The follicle-associated epithelium (FAE) of Peyer's patches (PPs) contains M cells that are important for reducing mucosal immune responses by transporting antigens into the underlying lymphoid tissue. We generated a monoclonal antibody (C6) that reacted with the FAE of calf ileal PPs, and analyzed the characteristics of C6 using immunohistochemistry and Western blotting. FAE of the ileal PP was stained with C6 during both late fetal developmental and postnatal stages. Neither the villous epithelial cell nor intestinal crypt basal cells were stained at any developmental stage. During the prenatal stages, FAE of the jejunal PP was C6-negative. However, a few C6-positive cells were distributed diffusely in some FAE of the jejunal PPs during the postnatal stages. The protein molecular weight of the antigen recognized by C6 was approximately 45 kDa. These data show that C6 is useful for identifying the FAE in ileal PPs and further suggest that differentiation of the FAE in these areas is independent of external antigens.
Animals ; Antibodies, Monoclonal/*immunology ; *Cattle ; Fetus ; Hybridomas ; Ileum/*ultrastructure ; Intestinal Mucosa/*immunology ; Peyer's Patches/*immunology/ultrastructure

The follicle-associated epithelium (FAE) of Peyer's patches (PPs) contains M cells that are important for reducing mucosal immune responses by transporting antigens into the underlying lymphoid tissue. We generated a monoclonal antibody (C6) that reacted with the FAE of calf ileal PPs, and analyzed the characteristics of C6 using immunohistochemistry and Western blotting. FAE of the ileal PP was stained with C6 during both late fetal developmental and postnatal stages. Neither the villous epithelial cell nor intestinal crypt basal cells were stained at any developmental stage. During the prenatal stages, FAE of the jejunal PP was C6-negative. However, a few C6-positive cells were distributed diffusely in some FAE of the jejunal PPs during the postnatal stages. The protein molecular weight of the antigen recognized by C6 was approximately 45 kDa. These data show that C6 is useful for identifying the FAE in ileal PPs and further suggest that differentiation of the FAE in these areas is independent of external antigens.
Animals ; Antibodies, Monoclonal/*immunology ; *Cattle ; Fetus ; Hybridomas ; Ileum/*ultrastructure ; Intestinal Mucosa/*immunology ; Peyer's Patches/*immunology/ultrastructure

Dendritic cells (DCs) are key modulators that shape the immune system. In mucosal tissues, DCs act as surveillance systems to sense infection and also function as professional antigen-presenting cells that stimulate the differentiation of naive T and B cells. On the basis of their molecular expression, DCs can be divided into several subsets with unique functions. In this review, we focus on intestinal DC subsets and their function in bridging the innate signaling and adaptive immune systems to maintain the homeostasis of the intestinal immune environment. We also review the current strategies for manipulating mucosal DCs for the development of efficient mucosal vaccines to protect against infectious diseases.
Animals ; Dendritic Cells/*immunology/metabolism ; Humans ; Immunity, Mucosal ; Intestinal Mucosa/cytology/*immunology ; T-Lymphocytes, Helper-Inducer/immunology

No abstract available.
Animals ; Apoptosis/*physiology ; Claudins/*metabolism ; Colitis/*physiopathology ; Intestinal Mucosa/*physiopathology ; Mannose-Binding Lectin/*immunology

The patients in gastrointestinal surgery are always accompanied with malnutrition. Parenteral nutrition is the main support method for patients with intestinal dysfunction. The normal intestinal mucosal immune system can protect against bacteria in the gut. Parenteral nutrition without enteral stimulation injures of the intestinal mucosal immunity and increases the risk of infection. It is very important to protect intestinal mucosal barrier by nutrition support therapy.
Digestive System Surgical Procedures ; Humans ; Immunity, Mucosal ; Intestinal Mucosa ; immunology ; surgery ; Nutritional Support ; Wound Healing

OBJECTIVETo investigate the effects of enteral nutrition on intestinal intraepithelial lymphocytes and the barrier of mucus in patients with stomal type enteric fistulas.

METHODSTen patients with stomal type enteric fistulas after long-term fasting were observed. They received enteral nutrition of 146 kJ.kg(-1).d(-1) non-protein calorie and 0.25 g.kg(-1).d(-1) nitrogen per day. Intestinal mucosa were taken by endoscope through stoma of fistula before, 5 and 10 days after enteral nutrition support. Hematoxylin-eosin stain and immunohistochemical stain were performed to count the cell counts of intestinal intraepithelial lymphocytes (iIELs) and mucin-2 (MUC2) positive cells, specific stain (Alcian Blue) was performed to test the thickness of mucus.

RESULTSFive days after enteral nutrition, MUC2 positive cells and the thickness of mucus were significantly higher than that before enteral nutrition support (P<0.05). Ten days after enteral nutrition, iIEL cell and CD8 counts were also significantly higher than that before enteral nutrition support (P<0.05), MUC2 positive cells and the thickness of mucus showed a significant increase (P<0.01).

CONCLUSIONEnteral nutrition is effective in protecting the gut mucosal and improving the immune function of the intestinal intraepithelial in patients with stomal type fistula.

Adolescent ; Adult ; Aged ; Cell Count ; Enteral Nutrition ; Female ; Humans ; Intestinal Fistula ; physiopathology ; therapy ; Intestinal Mucosa ; immunology ; physiopathology ; Intestine, Small ; Lymphocytes ; metabolism ; Male ; Middle Aged ; Mucus ; immunology ; Young Adult

To achieve immune homeostasis in such a harsh environment as the intestinal mucosa, both active and quiescent immunity operate simultaneously. Disruption of gut immune homeostasis leads to the development of intestinal immune diseases such as colitis and food allergies. Among various intestinal innate immune cells, mast cells (MCs) play critical roles in protective immunity against pathogenic microorganisms, especially at mucosal sites. This suggests the potential for a novel MC-targeting type of vaccine adjuvant. Dysregulated activation of MCs also results in inflammatory responses in mucosal compartments. The regulation of this yin and yang function of MCs remains to be elucidated. In this review, we focus on the roles of mucosal MCs in the regulation of intestinal allergic reaction, inflammation and their potential as a new target for the development of mucosal adjuvants.
Adjuvants, Immunologic/*therapeutic use ; Animals ; Humans ; Hypersensitivity/*immunology/prevention & control ; Inflammation/immunology/metabolism/prevention & control ; Intestinal Mucosa/cytology/*immunology ; Mast Cells/*immunology

Proliferative enteropathy was reproduced in IFN-gamma receptor knockout (IFN-gamma R-) mice by experimental infection with Lawsonia intracellularis (L. intracellularis). The cecum and the colon of the infected mice were evidently enlarged 2 weeks post infection. The presence of L. intracellularis was identified in the stool and the cecum of the mice after infection. However, high levels of IFN-gamma were detected in the sera of the infected mice 2 weeks PI. These data indicated that the IFN-gamma produced in the infected mice should have been utilized by it's receptor to elicit protective immune responses against L. intracellularis infections.
Animals ; DNA, Viral ; Desulfovibrionaceae Infections/*immunology/microbiology ; Interferon Type II/*immunology ; Intestinal Diseases/*immunology/microbiology ; Intestinal Mucosa/immunology ; Lawsonia Bacteria/*immunology/isolation&purification ; Mice ; Mice, Knockout ; Polymerase Chain Reaction ; Receptors, Interferon/physiology

Vaccination is one of the most successful applications of immunology and for a long time has depended on parenteral administration protocols. However, recent studies have pointed to the promise of mucosal vaccination because of its ease, economy and efficiency in inducing an immune response not only systemically, but also in the mucosal compartment where many pathogenic infections are initiated. However, successful mucosal vaccination requires the help of an adjuvant for the efficient delivery of vaccine material into the mucosa and the breaking of the tolerogenic environment, especially in oral mucosal immunization. Given that M cells are the main gateway to take up luminal antigens and initiate antigen-specific immune responses, understanding the role and characteristics of M cells is crucial for the development of successful mucosal vaccines. Especially, particular interest has been focused on the regulation of the tolerogenic mucosal microenvironment and the introduction of the luminal antigen into the lymphoid organ by exploiting the molecules of M cells. Here, we review the characteristics of M cells and the immune regulatory factors in mucosa that can be exploited for mucosal vaccine delivery and mucosal immune regulation.
Administration, Oral ; Animals ; Antigens, Bacterial/*immunology ; Antigens, Viral/*immunology ; Bacterial Vaccines/administration & dosage/*immunology ; Humans ; Immunity, Mucosal ; Intestinal Mucosa/cytology/*immunology ; Peyer's Patches/cytology/*immunology ; Viral Vaccines/administration & dosage/*immunology

Mucosal mast cell-derived chondroitin sulphates (sulphated proteoglycans) were assayed in gut washings and homogenate of FcRgamma-knockout (KO) and wild-type (WT) C57BL/6 mice challenged with Strongyloides venezuelensis in order to assess their possible role in secondary immunity against enteric nematodes. Groups of immune KO and WT mice were challenged by oral gavage with 300 infective larvae (L3). Establishment of infection was assessed by daily faecal analysis to determine the number of eggs per gram of faeces (EPG) and by adult worm recovery on days 5 and 13 post challenge. Mucosal mast cell (MMC) counts were done on days 5 and 13 post challenge while MMC-derived chondroitin sulphates in gut washings (days 1 and 5) and homogenate (day 8) were assayed by high performance liquid chromatography (HPLC). Results showed that patent infection occurred in challenged KO but not WT mice despite significantly higher mastocytosis in jejunal sections of KO than WT mice (p<0.001). Similarly but against prediction, significantly higher concentration of MMC-derived chondroitin sulphates was observed in gut homogenate of KO than WT mice (p<0.05). In contrast, significantly higher concentration of chondroitin sulphates was observed in gut washings of WT than KO mice (p<0.05). These results suggest that MMC in KO mice failed to release sufficient amount of sulphated proteoglycans into the gut lumen as did the WT mice, which may have been part of the hostile environment that prevented the establishment in and eventual expulsion of adult S. venezuelensis from the gut of WT mice following challenge.
Animals ; Cell Count/veterinary ; Chondroitin Sulfates/*immunology/metabolism ; Chymases ; Feces/parasitology ; Intestinal Diseases, Parasitic/immunology/*veterinary ; Intestinal Mucosa/cytology/immunology/parasitology ; Jejunum/cytology/immunology/parasitology ; Male ; Mast Cells/immunology/metabolism/*parasitology ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Parasite Egg Count/veterinary ; Receptors, IgG/*immunology ; Serine Endopeptidases/blood/immunology ; Specific Pathogen-Free Organisms ; Strongyloides/*immunology ; Strongyloidiasis/immunology/parasitology/*veterinary