Lymphocytes Peyer patch

Ruiz-Santana, S., Lopez, A., Torres, S., et al. (2001) Prevention of dexamethasone-induced lymphocytic apoptosis in the intestine and in Peyer patches by enteral nutrition. J Parenter Enteral Nutr 25, 338-345. 

NF-kB is also crucial for the proper functioning of the adaptive immune system not only by acting on the immune cells themselves but also by participating in the development and organization of the secondary lymphoid organs (lymph nodes, spleen, and Peyer s patches), in which both B and T lymphocytes undergo maturation and activation. NF-kB proteins have an important role in lymphocyte development and... 

J. Kraehenbuhl, and E. Pringault. Conversion by Peyer s patch lymphocytes of human enterocytes into M cells that transport bacteria., Science 1997, 277, 949-952... 

Salmonella all ages/travelers to tropics 6-48 h moderate volume, and usually without blood mucosal invasion via M cells or enterocytes - macrophages and lymphocytes in Peyer s patches and other lymphoid tissue - bloodstream... 

The gastrointestinal tract is considered the largest systemic lymphatic organ. It contains numerous lymphocytic groups which create appendix, sometimes referred to as abdominal tonsil, lymphatic nodes of gastrointestinal tract, solitary lymphatic follicles, and Peyer s patches at the base of intestinal villi. 

It is interesting that dendritic cells from Peyer s patches may produce IL 10, which can increase the percentage of Th2 lymphocytes releasing IL 4 and IL 10. 

Also epithelial cells—enterocy tes may be APC cells in humans—present antigens to T CD8 lymphocytes, which produce antigen nonspecific TCR (Mayer and Shlien, 1987). In rats, on the other hand, selective immunosuppression has been observed which was dependent on antigen-specific T lymphocytes (Bland and Warren, 1986) releasing TGI P, present in Peyer s patches as soon as within 24-48 h of the intake of small antigen doses (Lider et al., 1989). Occurrence of food tolerance may be due to some haptens, e.g., DNCB (2,4-dinitrochlorobenzene) administered to mice orally, according to Galliaerde et al. (1995). 

In addition, the mucosal surface of the intestine is essential for the assimilation of antigens. Proteases of the intestinal bacteria degrade the antigenic structure, an important step in the introduction of unresponsiveness to dietary antigens. Specialized antigen transport mechanisms take place in different lymphoid compartments mesenteric lymph nodes, Peyer s patches, isolated lymph follicles, isolated T lymphocytes in the epithelium and the lamina propria, as well as at the secretory sites (Heyman et al. 1982). The secretory IgA antibodies in the gut are part of the... 

Otani, H. and Hata, I. 1995. Inhibition of proliferative responses of mouse spleen lymphocytes and rabbit Peyer s patch cells by bovine milk caseins and their digests. J. Dairy Res. 62, 339-348. 

Figure 6.15 Schematic diagram of a portion of the epithelium covering above a lymphatic nodule in a Peyer s patch (mouse). Attenuated M cells (M) extend as membranelike cytoplasmic bridges between the absorptive columnar epithelial cells present on either side (C). Beneath the M cell lies a small nest of intraepithelial lymphocytes (L) together with a central macrophage (Mac). The M cell provides a thin membrane-like barrier between the lumen above and the lymphocytes in the intercellular space below. This M cell has taken up the macromolecules and particulate matter that reach it and macrophages (Mac) may ingest them. Modified from D.H. Cormack. Lymphatic tissue and the immune system. D.H.Cormack (ed.) (1987) Ham s Histology, J.B. Lippincott Company, Philadelphia, pp. 234-263...

Levine, Gibson and Megel19 studied the depletion of the lymphocyte population caused by tilorone hydrochloride given orally or subcutaneously to rats and mice in spleen, lymph nodes and Peyer s patches. Although the thymus itself was not affected, thymus-dependent areas were affected similarly to that caused by neonatal thymectomy, thymic aplasia, or antilymphocytic serum. The effects of tilorone were not dependent on the presence of adrenal, thymus or spleen, and the depleted tissues were rapidly repopulated. The previously sensitive areas were resistant to further doses of the same drug. 

Lymphoid organs, including spleert, tlymus, and Peyer s patches showed necrosis of T and B lymphocytes, the orrset of lesiorts depending on the dose (Ito et al. 2000). Again, recovery of severe injtrries to lymphoid organs was slow taking a period of 10 days (Ito et al. 2002). 

A few days before birth, lymphocytes and dendritic cells (DCs) are recruited to the lymph-node and Peyer s-patch anla-gen. Because T cells and B cells themselves express LT-ajp, recruitment of lymphocytes is amplified by a second positive-feedback loop and culminates in the formation of a mature lymph node or Peyer s patch consisting of segregated T-cell zones and B-cell follicles, HEVs and additional specialized mesenchymal cells. 

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