[The effects of nuclear factor-kappa B p65 antisense oligonucleotides on expression of proinflammatory cytokines in lamina propria mononuclear cells from patients with ulcerative colitis]

To investigate if nuclear factor-kappa B (NF-kappa B) p65 antisense oligonucleotides might affect the expression of NF-kappa B p65 and cytokines in lamina propria mononuclear cells(LPMC) from patients with ulcerative colitis (UC). LPMC were isolated from intestinal mucosal biopsy specimens from 3 patients with UC, and cultured with or without NF-kappa B p65 antisense oligonucleotides (5'-GGAACAGTTCGTCCTATGG-3'), missense oligonucleotides (5'-GGAACAGTTCGTCTATGG-3') and dexamethasone. NF-kappa B p65 expression was determined by western blot analysis. The expression of cytokine mRNA was studied by reversal transcription-polymerase chain reaction (RT-PCR). The cytokine levels were measured by enzyme linked immunosorbent assay. The results showed that NF-kappa B p65 antisense oligonucleotides resulted in down-regulation of NF-kappa B p65 expression, blocked the expression of IL-1 beta mRNA and IL-8 mRNA, and strikingly reduced the production of IL-1 beta and IL-8, and these effects were greater than those of dexamethasone in cultured LPMC from patients with UC(P < 0.05). Therefore, the application of NF-kappa B p65 antisense oligonucleotides may serve as a novel molecular approach for the treatment of patients with UC.

[The early diagnosis and treatment of gastric mucosa-associated lymphoma]

OBJECTIVE

To determine the general markers for the diagnosis of gastric mucosa-associated lymphoid tissue (MALT) lymphoma and select optimal cases to be interfered in early stage.

METHODS

To investigate the changes of histology, Ki-67 expression, monoclonality of IgH gene rearrangement in gastric lymphoid hyperplasia (GLH) cases before and after Helicobacter pylori (Hp) eradication treatment. Histological changes were classified according to Isaacson's criteria of GLH; L26, UCHL-1, anti-Kappa, anti-Lambda and Ki-67 were applied for immunohistochemical staining; semi-nest PCR was used to detect IgH gene rearrangement.

RESULTS

Thirty-one cases of GLH with predominant chronic gastritis and gastric ulcer were studied. The ratio of male to female in the 31 cases was 1.8 and the mean course 6.8 years. Twenty-nine cases had Hp infection. Most of the cases belonged to histological grade II and III. Only 1 case had lambda light chain restriction and 10 cases had monoclonal IgH gene rearrangement. Expression of Ki-67 and monoclonal IgH gene rearrangement were significantly increased with the crescendo of lymphoid hyperplasia grading (P < 0.05). 28 cases were given antibiotics with eradication of Hp in 24 cases and 2 cases had to be given another course of treatment. These cases were followed-up on average for 4.6 months. 18 cases showed complete regression both histologically and endoscopically, 4 cases partial regression and 6 cases no change. Four cases with histological grade II, III had the decrease of expression of Ki-67 and reversed to polyclonal IgH gene rearrangement, while there was no change in 4 cases with histological grade IV.

CONCLUSIONS

General considerations of histology, expression of Ki-67 and combined clonality of IgH gene rearrangement help to screen cases which need intervention early and make a diagnosis of gastric MALT lymphoma in early stage. Monoclonal IgH gene rearrangement in cases with histological grade III or IV appears to carry more clinical significance.

An age-related increase in the number of CD8+ T cells carrying receptors for an immunodominant Epstein-Barr virus (EBV) epitope is counteracted by a decreased frequency of their antigen-specific responsiveness

The aim of this study was to provide a basis for investigating the effects of one very common environmental factor, Epstein-Barr virus (EBV), on age-related changes in the immune system. To this end, the frequency of CD8(+) T cells carrying receptors for an immunodominant EBV lytic epitope was assessed by direct staining with HLA-peptide tetrameric complexes in 19 very old (>87 years) and 12 young (20-40 years) EBV carriers. The frequency of EBV-tetramer-positive cells within the CD8(+) subset was significantly greater in the old compared to the young group (P=0.001). However, the frequency of EBV antigen-specific IFN-gamma producing T cells, as determined by ELISPOT, was significantly lower in the old (P=0.001). Therefore, the absolute number of functional EBV-specific T cells in the elderly and the young was probably similar. These data suggest CD8 clonal expansions in the elderly, resulting in an accumulation of dysfunctional EBV-specific cells which possibly fill the 'immunological space' and could lead to a shrinking of the T cell repertoire for other novel antigens. This may help to explain the increased incidence and case-fatality caused by viruses and intracellular pathogens in the elderly.

[Interleukin 18 expression in colon cancer and adenoma]

OBJECTIVE

To investigate the expression of interleukin 18 in mucosa of colon cancer and adenoma.

METHODS

Expression of interleukin 18 was measured with immunohistochemical staining.

RESULTS

The expression rates of IL-18 in colon cancer, adenoma and relative normal mucosa were 78.8%, 100% and 100%, respectively (P > 0.05). In the case of colon cancer, the higher the cancer was differentiated, the higher the IL-18 expression level was observed (P < 0.05). In the case of colon adenoma, no significant relation was noted between the grade of dysplasia and the expression of IL-18 (P > 0.05).

CONCLUSION

In colon adenoma, all mucosae express IL-18. But in colon cancer, IL-18 expression is decreased or absent, and the lower the cancer is differentiated, the lower will be the level of IL-18 expression in epithelium.

Pathways to a robust immune response in the elderly

Circumstantial evidence suggests that infectious disease is the major cause of morbidity and mortality in the elderly, and immune-system dysfunction may contribute to this finding. Because innate and humoral immunity seem to be relatively unaffected by aging and because the T-cell compartment shows marked age-associated alterations, this article focuses on the association between T cells and aging. Longitudinal studies suggest that immune parameters, which predominantly are related to T cells, can be clustered to yield an IRP that is predictive of mortality in the elderly. Determining the IRP also may be helpful in younger individuals, particularly those under chronic antigenic stress (eg, patients with cancer or chronic infections) who experience premature aging of the immune system. Some changes in T cells can be modeled in clonal cultures in vitro to discover new biomarkers of immune aging. These biomarkers, which need to be validated in vivo, could be used to refine IRP. Interventions to selectively target changes that are identified as part of IRP may improve the health and quality of life of the elderly, reduce healthcare costs, and avoid potential unwanted side effects of global intervention approaches, such as triggering or exacerbating autoimmunity and inflammation.

The abl/bcr gene product as a novel leukemia-specific antigen: peptides spanning the fusion region of abl/bcr can be recognized by both CD4+ and CD8+ T lymphocytes

Chronic myelogenous leukemia (CML) is characterized by a reciprocal translocation leading to the Philadelphia chromosome. Two fusion genes are created by this translocation: bcr/abl and abl/bcr. The fusion regions of both translocation products are unique and strictly limited to leukemia cells, giving rise to potential tumor-specific antigens. Although several studies on the immunogenicity of peptides spanning the bcr/abl fusion region have been reported, little is known about the corresponding reciprocal translocation product abl/bcr. Here we report that synthetic peptides representing the fusion region of the abl/bcr forms a1bb3 and a1bb4 can be specifically recognized by HLA-A2-restricted cytotoxic T lymphocytes from healthy donors. Furthermore, HLA-matched a1bb3-expressing CML cells can be recognized by a1bb3-specific HLA-A2-restricted T cells, indicating natural processing and presentation of abl/bcr protein by leukemia cells. Moreover, a 19-mer peptide encompassing this class I-binding sequence also elicited a1bb3-specific class II-restricted T-cell responses. Thus, both class I- and class II-restricted T-cell responses can be stimulated in healthy donors by abl/bcr peptides in vitro. Because abl/bcr is expressed in the majority of CML patients, it may represent a highly leukemia-specific antigen with potential use in immunotherapy.

Compromised interferon gamma (IFN-gamma) production in the elderly to both acute and latent viral antigen stimulation: contribution to the immune risk phenotype?

The elderly suffer from an increased incidence of infectious disease, accompanied by increased morbidity and mortality. Interferon-gamma plays an important role in defense against intracellular pathogens such as mycobacteria and viruses. A reduced capacity to produce this cytokine in the elderly, as demonstrated by our findings of significant decreases in IFN-gamma production in vitro on stimulation with bacterial products (LPS) or viral antigens (influenza vaccine), might therefore contribute to disease susceptibility. Moreover, accumulating data suggest that persistent infection with EBV and particularly CMV impacts upon the immune system in aging and may contribute to the immune risk phenotype (IRP), which predicts remaining longevity in the very elderly. Using tetramer technology and IFN-gamma ELISPOT assays, we found that the commonly-observed clonal expansions of CD8+ T-cells in the elderly were for the most part poorly-functional CMV- and EBV-specific cells, expressing little CD28. The resulting accumulation of dysfunctional cells may lead to a reduction of the repertoire of functional T-cells available for responses to novel antigens. Further longitudinal studies are needed to demonstrate whether cytokines such as IFN-g are also part of the IRP. Improving the definition of the IRP will help to understand and thus prevent or reverse age-associated immune dysfunction.

Differentiation between intestinal tuberculosis and Crohn's disease in endoscopic biopsy specimens by polymerase chain reaction

OBJECTIVES

It is difficult to differentiate intestinal tuberculosis from Crohn's disease because of similar clinical, pathological, radiological, and endoscopic findings. The purpose of this study was to investigate the value of polymerase chain reaction (PCR) assay in the differentiation intestinal tuberculosis from Crohn's disease, and compare the histopathological features of endoscopic biopsy of the two disorders.

METHODS

A total of 39 endoscopic biopsy specimens from patients with intestinal tuberculosis and 30 specimens from patients with Crohn's disease were subjected to pathological analysis retrospectively, Ziehl-Neelsen stain, and PCR assay.

RESULTS

Except for granuloma with caseation and confluence, which was the characteristic of intestinal tuberculosis, other pathological features of intestinal tuberculosis and Crohn's disease were very similar or were difficult to find in endoscopic biopsy specimens. The positivity rate by PCR in 39 intestinal tuberculosis specimens was 64.1% (25/39), but was zero by PCR in 30 Crohn's disease specimens. Moreover, in the tissues of intestinal tuberculosis with granulomas similar to those of Crohn's disease, there were 71.4% (10/14) positive by PCR, and there were 61.1% (11/18) positive in intestinal tuberculosis tissues without granulomas.

CONCLUSIONS

Biopsy is of limited diagnostic value in the differentiation intestinal tuberculosis from Crohn's disease, and PCR is valuable in the differentiation between intestinal tuberculosis and Crohn's disease.

Experimental and numerical studies of noise-induced coherent patterns in a subexcitable system

A subexcitable medium of Belousov-Zhabotinsky (BZ) reaction subjected to external Gaussian white noise is studied in experiments and numerical simulations. We observe that at an optimal level of noise the wave sources of excited traveling waves become synchronous, as though there exists a long distance spatial correlation. The synchronous behavior fades if the noise level becomes larger or smaller. Numerical simulations confirm the experimental findings, and point out that the best synchronous behavior takes place when the signal-to-noise ratio of waves becomes largest.

[Activation of nuclear factor-kappaB and its relationship with cytokine gene expression in colonic mucosa of ulcerative colitis patients]

OBJECTIVE

To investigate the activation of nuclear factor-kappaB (NF-kappaB) and its relationship with expression of cytokine mRNA in intestinal mucosal biopsy specimens from patients with ulcerative colitis (UC).

METHODS

31 cases with UC were included in the study. 17 cases received sulfasalazine (SASP) or SASP and glucocorticoid treatment. 14 cases did not receive any medication related with UC. Normal mucosa from 11 colon cancer cases served as control. Ten pieces of intestinal mucosal biopsy specimens were obtained from each patient. NF-kappaB DNA binding activity was evaluated with electrophoretic mobility shift assay (EMSA). Expression of cytokine mRNA were studied with reversal tanscription-polymerase chain reaction (RT-PCR).

RESULTS

(1) The expression of IL-1beta mRNA and IL-8 mRNA was increased significantly in patients with UC, as compared with that in the control specimens (P < 0.05) and had a significant positive correlation with NF-kappaB DNA binding activity (r = 0.8363, P < 0.05; r = 0.6024, P < 0.05, respectively). (2) Glucocorticoids and SASP strongly inhibited NF-kappaB activation and signficantly decreased the expression of IL-1beta mRNA and IL-8 mRNA.

CONCLUSIONS

NF-kappaB is a major and essential factor in regulating the expression of cytokine and plays a fundamental role in the pathogenesis of UC. SASP and glucocorticoids decrease cytokine expression via inhibition of NF-kappaB activation.

[Activation of nuclear factor-kappaB and effects of anti-inflammatory treatment thereon in intestinal mucosa of patients with ulcerative colitis]

OBJECTIVE

To investigate the activation and expression of nuclear factor-kappaB (NF-kappaB) and effects of anti-inflammatory treatment on NF-kappaB in the intestinal mucosa of patients with ulcerative colitis (UC).

METHODS

Ten pieces of colon mucosal biopsy specimens were obtained from 31 cases with UC, 17 of which received sulphasalazine (SASP) or SASP plus glucocorticoid and 14 of which received no medication. Samples of normal mucosa around the lesion taken from 11 patients with colon cancer were used as controls. NF-kappaB DNA binding activity was evaluated by electrophoretic mobility shift assay. NF-kappaB p65 expression was determined by Western blot analysis and immunohistochemical staining with a NF-kappaB p65 antibody. The type of cells containing activated NF-kappaBp65 was identified by double immunofluorescence confocal laser scanning microscopy.

RESULTS

The expression of NF-kappaB p65 and NF-kappaB DNA binding activity were significantly higher in patients with UC than in the control (P < 0.05), and were correlated with the degree of inflammation. The NF-kappaB expression was significantly stronger in the nuclei than in the cytoplasm in patients with UC without pharmacotherapy. The NF-kappaB expression in nuclei was significantly stronger in the group without pharmacotherapy than in the group with pharmacotherapy (P < 0.05). Only a few NF-kappaB p65 positive cells were seen in the controls. NF-kappaBp65 expression was found in all major subsets of mononuclear cells, including macrophages, B lymphocytes, T lymphocytes, and cryptal epithelial cells.

CONCLUSION

The increased activation of NF-kappaB and increased expression of NF-kappaB may be involved in the pathogenesis of UC. Glucocorticoids and SASP strongly inhibited NF-kappaB activation and expression. The inhibition of NF-kappaB activation may be a central part of the anti-inflammatory action of glucocorticoids and SASP, which might represent an important pharmacological mechanism in treatment of patients with UC. NF-kappaB will be an important target for cytokine-based therapy of UC.

[The effects of butyrates and non-steroidal anti-inflammatory agents on HT-29 colonic carcinoma cells]

OBJECTIVE

Adenocarcinoma cells HT-29 were used to investigate whether butyrates and non-steroidal anti-inflammatory agents (NSAIDs, aspirin and NS-398) would be effective adjuvants for inducing apoptosis and to probe its possible mechanisms.

METHODS

Prostaglandin E(2) (PGE(2)) isolated from HT-29 cell culture supernants was investigated with ELISA. Flow cytometry was used for estimating apoptosis. The morphology of apoptotic cells was investigated by means of electron microscopy.

RESULTS

Butyrates could stimulate the secretion of PGE(2). In contrast, NSAIDs inhibited it to a level below 30 ng/L. Both butyrates and NSAIDs could induce apoptosis. The effects showed the obvious tendency of time- and concentration-dependency (P < 0.05). Combination with two drugs could enhance the above effects.

CONCLUSIONS

Butyrates and NSAIDs could induce apoptosis individually. Combination with the two drugs could enhance the above effects by down-regulating cyclooxygenase-2 expression.

Basic biology and clinical impact of immunosenescence

Immunosenescence is an age-associated decline of immunity involving multiorgan changes. As the mean age of the population increases, an increase of diverse pathologies associated with immunosenescence has been observed in the developed countries. Age-related changes in the immune system contribute to the increased incidence and severity of infectious diseases and possibly cancer in the elderly. Moreover, in young individuals chronic activation of the immune system (as occurs in autoimmune diseases, cancer, HIV infection and other chronic infections) induces changes in the immune response that parallel those observed in elderly individuals. An interdisciplinary approach to immunosenescence including investigation of the molecular and cellular mechanisms and clinical aspects is being utilised by the EU program "Immunology and Ageing in Europe" (ImAginE, QLK6-CT-1999-02031), the second major international conference of which took place in Córdoba, Spain, 22-26th March, 2001). We briefly summarise some of the highlights of the meeting here, and bring together in this special issue a collection of peer-reviewed papers reflecting the broad approach to immunosenescence currently being applied.

[The growth inhibition of colorectal adenoma cells by sulindac and its mechanisms]

OBJECTIVE

This study was conducted to assess the growth inhibition of colorectal adenoma cells by sulindac and identify the possible mechanisms.

METHODS

The colorectal adenoma cells from human sporadic adenomatous polyps were cultured, and then treated with sulindac. The cell viability was examined by MTT colorimetric assay; the S-phase fraction and the percentage of apoptosis were measured by flow cytometry.

RESULTS

Following sulindac treatment at different concentrations for 24, 48 and 72 hours, reduction of the cell viability was time- and dose-dependent. After 48-hour-treatment, S-phase fraction was decreased and the percentage of apoptosis was increased; both indexes of all groups except 0.3 mmol/L group were different from those of controls (P < 0.05).

CONCLUSION

These data suggested that sulindac could inhibit the growth of the colorectal adenoma cells, and its mechanisms might be related to suppressing proliferation and inducing apoptosis.

[The primary culture methods of colorectal adenoma cells]

OBJECTIVE

To improve the primary cell culture methods of colorectal adenomas.

METHODS

The methods of the in vitro primary cell culture of colorectal adenomas, mainly the method for taking and preparing specimen, the methods of culture conditions and cells purification, were considered again and improved in this study.

RESULTS

Of the 32 cases, of polyp, 26 were successfully cultured and 6 failed. The culture lasted 5-23 days with 50%-95% viscosity of wells. By means of immuno-histochemical staining and electromicroscopy, the cultured cells were proved to be of epithelial origin.

CONCLUSION

The primary culture methods of adenoma cells have been improved, but further study on the serial transfer culture cell lines is most needed.

Microscopic self-organization in networks

We report our numerical studies on microscopic self-organization of a reaction system in three types of differently connected networks: a regular network, a small-world network, and a random network. Our simulation results show that the topology of the network has an important effect on the communication among reaction molecules, and plays an important role in microscopic self-organization. The correlation length among reacting molecules in a random or a small-world network is much shorter compared with that in a regular one. As a result, it is much easier to obtain microscopic self-organization in a small-world or a random network. We also observed a phase transition from a stochastic state to a synchronized state when we increased the randomness of a small-world network.

Dynamics of DNA-protein interaction deduced from in vitro DNA evolution

We report the first experimental study of the dynamics of in vitro evolution of DNA. Starting from a random pool of DNA sequences, we used cycles of selection (binding to the lac repressor protein), amplification, and mutations to evolve to a unique DNA sequence, the lac operator. Statistical analysis of the DNA sequences obtained during the cycles of evolution shows that the DNA bases are selected at different rates. The rates of selection provide a quantitative measure of the interaction of the DNA bases with the protein during the complex formation. A model reproduces the evolution dynamics of the DNA population but cannot give the fine structure of the DNA-protein interaction.

[Study on gastric motility and its relevant factors in type 2 diabetes]

OBJECTIVE

In this study radionuclide semi-liquid gastric emptying (GE) study was adopted to test the gastric motility in 129 patients with type 2 diabetes. Further study was made to explore the relationship between gastric motility disorder of diabetes and the influential factors.

METHODS

The variables to be measured and analyzed were age, BMI, duration of illness, level of glycemia, HbAlc, plasma insulin, motilin, gastrin, glucagon and Mg2+.

RESULTS

Of the 129 cases, 80 had delayed GE with an occurrence of 62.02%, and there was a close correlation between gastric motility disorder and the duration of illness, BMI, FPG, PPG, serum insulin, motilin levels and HbAlc as well.

CONCLUSION

These findings imply that gastric motility disorder of diabetes is influenced by multiple factors. The results also suggest that gastric motiligy disorder is much more common than expected, and radionuclide gastric emptying test is a useful aid for the early detection of this clinical entity.

[Study on the effect of COX-2's selective inhibitor on human colorectal adenoma cells proliferation]

OBJECTIVE

To investigate the mechanism of COX-2's selective inhibitor, NS-398, on human colorectal adenoma development.

METHODS

The human colorectal adenoma cells were isolated and cultured identified. The cell growth rates were assessed, when treated with NS-398, by using MTT method. Expression of COX-2 protein in human colorectal tumor was examined by immunohistochemistry.

RESULTS

23 of 30 colorectal adenomas were primary cultured successfully. NS-398 inhibited the proliferation of the cells in a dose- and time-dependent manner. COX-2 was overexpressed in colorectal adenoma(83.1%) and cancer(80.0%)compared with normal colon mucosa.

CONCLUSION

The key of the several culture conditions for the survival of human colorectal adenoma cells have been improved. Such as, best of the digestive time and number of cell. The cells can be inhibited by NS-398 with dose-dependent. Overexpression of COX-2 protein occurs early during colorectal carcinogenesis which contribute to tumour formation.

Reduction of the oxidative injury to the rabbits with established atherosclerosis by protein bound polysaccharide from Coriolus vesicolor

Recent evidence has emerged that macrophage glutathione (GSH) content and selenium dependent glutathione peroxidase (SeGSHPx) activity are inversely related to cell-mediated oxidation of LDL, and intervention means to enhance the macrophage GSH-SeGSHPx status may contribute to attenuation of the atherosclerotic process. Our previous works showed that protein bound polysaccharide (PSK) injected intraperitoneally could enhance SeGSHPx activity and mRNA content of mouse macrophages. The aim of the present study is to demonstrate whether PSK can reduce the oxidative injury to the established atherosclerotic rabbits. Using the established atherosclerotic rabbit model, we studied the effect of PSK on oxidatively modified LDL (Ox-LDL), lipoperoxide (LPO) cholesterol contents and SeGSHPx activities of plasma and tissues (aorta, heart and liver) in the established atherosclerotic rabbits. As compared with the control group, Ox-LDL, LPO and cholesterol contents were much lower; SeGSHPx activities and SeGSHPx/LPO ratios were much higher in plasma and tissues (aorta, heart and liver); and the lesion area of aortae was reduced in the PSK group. Through the increment of SeGSHPx activity in macrophages and aortae, PSK enhances their antioxidation potentiality and improves the antioxidant/prooxidant imbalance in them, and thus decreases Ox-LDL, LPO and cholesterol contents of plasma and tissues, and regresses lesion area of aortae in the established atherosclerotic rabbits.

Escape mechanisms in tumor immunity: a year 2000 update

The current consensus of opinion has it that most or possibly all tumors, spontaneous as well as induced, are immunogenic, expressing antigens in a form recognizable by the host immune system. Accordingly, in order to progress, tumors have to evolve strategies for evading immune responses. The purpose of this review is to consider the current status of knowledge concerning these different tumor escape strategies. It represents an update of an article originally published in this journal in 1997 (Pawelec, Zeuthen, and Kiessling, 1997). Therefore, it focuses mostly on publications that have appeared since then, illustrating the impressive accumulation of new data since that time and the importance currently attributed to studies of tumor escape from the immune response.