Beta-2-microglobulin and Helicobacter pylori infection in uraemic dialysed patients

β2-microglobulin is overexpressed in buccal cells of elderly and correlated with expression of p16 and inflammatory genes

β2M (Beta 2 microglobulin) is a small protein that is found in all nucleated cells, previous finding showed that its levels increased in the serum of the elderly. Buccal cell samples are none invasive approach for assessing the expression of target genes. There was rationality to assess the expression of β2M in buccal cells of people of a different group of ages. Indeed, the expression of β2M increased significantly with fold change 3.40, 4.80, 6.60^**, 8.20^*** and 12.04^*** for the group of age 18–25 years, 26–35 years, 36–45 years, 46–55 years, and 56–70 years respectively. The same observation was seen with markers of biological aging (p16^INK4a) with fold change 3.19, 3.90, 4.80*, 8.50^*** and 12.40^*** for the group of age 18–25 years, 26–35 years, 36–45 years, 46–55 years, and 56–70 years respectively. As expected, there was an increase in the inflammatory genes (IL-1 β and IL-6) expression in the elderly. Moreover, there was a direct significant correlation (r = 90, p < 0.001) between β2M expression and age (years), and the same direct significant correlation between p16^INK4a expression and age (years) was also seen (r = 90, p < 0.001). In addition, a direct correlation between β2M and p16^INK4a was also seen (r = 0.8.3, p < 0.001), there was also direct correlation between β2M and IL-1 β and IL-6 with (r = 0.5, p < 0.001; r = 0.68, p < 0.001) respectively. This evidence showed that β2M increased in buccal cells of the elderly compared to younger, and thereby buccal cells can be exploited to assess biological aging by measuring β2M levels, however, large sample size and using another assessing method such as β2M protein levels should be performed to confirm the results.

Beta 2 microglobulin correlates with oxidative stress in elderly

Beta 2 microglobulin (Β2M) is expressed in all nucleated cells, it interplays with mediators to regulate and modulate cellular functions. Its role in aging associated disorders has been documented recently. Oxidative stress has been known to play a direct implication on these disorders. Therefore, there is a rationality to explore the function of Β2M in oxidative stress in elderly people. The aim of the study was to assess the Β2M levels in different group of age, and to study the correlation between Β2M and oxidative stress. Actually, the serum levels of Β2M increased significantly in old people comparing to youngers. In addition, there was a positive correlation between Β2M levels and the age of participants (p < 0.001). In addition, there was a positive correlation between Β2M levels and Malondialdehyde (MDA) (p < 0.001), which underscored the possible role of Β2M in oxidative stress. To confirm the previous result, the correlation between total antioxidant capacity (TAC) and Β2M was assessed. There was a negative correlation between them (p < 0.001). These results suggested a possible role of Β2M in oxidative stress status in elderly people; in addition, it suggested the ability of using Β2M as a novel biomarker for oxidative stress. However, further work should be conducted to explore the exact role of Β2M in oxidative stress, and to include large sample size to confirm the results before translating the findings to clinic.

The relationship between Helicobacter pylori and beta-2 microglobulin in humans

H. pylori is related to various gastrointestinal diseases. β₂ Microglobulin (β₂M) is an intrinsic element of major histocompatibility complex (MHC I). Serum β₂M level may increase in inflammatory states. The aim of current study is to evaluate the relationship between β₂M and H. pylori bearing CagA strains. Methods. H. pylori status was determined by histopathology of samples taken from stomach. CagA status and β₂M level were measured from blood samples of patients. Eradication therapy was administered to the patients with H. pylori infection. β₂ Microglobulin levels were measured before and after treatment. Results. 35 (29.2%) H. pylori(−) patients and 85 (70.8%) H. pylori (+) patients were included in the study. There were 52 (43.3%) patients with CagA negative and 33 (27.5%) patients with CagA positive H. pylori infection. The mean serum β₂M level was 1.83 mg/L in H. pylori (−) group, 1.76 mg/L in H. pylori (+) CagA (−) group, and 1.93 mg/L in H. pylori and CagA (+) group (P > 0.05). Serum β₂M levels (1.82 versus 1.64 mg/L P < 0.05) were decreased after eradication. Conclusion. H. pylori and CagA status did not affect β₂M level. Relationship between low grade systematic inflammation and H. pylori should be investigated to find out new predictors for diseases associated with inflammation.

Serum and tissue beta-2 microglobulin levels in patients with Helicobacter pylori infection

BACKGROUND AND AIM

Beta-2 microglobulin (beta2-m) is a minor plasma protein, secreted from the plasma membranes as a result of the continuous regeneration of membrane proteins in the cell surface of all nucleated cells. The relationship between Helicobacter pylori and beta2-m has not been adequately established in studies. In this study, we aimed to compare the levels of serum and tissue beta2-m in patients with and without H. pylori infection, and to examine the relationship between levels of serum and tissue beta2-m.

MATERIAL AND METHODS

About 30 patients with H. pylori gastritis and 22 healthy persons were enrolled in this study. Gastric biopsies were histologically analyzed and compared according to tissue and serum beta2-m levels.

RESULTS

Serum beta2-m levels were comparable in H. pylori and control groups. There was no significant link between tissue H. pylori grade and serum beta2-m levels. Subendothelial beta2-m was detected in 19 (63.3%) cases with H. pylori and none of the control group with immunohistochemical staining (P < 0.001). There was no correlation between serum and tissue levels of beta2-m.

CONCLUSION

beta2-m accumulates in the majority of gastric tissues of patients with active chronic gastritis who were H. pylori (+), whereas no accumulation was found in H. pylori (-) control subjects.

An increased number of follicles containing activated CD69+ helper T cells and proliferating CD71+ B cells are found in H. pylori-infected gastric mucosa

OBJECTIVE

An immune response occurring in Helicobacter pylori-infected gastric mucosa could have a direct implication for associated pathologies. In the present study we analyzed the expression of the immune activation, proliferation, and phenotype markers by immune cell subpopulations in H. pylori-infected and uninfected gastric samples.

METHODS

Antral gastric biopsies from both H. pylori-positive and -negative patients were processed by immunohistochemistry; gastric epithelial cells were isolated from biopsy tissue and analyzed by flow cytometry.

RESULTS

Ten of the 13 biopsies that contained follicles were H. pylori positive. Follicular CD69 was expressed mainly by CD4+ T cells and the central core of follicles showed double immunopositivity for the B-cell marker CD19 and transferrin receptor. Also detected was an increase in the percentage of epithelial cells from H. pylori-positive samples expressing HLA-DR and beta2 microglobulin, compared to negative samples (61 +/- 15% vs 9 +/- 9%, p = 0.003 and 93 +/- 7% vs 52 +/- 18%, p = 0.002, respectively), whereas no variation on class I HLA was detected.

CONCLUSIONS

These results suggest that chronic H. pylori infection could facilitate the persistence of follicles on which continuous follicular helper T-cell activation could lead to uncontrolled follicular B-cell proliferation. Furthermore, beta2 microglobulin expression by epithelial cells in a nonparallel way to class I HLA may indicate the possibility of nonclassical class I MHC expression on the basal surface of the epithelium.

Delayed gastric emptying and Helicobacter pylori infection in patients with chronic renal failure

Forty patients with chronic renal failure (CRF) were enrolled in this study. Twelve of the 40 patients had upper gastrointestinal symptoms or signs (GI Sx). Twenty of the 40 patients had been receiving regular haemodialysis (HD) for at least 1 year prior to the study. Radionuclide-labelled solid meals were used to calculate gastric emptying times (GETs). The carbon-14 urea breath test (14C4-UBT) was used to diagnose Helicobacter pylori (HP) infection. Among the 40 patients, 35 (88%) had an abnormal GET and 22 (55%) had a positive 14C-UBT for HP infection. There were no statistically significant differences in the incidence of abnormal GET among patients with HP infection and patients without HP infection. There were also no significant differences in the incidence of HP infection among patients with abnormal and normal GETs. In addition, the incidences of abnormal GET in patients with and without upper GI Sx were 83% and 89% respectively. The incidences of HP infection in patients with and without upper GI Sx were 58% and 54%, respectively. The incidences of abnormal GET in HD and non-HD patients were 95% and 80%, respectively. The incidences of HP infection in HD and non-HD patients were 45% and 65%, respectively. The differences in the incidences of abnormal GET and HP infection among HD and non-HD patients, as well as among patients with and without upper GI Sx, were not statistically significant.