Significant increase in antigastric autoantibodies in a long-term follow-up study of H. pylori gastritis

In 30% of H. pylori-infected patients a certain type of antigastric autoantibodies, reacting against canalicular structures within human parietal cells, is detectable. Furthermore, it has been shown that these autoantibodies are correlated with atrophy of the mucosa in the corpus. The aim of this study was to analyse the prevalence of these anticanalicular autoantibodies (ACAB) and their significance for development of gastric mucosa atrophy in a 12-year follow-up period. Gastric biopsy specimens from 62 persons in Saaremaa Island, Estonia, were collected in 1997 and assessed independently by two pathologists in accordance with the updated Sydney system. The sera of these persons were immunohistochemically screened for ACAB and for classic parietal cell antibodies (PCA). In addition, for 37 of the 62 persons, gastric biopsies and sera collected 12 years earlier (1985) were investigated in an analogous manner. ACAB increased significantly, from 8 out of 37 in 1985 to 17 out of 37 in 1997 (P=0.004; McNemar test). In 1997 a significant correlation existed between the presence of ACAB and corpus mucosa atrophy (19 out of 30 versus 10 out of 32 without atrophy; P=0.01; odds ratio (OR)=3.8, 95% CI 1.4–10.6). However, no correlation was found between ACAB and development of atrophy in the period from 1985 to 1997. All 37 persons were PCA negative in 1985, whereas in 1997, 2 turned out to be PCA positive. ACAB increased significantly with duration of H. pylori gastritis. The correlation between ACAB and presence of gastric corpus atrophy was confirmed. However, it is possible that ACAB are the consequence of and not a causative factor in gastric mucosa atrophy, insofar as the association of ACAB with progression of corpus atrophy was not significant. Received: 20 October 1999 / Accepted: 13 January 2000     

Eradication of Helicobacter pylori heals atrophic corpus gastritis caused by long-term treatment with omeprazole

 Long-term treatment with proton pump inhibitors in patients with Helicobacter pylori gastritis can lead to atrophic changes in the corpus mucosa. What is still unclear, however, is whether this atrophy can regress in response to Helicobacter pylori eradication. We report on a male patient with Helicobacter pylori gastritis receiving long-term treatment (4 years) with omeprazole for gastro-oesophageal reflux disease, who developed autoaggressive gastritis with progressive atrophy, hypochlorhydria, hypergastrinaemia and nodular ECL-cell hyperplasia. To determine whether these changes might be induced to regress, Helicobacter pylori eradication therapy was administered. Ten months after Helicobacter pylori eradication autoaggressive lymphocytic infiltrates were no longer detectable, and the glands in the corpus mucosa had normalised despite continued treatment with omeprazole – a finding that was confirmed at two further follow-up surveys performed at 6-month intervals. This case report shows that atrophy of the corpus mucosa developing under long-term treatment with a proton pump inhibitor can be cured by eradicating Helicobacter pylori. Received: 21 April 1998 / Accepted: 10 August 1998     

Evaluation of the applicability of the gastric carcinoma risk index for intestinal type cancer in Japanese patients infected with Helicobacter pylori

The gastric carcinoma risk index is a histological criteria to Helicobacter pylori-infected patients with a high risk of gastric cancer. The aim of this study was to examine the applicability of this index for the intestinal-type gastric cancer in Japanese patients with H. pylori infection. In 55 patients with early intestinal-type gastric cancer and 69 control subjects, we calculated the gastric cancer risk index score by evaluating the grade of mononuclear cell (MNC) and polymorphonuclear cell (PMN) infiltration and the presence of intestinal metaplasia. The gastric cancer index score was significantly higher in patients with gastric cancer (P<0.01). The presence of intestinal metaplasia was significantly more frequent in cancer patients than in controls, while infiltration of MNCs or PMNs in the corpus was not different in the two groups. Within the gastric cancer risk index, the presence of intestinal metaplasia was the only criteria associated with the development of intestinal-type gastric cancer in Japan. The gastric cancer risk index may not be applicable to identify H. pylori-positive patients at high risk of developing intestinal-type gastric cancer in Japan. Received: 6 October 1999 / Accepted: 22 December 1999     

Helicobacter pylori infection produces reversible glycosylation changes to gastric mucins

 The protective ability of gastric mucins may depend largely on their oligosaccharide chains. We evaluated the effects of H. pylori infection on the glycosylation of gastric mucins. Gastric biopsy specimens from 20 H. pylori-infected patients before and after cure of the H. pylori infection and 8 normal uninfected volunteers were examined by immunostaining for simple mucin-type glycoproteins and blood-group-related antigens bearing type 1 chain backbone. The immunoreactivity in different gastric compartments was evaluated. Simple mucin-type glycoproteins and blood-group-related antigens were expressed in surface mucous cells. Simple mucin-type glycoproteins showed antrum-predominant expression in normal volunteers and were found in significantly fewer surface mucous cells in infected patients than in normal volunteers; their expression was restored after eradication of H. pylori. Sialyl Lewis^a and Lewis^b were expressed in fewer surface mucous cells after than before eradication. The patterns of glycosylation of gastric mucins vary in different gastric compartments and are reversibly altered by H. pylori infection. These alterations may affect the protective functions of gastric mucins. Received: 23 April 1998 / Accepted: 2 July 1998     

Helicobacter pylori antigen in the glomeruli of patients with membranous nephropathy

 Renal biopsy specimens from patients with membranous nephropathy (MN) were studied using immunohistochemical labelling to clarify the aetiological significance of Helicobacter pylori antigen in this disease. Sixteen specimens were examined, from 7 male and 9 female MN patients. Renal specimens from patients with diabetic nephropathy and IgA nephropathy, and from autopsied patients without renal diseases were obtained as controls. Immunohistochemical labelling was performed using one polyclonal antibody and three monoclonal antibodies against H. pylori. Specimens from 11 of the MN patients revealed granular deposits along the glomerular capillary walls, which reacted positively with polyclonal antibody after trypsin pretreatment. None of the control specimens revealed positive labelling. The MN specimens showed no positive reaction with the primary antibody, which had been treated for immunoabsorption testing using sonicated H. pylori.We also determined H. pylori status in these MN patients histologically and/or serologically. Of the 11 patients whose glomeruli were positive for anti-H. pylori antibody, 7 were suitable for analysis, and all were regarded as positive for H. pylori infection. These results suggest that the presence of a specific antigen in the glomeruli of patients with MN and H. pylori infection may be involved in the pathogenesis of MN. Received: 18 October 1996 / Accepted: 3 March 1997     

Virulence factors of Spanish Helicobacter pylori isolates and correlation with gastritis or ulcer production

Objective: To study the cagA , vacA and iceA status of Helicobacter pylori clinical isolates obtained from adult patients suffering from peptic ulcer or gastritis in order to find if these virulence factors are useful in determining a strain to be a gastritis or ulcer producer.
Methods: One hundred and five H. pylori strains from patients with gastritis and ulcer were studied. Culture and identification was done by standard methodology. cagA, vacA and iceA detection was performed by PCRs previously described. Results were visualized by agarose gel electrophoresis.
Results: Amplified fragments of 297 bp ( cagA ), 259 bp ( vacA s1), 286 bp ( vacA s2) and 975 bp ( iceA ) were detected. cagA was detected in 83.3% and 91.3% of gastritis and ulcer strains respectively (p>0.05). s1 was detected in 57.1% of gastritis strains and 62.3% of ulcer strains (p>0.05). cagA was strongly related with the s1 allele. iceA was more prevalent in strains from gastritis (82.4% versus 66.7%). The combination of cagA, vacA and iceA was not correlated with the production of peptic ulcer disease.
Conclusions: These data suggest that the combination of cagA, vacA and iceA cannot be used to predict severe gastric disease in Spanish H. pylori clinical isolates.     

Apoptosis in human colorectal tumours: ultrastructure and quantitative studies on tissue localization and association with bak expression

 Apoptotic cell death in human tumours has been demonstrated by electron and light microscopy. In adenomas, fragmented and apoptotic nuclei and signs of phagocytosis have been observed close to the basement membrane. In carcinomas the characteristic structures were apoptotic bodies with small fragments of chromatin. DNA fragmentation was shown by in situ end-labelling. Quantitative assessment of apoptosis and proliferation revealed a high apoptotic index (AI) in all types of adenoma (tubular: 1.77±0.35%, tubulovillous: 2.38± 0.41%; villous: 3.3±0.39%) as well as loss of compartmentalization of proliferating and dying cells. In carcinomas a shift towards proliferation was evident, as shown by lower AIs than in adenomas (0.9±0.68% and 1.1±0.12% for moderately and poorly differentiated tumours), higher Ki67 indices (38.32±2.23% and 57± 3.89%, respectively) and higher mitosis (0.9±0.56% and 1.21±0.17%, respectively). However, apoptosis was observed in all tumours and is available as a target for therapeutic intervention. Expression of the apoptosis related proteins bcl-2 and bak also reflected loss of compartmentalization. While bcl-2 did not show a consistent relationship to AI in tumour specimens, bak was positively correlated with apoptosis in 4 of 8 adenomas and 4 of 7 carcinomas, suggesting a role for this protein in the induction of apoptosis in a subset of tumours. Received: 22 July 1997 / Accepted: 27 October 1997     

Diagnosis of chronic atrophic gastritis by morphometric image analysis. A new method to overcome the confounding effect of the inflammatory infiltrate

The risk of gastric cancer increases with the severity of gastric mucosal atrophy. Atrophy is a 'loss of properly specialized glands'. These glands may be substituted by metaplastic cells and by interstitial fibrosis, or displaced by an inflammatory infiltrate. Agreement among pathologists for the diagnosis of atrophy is poor (kappacoefficient < 0.4), probably because inflammatory infiltrate can confound the identification of gland loss. The aim of this study was to evaluate interstitial fibrosis by image analysis, and thereby overcoming the confounding effect of the inflammatory infiltrate. Gastric biopsies of 40 controls (20 children and 20 adults) and 111 patients with chronic atrophic gastritis were examined. Patients underwent another biopsy a year later. Gastric sections were examined by conventional histology (updated Sydney system) and image analysis to detect collagen and non-collagen fibres. There were no significant intra- or inter-operator differences in the evaluation by image analysis of fibre content in either controls or patients. In both controls and patients, the mean percentage of collagen fibres was lower in the gastric body (9%) than in the antrum (10%). In the antrum it was 14%, 17% and 20% in patients with mild, moderate and severe atrophy, respectively. A year later, histology showed that the grade of atrophy had decreased in 42%, probably due to the regression of inflammation, and increased in 10% of cases, but interstitial fibrosis (expressed as collagen fibre content) was practically unchanged. The use of image analysis of gastric biopsies appears to be a reliable method with which to measure interstitial fibrosis, even in the presence of an inflammatory infiltrate. This study highlights the difference between 'real gastric atrophy', where glands are replaced by collagen fibres, and 'apparent gastric atrophy', where glands are displaced by an inflammatory infiltrate.     

Immune response to Helicobacter pylori and its association with the dynamics of chronic gastritis in the antrum and corpus

The aim of the study was to establish possible factors which play a role in progression of gastritis to atrophic gastritis in long-term follow-up among the Estonian population, to assess the association between the host immune response and different Helicobacter pylori antigens and autoantigens in relation to the histological parameters of gastritis in the antrum and corpus. ELISA and immunoblot were used for detection of IgG to H. pylori acid glycine-extracted cell surface proteins, CagA protein, and H. pylori HSP60. Anticanalicular autoantibodies (ACAB) in the serum were evaluated according to Faller et al. (1996). Apoptosis was evaluated using the TUNEL method. Study subjects were 1958 persons from an unselected Estonian population, and 70 persons from a sample from Saaremaa Island, who had been investigated over a period of 18 years. Seropositivity for CagA was a sign of gastritis activity [OR=14.8 (4.5-50.3)] and atrophy [OR=7.0 (2.1-23.1)] and might predict development of atrophy, particularly in the corpus [OR=7.1 (1.8-27.7)]. The prevalence of ACAB increased significantly with duration of H. pylori gastritis from 22% in 1985 to 46% in 1997 (p=0.004). Immune response to H. pylori HSP60 indicates chronic inflammation in the antrum (p=0.003). Apoptosis of gastric epithelial cells is largely dependent on grade of activity of gastritis, and, particularly in the antrum, on grade of H. pylori colonization (p=0.01; p=0.02), but is not associated with development of atrophy. Seropositivity for different H. pylori antigens (CagA, HSP 60) serves as a marker of different histological manifestations in the antrum and corpus mucosa.     

Mucosal humoral immune response to CagA shows a high prevalence in patients with gastric MALT-type lymphoma

In the pathogenesis of gastric mucosa-associated lymphoid tissue (MALT)-type lymphoma, CagA-positive Helicobacter pylori strains have been suspected of making a significant contribution. To investigate this hypothesis in more detail, the mucosal humoral immune response of 15 patients with gastric MALT-type lymphoma was examined in the tumor and in the tumor-free gastritis of the same patient. Mononuclear cells from different sites (antrum, corpus, lymphoma) were cultured. Culture supernatant and serum of the same patient were used for immunodetection of CagA. All patients displayed an immune response to CagA in the tissue-culture supernatants. Although the humoral immune response in the tumor was restricted to a very few H. pylori antigens, antibodies directed against CagA protein were found in most patients. The immune response to CagA in nearly all lymphoma patients – not only in the serum, but also in the mucosa, including the tumor site – support the hypothesis that CagA is involved in the pathogenesis of gastric MALT-type lymphoma. Received: 16 April 1999 / Accepted: 30 August 1999     

Increased expression of interleukin-6 gene in gastritis and gastric cancer

Helicobacter pylori (H. pylori) induces an intense inflammatory response, mediated by proinflammatory cytokines, including interleukin (IL)-6 and its membrane receptor (IL-6R), which activates important signaling pathways in the development of gastric disease and cancer. We investigated the gene and protein expression of IL-6 and IL-6R and the influence of polymorphisms rs1800795, rs1800796, and rs1800797 on its gene expression together with H. pylori infection. Furthermore, an in-silico analysis was performed to support our results. Gastric biopsies were obtained from patients with gastric symptoms and patients with gastric cancer (GC) and were divided into groups (Control, Gastritis, and Cancer). H. pylori was detected by PCR. Real-time-qPCR was employed to determine gene expression, and western blot assay was used to analyze protein expression levels. PCR-RFLP was used to characterize IL-6 polymorphisms. Bioinformatics analyses were performed using the Gene Expression Omnibus (GEO) database and GEO2R to screen out differentially expressed genes (DEGs). H. pylori was detected in 43.3% of the samples. Statistically significant differences were found for IL-6 (P=0.0001) and IL-6R (P=0.0005) genes among the three groups, regardless of the presence of H. pylori. Among patients with H. pylori infection, the IL-6 and IL-6R gene and protein expressions were significantly increased, highlighting IL-6 gene overexpression in patients with GC. No statistically significant differences were found for the rs1800795, rs1800796, and rs1800797 polymorphisms compared to IL-6 gene expression. The results indicated that the IL-6 polymorphisms do not influence its expression, but IL-6 and IL-6R expression seems to be altered by the presence of H. pylori.     

Apoptosis of cytotoxic T-cells in histiocytic necrotizing lymphadenitis

 Cell death is necrotic or apoptotic. In histiocytic necrotizing lymphadenitis (HNL), apoptosis is the main form of cell death, resulting in the creation of nuclear debris that is one of the characteristic features of HNL. To investigate the cell type of apoptotic cells, 12 cases of HNL were analyzed using the immunohistochemical staining for TIA-1, a cytotoxic granule of either cytotoxic T or NK cells. One quarter to over half of all apoptotic cells were positive for TIA-1, and some of the nuclear debris was also positive. The necrotic lesions of HNL were found to consist of nuclear debris, apoptotic cells, histiocytes and lymphocytes. The lymphocytes were mainly CD8-positive T-cells or CD4-positive cells, while B- and NK cells were only rarely observed. The number of TIA-1-positive lymphocytes was more closely related to the number of CD8-positive cells than to the number of CD4 cells. In double staining, the TIA-1 positive lymphocytes were mainly CD8 positive, but rarely CD4 positive. In HNL, then, CD8-positive cytotoxic T-cells are likely to undergo apoptosis. Received: 4 November 1997 / Accepted: 9 March 1998     

The number of Helicobacter pylori CagA EPIYA C tyrosine phosphorylation motifs influences the pattern of gastritis and the development of gastric carcinoma

Ferreira R M, Machado J C, Leite M, Carneiro F & Figueiredo C
(2012) Histopathology  60, 992–998 The number of Helicobacter pylori CagA EPIYA C tyrosine phosphorylation motifs influences the pattern of gastritis and the development of gastric carcinoma Aims: To characterize the variation in virulence of Helicobacter pylori associated with CagA Glu‐Pro‐Ile‐Tyr‐Ala (EPIYA) motifs, and to explore its relationship with the histopathological features of chronic gastritis and with the development of gastric carcinoma. Methods and results: A total of 169 H. pylori‐infected patients with chronic gastritis and gastric carcinoma were studied. The presence of cagA and the number and type of EPIYA motifs were determined by polymerase chain reaction. Infection with strains harbouring two or more CagA EPIYA C motifs was associated with the presence of surface epithelial damage, and with atrophic gastritis and gastric carcinoma. The magnitude of risk for atrophic gastritis and gastric carcinoma increased with increasing number of EPIYA C motifs: strains with one EPIYA C motif conferred a risk (odds ratio [OR]) of 7.3 [95% confidence interval (CI) 2.1–25] for atrophic gastritis, whereas strains with two or more EPIYA C motifs conferred a risk (OR) of 12 (95% CI 2.5–58); strains with one EPIYA C motif conferred a risk (OR) of 17 (95% CI 5.4–55) for gastric carcinoma, whereas strains with two or more EPIYA C motifs conferred a risk (OR) of 51 (95% CI 13–198). Conclusions: Characterization of the number of H. pylori EPIYA C motifs is important in better defining gastric carcinoma risk.     

Immunological characterization of heterochromatin protein p25β autoantibodies and relationship with centromere autoantibodies and pulmonary fibrosis in systemic scleroderma

 Anticentromere antibodies (ACA) are immunological markers for the subset of systemic scleroderma with the symptoms calcinosis cutis, Raynaud’s phenomenon, esophageal dysfunction, sclerodactyly, and telangiectasia (CREST). In western blotting, some ACA-positive sera also recognize a doublet of 23 kDa (p23) and 25 kDa (p25) in addition to centromere protein antigens A (17 kDa), B (80 kDa), and C (140 kDa). Two forms of p25 have been shown to be human homologues of Drosophila heterochromatin-associated protein HP1. One form of p25 (p25β) which was recently cloned in this laboratory was used to evaluate anti-p25β antibody response in scleroderma sera. Of 318 scleroderma sera 42 had ACA (13.2%), and 16 of the 42 sera (38%) had anti-p25β antibodies. On the other hand, 5 of 276 ACA-negative sera (1.8%) showed anti-p25β antibody response, demonstrating that anti-p25β antibody is significantly associated with the ACA response (P<10^–8). Clinically the anti-p25β response was significantly associated with the CREST syndrome. Fourteen (36.8%) of 38 CREST patients compared to seven (2.5%) of 280 patients with other forms of scleroderma were anti-p25β antibody positive (P<10^–8). The 14 CREST patients with anti-p25β antibodies had significantly more interstitial lung disease than those without anti-p25β antibodies (P<0.003). There was also a tendency to increased liver involvement. Two dominant autoepitopes in p25β were determined by western blotting using p25β recombinant fragments. In immunofluorescence C-terminal specific antibodies showed staining of heterochromatin, but N-terminal specific antibodies showed no staining. Interestingly, the majority of sera reacted preferentially with one or the other of the two dominant autoepitopes. Received: 6 March 1997 / Accepted: 21 July 1997     

Thymidine phosphorylase expression results in a decrease in apoptosis and increase in intratumoral microvessel density in human gastric carcinomas

Thymidine phosphorylase (dThdPase) / platelet- derived endothelial cell growth factor (PD-ECGF) is expressed at higher levels in a variety of human carcinomas than in adjacent normal tissue. The higher expression is associated with an increase in intratumoral microvessel density (IMVD) and an unfavorable patient prognosis. This study examined the role of dThdPase in apoptosis, IMVD and p53 expression in human gastric carcinomas. dThdPase expression was noted in 12 (35.3%) of 34 early carcinomas, and in 20 (55.6%) of 36 advanced carcinomas. At least 10 areas consisting of carcinoma cells with diffuse dThdPase expression from the 32 dThdPase-positive tumors (category I), and 10 areas without dThdPase expression from the 38 negative tumors (category II) were selected from each case. For early gastric carcinoma, the mean IMVD was 88.8±19.4 in category I and 61.4±17.3 in category II carcinomas, while for advanced gastric carcinoma, the mean IMVD was 98.8±21.0 in category I and 76.0±27.1 in category II carcinomas. The mean IMVD was significantly higher in category I than in category II tumors (P<0.05). The mean apoptotic index (AI: percentage of apoptotic cells) was 1.95±1.30 in category I, and 3.76±1.49 in category II carcinomas for early gastric carcinoma, and 1.51±0.98 in category I and 2.14±0.66 in category II carcinomas for advanced gastric carcinoma, the value of the mean AI being significantly (P<0.05) higher in dThdPase- negative tumors (category II) than in the positive tu-mors (category I), regardless of tumor stage or histological type. There was a significant inverse correlation (P<0.001) between AI and IMVD. These results indicate that dThdPase expression is associated with both an increase in intratumoral microvessels and a decrease in apoptosis in human gastric carcinomas. Received: 8 November 1999 / Accepted: 20 January 2000     

Apoptosis in the development of the temporomandibular joint

 Apoptosis has been shown to be involved in remodeling of organs during development, and derangement of the apoptotic process may result in temporomandibular joint (TMJ) dysfunction or congenital malformation. To investigate the relationship between the development of the TMJ and apoptosis, rat fetuses at 17.5–20.5 days of gestation (E17.5–20.5, vaginal plug=E0) and rats at postnatal days 1, 2, 3, 5, and 10 (P1, 2, 3, 5, and 10) were examined by light (LM) and transmission electron microscopy (TEM) and electrophoretic analysis of DNA fragmentation. At E17.5 and 18.5, a few layers of slender mesenchymal cells which eventually develop into the TMJ disk were observed, although TEM or electrophoresis did not reveal apoptotic cells at these stages. At E19.5 and 20.5, all structures of the TMJ except the lower joint cavity could be distinguished, but at these stages apoptotic cells were not observed. In P1 condyles, apoptotic cells were observed by TEM both at the subsurface of the condyle and in the region at which the lateral pterygoid muscle attaches to the condyle. These apoptotic cells showed irregular chromatin condensation, convolution of the cell membrane, and fragmentation and disintegration of the cytoplasm. Electrophoretic analysis of the P1 condyle further confirmed DNA fragmentation. Apoptosis was not observed in all specimens at the P1 stage. It was confirmed in 8 out of 20 animals (10 out of 27 joints) by TEM and/or electrophoretic analysis. The shape of the upper portion of the condyle flattened progressively from E20.5 to P2. At this stage, the lower joint cavity was developing, as observed by LM. These findings suggest that the morphological changes of the mandibular condyle effected by apoptosis, together with development of the lower joint cavity, play important roles in the postnatal functional adaptation to external stimuli such as mechanical strain. Accepted: 11 June 1997     

Tumor Necrosis Factor Alpha and Apoptosis in Helicobacter pylori Related Progressive Gastric Damage: A Possible Mechanism of Immune System Involvement in Epithelial Turnover Regulation

Helicobacter pylori (HP) related inflammation is mediated by tumour necrosis factor alpha (TNFα), which “in vitro” increases epithelial apoptosis in response to infection. In the early stages of HP gastritis, a raised epithelial apoptosis occurs; this phenomenon becomes less evident with progression towards intestinal metaplasia. Aim of our study was to analyze “in vivo” mucosal TNFα in relation to epithelial apoptosis in the progression of HP related histological damage. Antral biopsies from 20 HP positive patients were retrospectively studied: 10 with and 10 without intestinal metaplasia (IM and CG group respectively); samples of 10 dyspeptics with normal HP negative stomach (N) were used as control. The following parameters were evaluated by immunohistochemistry: 85 kDa caspase-cleaved fragment (p85) of human poly (ADP-ribose) polymerase (PARP) labelling index (LI) as marker of apoptosis and TNFα LI in stromal cells as marker of inflammatory response. Both epithelial apoptosis and mucosal TNFα expression were higher in chronic active gastritis compared to intestinal metaplasia and controls (PARP and TNFα LI: CG>IM>N; ANOVA & Student-Neumann-Keuls; p<0.05 and p<0.01, respectively). Pearson' s coefficient showed a significant correlation between PARP and TNFα LI in IM and CG groups. Our data show that mucosal TNFα, similarly to what suggested “in vitro”, may be related “in vivo” to epithelial apoptosis thus suggesting a possible mechanism for immune system involvement in the control of gastric epithelial turnover.     

Association between virulence factors of helicobacter pylori and gastric mucosal interleukin-18 mRNA expression in dyspeptic patients

BackgroundHelicobacter pylori (Hp) infection is associated with gastritis and marked infiltration of the gastric mucosa by several cytokines secreting inflammatory cells that contribute to sustain and expand the local inflammation. Different clinical expressions of the infection may reflect distinctive patterns of cytokine expression. IL-1β, TNF-α, IL-17 and IL-23 have been reported to be involved in Hp-induced gastric mucosal inflammation, but the details and association to different patterns of inflammation and virulence factors remain unclear.MethodsTotal RNA was extracted from gastric biopsies of 51 Hp-infected patients and 44 Hp-negative patients. Mucosal IL-18 mRNA expression in gastric biopsies was determined by Real-Time PCR. Presence of virulence factors was evaluated using PCR.ResultsIL-18 mRNA expression was significantly increased in biopsies of Hp-infected patients compared to Hp-uninfected individuals. There was no association between virulence factors and IL-18 mRNA expression. Also severity of mononuclear infiltration was significantly higher in gastritis patients with vacA (m1)-positive compare patients with vacA (m2)-positive.ConclusionsIL-18 may play an important role in the inflammatory response and promote the chronic and persistent inflammatory changes in the stomach. This may ultimately influence the outcome of Hp-associated diseases that arise within the context of gastritis.     

Frequency and distribution of DNA fragmentation as a marker of cell death in chronic liver diseases

 To study the early stages of cell death in various types of chronic liver injury, liver biopsies from a total of 26 patients, including 7 with chronic hepatitis C(CHC), 4 with chronic hepatitis B(CHB), 7 with alcoholic liver disease (ALD), 4 with autoimmune or drug hepatitis(AI/DH), and 4 with primary biliary cirrhosis(PBC), were examined by an in situ nucleotidyl transferase assay (ISNTA), which detects DNA fragmentation. Positive nuclei in hepatocytes and sinusoidal lining cells were counted in all parenchymal areas, excluding triads and areas of fibrosis, using a computer with Sigmascan software. The number of positive hepatocytes/mm² was similar in the biopsies of patients with CHC, CHB, ALD and AI/DH, but significantly lower in PBC. The number of positive sinusoidal lining cells/mm² was significantly greater in biopsies with CHC compared to CHB, ALD, AI/DH and PBC. Double staining revealed that the ISNTA-positive sinusoidal lining cells were also CD68 positive, indicating that they were Kupffer cells. The frequency of ISNTA positivity did not correlate with serum AST or ALT levels, steatosis, cell swelling or cirrhosis. ISNTA-positive hepatocytes were more frequent than acidophilic bodies in every disease category. We conclude that apoptosis may be a common pathway of cell death in different liver diseases, that the high frequency of DNA fragmentation in Kupffer cells in CHC suggests that during chronic hepatitis C infection activated Kupffer cells may be subject to regulatory control by apoptosis and that ISNTA is more sensitive than acidophilic bodies in assessing the degree of cell injury in the liver. Received: 17 February 1997 / Accepted: 18 March 1997     

幽门螺杆菌感染对人牙龈组织细胞凋亡的影响

目的:观察正常牙龈组织中幽门螺杆菌(Hp)的感染情况及其对人牙龈组织细胞凋亡的影响。方法:采用聚合酶链式反应(PCR)检测30例健康牙龈组织中Hp感染情况,应用脱氧核糖核苷酸末端转移酶介导的原位缺口末端标记(TUNEL)法检测牙龈组织中的细胞凋亡指数,分析Hp对牙龈组织的毒性作用。结果:PCR检测的30名患者,Hp阳性率为40%。在TUNEL结果中,可见Hp阳性组有大量棕色凋亡细胞,部分细胞核固缩成团或核膜周围边集成环状。而正常对照组中阳性凋亡细胞较Hp感染组明显偏低,2组细胞凋亡指数差异有统计学意义。结论:Hp感染可能是引起牙龈组织细胞凋亡的因素之一。