<<Disclaimer: Verify this information before applying it to your situation.>> In previous posts (The Thymus Gland - Part 1 and 2, Fri,15 Oct 2004) I have proposed that the thymus gland, impaired by malabsorption due to celiac disease, fails to sufficiently produce the regulatory T cells which help the immune system decide whether to tolerate or attack foreign proteins or antigens, thereby leading to or contributing to the numerous food allergies, intolerances, and autoimmune conditions so frequently associated with celiac disease. The following study demonstrates just how important the presence of properly selected regulatory T cells are in controlling inflammatory processes by showing the appropriate regulatory T cells can prevent colitis in mice. Certain types of colitis (inflammation of the large intestine) are associated with a high prevalence of celiac disease (see second abstract below.) An impaired thymus could be responsible for this prevalence. Recent studies have shown the prevalence of celiac disease in young children is nearly identical to the prevalence of celiac disease in adults, indicating that celiac disease has its origins during childhood. Thymus activity and production of T cells during childhood is especially critical for the proper development of the immune system. If the thymus is impaired by malabsorption due to celiac disease during childhood, the stage may be set for the development of future allergies, intolerences and autoimmune responses. The thymus, believed inactive after puberty, was only recently (1999) shown to remain active throughout life into adulthood. A diagnosis of celiac disease which so typically occurs after age 40 may well indicate the crucial repertoire of T cells produced by the thymus has already been severely compromised. It is imperative that the medical community screen for and diagnose celiac disease during childhood at the earliest possible stage. A close look at how the thymus is affected by celiac disease is highly warranted. ---------- Gut. 2005 Feb;54(2):207-14 Regulatory CD4+CD25+ cells reverse imbalances in the T cell pool of bone marrow transplanted TG{varepsilon}26 mice leading to the prevention of colitis. Veltkamp C, Sartor RB, Giese T, Autschbach F, Kaden I, Veltkamp R, Rost D, Kallinowski B, Stremmel W. Department of Gastroenterology, University of Heidelberg, INF 410, 69120 Heidelberg, Germany. [log in to unmask] BACKGROUND AND AIMS: Erroneous thymic selection of developing T lymphocytes may be responsible for the expansion of self reactive T cells or may contribute to the absence of regulatory T cells important in controlling peripheral inflammatory processes. Colitis in bone marrow (BM) transplanted Tgepsilon26 mice is induced by abnormally activated T cells developing in an aberrant thymic microenvironment. We investigated the protective role of regulatory CD4(+)CD25(+) T cells in this model. METHODS: BM from (C57BL/6xCBA/J) F1 mice was transplanted into specific pathogen free Tgepsilon26 mice (BM-->Tgepsilon26). Transplanted mice received no cells (control), sorted CD4(+)CD25(+), or CD4(+)CD25(-) cells from mesenteric lymph nodes (MLN) of normal mice. MLN cell subsets were analysed using membrane markers. Cytokine secretion of MLN cells was measured using intracellular cytokine staining and cytokine secretion in anti-CD3 stimulated cell cultures. Colitis was measured by histological scores. RESULTS: CD4(+)CD25(+) cells were reduced in the MLNs of BM-->Tgepsilon26 mice. Transfer of regulatory CD4(+)CD25(+) but not of CD4(+)CD25(-) cells reduced the number of MLN CD4(+) T cells in BM-->Tgepsilon26 recipients and increased the number of MLN CD8(+) cells, thereby normalising the CD4(+)/CD8 (+) ratio. CD4(+)CD25(+) but not CD4(+)CD25(-) cell transfer into BM-- >Tgepsilon26 mice reduced the number of tumour necrosis factor alpha(+) CD4 (+) cells and increased the secretion of transforming growth factor beta by MLN cells. Transfer of 3x10(5) CD4(+)CD25(+) cells after BM transplantation into Tgepsilon26 mice prevented colitis whereas CD4(+)CD25(-) cells had no protective effect. CONCLUSIONS: These results suggest that defective selection or induction of regulatory T cells in the abnormal thymus is responsible for the development of colitis in BM-->Tgepsilon26 mice. Transfer of CD4(+)CD25(+) cells can control intestinal inflammation in BM-- >Tgepsilon26 mice by normalising the number and function of the MLN T cell pool. PMID: 15647183 [PubMed - in process] --------- Scand J Gastroenterol. 2004 Sep;39(9):837-45 Clinical characteristics of collagenous and lymphocytic colitis. Koskela RM, Niemela SE, Karttunen TJ, Lehtola JK. Department of Internal Medicine, University of Oulu, OYS, PO Box 20, FIN- 90029 Oulu, Finland. [log in to unmask] BACKGROUND: Microscopic colitides (MC), collagenous colitis (CC) and lymphocytic colitis (LC) share clinical features, but their mutual relationship is unclear, and clinical comparative studies are rare. We aimed to examine the clinical features in CC and LC by focusing on concomitant diseases. METHODS: Patients with MC (30 with CC, 54 with LC) were identified in the pathology databases and by reviewing biopsies. Controls included 84 age- and sex-matched persons. The clinical data collected from patient records were prospectively completed by interviews. RESULTS: The female:male ratio was 2:1 in CC and 5.75:1 in LC. Mean age at diagnosis was 53 in CC and 55.4 years in LC. There were no differences in the pattern of symptoms. Concomitant autoimmune diseases were more common in CC (53.3%) than in LC (25.9%; P = 0.017). Celiac disease was common in both CC (20%) and LC (14.8%). Bronchial asthma was associated with LC (25.9%), but not with CC (6.7%; P = 0.042). Colon diverticulosis was rare in MC (16%) compared with the controls (39%; P = 0.001). Hypolactasia was common in MC (45%; 76% in CC, 54% in LC) compared to its prevalence in the Finnish general population (17%). CONCLUSIONS: CC and LC are largely similar clinically, but the differences in the occurrence of autoimmune conditions and bronchial asthma suggest that they differ in immunopathogenesis. MC is associated with reduced lactose tolerance and shows a negative association with diverticular disease, possibly related to the small intestinal pathology and abnormal stool consistency. PMID: 15513381 [PubMed - indexed for MEDLINE] * * * * Send administrative questions to [log in to unmask] *