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Lymphoid Aggregates (lymphoid + aggregate)
Selected AbstractsThe proportion of CD40+ mucosal macrophages is increased in inflammatory bowel disease whereas CD40 ligand (CD154)+ T cells are relatively decreased, suggesting differential modulation of these costimulatory molecules in human gut lamina propriaINFLAMMATORY BOWEL DISEASES, Issue 11 2006Dr. Hege S. Carlsen MD Abstract Background: Signal transduction through binding of CD40 on antigen-presenting cells and CD40 ligand (CD154) on T cells appears to be crucial for mutual cellular activation. Antibodies aimed at blocking the CD40,CD154 costimulatory pathway dampen the severity of experimental colitis. To elucidate the microanatomical basis for signaling through this costimulatory pathway in human inflammatory bowel disease, we studied in situ the cellular distribution of these 2 molecules on lamina propria macrophages and T cells, respectively. Methods: Colonic specimens from 8 patients with ulcerative colitis and 8 with Crohn's disease, 8 small bowel specimens of Crohn's disease, and histologically normal control samples (6 from colon and 6 from small bowel) were included. Multicolor immunofluorescence in situ staining was performed to determine the percentage of subepithelial macrophages expressing CD40 and that of lamina propria T cells expressing CD154 while avoiding cells in lymphoid aggregates. Results: The proportion of subepithelial CD40highCD68+ macrophages was significantly increased in normal colon compared with normal small bowel and showed further elevation in both colon and small bowel afflicted with inflammatory bowel disease. In addition, on a per-CD68+ -cell basis, CD40 expression was significantly increased in severely inflamed compared with moderately inflamed colonic specimens. Conversely, the proportion of CD154+ T cells was similar in colon and small bowel, and interestingly, it was significantly reduced in colonic inflammatory bowel disease. Conclusions: Our findings suggested that modulation of CD40 expression by subepithelial macrophages and CD154 by lamina propria T cells is inversely modulated in the human gut. [source] Nodular gastritis in adults: Clinical features, endoscopic appearance, histopathological features, and response to therapyJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 6 2008Manisha Dwivedi Abstract Background and Aims:, The present study aims to determine the prevalence of nodular gastritis (NG) and ascertain its clinical presentation and histopathological features in adults. It also assesses its association with Helicobacter pylori and the normalization of endoscopic features, symptoms, and histology after anti H. pylori therapy. Methods:, A total of 7140 patients undergoing upper gastrointestinal endoscopy were studied. Patients showing nodularity of the gastric mucosa at endoscopy and an age- and sex-matched control group with normal gastric mucosa underwent biopsies from the gastric antrum and fundus. The biopsies were assessed for the presence of mucosal inflammation, activity, eosinophils, atrophy, lymphoid follicles, H. pylori, and the presence of intestinal metaplasia. Patients with NG were given triple therapy. Endoscopy and biopsy was repeated after 4 weeks of stopping therapy. The symptoms of the patients and histology were assessed pre- and post-therapy. Results:, Thirty-two patients with an age range of 20,65 years presenting with NG and 40 age- and sex-matched controls were included in the study. Presenting symptoms were epigastric pain (56%), nausea (75%), vomiting (50%) and abdominal bloating (62.5%). All these symptoms regressed significantly after 2 week of triple therapy against H. pylori. A marked improvement in histopathological features was seen post-therapy where the presence of lymphoid aggregates, eosinophils in the mucosa, atrophy, and intestinal metaplasia improved significantly (P < 0.05) after therapy, as compared to the control group of patients. Conclusion:, The symptoms of NG and endoscopic features regress significantly after H. pylori therapy with a proton pump inhibitor and two antibiotics and should routinely be given to treat this form of gastritis. This may prevent progression to further complications. [source] Developmental morphology of the neonatal alligator (Alligator mississippiensis) ovaryJOURNAL OF MORPHOLOGY, Issue 3 2008Brandon C. Moore Abstract American alligator (Alligator mississippiensis) ovary development is incomplete at hatching. During the months following hatching, the cortical processes of oogenesis started in ovo continues and folliculogenesis is initiated. Additionally, the medullary region of the gonad undergoes dramatic restructuring. We describe alligator ovarian histology at hatching, 1 week, 1 month, and 3 months of age in order to characterize the timing of morphological development and compare these findings to chicken ovary development. At hatching, the ovarian cortex presents a germinal epithelium containing oogonia and a few primary oocytes irregularly scattered between somatic epithelial cells. The hatchling medulla shows fragmentation indicative of the formation of lacunae. By 1 week of age, oocytes form growing nests and show increased interactions with somatic cells, indicative of the initiation of folliculogenesis. Medullary lacunae increase in diameter and contain secretory material in their lumen. At 1 month, nest sizes and lacunar diameters continue to enlarge. Pachytene oocytes surrounded by somatic cells are more frequent. Trabeculae composed of dense irregular connective tissue divide cortical nests. Three months after hatching oocytes in meiotic stages of prophase I up to diplotene are present. The ovary displays many enlarged follicles with oocytes in diplotene arrest, thecal layers, lampbrush chromosomes, and complete layers of follicular cells. The medulla is an elaborated complex of vascularized lacunae underlying the cortex and often containing discrete lymphoid aggregates. While the general morphology of the alligator ovary is similar to that of the chicken ovary, the progression of oogenesis and folliculogenesis around hatching is notably slower in alligators. Diplotene oocytes are observed at hatching in chickens, but not until 3 months in alligators. Folliculogenesis is completed at 3 weeks in chickens whereas it is still progressing at 3 months in alligators. J. Morphol., 2008. © 2007 Wiley-Liss, Inc. [source] Follicular dendritic cells confirm lymphoid organization in the minor salivary glands of primary Sjögren's syndromeJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 9 2008Malin V. Jonsson Background:, Sjögren's syndrome (SS) is an autoimmune chronic inflammatory disorder affecting the salivary and lacrimal glands. The aim of this study was to explore immunophenotypic features of chronic inflammatory reactions in the minor salivary glands in patients with primary SS (pSS). Methods:, Formalin-fixed, paraffin-embedded labial minor salivary gland tissue sections from randomly selected patients with pSS (n = 60) were investigated for the expression of CD21, CD23, CD35 and IgD by immunohistochemistry. Results:, Based on the distribution and staining pattern of CD21, CD23, CD35 and IgD in lymphoid aggregates, several stages of chronic inflammatory reactions were observed. In 12/60 (20%) patients, lymphoid infiltrates with germinal centre (GC)-like features such as extensive networks of CD21-, CD23- and CD35-positive cells were observed in the minor salivary gland tissue. Smaller networks and,/or focal infiltrates with scattered CD21+, CD23+ and CD35+ cells were observed in the remaining 48/60 (80,%) cases. When dividing patients according to the presence (GC+) or the absence (GC,) of GC in the minor salivary glands, the mean focus score was significantly higher in the GC+ patients (P < 0.05). Double staining of the minor salivary glands revealed focal infiltrates with follicular dentritic cell networks and B cells resembling normal GCs in tonsillar tissue. Conclusion:, A particular cellular profile was demonstrated in a sub-group of patients with pSS and could be linked to serological aberrations. These findings warrant further prospective studies. [source] Quilty Effect Has the Features of Lymphoid Neogenesis and Shares CXCL13,CXCR5 Pathway With Recurrent Acute Cardiac RejectionsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 1 2007E. Di Carlo Quilty effect (QE) is a frequent, yet enigmatic feature of cardiac allograft, since it is apparently devoid of clinical significance, though its association with acute (A) rejection (R) is strongly suspected. It was observed in 126/379 biopsies from 22 patients during the first posttransplant year. Most grade (G)2R biopsies displayed a concomitant QE. The following features typical of QE were identified: (a) focal angiogenesis and lymphangiogenesis associated with bFGF, VEGF-C and VEGF-A expression, (b) marked infiltrate of CD4+T and CD20+B followed by CD8+T lymphocytes arranged around PNAd+HEV-like vessels. Most QE appear as distinct B,T-cell-specific areas with lymphoid follicles sometimes endowed with germinal center-like structures containing VCAM-1+CD21+FDC and CD68+macrophages, which frequently expressed CXCL13. These cells were also found in mantle-like zones, where small lymphocytes expressed CXCR5, otherwise in the whole area of not clustered lymphoid aggregates. CXCL13 was also expressed, in association with CD20+B lymphocyte recruitment, in G2R biopsies obtained from patients with recurrent AR. QE has features of a tertiary lymphoid tissue suggesting an attempt, by the heart allograft, to mount a local response to a persistent alloantigen stimulation resulting in aberrant CXCL13 production, as also occurs in recurrent AR. CXCL13-CXCR5 emerge as a common molecular pathway for QE and recurrent episodes of AR. [source] Immmunohistochemical Study of the Blood and Lymphatic Vasculature and the Innervation of Mouse Gut and Gut-Associated Lymphoid TissueANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2007B. Ma Summary The blood and lymphatic vascular system of the gut plays an important role in tissue fluid homeostasis, nutrient absorption and immune surveillance. To obtain a better understanding of the anatomic basis of these functions, the blood and lymphatic vasculature of the lower segment of mouse gut and several constituents of gut-associated lymphoid tissue (GALT) including Peyer's patch, specialized lymphoid nodules in the caecum, small lymphoid aggregates and lymphoid nodules in the colon were studied by using confocal microscopy. Additionally, the innervation and nerve/immune cell interactions in the gut and Peyer's patch were investigated by using cell surface marker PGP9.5 and Glial fibrillary acidic protein (GFAP). In the gut and Peyer's patch, the nerves have contact with B cell, T cell and B220CD3 double-positive cells. Dendritic cells, the most important antigen-presenting cells, were closely apposed to some nerves. Some dendritic cells formed membrane,membrane contact with nerve terminals and neuron cell body. Many fine nerve fibres, which are indirectly detected by GFAP, have contact with dendritic cells and other immune cells in the Peyer's patch. Furthermore, the expression of Muscarinic Acetylcholine receptor (subtype M2) was characterized on dendritic cells and other cell population. These findings are expected to provide a route to understand the anatomic basis of neuron-immune regulation/cross-talk and probably neuroinvasion of prion pathogens in the gut and GALT. [source] Inflammation and angiogenesis in osteoarthritisARTHRITIS & RHEUMATISM, Issue 8 2003L. Haywood Objective To quantify the relationship between inflammation and angiogenesis in synovial tissue from patients with osteoarthritis (OA). Methods Hematoxylin and eosin staining and histologic grading for inflammation were performed for 104 patients who met the American College of Rheumatology criteria for OA and had undergone total joint replacement or arthroscopy. A purposive sample of synovial specimens obtained from 70 patients was used for further analysis. Vascular endothelium, endothelial cell (EC) proliferating nuclei, macrophages, and vascular endothelial growth factor (VEGF) were detected by immunohistochemical analysis. Angiogenesis (EC proliferation, EC fractional area), macrophage fractional area, and VEGF immunoreactivity were measured using computer-assisted image analysis. Double immunofluorescence histochemical analysis was used to determine the cellular localization of VEGF. Radiographic scores for joint space narrowing and osteophyte formation in the knee were also assessed. Results Synovial tissue samples from 32 (31%) of 104 patients with OA showed severe inflammation; thickened intimal lining and associated lymphoid aggregates were often observed. The EC fractional area, EC proliferation, and VEGF immunoreactivity all increased with increasing histologic inflammation grade and increasing macrophage fractional area. In the synovial intimal lining, VEGF immunoreactivity was localized to macrophages and increased with increasing EC fractional area and angiogenesis. No inflammation or angiogenic indices were significantly correlated with radiographic scores. Conclusion Inflammation and angiogenesis in the synovium are associated with OA. The angiogenic growth factor VEGF generated by the inflamed synovium may promote angiogenesis, thereby contributing to inflammation in OA. [source] | |||||||||||||