Overexpression of co-stimulatory molecules in peripheral mononuclear cells of Helicobacter pylori-positive peptic ulcer patients: possible difference in host responsiveness compared with non-ulcer patients

Differences in peripheral blood lymphocyte phenotypes between Helicobacter pylori-positive children and adults with duodenal ulcer

The immunological mechanisms involved in the development of duodenal ulcer, especially in childhood, are unclear. Helicobacter pylori-positive children and adults, with and without duodenal ulcer, were therefore compared with respect to CD4(+) T-cells, and CD8(+) T-cells, B-cells and B1a-cells, as well as cell activation (CD4(+)/HLA-DR(+) and CD8(+)/HLA-DR(+)) and co-stimulatory (CD4(+)/CD28(+) and CD8(+)/CD28(+)) markers, in peripheral blood. Children with and without duodenal ulcer differed significantly. In particular, there was a phenotypic change in CD8(+) T-cells from children with ulcer that involved a 200% increase in the number of CD8(+)/HLA-DR(+) cells/mm(3) and a decrease of 34.2% in the number of CD8(+)/CD28(+) cells/mm(3). This phenotype of chronically activated memory CD8(+) T-cells, which has also been observed in patients with AIDS and tuberculosis, is associated with disease severity and progression. A lower frequency of B1a-cells was also observed in the group of children with ulcer. Conversely, no difference between infected adults with and without ulcer was observed, but the percentage of CD4(+)/HLA-DR(+) cells was lower in adults with ulcer, suggesting that a down-regulated immune response may play a role in the development of duodenal ulcer in adults. Gastric inflammation correlated positively with CD4(+) and chronically activated CD4(+) T-cells in children and adults without duodenal ulcer, respectively. These results suggest that there are differences in the immunophenotyping profile between H. pylori-positive children and adults with duodenal ulcer, indicating the possibility of distinct immune mechanisms in the development of the disease according to age.

Soluble adhesion molecules ICAM-1, VCAM-1, P-selectin in children with Helicobacter pylori infection

AIM: To assess the sICAM-1, sVCAM-1, and sP-selectin levels in children with Helicobacter pylori (H pylori) infection and to evaluate their significance for the morphological changes found in gastric mucosa.

METHODS: The study included 106 children: 59 children (55.7%) with chronic gastritis and positive IgG against H pylori, 29 children (27.3%) after previous H pylori infection without the bacterium colonization but with positive IgG against H pylori, and 18 children (17%) with functional disorders of the gastrointestinal system but with normal IgG against H pylori. Endoscopic and histopathological evaluation of gastric mucosa was performed based on the Sydney System classification. The evaluation of sP-selectin, sICAM-1, sVCAM-1 levels in the sera of children was carried out using ELISA test.

RESULTS: The assessment of gastritis activity degrees indicated statistically significant values in the antrum and corpus (P<0.001) of children examined. Serum sVCAM-1 levels were higher in group with gastritis due to H pylori infection than in group without infection and differed statistically (P<0.05). Serum sVCAM-1 levels proved to be the highest among other adhesive molecules in infected children and decreased after eradication of H pylori. Serum sICAM-1 levels were similar in all examined groups. Serum sP-selectin levels were similar in children with and without H pylori infection.

CONCLUSION: Assessment of adhesive molecules (sP-selectin, sICAM-1, sVCAM-1) in the sera of children with active H pylori infection can show the participation of sVCAM-1 in the pathogenesis of gastric mucosal inflammation. sP-selectin and sICAM-1 concentrations in the sera of children with H pylori infection after eradication cannot reveal any significant differences as compared to healthy children.

Phenotypic study of peripheral blood lymphocytes and humoral immune response in Helicobacter pylori infection according to age

There are differences between children and adults in certain aspects of the Helicobacter pylori (HP) infection, among them the lower titre of IgG antibodies anti-HP in the former group. Thus, we investigated by means of flow cytometry CD4+/CD3+ (CD4+T), CD8+/CD3+ (CD8+T) and CD19+/CD3- (B) cells, activation/co-stimulatory markers (CD4+/HLA-DR+, CD4+/CD28+, CD8+/HLA-DR+ and CD8+/CD28+) and by means of ELISA IgG anti-HP antibodies in the peripheral blood from HP-positive and -negative children and adults. An increased CD4+/CD28+ and CD8+/CD28+ percentage and number of CD4+/CD3+ cells were seen in infected adults. Conversely, no difference was observed between infected and noninfected children, but when they were stratified by age, an increased CD4+/CD28+ cell percentage was seen in the HP-positive group older than 10 years. The mean level of IgG anti-HP was lower in younger infected children, increased with age and correlated with CD4+ cells. Our data suggest that the immune response to HP infection vary according to the age. Low percentage of activated CD4+ cell may contribute to the lower level of serum IgG anti-HP observed in younger infected children. In addition, the CD4+ cell participation during the infection seems to begin after 10 years old, when the immune response becomes similar to that seen in adults.

Correlation between CD4, CD8 cell infiltration in gastric mucosa, Helicobacter pylori infection and symptoms in patients with chronic gastritis

AIM: To evaluate the correlation between CD4, CD8 cell infiltration in gastric mucosa, Helicobacter pylori (H pylori) infection and symptoms or the assemblage of symptoms in cases with chronic gastritis.

METHODS: Biopsy samples at the gastric antrum were obtained from 62 patients with chronic gastritis. CD4 and CD8 cell infiltration was evaluated by immunohistochemical assays on frozen sections of the biopsy samples. Fifteen symptoms referring to digestion-related activity and non-digestion related activity were observed. The correlation between lymphocyte infiltration and each symptom or symptom assemblage was analyzed by logistic regression and K-mean cluster methods.

RESULTS: CD4 cell infiltrations in gastric mucosa were much more in patients with H pylori infection, while CD8 cell infiltrations were similar in patients with or without H pylori infection. Logistic regression analysis showed that the symptoms including heavy feeling in head or body (t = 2.563), and thirst (t = 2.478) were significantly related with CD4 cell infiltration in gastric mucosa (P<0.05), and cool limbs with aversion to cold were related with CD8 cell infiltration (t = 2.872, P<0.05). Further analysis showed that non-digestive related symptom assemblage could increase the predicted percentage of CD4 and CD8 cell infiltration in gastric mucosa, including lower CD4 infiltration by 12.5%, higher CD8 infiltration by 33.3%, and also non-H pylori infection by 23.6%. K-means cluster analysis of all symptoms and CD4 and CD8 cell infiltration in gastric mucosa showed a similar tendency to increase the predicted percentage of CD4, CD8 cell infiltration and H pylori infection.

CONCLUSION: Based on correlation between the gastric mucosa lymphocyte infiltration, H pylori infection and clinical symptoms, symptoms or symptomatic assemblages play an important role in making further classification of chronic gastritis, which might help find a more specific therapy for chronic gastritis.

Increased Frequency of Antral CD4+ T and CD19+ B Cells in Patients with Helicobacter pylori-Related Peptic Ulcer Disease

Only a fraction of Helicobacter pylori (HP)-infected individuals develop clinical disease. Recent research indicates that immunological mechanisms may be important for understanding the pathophysiology of HP infection. Differences in the individual cellular immune response may reflect the clinical diversity. The aim of the present study was to investigate the cellular immune response against HP in three clinically well-defined patient groups: HP-positive peptic ulcer, HP-positive and HP-negative gastritis. Biopsies from gastric mucosa were processed for analysis by flow cytometry and histology. The number of T lymphocytes (CD3+) was significantly higher in HP-positive peptic ulcer (13.8%) than in HP-positive nonulcer gastritis (6.3%). A nonsignificant increase for B lymphocytes (CD19+) was noted as well. Furthermore, a significant difference was seen in mucosal CD4/CD8 ratio between HP ulcer (2.4) and nonulcer HP gastritis (1.0) patients. Thus, B cells (CD19+) and T-helper cells (CD4+) were dominant in gastric mucosa from peptic ulcer patients, and cytotoxic T cells (CD8+) were relatively dominant in gastric mucosa from nonulcer patients. In conclusion, distinct differences in the T-cell subset distribution of mucosal lymphocytes were detected in patients with HP infection, strongly correlated with the presence or absence of peptic ulcer.

L-forms of H. pylori

AIM: To study the occurrence of L-forms of H. pylori infection in patients with peptic ulcers and its association with possible changes of cellular immune function in the patients.

METHODS: Endoscopic biopsy specimens of gastric antrum and gastric corpus were taken from 228 patients with peptic ulcers and inoculated into Skirrow selective medium for H. pylori vegetative forms and special medium for H. pylori L-forms, followed by bacterial isolation and identification. And peripheral venous blood of the patients was taken to detect the percentage of CD3⁺, CD4⁺ and CD8⁺ with biotin-streptavidin (BSA) and the level of IL-2, IL-6 and IL-8 with ELISA.

RESULTS: (1) The detection rates of H. pylori L-forms and vegetative forms in the patients were 50.88% (116/228) and 64.91% (148/228) respectively, and the co-infection rate of H. pylori L-forms and vegetative forms was 78.38% (116/148). To be more exact, the detection rates of H. pylori L-forms in male and female patients were 57.04% (77/135) and 41.94% (39/93) respectively, and statistics found significant difference between them (P < 0.05). Furthermore, the detection rates of H. pylori L-forms in patients aged 14 years-, 30 years-, 40 years- and 50 years- were 31.91% (15/47), 42.86% (24/56), 56.94% (41/72) and 67.92% (36/53) respectively, and there was significant difference between them (P < 0.01). (2) The percentages of CD3⁺, CD4⁺, CD8⁺, the ratio of CD4⁺/CD8⁺, and the level of IL-2, IL-6, IL-8 in H. pylori-positive patients were (52.59 ± 5.44)%, (35.51 ± 5.74)%, (27.77 ± 8.64)%, (1.56 ± 0.51), (2.66 ± 0.47) mg/L, (108.62 ± 5.85) ng/L and (115.79 ± 7.18) ng/L respectively, compared with those in H. pylori-negative patients, the percentages of CD3⁺, CD4⁺ and the ratio of CD4⁺/CD8⁺ decreased, but the level of IL-2, IL-6 increased, and the difference was significant (P < 0.001-P < 0.01). Moreover, the percentages of CD3⁺, CD4⁺, CD8⁺, the ratio of CD4⁺/CD8⁺, and the level of IL-2, IL-6, IL-8 in the patients with mixed infection of both H. pylori L-forms and vegetative forms were (51.69±5.28)%, (34.75 ± 5.89)%, (27.15 ± 7.45)%, (1.48 ± 0.47), (2.16 ± 0.38) mg/L, (119.45 ± 5.44) ng/L and (123.64 ± 6.24) ng/L respectively, compared with those in patients with simple infection of H. pylori vegetative forms, the percentage of CD4⁺, the ratio of CD4⁺/CD8 ⁺ and the level of IL-2 increased, but the level of IL-6 and IL-8 decreased, statistical difference was found between them (P < 0.001-P < 0.05).

CONCLUSION: L-forms variation often occurs in patients with peptic ulcers who are infected by H. pylori, which is commonly found in male patients and related to ages. The L-forms variation of H. pylori can be an important factor causing disorder of cellular immune function in the patients with peptic ulcers who are infected by H. pylori.

Novel risk factors for peripheral arterial disease in young women

PURPOSE

To investigate traditional and novel risk factors (homocysteine and C-reactive protein levels, and exposure to infections) for peripheral arterial disease in young women.

SUBJECTS AND METHODS

In a multicenter, population-based, case-control study, 212 young women (mean [+/- SD] age, 48.2 +/- 7.0 years) with peripheral arterial disease and 475 healthy control women (mean age, 45.5 +/- 8.1 years) completed a standardized questionnaire and provided blood samples. Peripheral arterial disease was angiographically confirmed if a stenotic lesion (more than 50% reduction of the lumen) was present in at least one major peripheral artery. Hyperhomocysteinemia was defined as a nonfasting plasma homocysteine level exceeding the 90th percentile of the control group. History of infectious diseases was determined by questionnaire.

RESULTS

Elevated C-reactive protein levels were associated with an increased likelihood of peripheral arterial disease (odds ratio [OR] = 3.9; 95% confidence interval [CI]: 1.8 to 8.5 for women in the third quartile; OR = 3.1; 95% CI: 1.4 to 6.8 for women in the fourth quartile; both comparisons with women in the first quartile). Hyperhomocysteinemia was not associated with a significantly increased risk of peripheral arterial disease (OR = 1.6; 95% CI: 0.9 to 3.0). A history of chickenpox, shingles, mumps, pneumonia, chronic bronchitis, peptic ulcer, or periodontitis was independently related to peripheral arterial disease, with adjusted odds ratios varying from 1.7 (95% CI: 1.0 to 3.1) for mumps to 3.4 (95% CI: 1.5 to 7.7) for peptic ulcer. The risk of peripheral arterial disease increased with the number of these infections; exposure to five or more infections increased the odds 3.7-fold (95% CI: 1.7 to 8.2). This association was not affected by the level of C-reactive protein.

CONCLUSION

Our results do not support a strong relation between homocysteine and peripheral arterial disease in young women. However, an elevated C-reactive protein level and several types of symptomatic infection were associated with peripheral arterial disease.

cag+ Helicobacter pylori induces homotypic aggregation of macrophage-like cells by up-regulation and recruitment of intracellular adhesion molecule 1 to the cell surface

Infection with cag+ but not cag-negative Helicobacter pylori leads to the formation of large homotypic aggregates of macrophage-like cells. Intracellular adhesion molecule 1 is up-regulated and recruited to the cell surface of infected cells and mediates the aggregation via lymphocyte function-associated molecule 1. This signaling may regulate cell-cell interactions and inflammatory responses.