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Background: Enteric neuropathy is described in most patients with gastrointestinal dysmotility and may be found together with reduced intraepidermal nerve fiber density (IENFD). The aim of this pilot study was to assess whether three-dimensional (3d) imaging of skin biopsies could be used to examine various tissue components in patients with gastrointestinal dysmotility. Material and methods: Four dysmotility patients of different etiology and two healthy volunteers were included. From each subject, two 3-mm punch skin biopsies were stained with antibodies against protein gene product 9.5 or evaluated as a whole with two X-ray phase-contrast computed tomography (CT) setups, a laboratory µCT setup and a dedicated synchrotron radiation nanoCT end-station. Results: Two patients had reduced IENFD, and two normal IENFD, compared with controls. µCT and X-ray phase-contrast holographic nanotomography scanned whole tissue specimens, with optional high-resolution scans revealing delicate structures, without differentiation of various fibers and cells. Irregular architecture of dermal fibers was observed in the patient with Ehlers-Danlos syndrome and the patient with idiopathic dysmotility showed an abundance of mesenchymal ground substance. Conclusions: 3d phase-contrast tomographic imaging may be useful to illustrate traits of connective tissue dysfunction in various organs and to demonstrate whether disorganized dermal fibers could explain organ dysfunction. (Less)

Telocytes (TCs) are recently described interstitial cells, present in almost all human organs. Among many other functions, TCs regulate gastrointestinal motility together with the interstitial cells of Cajal (ICCs). TCs and ICCs have close localization in the human myenteric plexus; however, the exact spatial relationship cannot be clearly examined by previously applied double immunofluorescence/confocal microscopy. Data on TCs and submucosal ganglia and their relationship to intestinal nerves are scarce. The aim of the study was to analyse the spatial relationship among these components in the normal human ileum and colon with double CD34/CD117 and CD34/S100 immunohistochemistry and high‐resolution light microscopy. TCs were found to almost completely encompass both myenteric and submucosal ganglia in ileum and colon. An incomplete monolayer of ICCs was localized between the TCs and the longitudinal muscle cells in ileum, whereas only scattered ICCs were present on both surfaces of the colonic myenteric ganglia. TC‐telopodes were observed within colonic myenteric ganglia. TCs, but no ICCs, were present within and around the interganglionic nerve fascicles, submucosal nerves and mesenterial nerves, but were only observed along small nerves intramuscularly. These anatomic differences probably reflect the various roles of TCs and ICCs in the bowel function.

Neuropathy should be considered as a possible etiological factor in patients with severe gastrointestinal symptoms, without signs of disease on routine investigations. Examinations of the autonomic and peripheral nervous systems may be helpful to select the patients who should be investigated with full‐thickness intestinal biopsy, and to give appropriate care.

A full-thickness biopsy of the bowel wall is required to evaluate the enteric nervous system. A patient with aggravating gastrointestinal symptoms underwent a laparoscopic full-thickness biopsy of the ileum and, 1 year later, an endoscopic full-thickness biopsy of the sigmoid colon. Both samples showed enteric neuropathy characterized by vacuolated and enlarged neurons. The length of the myenteric plexus was greater in the endoscopic (23 mm) compared to the laparoscopic (11 mm) biopsy, with fewer tissue artefacts in the laparoscopic approach. Clinical deterioration was paralleled by enteric neuropathy with an increase in the percentage of vacuolated and enlarged enteric neurons from 24 to 35%.

The cover image is based on the Case Report Autonomic and peripheral neuropathy with reduced intraepidermal nerve fiber density can be observed in patients with gastrointestinal dysmotility by Bodil Ohlsson, Béla Veress, LARS B DAHLIN et al., https://doi.org/10.1002/ccr3.2575. [Image: see text]

Objectives: Light microscopical analysis in two dimensions, combined with immunohistochemistry, is presently the gold standard to describe the enteric nervous system (ENS). Our aim was to assess the usefulness of three-dimensional (3D) imaging by X-ray phase-contrast tomography in evaluating the ENS of the human bowel. Material and methods: Myenteric ganglia were identified in full-thickness biopsies of the ileum and colon by hematoxylin & eosin staining. A1-mm biopsy punch was taken from the paraffin blocks and placed into a Kapton® tube for subsequent tomographic investigation. The samples were scanned, without further preparation, using phase-contrast tomography at two different scales: overview scans (performed with laboratory setups), which allowed localization of the nervous tissue (∼1µm effective voxel size); and high-resolution scans (performed with a synchrotron endstation), which imaged localized regions of 320x320x320 µm3 (176 nm effective voxel size). Results: The contrast allowed us to follow the shape and the size changes of the ganglia, as well as to study their cellular components together with the cells and cellular projections of the periganglional space. Furthermore, it was possible to show the 3D network of the myenteric plexus and to quantify its volume within the samples. Conclusions: Phase-contrast X-ray tomography can be applied for volume analyses of the human ENS and to study tissue components in unstained paraffin-embedded tissue biopsies. This technique could potentially be used to study disease mechanisms, and to compare healthy and diseased tissues in clinical research.

Gastrointestinal complaints without obvious organic causes confirmed by clinical laboratory analyses, endoscopy or radiology are often referred to functional entities. Irritable bowel syndrome (IBS) is the most common functional disorder in the gut. Careful examination of these patients may reveal other diagnoses of defined etiologies, e.g., enteric neuropathy, microscopic colitis, and primary Sjögre’s syndrome. The present case describes a young patient with incapacitating gastrointestinal symptoms presumed to be IBS, who underwent endoscopic full-thickness biopsy in sigmoid colon. Histopathological examination revealed degenerative enteric neuropathy, possibly secondary to chronic ischemia.

The presence and distribution of S-100 protein antigen and lysozyme were investigated by the immunoperoxidase method in paraffin sections of 13 cases of chronic cutaneous leishmaniasis from Saudi Arabia. Varying numbers of S-100+lys- histiocytic reticulum cells were found in the dense inflammatory infiltrate in 11 out of 13 cases. These cells were considerably more numerous in the lesions dominated by cells of the mononuclear phagocytic system and granulomata than in the cases with plasma cellular or lymphocytic predominance. Activated lys+ macrophages, epithelioid cells, and multinucleated giant cells were always S-100-. Around the granulomata several S-100+lys- histiocytic reticulum cells could be found. These findings suggest that antigen-presenting cells are present in the inflammatory infiltrate of cutaneous leishmaniasis.

A Binkhorst iridocapsular intraocular lens was implanted into an eye of a patient after an extracapsular cataract extraction. The patient died 4 months after surgery of gastric cancer. The eye was obtained for histopathologic examination at the autopsy. The superior loop was inside the residual capsular bag causing no damage to the iris and ciliary body. The inferior loop, however, was found outside the capsular sac and caused depression of the iris tissue but neither inflammation nor scarring of the iris had developed. These findings emphasize the importance of the location of iridocapsular intraocular lenses which can cause mechanical damage to the supporting tissues if the loops are not placed inside the capsular bag.

Background and Aims: Small bowel manometry is increasingly used in the clinical investigation of patients with symptoms of intestinal motor dysfunction. Enteric dysmotility (ED) has been suggested as a new diagnostic term for patients with abnormal intestinal motor activity but no radiological signs of chronic intestinal pseudo-obstruction (CIP). Histopathological features of adult patients with ED and CIP have been compared in a large case series to study differences and similarities between the two diagnostic groups. Methods: Routine staining and an extensive panel of immunohistochemical stains on transversal and tangential cuts from full-thickness biopsies of the small bowel were used. Results: 39 females and 11 males with CIP and 58 females and 7 males with ED were investigated. The underlying lesion was more often a visceral myopathy (22% vs 5%) or neuromyopathy (30% vs 12%) in patients with CIP than in those with ED, whereas the predominant lesion in ED was neuropathy with inflammation. Conclusion: CIP in adults is associated with very different underlying pathology, whereas ED is more homogeneously associated with neuropathy in the enteric nervous system. Neuropathy of enteric ganglia with inflammation seems to be the most common cause for measurable disturbances of intestinal motor function.

AR-C117977, a monocarboxylate transporter inhibitor, reduces immune responses both in vitro and in vivo, maintains long-term graft survival, and induces operational tolerance. To evaluate the immunosuppressive limitations of AR-C117977, this study was performed in nonvascularized transplant models noted for their refractive response to standard immunosuppressive agents. Rat skin was transplanted from DA(RT1avl) into PVG(RT1c) and the reverse. Mouse islet allotransplantation was performed with BALB/c H2d donors and C57Bl/6J H2b recipients. In the skin graft model, AR-C117977 monotherapy was associated with long-term skin graft survival in one rat strain combination. AR-C117977 and cyclosporine A (CsA) in combination resulted in significant prolongation of graft survival in both rat strains. CsA monotherapy did not prevent acute rejection in either strain. Islet allograft survival was moderately prolonged with CsA or AR-C117977. AR-C117977 is an efficient immunosuppressive drug in stringent rodent transplant models and further studies are warranted.

Advances in minimally invasive surgery have made laparoscopy and full-thickness bowel biopsy possible in the investigation of patients with suspected gastrointestinal neuromuscular disorders. The safety and diagnostic yield of this investigation have not been formally reported. A prospective study was undertaken of 124 patients with clinico-physiological diagnoses of chronic intestinal pseudo-obstruction, enteric dysmotility and severe irritable bowel syndrome undergoing LFTB in three European teaching centres with expertise in the management of gastrointestinal neuromuscular disorders. Perioperative data were collected including complications. Diagnostic yield was expressed as proportion with well-established specific neuromuscular abnormalities based on a protocol of routine and immunohistochemical techniques. The majority of patients underwent a laparoscopically assisted procedure with extracorporeal biopsy. Median operating time was 50 min, conversion rate 2% and length of stay 1 day. There was an 8% readmission rate for obstructive symptoms but minimal other morbidity and no mortality. Overall specific diagnostic yield was 81%, being high for jejunal biopsies (89%) but low for a small number of ileal and colonic biopsies. Laparoscopy and full-thickness biopsy of the bowel appears acceptable in terms of safety. It should be performed in a jejunal site to achieve a high diagnostic yield.

Little is known about the enteric ganglionic system in subjects with gastrointestinal dysmotility syndrome (GIDS). Furthermore, dysfunction of gastrointestinal motility is an early complaint of subjects with Parkinson’s disease. Here, we assessed p62/sequestosome-1(p62) and α-synuclein (αS) immunoreactivity (IR) in full-thickness bowel specimens of the gut obtained from six subjects with GIDS and from 17 controls. In the myenteric neurons, fine punctuate p62-IR were seen in all of the controls, whereas diffuse cytoplasmic and nuclear p62-IR were seen in the GIDS cases. Physiological αS-IR (clone 42/αS) was seen in all of the controls and the GIDS cases in the lamina propria, the submucosal and in the myenteric plexuses. The disease associated αS (clone 5G4) labeled the cytoplasm of the ganglion cells only in the myenteric plexus in three out of the four subjects with the GIDS/inflammatory neuropathy. In summary, ganglion cells were readily visualized in all of the layers of the bowel with clone 42/αS, and p62 displayed altered patterns of labeling in subjects with the GIDS. Labeling seen with the disease associated clone 5G4/αS in the GIDS/inflammatory neuropathy is intriguing and might indicate that the alteration of αS is triggered by a chronic inflammation.

Background: An increased prevalence of irritable bowel syndrome (IBS) and disturbances in cardiac and blood pressure reflexes have been described in patients with Crohn's disease (CD) and ulcerative colitis (UC). These features could be due to abnormalities in the gastrointestinal neurotransmission. The aims of this study were to examine whether histopathologic changes in the enteric nervous system correlate with disturbances in cardiac and blood pressure reflexes and the occurrence of IBS- and dyspepsia-like symptoms in these patients. Methods: Thirty patients with CD and UC with bowel resection were examined by deep-breathing and orthostatic tests. The resection specimens were evaluated histologically regarding visceral neuro- or myopathy. All medical records were studied for treatment and clinical course. Results: Ganglioneuritis was observed in 11 of 19 patients with CD and in 5 of 11 with UC. Only patients with CD had ganglioneuritis in the small intestine. Moreover, in CD the interstitial cells of Cajal (ICCs) in the small bowel showed atrophy and vacuolar degeneration, along with a reduced number of cells (P = 0.005). In UC the colonic ICCs were hyperplastic (P = 0.05) without signs of degeneration. The indices of deep-breathing and orthostatic tests were impaired, except in CD with ganglioneuritis, who showed normal test values. There were no correlations between histopathologic alterations versus IBS and dyspepsia. Conclusions: Visceral ganglioneuritis and pathologic ICCs were observed in patients with CD and UC. However, these histopathologic abnormalities could not be related to the clinical or autonomic features of the disease.

Food supplements are known to affect the development of gastric adenocarcinoma. In this study, an animal model of gastric resection was used to investigate the effects of calcium carbonate on spontaneous development of gastric adenocarcinoma.Ninety-two Wistar rats with gastric resections (performed to induce spontaneous gastric cancer) and 60 without resections (controls) were used to analyse the carcinogenic potential of different ion supplements in food.Among the resected rats, cancer developed in 3 out of 18 (17%, NS) given NaCl but in 11 out of 18 (61%, p0.01) exposed to calcium carbonate. No tumours were found in the unresected (unoperated) animals. These findings were further analysed by separately investigating the effects of calcium and carbonate ions on tumorigenesis in the gastric stump model. Cancer developed in one of 26 (4%) resected animals given a diet supplemented with CaHPO(4), which was lower than the rate observed in the resected control group fed a normal diet, although this difference was not statistically significant. However, tumour development increased significantly in the resected animals given a diet supplemented with NaHCO(3) (tumours in 13 out of 24 rats, 54%; p0.01).The present results reveal a significant role for carbonate in the induction of gastric carcinoma in the rat. The relevance of this finding is underlined by the fact that carbonate is a major constituent of intestinal reflux into the stomach, and that such reflux is considered to be one of the major causes of gastric cancer.

Patients with ulcerative colitis and primary sclerosing cholangitis have an increased risk of developing carcinoma both in the bile ducts and in the colon.To investigate whether this patient group also has an increased risk of developing atrophy and neoplasia in the ileal pouch mucosa after construction of a pelvic pouch with an ileoanal anastomosis or a continent Kock ileostomy.Flexible video endoscopic examinations of the ileal pouch were performed in 16 patients with ulcerative colitis and primary sclerosing cholangitis and in 16 matched patients with ulcerative colitis without sclerosing cholangitis. Biopsies were sampled from different locations in the pouch for histologic assessment of mucosal atrophy and dysplasia and for flow cytometric DNA analysis assessing chromosomal aberrations.The patients with sclerosing cholangitis developed moderate or severe atrophy in the pouch significantly more often (P0.01). Persistent severe mucosal atrophy was revealed in eight patients with sclerosing cholangitis and only in two controls. One patient with sclerosing cholangitis had high-grade dysplasia in multiple locations. Low-grade dysplasia was assessed in three patients with sclerosing cholangitis and in two of the controls. DNA aneuploidy was displayed in three patients, all with sclerosing cholangitis and dysplasia. All patients with neoplastic transformation had a pouch with ileoanal anastomosis and a long pouch duration (8 years).Patients with ulcerative colitis and primary sclerosing cholangitis with an ileal reservoir are more prone to developing mucosal atrophy in the pouch and seem to have a higher risk of neoplastic transformation in the pouch mucosa than patients with ulcerative colitis without sclerosing cholangitis.

Background: Flat and depressed colorectal tumours are common in Japan but are very rare or non-existent in Western countries. Aims: To study the occurrence of flat colorectal tumours in a southern Swedish population. Methods: In this prospective study, 371 consecutive European patients were examined by high resolution video colonoscopy combined with chromoendoscopy. The nature of the lesions was determined by histopathological examination. Results: A total of 973 tumours were found; 907 (93.2%) were protruding and 66 (6.8%) were flat or depressed. Of the flat/depressed tumours, five (7.7%) were early adenocarcinomas infiltrating the submucosa. Eleven carcinomas (1.2%) were found among protruding tumours. High grade dysplasia was observed in 18% (n=11) of flat/depressed adenomas in contrast with 7.3% (n=65) of protruding adenomas, and occurred in smaller flat/depressed tumours compared with protruding ones (mean diameter 8 mm v 23 mm, respectively). Furthermore, high grade dysplasia was significantly more common in flat elevated tumours with central depression or in depressed adenomas (35.7%; 5/14) than in flat elevated adenomas (12.8%; 6/47). Conclusion: Flat and depressed tumours exist in a Western population. Future studies should address whether or not chromoendoscopy with video colonoscopy is necessary in the search for flat colorectal neoplasms.

• The aim was to further characterize the enteric histopathological changes in a rat model.

Background: In a small subgroup of patients with ulcerative colitis (UC) undergoing proctocolectomy and restorative ileal pouch-anal anastomosis (IPAA), a colonic-like pouch mucosa with severe and persistent villous atrophy (type C pattern) develops. Neoplastic transformation of the mucosa in the neorectum may occur in these patients. We hypothesized that genetic alterations associated with colorectal carcinoma (CRC) could be an early finding in this transformational process and thus potentially useful as clinical monitors in carcinoma risk assessment. Methods: In six patients with long-standing severe pouchitis and a type C-pattern mucosa, biopsies were obtained from five different locations of the pouches. DNA was PCR-amplified and analyzed by automated fragment analysis for loss of heterozygosity (LOH) at chromosome 5q14–22, 17p12–13, and 18q12–22. Point mutations of the K-ras and adenomatous polyposis coli (APC) genes were studied by sequencing. Results: The patients had varying degrees of dysplasia and one displayed DNA aneuploidy. Loss of heterozygosity at 5q15–22 was detected in three of five biopsies in one patient. This particular patient had no signs of dysplasia or DNA aneuploidy and a normal exon 15 sequence of the APC gene. No alterations of either the K-ras or the APC genes or LOH of 5q, 17p, or 18q were seen in any of the other patients. Conclusion: Dysplasia, aneuploidy, and LOH in 5q may all reflect different parts of an atrophic mucosa-dysplasia-carcinoma sequence, in line with current concepts of carcinogenesis for CRC in longstanding pouchitis. Further studies of histological and molecular events in IPAA patients with severe atrophy are warranted.

Vascular changes are considered the major histopathological indicator of chronic allograft dysfunction. These changes are characterized by intimal thickening caused by accumulation of primarily smooth muscle cells. Contributing factors may be of both immunological and nonimmunological origin. Cold ischemia has been shown to trigger intimal proliferation in the absence of alloantigen in an isogenic rat aortic transplant model. We have used this model to investigate the impact of inhibition of tissue factor (TF) signalling on the progression of intimal thickening. Group 1 was treated with recombinant FVIIa inhibited in its active site (rFVIIai), and group 2 served as untreated controls. At 8 weeks the intimal area was measured with image analysis. Medial areas and the proportion of medial necrosis were determined. Animals treated with rFVIIai showed significantly less intimal thickening compared with controls: median 0.147 vs. 0.256 mm2, respectively (p = 0.008). A positive correlation between intimal hyperplasia and medial necrosis (r(s) = 0.79, p = 0.01), as well as adventitial inflammation (r(s) = 0.83, p = 0.009), was found. TF mRNA was not detected in the neointima at 8 weeks, as determined by in situ hybridization. We conclude that active site inhibited FVIIa (rFVIIai) given prior to and directly after implantation of aortic transplants significantly reduces intimal hyperplasia caused by nonimmunological factors in this model.

Serum samples from patients referred for liver biopsy for investigation of suspected chronic liver disease (n = 286) and from healthy middle-aged volunteers (n = 445) were analyzed for markers of exposure to GB virus C/hepatitis G virus (GBV-C/HGV), hepatitis B virus and hepatitis C virus. GBV-C/HGV analyses included GBV-C/HGV PCR for detection of viremia and GBV-C/HGV enzyme-linked immunosorbent assay for anti-GBV-C/HGV E2 antibodies. Liver biopsies were re-evaluated by a hepatopathologist. GBV-C/HGV markers were detected in 97/286 (34%) patients (GBV-C/HGV RNA = 26; anti-GBV-C/HGV E2 antibodies = 74) compared to 86/445 (19%; p < 0.0001) controls (GBV-C/HGV RNA = 7, anti-GBB-C/HGV E2 antibodies = 79). A significantly higher proportion of GBV-C/HGV-exposed subjects in the patient group were viremic compared to controls (27% vs. 8.1%; p = 0.0015). GBV-C/HGV markers were more commonly found in patients with chronic hepatitis B and C. In patients with GBV-C/HGV viremia, a higher occurrence of bile duct degeneration was detected than in non-viremic patients. Markers of GBV-C/HGV infection were over-represented among patients investigated for chronic liver disease, and ongoing GBV-C/HGV viremia was more common in this group than in controls. Apart from a higher prevalence of bile duct degeneration in viremic patients, infection with GBV-C/HGV did not confer any specific histological characteristics.

The immune responses in actinomycetoma lesions caused by Streptomyces somaliensis in Sudan were characterized by immunohistochemistry during 1997-1998. In sections stained with haematoxylin and eosin, the inflammatory reaction around the grain was of 2 types. In type I there were 3 zones: a neutrophil zone immediately around the grain, an intermediate zone containing mainly macrophages, and a peripheral zone consisting of lymphocytes and plasma cells. Zone 1 stained positively for CD15 (neutrophils), zone 2 for CD68 (macrophages) and CD3 (T lymphocytes), and zone 3 for CD20 (B lymphocytes). In the type II reaction, there was no neutrophil zone, the grains being surrounded only by macrophages and giant cells. This was confirmed by immunohistochemistry, which demonstrated the presence of CD3 positive cells. Immunoglobulins G and M and complement were demonstrated on the surface of the grain and on filaments inside the grain. Neutrophils and macrophages were recruited into the lesion by complement and were involved in the fragmentation of the grain. The cytokine profile in the lesion and regional lymph nodes was of a dominant Th2 pattern (interleukins-10 and 4).

OBJECTIVE: Patients with extensive and long-standing ulcerative colitis have an increased risk of developing colorectal cancer and sub-epithelial fibrosis. The polypeptide transforming growth factor alpha (TGF-alpha) has mitogenic effects and it is believed that local overproduction may result in tumour formation and fibrosis. DESIGN: In the present study, we correlated the presence of TGF-alpha in ulcerative colitis with the degree of inflammation and with dysplasia. METHODS: Sixty two patients were investigated, 46 with ulcerative colitis (16 with active inflammation and 20 in remission, 10 with dysplasia of the colon), and 16 controls with normal colonoscopy and without a history of colitis. There were no overlaps between the subgroups. Tissue sections from colonic biopsies were examined and TGF-alpha was detected by immunohistochemistry. TGF-alpha-containing cells were characterized by double-staining with antibodies to eosinophil cationic protein (ECP). An antibody (EG2) recognizing eosinophils with an activated phenotype was also used. RESULTS: The median number of TGF-alpha-containing cells in the mucosa was 24 per mm2 (inter-quartile range 10-51) in controls, 186 per mm2 (73-245) in ulcerative colitis with active inflammation, 76 per mm2 (52-198) in remission, and 130 per mm2 (66-203) in areas of dysplasia. Double-staining for TGF-alpha and ECP revealed that most of the TGF-alpha-containing cells were eosinophils, and most had an activated phenotype as judged by staining with EG2. CONCLUSIONS: The presence of TGF-alpha-containing cells in colonic mucosa is increased both in active inflammation and during remission in ulcerative colitis. Dysplasia is not associated with any significant increase in TGF-alpha-containing cells. The majority of TGF-alpha-containing cells are eosinophils with an activated phenotype. TGF-alpha released from these cells could be important for the development of complications seen in ulcerative colitis, such as cancer and fibrosis. (Less)

A 26-year-old previously healthy woman developed granulomatous pneumonitis, encephalitis, and genital ulceration during primary Epstein-Barr virus (EBV) infection. EBV DNA was demonstrated by polymerase chain reaction analysis of serum, lung tissue, and genital ulcer specimens. Serology verified primary EBV infection. The patient lacked lymphocytes cytotoxic to autologous EBV-transformed B lymphocytes. No spontaneous or in vitro EBV-induced interferon gamma (IFN-gamma) production was evident in peripheral blood. The cells had normal IFN-gamma production when stimulated with Staphylococcus aureus exotoxin A. In the bone marrow and peripheral blood, the number of large granular CD56+ lymphocytes (natural killer cells) increased 39%-55%, but no CD4 or CD8 cell lymphocytosis was initially found. A partial clinical response was achieved with treatment with acyclovir, corticosteroids, and intravenous gamma-globulin. Because of persistent granulomatous central nervous system and lung involvement, subcutaneous IFN-gamma therapy was started but was discontinued after 3 months because of development of fever, pancytopenia, and hepatitis. This therapy initiated a complete clinical recovery, which occurred parallel to development of EBV-specific cytotoxic CD8+ T lymphocytes and normalization of natural killer cell lymphocytosis. These findings provide evidence for an EBV-induced lymphoproliferative disorder due to a T lymphocyte dysfunction associated with a selective lack of IFN-gamma synthesis.

Purpose: To determine the sensitivity and specificity of X-ray mammography and of MR imaging in 238 consecutively operated breasts, and to correlate the findings to histopathological diagnosis. Material and Methods: Over 15 months, 220 patients scheduled for breast surgery were examined consecutively, before surgery, by means of both mammography and MR imaging. of the 220 patients, 18 underwent bilateral breast surgery. The entire breast was examined by means of T1-weighted transversal images using a 3D fast low-angle shot (FLASH) sequence. One pre— and 2 post-contrast scans were performed. Each breast was examined by means of mammography and 3 views were applied as routine. All palpable and mammographically suspect lesions were examined on additional images as microfocus magnification or spot compression. The two methods were evaluated independently of each other. Results: In total, 145 malignant and 93 benign lesions were found at histopathological examination. The sensitivity of mammography was 89% and MR imaging 92%. The specificity was 72% in both methods. When the results of the 2 methods were combined, a sensitivity of 99% and a specificity of 55% was achieved. Conclusion: Mammography and MR imaging seemed to complement each other to produce a high sensitivity. Unfortunately it is impossible at present to supplement mammography with MR imaging in each patient as a routine owing to the current technical and financial limitations.

A-36-year-old man presented with classic symptoms of a glomus tumour in the right index finger that failed to show on either ultrasound or high resolution magnetic resonance imaging (MRI). The radial finger pulp was explored despite the radiological findings and a glomus tumour 2 mm in size was excised. At follow-up the patient was pain-free. We conclude that exploration of an affected fingertip should be considered when there is a history of suspected glomus tumour even if MRI shows no sign of disease.

Purpose: The aim of our prospective study was to determine the diagnostic accuracy of MR mammography (MRM) in detecting malignant disease. Material and Methods: In 231 consecutive patients scheduled for surgery because of mammographic or palpable lesions suspected of malignancy, the breasts were examined with T1-weighted transversal images using a 3-D fast low angle shot (FLASH) sequence. One pre- and 2 post-contrast images were obtained. Histological examination of the surgical specimens showed carcinoma in 155 breasts, of which 138 were invasive and 17 in situ. Results: MRM detected 144 of the 155 malignancies and was false-negative in 11 cases. Eight of these MRM-missed tumours were invasive and 3 were in situ cancers. Benign lesions were found at microscopy in 95 breasts, of which MRM correctly diagnosed 69. The cellular composition of the 26 false-positive lesions (myxomatous stromal change, high vascularity, and epithelial or apocrine hyperplasia) might explain the false positivity. The sensitivity and specificity of MRM were 93% and 73%, respectively. Conclusion: MRM should be interpreted with caution, and supplemented with e.g. mammography and ultrasonography.

Primary sclerosing cholangitis (PSC) is a biliary destructive disease mostly affecting patients with ulcerative colitis (UC). PSC has been suggested to be an independent risk factor for the development of colorectal malignancy in UC. Patients with PSC also have an increased risk of developing cholangiocarcinoma. This study aimed at assessing the cumulative risk of colorectal neoplasia in PSC and UC, and also to determine risk factors for the development of cholangiocarcinoma. Fifty-eight PSC patients were included. Forty PSC patients having extensive UC were each matched to two control patients of the same age, with extensive colitis and a comparable duration of the colitis, but without PSC. All UC patients had been under colonoscopic surveillance with multiple biopsies. Among the 40 PSC patients with UC, 16 developed colonic dysplasia or carcinoma, versus 10 in the control group (P < .001). The absolute cumulative risk of developing colorectal dysplasia/carcinoma in the PSC/UC groups was 9%, 31%, and 50% after 10, 20, and 25 years of disease duration. In the group with UC only, the corresponding risk was 2%, 5%, and 10%, respectively (P < .001). Ten patients with PSC developed cholangiocarcinoma, all but one having UC. In the control group, no cholangiocarcinoma occurred. Patients with PSC and UC with colorectal neoplasia developed cholangiocarcinoma significantly more often compared with patients with UC and PSC without colonic dysplasia/carcinoma (P < .02). This study demonstrates not only that patients with PSC and UC have a significantly higher risk of developing colorectal neoplasia compared with patients having UC only, but also that patients with PSC and UC having colorectal neoplasia are more prone to develop cholangiocarcinoma.

Primary sclerosing cholangitis (PSC) is a biliary destructive disease mostly affecting patients with ulcerative colitis (UC). PSC has been suggested to be an independent risk factor for the development of colorectal malignancy in UC. Patients with PSC also have an increased risk of developing cholangiocarcinoma. This study aimed at assessing the cumulative risk of colorectal neoplasia in PSC and UC, and also to determine risk factors for the development of cholangiocarcinoma. Fifty-eight PSC patients were included. Forty PSC patients having extensive UC were each matched to two control patients of the same age, with extensive colitis and a comparable duration of the colitis, but without PSC. All UC patients had been under colonoscopic surveillance with multiple biopsies. Among the 40 PSC patients with UC, 16 developed colonic dysplasia or carcinoma, versus 10 in the control group (P < .001). The absolute cumulative risk of developing colorectal dysplasia/carcinoma in the PSC/UC groups was 9%, 31%, and 50% after 10, 20, and 25 years of disease duration. In the group with UC only, the corresponding risk was 2%, 5%, and 10%, respectively (P < .001). Ten patients with PSC developed cholangiocarcinoma, all but one having UC. In the control group, no cholangiocarcinoma occurred. Patients with PSC and UC with colorectal neoplasia developed cholangiocarcinoma significantly more often compared with patients with UC and PSC without colonic dysplasia/carcinoma (P < .02). This study demonstrates not only that patients with PSC and UC have a significantly higher risk of developing colorectal neoplasia compared with patients having UC only, but also that patients with PSC and UC having colorectal neoplasia are more prone to develop cholangiocarcinoma.

The colorectal biopsy specimens from 30 patients with chronic watery diarrhoea but normal endoscopic and radiographic findings were studied by light microscopy, morphometry, immunohistochemistry, and two patients with electron microscopy. The histological changes in the colorectum were originally diagnosed in six patients as lymphocytic colitis and in 24 patients as collagenous colitis. The analysis of the specimens for this study could delineate three distinct groups of microscopic colitis: lymphocytic colitis (six patients), collagenous colitis without lymphocytic attack on the surface epithelium (seven patients), and a mixed form presenting with both thickening of the collagen plate and increased number of intraepithelial lymphocytes (17 patients). No transformation was seen from one type to another during follow up of six patients for four to seven years. Increased numbers of active pericryptal myofibroblasts were found with the electron microscope in one patient with mixed microscopic colitis showing also myofibroblasts entrapped within the collagen layer. Hitherto undescribed flat mucosa of the ileum was found in one patient with lymphocytic colitis and both flat mucosa and thickening of the collagen plate in the ileum were seen in one patient with the mixed form of the disease. In another patient with mixed microscopic colitis, normalisation of the colorectal morphology occurred after temporary loop ileostomy, followed by the reappearance of both diarrhoea, inflammation, and thickening of the collagen plate after the ileostomy was reversed. No association was found between non-steroid anti-inflammatory drug (NSAID) consumption and collagenous or mixed microscopic colitis. The primary cause of microscopic colitis is probably an immunological reaction to luminal antigen/s, perhaps of ileal origin. The engagement of the pericryptal myofibroblasts in the disease process might result in the development of the various forms of microscopic colitis. An inverse relation between intraepithelial lymphocyte count and collagen thickness may indicate that microscopic colitis is a spectral disease.

Objective: Many patients, especially women, suffer from severe gastrointestinal pain and dysmotility for several years without being diagnosed. Depletion of gonadotropin-releasing hormone (GnRH) in the enteric nervous system (ENS) has been described in some patients. The aim of this study was to examine the expression of GnRH in ENS and antibodies against GnRH in serum, in a dysmotility patient cohort of southern Sweden. Materials and methods: All consecutive patients (n = 35) referred for laparoscopic full-thickness biopsy because of symptoms or signs of severe dysmotility between 1998 and 2009, or patients with a severe dysmotility disorder having had a bowel resection within the time frame, were considered for inclusion. In 22 cases, representative biopsy material containing ganglia was available, and these patients were included. Medical records were scrutinized. The expression of GnRH was determined by immunohistochemistry in bowel biopsies from these patients and in patients with carcinoma or diverticulosis without ENS histopathology. Antibodies against GnRH in serum were determined by ELISA in patients and controls. Results: 14 patients were diagnosed with enteric dysmotility (ED) and 8 with chronic intestinal pseudo-obstruction due to varying etiology. Immunostained biopsies showed expression of GnRH in the ENS. A reduced expression of GnRH-containing neurons was found in 5 patients, as well as antibodies against GnRH in serum. 3 of these patients had a history of in vitro fertilization (IVF) using GnRH analogs. Conclusions: A subgroup of patients with severe dysmotility had a reduced expression of GnRH-containing neurons in the ENS and expressed antibodies against GnRH in serum.

Leuprolide is a gonadotropin-releasing hormone (GnRH) analog which has been shown to reduce symptoms in patients with irritable bowel syndrome (IBS) and chronic intestinal pseudo-obstruction (CIPO). The mechanism is not known, but one hypothesis is through down-modulation of luteinizing hormone (LH) secretion, a hormone whith antagonistic effect on gastrointestinal motility. However, presence of LH receptors in the gastrointestinal tract has never been described. The aim of this study was to find one possible way of action for leuprolide by examining the presence of the LH receptor, and if present, to see whether there was different expression in patients with or without dysmotility. Full-thickness biopsies from the bowel wall of patients with and without severe dysmotility were examined using immunohistochemistry staining. Biopsies showed expression of LH receptors on myenteric neurons and in glial cells, neutrophils, endothelial cells and mast cells. There was no difference in expression between patient groups.

Two cases of primary hyperparathyroidism with underlying parathyroid adenomas were found to be associated with lymphocytic infiltration and destruction of the neoplastic tissue. There was no inflammatory infiltrate in the adjacent rim of the remnant of parathyroid gland or in the other tumour-free glands. The lymphoid cell population within the tumours was composed of both infiltrating T-cells and compact nodule-forming B-cells. In one of the tumours there was considerable fibrosis and atrophy of the adenomatous tissue. The histological picture was consistent with an autoimmune process directed against the adenomas, indicating that this reaction had, in part, been successful in reducing the abnormal cell population.

Background Patients with gastrointestinal neuromuscular diseases may undergo operative procedures that yield tissue appropriate to diagnosis of underlying neuromuscular pathology. Critical to accurate diagnosis is the determination of limits of normality based on the study of control human tissues. Although robust diagnostic criteria exist for many qualitative alterations in the neuromuscular apparatus, these do not include quantitative values due to lack of adequate control data. Purpose The aim of this report was to summarize all relevant available published quantitative data for elements of the human enteric nervous system (neuronal cell bodies, glial cells, and nerve fibers) from the perspective of the practicing pathologist. Forty studies meeting inclusion criteria were systematically reviewed with data tabulated in detail and discussed in the context of methodological variations and limitations. The results reveal a lack of concordance between observations of different investigators resulting in data insufficient to produce robust normal ranges. This diversity highlights the need to standardize the way pathologists collect, process, and quantitate neuronal and glial elements in enteric neuropathologic samples, as suggested by recent international guidelines on gastrointestinal neuromuscular pathology. (Less)

The aim of the study was to analyse the agreement between pathologists regarding macroscopic autopsy diagnostics. Four pathologists examined 35 autopsies and determined the principal disease and its complications, the immediate cause of death, other major diseases and their complications, and minor diseases. The participants were paired and their diagnoses were analysed by using kappa statistics for interobserver variation. The agreement on the principal disease was almost perfect between the participants (kappa values between 0.83 and 0.97), whereas that on the immediate cause of death was moderate/substantial (kappa values between 0.43-0.75). The list of all other major diseases and their complications was almost complete for each observer, but that of the minor diseases showed a more considerable variation. In spite of the high level of agreement it is recommended that the autopsy findings be discussed among pathologists if the clinical picture cannot be explained satisfactorily, and that the cause of death be determined by the clinicians after the demonstration of the autopsy.

A retrospective analysis of 3042 autopsies was carried out to determine and compare the discrepancy rates between clinical and autopsy diagnoses as well as the sensitivity and specificity of clinical diagnostics in 10 diseases in 1977/78 and 1987/88. The autopsy rate decreased from 80% to 39%, which might explain the increased discrepancy rate from 22% to 27% regarding the diagnoses of major, principal diseases. The accuracy of clinical diagnostics seemed to improve during the period for some of the diseases (pulmonary embolism, peptic ulcer, infectious carditis, peritonitis), while it worsened for others (acute myocardial infarction, thrombosis of the mesenteric artery, ruptured aortic aneurysm, tuberculosis) or remained unchanged (cirrhosis of the liver, malignant tumours regarded as a whole group). The findings underline the importance of autopsies and their cumulative studies in assessing the accuracy and providing data for the determination of necessary fallibility of clinical diagnostics.

Objective Guidelines on histopathological techniques and reporting for adult and paediatric gastrointestinal neuromuscular pathology have been produced recently by an international working group (IWG). These addressed the important but relatively neglected areas of histopathological practice of the general pathologist, including suction rectal biopsy and full-thickness intestinal tissue. Recommendations were presented for the indications, safe acquisition of tissue, histological techniques, reporting and referral of such histological material. Design Consensual processes undertaken by the IWG and following established guideline decision group methodologies. Results and conclusion This report presents a contemporary and structured classification of gastrointestinal neuromuscular pathology based on defined histopathological criteria derived from the existing guidelines. In recognition of its origins and first presentation in London at the World Congress of Gastroenterology 2009, this has been named ‘The London Classification’. The implementation of this classification should allow some diagnostic standardisation, but should necessarily be viewed as a starting point for future modification as new data become available.

Background Inflammation and immune activation have repeatedly been suggested as pathogentic factors in irritable bowel syndrome (IBS). The driving force for immune activation in IBS remains unknown. The aim of our study was to find out if the obligate intracellular pathogen Chlamydia could be involved in the pathogenesis of IBS. Methods We studied 65 patients (61 females) with IBS and 42 (29 females) healthy controls in which IBS had been excluded. Full thickness biopsies from the jejunum and mucosa biopsies from the duodenum and the jejunum were stained with a monoclonal antibody to Chlamydia lipopolysaccharide (LPS) and species-specific monoclonal antibodies to C. trachomatis and C. pneumoniae. We used polyclonal antibodies to chromogranin A, CD68, CD11c, and CD117 to identify enteroendocrine cells, macrophages, dendritic, and mast cells, respectively. Results Chlamydia LPS was present in 89% of patients with IBS, but in only 14% of healthy controls (p < 0.001) and 79% of LPS-positive biopsies were also positive for C. trachomatis major outer membrane protein (MOMP). Staining for C. pneumoniae was negative in both patients and controls. Chlamydia LPS was detected in enteroendocrine cells of the mucosa in 90% of positive biopsies and in subepithelial macrophages in 69% of biopsies. Biopsies taken at different time points in 19 patients revealed persistence of Chlamydia LPS up to 11 years. The odds ratio for the association of Chlamydia LPS with presence of IBS (43.1; 95% CI: 13.2-140.7) is much higher than any previously described pathogenetic marker in IBS. Conclusions We found C. trachomatis antigens in enteroendocrine cells and macrophages in the small bowel mucosa of patients with IBS. Further studies are required to clarify if the presence of such antigens has a role in the pathogenesis of IBS.

Intestinal lymphocytic epithelioganglionitis: a unique combination of inflammation in bowel dysmotility: a histopathological and immunohistochemical analysis of 28 cases Visceral inflammatory neuropathies are enteric disorders underlying various forms of bowel dysmotility. The aim was to analyse the microscopic characteristics of a unique combination of intraepithelial lymphocytosis and myenteric ganglioneuritis. Paraffin sections of full-thickness proximal jejunal biopsy specimens from 28 patients, with proven disorders of gastrointestinal motility, were analysed following conventional and immunohistochemical staining. Serial transversal and tangential sectioning visualized large myenteric plexus areas. Between 1993 and 2005, 28 patients with inflammatory neuropathy (25 female and three male) showed this combination of lymphocytic infiltration. Two of the patients also had coeliac disease. The mean number of intraepithelial CD3+ lymphocytes was 36 per 100 epithelial cells (range 27-68; upper normal limit 25 lymphocytes). There was myenteric ganglionitis of variable severity (mean 4.6 myenteric lymphocytes per ganglion; upper normal limit two lymphocytes) with cytotoxic T-cell predominance. Myenteric neurons showed signs of degeneration and an abnormal immunohistological pattern. Hyperplasia and hypertrophy of Cajal cells were observed. The longitudinal muscle layer was thickened in many cases. A subset of patients with gastrointestinal motility disorders exhibit the combination of intraepithelial lymphocytosis and myenteric ganglionitis in full thickness biopsy specimens of the small bowel. We suggest calling this entity 'intestinal lymphocytic epithelioganglionitis'. (Less)

Background Antibodies against gonadotropin-releasing hormone (GnRH) and gastrointestinal dysmotility have been found after treatment with GnRH analogues. The aim of this study was to examine the presence of such antibodies in patients with dysmotility not subjected to GnRH treatment and study the anti-GnRH antibody effect on enteric neurons viability in vitro. Methods Plasma and sera from 3 patients suffering from either enteric dysmotility, irritable bowel syndrome (IBS) or gastroparesis were analysed for C-reactive protein (CRP), and for GnRH antibodies and soluble CD40 by ELISA methods. Primary cultures of small intestinal myenteric neurons were prepared from rats. Neuronal survival was determined after the addition of sera either from the patients with dysmotility, from healthy blood donors, antiserum raised against GnRH or the GnRH analogue buserelin. Only for case 1 a full-thickness bowel wall biopsy was available for immunohistochemical analysis. Results All 3 patients expressed antibodies against GnRH. The antibody titer correlated to the levels of CD40 (rs = 1.000, p < 0.01), but not to CRP. Serum from case 3 with highest anti-GnRH antibody titer, and serum concentrations of sCD40 and CRP, when added to cultured rat myenteric neurons caused remarkable cell death. In contrast, serum from cases 1 and 2 having lower anti-GnRH antibody titer and lower sCD40 levels had no significant effect. Importantly, commercial antibodies against GnRH showed no effect on neuron viability whereas buserelin exerted a protective effect. The full-thickness biopsy from the bowel wall of case 1 showed ganglioneuritis and decrease of GnRH and GnRH receptor. Conclusion Autoantibodies against GnRH can be detected independently on treatment of GnRH analogue. Whether the generation of the antibody is directly linked to neuron degeneration and chronic gastrointestinal symptoms in patients with intestinal dysmotility, remains to be answered.

The term gastrointestinal neuromuscular disease describes a clinically heterogeneous group of disorders of children and adults in which symptoms are presumed or proven to arise as a result of neuromuscular, including interstitial cell of Cajal, dysfunction. Such disorders commonly have impaired motor activity, i.e. slowed or obstructed transit with radiological evidence of transient or persistent visceral dilatation. Whilst sensorimotor abnormalities have been demonstrated by a variety of methods in these conditions, standards for histopathological reporting remain relatively neglected. Significant differences in methodologies and expertise continue to confound the reliable delineation of normality and specificity of particular pathological changes for disease. Such issues require urgent clarification to standardize acquisition and handling of tissue specimens, interpretation of findings and make informed decisions on risk-benefit of full-thickness tissue biopsy of bowel or other diagnostic procedures. Such information will also allow increased certainty of diagnosis, facilitating factual discussion between patients and caregivers, as well as giving prognostic and therapeutic information. The following report, produced by an international working group, using established consensus methodology, presents proposed guidelines on histological techniques and reporting for adult and paediatric gastrointestinal neuromuscular pathology. The report addresses the main areas of histopathological practice as confronted by the pathologist, including suction rectal biopsy and full-thickness tissue obtained with diagnostic or therapeutic intent. For each, indications, safe acquisition of tissue, histological techniques, reporting and referral recommendations are presented.

A histomorphologic study of the pelvic pouch mucosa during the first two years of function was performed in 11 consecutive patients treated for ulcerative colitis. Two types of mucosal adaptation were delineated. Type A response (5 patients) showed stable slight atrophy, normal numbers of goblet cells, and numerous sulphated mucin positive cells. The frequency of mitoses was higher than in the normal ileum. The degree of acute and chronic inflammation was low and decreasing or stable. Dysplasia was never seen. Type B response (5 patients) comprised progressive, finally severe atrophy accompanied by increasing degree of acute inflammation. The number of mitoses was higher than in type A response. In two patients the number of goblet cells was moderately/severely decreased and epithelial atypia or low grade dysplasia occurred repeatedly. The response was regarded as indeterminate in one patient. The determination of the types of mucosal adaptation may help in the planning of the follow-up of these patients.

Dietary factors play essential roles in gastric carcinogenesis. We recently found that dietary supplementation with NaHCO3 significantly increased the development of gastric cancer in a rat gastric stump model. Here, we analysed nontransformed gastric mucosa for expression of the cancer-related proteins cyclooxygenase-2 (COX-2) and ornithine decarboxylase (ODC), and we examined the relationship between expression levels of those proteins and mucosal proliferation. Research has shown that COX-2 is upregulated in gastric mucosal inflammation and is strongly associated with gastrointestinal cancer. ODC is the key enzyme in polyamine synthesis and a regulator of cell proliferation. We performed gastric resections on 48 Wistar rats to induce spontaneous gastric cancer; half of these animals were given a normal diet, and the other half received a diet supplemented with NaHCO3. Twenty-four unoperated rats served as a control group. The surgical procedure per se led to a significant rise in mucosal expression of COX-2 and an associated increase in cell proliferation. However, the COX-2 level in gastric mucosa was not further affected by dietary supplementation of carbonate. Interestingly, nontransformed gastric mucosa in the operated rats receiving a carbonate-supplemented diet showed a pronounced increase in ODC expression that was strongly correlated with a further enhanced cell proliferation. These results indicate that carbonate ions, which represent a major constituent of intestinal reflux into the stomach, increase the expression of ODC and thereby enhance cell proliferation in nontransformed mucosa, and consequently elevate the risk of gastric cancer. © 2007 Wiley-Liss, Inc.

Background & Aims: A 30-year-old woman, treated with buserelin, an analogue of gonadotropin-releasing hormone (GnRH) (also called luteinizing hormone-releasing hormone, LH-RH), developed chronic intestinal pseudo-obstruction (CIPO). The sudden onset of this disease in a previously healthy woman perplexed us. CIPO refers to a gastrointestinal disorder that can have a variety of causes, such as drugs, among others. Thus, we wanted to examine whether in this patient the development of CIPO is related to the treatment with buserelin. Methods: The patient was examined using esophagogastroduodenoscopy, esophageal, and antroduodenojejunal manometry, gastric emptying tests, and histologic analyses and immunohistochemistry on full-thickness biopsies including staining with anti-GnRH antibody. Plasma samples were examined by the standard serologic analyses and specifically for the occurrence of anti-GnRH antibodies by enzyme-linked immunosorbent assay methods. Results: CIPO was diagnosed based on symptoms (abdominal pain, vomiting, and constipation), and the results of the clinical examinations, such as signs of esophageal aperistalsis, delayed gastric emptying, and small intestinal bursts. Histologic examination revealed a decreased number of myenteric neurons as well as increased neuronal degeneration and an abnormal immune profile. There was a loss of GnRH-containing neurons. The patient had high plasma titers of anti-GnRH antibodies, which occurred on the occasions of the treatment with buserelin. Conclusions: Our findings suggest that the patient has developed CIPO due to buserelin-induced formation of anti-GnRH antibodies destroying GnRH-producing neurons of the myenteric plexus.

Background. Previous studies have demonstrated that anti-CD40L or anti-B7 requires the presence of CD4(+)CD25(+) regulatory T cells (Treg) to induce antigen specific hyporesponsiveness. Other tolerance strategies involving Treg have shown a dependency on interleukin (IL)-10. The objective of this study was to investigate the role of CD4(+)CD25(+) Treg and IL-10 when treating transplant recipients with cytotoxic T lymphocyte-associated antigen (CTLA)-4 immunoglobulin (Ig), anti-CD40L, and anti-lymphocyte function-associated antigen (LFA)-1. Methods. Recombinase activating gene-deficient (Rag1(-/-)) mice were transplanted with BALB/c hearts and adoptively transferred with IL-10(-/-) CD4(+) T cells, CD4(+)CD25(-) T cells or CD4(+)CD25(-)CD103(-) T cells and treated with costimulation blockade. Intragraft T cells from C57BL/6 recipients were analyzed for the expression of the Foxp3 protein after tolerance induction. Results. Mice reconstituted with IL-10(-/-) CD4(+) T cells, CD4(+)CD25(-) T cells or CD4(+)CD25(-) CD103(-) T cells and treated with costimulation blockade accepted allografts permanently. Analysis of cells from recipient mice adoptively transferred with CD4(+)CD25(-) T cells contained a population of CD4(low)CD25(+) T cells 100 days after transplantation. Costimulation blockade partially prevented the homeostatic proliferation of CD4(+)CD25(-)CD103(-) T cells in Rag-1(-/-) recipients. Accepted allografts contained an elevated number of CD4(+)Foxp3(+) T cells. Conclusions. These results indicate that T-cell derived IL-10 is not essential for induction of graft acceptance in mice treated with costimulation blockade, but that treatment limits T-cell expansion in the recipients. The results further indicate that tolerance is maintained by intragraft CD4(+)Foxp3(+) T cells. (Less)

There is a need for immunosuppressive protocols in islet transplantation that are neither nephrotoxic nor diabetogenic. We have examined blockade of the CD28-B7, CD40-CD40L and ICAM-LFA-1 pathways in a model of allogeneic islet transplantation in mice to determine the efficacy of this blockade in prolongation of graft survival. Histological evidences of inflammation and function were evaluated in grafts that had been functioning for 100 days. Treatment with a combination of all three drugs, or with CTLA4Ig and anti-CD40L, administered four times during the first six postoperative days, resulted in an excellent graft survival. All animals had a graft survival of >100 days (i.e. indefinitely). Mice treated with CTLA4Ig and anti-CD40L all showed well-preserved islets without signs of degeneration or destruction. There were no signs of rejection, as evidenced by the absence of infiltrating lymphocytes. This group had the least amount of rejection/inflammation changes according to ranking of all grafts. In conclusion, a short induction treatment with anti-CD40L and CTLA4Ig totally prevents rejection and preserves the allogeneic islets transplanted to mice. The addition of anti-LFA-1 did not confer any benefit.