptions in this balance contribute to chronic inflammation, microbial dysbiosis, and compromised barrier function-key features of inflammatory bowel disease, celiac disease, and metabolic syndromes. Furthermore, dysfunctions in the small intestine and immune cells are linked to systemic diseases like obesity, diabetes, and autoimmune disorders. Recent research highlights promising therapeutic strategies, including modulation of epithelial and immune cell functions, probiotics, and gene editing to restore gut health and address systemic effects. This review emphasizes the pivotal roles of small intestinal epithelia and immune cells in maintaining intestinal homeostasis, their involvement in disease development, and emerging treatments for intestinal and systemic disorders.
Humans ; Intestinal Mucosa/cytology* ; Intestine, Small/cytology* ; Animals ; Inflammatory Bowel Diseases/immunology* ; Celiac Disease/immunology* ; Paneth Cells/immunology*

Establishing a suitable animal model is important for studying the mechanism of inflammatory bowel disease (IBD) and exploring new therapeutic approaches. Although a large number of IBD single gene knockout animal models have been established, single knockout of certain genes associated with human IBD susceptibility does not manifest symptoms of IBD or manifest extremely milder symptoms, while composite animal models based on other modeling factors can better simulate the clinical features of IBD. This article mainly introduces three novel composite animal models and elaborates the possible pathogenesis of each composite model:animal models established by gene double knockout have more obvious and earlier symptoms than single-knockout models; single gene knockout model with Helicobacter infection can help to study the role of microbial infections in the pathogenesis of IBD; on the basis of gene knockout, specific deletion of certain immune cells can be used to study the role of the immune cells in the development of IBD. Among the above composite animal models, double knockout mice may be important animal models for IBD study.
Animals ; Disease Models, Animal ; Gene Knockout Techniques ; Humans ; Inflammatory Bowel Diseases ; genetics ; immunology ; Mice, Knockout ; Research

Inflammatory bowel disease (IBD) is a chronic progressive idiopathic inflammatory disorder that involves the digestive tract from the mouth to the anus. Over the past decades, many therapeutic strategies have been developed to manage IBD, but therapeutic strategies based only on relief of clinical symptoms have not changed the natural history of this disease entity. This underlines the importance of understanding the natural history of IBD itself. When we look at the natural history of Crohn's disease (CD), it first begins with inflammation of the intestinal mucosa and this inflammatory reaction proceeds to stenosing or penetrating reaction if not adequately controlled. However, it takes a considerable amount of time before mucosal inflammation proceeds to stenosis of the intestinal lumen or penetration into the adjacent bowel. Therefore, it can be expected that if proper care is given during that period, progression of CD to such a complicated disease could be prevented. Even though the concept of mucosal healing was introduced in the early 1990s, no correlation could be observed between healing of mucosal lesions and relief of clinical symptoms. However, the introduction of biologic agents targeting tumor necrosis factor has changed the way to treat IBD that is refractory to standard medications and has allowed us to aim for a new therapeutic goal, 'deep remission'. Further advances in biologic agents have provided highly effective treatments for IBD, making deep remission a realistic goal. Whether IBD patients may benefit by experiencing a 'deep' remission beyond the control of clinical symptoms need to be evaluated in further investigation. Nevertheless, it can be anticipated that attaining deep remission might ultimately have an impact on important outcomes such as the need for surgery and the quality of life.
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use ; Antibodies, Monoclonal/therapeutic use ; Colitis, Ulcerative/drug therapy/metabolism/pathology ; Crohn Disease/drug therapy/metabolism/pathology ; Humans ; Inflammatory Bowel Diseases/drug therapy/metabolism/*pathology ; Intestinal Mucosa/metabolism/pathology ; Mesalamine/therapeutic use ; Tumor Necrosis Factor-alpha/immunology/metabolism

Inflammatory bowel disease (IBD) is a long-standing disease that often requires long-term use of immunosuppressive agents including immunomodulators (such as azathioprine, 6-mercaptopurine and methotrexate) and tumor necrosis factor-alpha inhibitors (such as infliximab and adalimumab). Introduction of immunosuppressive therapies, however, involves the risk of host susceptibility to opportunistic infections in this patient population. Therefore, adequate immunization for vaccine-preventable infectious diseases is currently recommended for all patients with IBD and is emerging as an important target for quality improvements in IBD care. However, ongoing issues regarding underuse of immunization, safety and efficacy of vaccines in patients with IBD remain. For quality improvements in IBD care, all physicians should follow the recent immunization guidelines proposed by professional IBD societies. Additionally, there are ongoing needs for intensive educational programs regarding a role of immunization in long-term care of IBD and up-to-date immunization guidelines. Immunization status should be checked at the time of diagnosis of IBD and timely vaccination before initiation of immunosuppressive therapies can be a practical solution for maximizing the efficacy of vaccination at this point. Inactivated vaccines can be used safely irrespective of immunization status of patients, while attenuated vaccines are contraindicated in patients on immunosuppressive therapies. This article reviews an ideal strategy for vaccinating patients with IBD based on the currently recommended immunization guidelines.
Antibodies, Monoclonal/therapeutic use ; Humans ; Immunosuppressive Agents/therapeutic use ; Inflammatory Bowel Diseases/diagnosis/drug therapy/*immunology ; Influenza Vaccines/immunology ; Influenza, Human/prevention & control ; Pneumonia/prevention & control ; *Vaccination ; Vaccines, Synthetic/immunology

BACKGROUND/AIMS: Inflammatory bowel disease (IBD) is a chronic disease of the gastrointestinal tract, whose etiologies are still unknown. This study was performed to evaluate the humoral immune response in terms of B cell functions in selected IBD patients. METHODS: Eighteen pediatric patients with IBD, including 12 cases of ulcerative colitis (UC) and six with Crohn disease (CD), were enrolled in this study. The pneumococcal vaccine was injected in all patients, and the IgG antibody level to the polysaccharide antigen was measured before and 4 weeks after injection. The B cell switch-recombination process was evaluated. RESULTS: Five patients with IBD (three CD and two UC) had defects in B cell switching, which was significantly higher than in controls (p=0.05). Ten patients had a specific antibody deficiency and exhibited a higher frequency of bacterial infection than the healthy group. The mean increased level of IgG after vaccination was lower in IBD patients (82.9+/-32.5 microg/mL vs 219.8+/-59.0 microg/mL; p=0.001). Among the patients who had an insufficient response, no significant difference in the number of switched memory B-cell was observed. CONCLUSIONS: A defect in B lymphocyte switching was observed in pediatric IBD patients, and especially in those patients with CD. Owing to an increased risk of bacterial infections in those patients with antibody production defects, pneumococcal vaccination could be recommended. However, not all patients can benefit from the vaccination, and several may require other prophylactic methods.
Adolescent ; Antibody Formation/*drug effects ; B-Lymphocytes/metabolism ; Child ; Child, Preschool ; Colitis, Ulcerative/complications/*immunology ; Crohn Disease/complications/*immunology ; Female ; Humans ; Immunoglobulin G/metabolism ; Inflammatory Bowel Diseases/complications/*immunology ; Male ; Pneumococcal Vaccines/*pharmacology ; Polysaccharides/*pharmacology ; Treatment Outcome

The incidence and prevalence of inflammatory bowel diseases (IBDs) including ulcerative colitis and Crohn disease are rapidly increasing in Western countries and in developed Asian countries. Although biologic agents targeting the immune system have been effective in patients with IBD, cessation of treatment leads to relapse in the majority of patients, suggesting that intrinsic immune dysregulation is an effect, not a cause, of IBD. Dramatic changes in the environment, resulting in the dysregulated composition of intestinal microbiota or dysbiosis, may be associated with the fundamental causes of IBD. Japan now has upgraded water supply and sewerage systems, as well as dietary habits and antibiotic overuse that are similar to such features found in developed Western countries. The purpose of this review article was to describe the association of diet, particularly Japanese food and microbiota, with IBD.
Animals ; *Asian Continental Ancestry Group ; Diet/*ethnology ; Evidence-Based Medicine ; Food Habits/ethnology ; Humans ; Incidence ; Inflammatory Bowel Diseases/diagnosis/diet therapy/*ethnology/immunology/*microbiology ; Intestines/immunology/*microbiology ; Japan/epidemiology ; *Microbiota ; Prevalence ; Probiotics/therapeutic use ; Prognosis ; Risk Factors

BACKGROUND/AIMS: Vaccinations are generally recommended in patients with inflammatory bowel disease (IBD). However, several studies showed low rates of vaccinations in IBD patients. Furthermore, vaccination rate among IBD patients in Korea has never been investigated. We investigated the vaccination rate among IBD patients in Korea and evaluated some factors that might affect the vaccination rate. METHODS: From November 2011 to February 2012, a total of 192 patients with IBD who visited Samsung Medical Center (Seoul, Korea) answered the IRB-approved questionnaire. The questionnaire included their sex, age, residence, past medical history, type of IBD, duration of illness, medications, history of vaccination about measles-mumps-rubella (MMR), varicella, tetanus-diphtheria (Td), influenza, hepatitis A and B, pneumococcus and human papilloma virus (HPV). RESULTS: One hundred twenty one (63.0%) male and 71 (37.0%) female answered the questionnaire. The mean age of the enrolled patients was 39.7 (18-76) years. Eighty four patients (43.8%) had ulcerative colitis and 108 patients (56.3%) had Crohn's disease (CD). The percentage of the patients who had got vaccination was 42.2% for MMR, 34.9% for varicella, 15.6% for Td, 37.5% for influenza, 15.6% for hepatitis A, 52.6% for hepatitis B, 6.3% for pneumococcus and 11.3% for HPV respectively. Not knowing the necessity or the existence were the common reasons for non-vaccination. Age less than 40 years, CD patients and duration of illness less than 10 years were associated with a higher vaccination rate (p=0.002, 0.015 and 0.020, respectively). CONCLUSIONS: Immunization rates for recommended vaccinations were very low in patients with IBD. Efforts to improve vaccination rate are needed.
Adolescent ; Adult ; Aged ; Chickenpox/prevention & control ; Colitis, Ulcerative/pathology ; Crohn Disease/pathology ; Diphtheria/prevention & control ; Female ; Hepatitis A/prevention & control ; Hepatitis B/prevention & control ; Humans ; Inflammatory Bowel Diseases/*immunology/pathology ; Male ; Measles/prevention & control ; Middle Aged ; Mumps/prevention & control ; Papillomavirus Infections/prevention & control ; Pneumococcal Infections/prevention & control ; Questionnaires ; Republic of Korea ; Rubella/prevention & control ; Tetanus/prevention & control ; *Vaccination ; Young Adult

Understanding of the pathophysiology of inflammatory bowel disease (IBD) is constantly evolving and, recently, a number of biologic agents have been developed. They selectively target specific molecule or pathways and correct the imbalance of the gut immune system. Among them, antibody to tumor necrosis factor (anti-TNF-alpha) is the first developed drugs, and it dramatically improved the IBD management. However, more than one-third of the patients do not respond to the drugs due to antibody formation. To increase treatment efficacy, enormous effort to develop novel anti-cytokines which can be an alternative to anti-TNF-alpha has been made. They are anti CD4+ T cell cytokine including interleukin (IL)-12/23 and IL-17 blockers, selective anti-adhesion molecule known as natalizumab, vedolizumab and alicaforsen, T-cell proliferation inhibitor, anti-inflammatory cytokine, immune stimulator, growth factor, and mitogen-activated protein kinase inhibitor. The efficacy and safety of each drugs are under investigation. Some drugs reported very promising data, however, others showed disappointing and different results. In addition, most of the trials were done in a very small number of patients, and there is no trial comparing to anti-TNF-alpha. The present paper reviews the action mechanism, short or long term efficacy and safety of variable drugs other than anti-TNF-alpha in IBD.
Antibodies, Monoclonal/therapeutic use ; Cell Migration Inhibition ; Colony-Stimulating Factors/therapeutic use ; Cytokines/antagonists & inhibitors ; Gene Therapy ; Humans ; Immunosuppressive Agents/therapeutic use ; Inflammatory Bowel Diseases/drug therapy/*therapy ; Intercellular Signaling Peptides and Proteins/therapeutic use ; Mitogen-Activated Protein Kinases/antagonists & inhibitors ; Stem Cell Transplantation ; Tumor Necrosis Factor-alpha/*antagonists & inhibitors/immunology

OBJECTIVETo reveal the efficacy on early postoperative inflammatory small bowel obstruction (EPISBO) treated with electroacupuncture and acupuncture separately and make the comparison of the efficacy difference.

METHODSThrough retrospective analysis, 459 cases of EPISBO were divided into an electroacupuncture group (355 cases) and an acupuncture group (104 cases). Based on routine treatment, Zusanli (ST 36), Shangjuxu (ST 37), Taichong (LR 3), Gongsun (SP 4) and Xuanzhong (GB 39) were selected in either group, but stimulated with electroacupuncture and acupuncture separately, once per day, for 30 min each time.

RESULTSAll of 459 cases were cured. The average days of curative achievement in electroacupuncture group were less apparently than those in acupuncture group (13.5 +/- 7.5 vs. 20.8 +/- 6.5, P < 0.05). The days of curative achievement in either group were less significantly than those treated with parenteral nutrition and medication recorded in literatures (32.0 +/- 7.0, both P < 0.05).

CONCLUSIONEither electroacupuncture or acupuncture achieves a significant efficacy on EPISBO, but the efficacy of electroacupuncture is better than that of acupuncture.

Acupuncture Therapy ; Adult ; Aged ; Electroacupuncture ; Female ; Humans ; Inflammatory Bowel Diseases ; therapy ; Intestinal Obstruction ; immunology ; therapy ; Intestine, Small ; immunology ; surgery ; Male ; Middle Aged ; Postoperative Complications ; immunology ; therapy ; Retrospective Studies ; Young Adult

TNF-alpha is a major cytokine involved in inflammatory bowel disease (IBD). In this study, water extract of Grifola frondosa (GFW) was evaluated for its protective effects against colon inflammation through the modulation of TNF-alpha action. In coculture of HT-29 human colon cancer cells with U937 human monocytic cells, TNF-alpha-induced monocyte adhesion to HT-29 cells was significantly suppressed by GFW (10, 50, 100 microg/ml). The reduced adhesion by GFW correlated with the suppressed expression of MCP-1 and IL-8, the major IBD-associated chemokines. In addition, treatment with GFW significantly suppressed TNF-alpha-induced reactive oxygen species production and NF-kappaB transcriptional activity in HT-29 cells. In differentiated U937 monocytic cells, LPS-induced TNF-alpha production, which is known to be mediated through NF-kappaB activation, was significantly suppressed by GFW. In an in vivo rat model of IBD, oral administration of GFW for 5 days (1 g/kg per day) significantly inhibited the trinitrobenzene sulfonic acid (TNBS)-induced weight loss, colon ulceration, myeloperoxidase activity, and TNF-alpha expression in the colon tissue. Moreover, the effect of GFW was similar to that of intra-peritoneal injection of 5-aminosalicylic acid (5-ASA), an active metabolite of sulfasalazine, commonly used drug for the treatment of IBD. The results suggest that GFW ameliorates colon inflammation by suppressing production of TNF-alpha as well as its signaling through NF-kappaB leading to the expression of inflammatory chemokines, MCP-1 and IL-8. Taken together, the results strongly suggest GFW is a valuable medicinal food for IBD treatment, and thus may be used as an alternative medicine for IBD.
Animals ; Cell Adhesion/drug effects/immunology ; Cell Extracts/administration & dosage/*pharmacology ; Chemokine CCL2/biosynthesis/genetics ; Coculture Techniques ; Colon/drug effects/*metabolism/pathology ; Grifola ; HT29 Cells ; Humans ; Inflammatory Bowel Diseases/chemically induced/*drug therapy/pathology/physiopathology ; Interleukin-8/biosynthesis/genetics ; Intestinal Mucosa/*drug effects/metabolism/pathology ; Monocytes/*drug effects/metabolism/pathology ; NF-kappa B/genetics/metabolism ; Peroxidase/metabolism ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species/metabolism ; Stomach Ulcer ; Transcription, Genetic/drug effects ; Trinitrobenzenesulfonic Acid/administration & dosage ; Tumor Necrosis Factor-alpha/*biosynthesis/genetics ; U937 Cells ; Weight Loss