Fucoidan from Sargassum hemiphyllum inhibits infection and inflammation of Helicobacter pylori.

Having infected by Helicobacter pylori, the infection often leads to gastritis, gastric ulcer, or even gastric cancer. The disease is typically treated with antibiotics as they used to effectively inhibit or kill H. pylori, thus reducing the incidence of gastric adenoma and cancer to significant extent. H. pylori, however, has developed drug resistance to many clinically used antibiotics over the years, highlighting the crisis of antibiotic failure during the H. pylori treatment. We report here that the fucoidan from Sargassum hemiphyllum can significantly reduce the infection of H. pylori without developing to drug resistance. Fucoidan appears to be a strong anti-inflammation agent as manifested by the RAW264.7 cell model examination. Fucoidan can prohibit H. pylori adhesion to host cells, thereby reducing the infection rate by 60%, especially in post treatment in the AGS cell model assay. Mechanistically, fucoidan intervenes the adhesion of BabA and AlpA of H. pylori significantly lowering the total count of H. pylori and the level of IL-6 and TNF-α in vivo. These results all converge on the same fact that fucoidan is an effective agent in a position to protect the stomach from the H. pylori infection by reducing both the total count and induced inflammation.

Gastric Enzyme Supplementation Inhibits Food Allergy in a BALB/c Mouse Model.

Impaired gastric digestion due to suppressed gastric acidity enhances the risk for food allergy development. In the current study, we aimed to evaluate the impact of a supported gastric digestion via application of a pharmaceutical gastric enzyme solution (GES) on food allergy development and allergic reactions in a BALB/c mouse model. The ability of the GES to restore hypoacidic conditions was tested in mice treated with gastric acid suppression medication. To evaluate the impact on allergic symptoms, mice were orally sensitized with ovalbumin (OVA) under gastric acid suppression and subjected to oral challenges with or without GES. The immune response was evaluated by measurement of antibody titers, cytokine levels, mucosal allergy effector cell influx and regulatory T-cell counts. Clinical response was objectified by core body temperature measurements after oral OVA challenge. Supplementation of GES transiently restored physiological pH levels in the stomach after pharmaceutical gastric acid suppression. During oral sensitization, supplementation of gastric enzymes significantly reduced systemic IgE, IgG1 and IgG2a levels and allergic symptoms. In food allergic mice, clinical symptoms were reduced by co-administration of the gastric enzyme solution. Support of gastric digestion efficiently prevents food allergy induction and alleviates clinical symptoms in our food allergy model.

Poor clinical outcomes of intratumoral dendritic cell-specific intercellular adhesion molecule 3-grabbing non-integrin-positive macrophages associated with immune evasion in gastric cancer.

AIM: Tumour-associated macrophages (TAMs) are prominent immune cells infiltrating in solid tumours with phenotypic and functional heterogeneity. However, the clinical significance of heterogeneous subtypes of TAMs in gastric cancer still remains obscure. Here, we aimed to explore the clinical significance of TAMs expressing dendritic cell-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) and its relevance with immune contexture in gastric cancer. METHODS: We selected 453 formalin-fixed and paraffin-embedded samples and 51 fresh tissue specimens of patients with gastric cancer from Zhongshan Hospital. The association of DC-SIGN+ macrophages with clinicopathological parameters, overall survival (OS) and responsiveness to fluorouracil-based adjuvant chemotherapy (ACT) was inspected. Immunohistochemistry (IHC) and flow cytometry (FCM) were applied to characterize immune cells in gastric cancer. RESULTS: We demonstrated that high intratumoral DC-SIGN+ macrophages infiltration predicted poor OS and inferior therapeutic responsiveness to fluorouracil-based ACT in patients with gastric cancer. Furthermore, higher infiltration of DC-SIGN+ macrophages indicated an increased number of Foxp3+ regulatory T cells (Tregs), CD8+ T cells and a higher ratio of Foxp3+/CD8+ within the tumour microenvironment (TME). In addition, CD8+ T cells in DC-SIGN+ macrophages high subgroup were functionally impaired, showing decreased interferon-γ (IFN-γ), granzyme B (GZMB) and perforin production yet elevated programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) expression. CONCLUSIONS: DC-SIGN+ macrophages were associated with immunoinvasive TME and indicated poor prognosis and inferior therapeutic responsiveness to fluorouracil-based ACT. DC-SIGN+ macrophages might be an independent prognosticator and a potential immunotherapeutic target for gastric cancer.

In-feed bambermycin medication induces anti-inflammatory effects and prevents parietal cell loss without influencing Helicobacter suis colonization in the stomach of mice.

The minimum inhibitory concentration of bambermycin on three porcine Helicobacter suis strains was shown to be 8 µg/mL. The effect of in-feed medication with this antibiotic on the course of a gastric infection with one of these strains, the host response and the gastric microbiota was determined in mice, as all of these parameters may be involved in gastric pathology. In H. suis infected mice which were not treated with bambermycin, an increased number of infiltrating B-cells, T-cells and macrophages in combination with a Th2 response was demonstrated, as well as a decreased parietal cell mass. Compared to this non-treated, infected group, in H. suis infected mice medicated with bambermycin, gastric H. suis colonization was not altered, but a decreased number of infiltrating T-cells, B-cells and macrophages as well as downregulated expressions of IL-1ß, IL-8M, IL-10 and IFN-γ were demonstrated and the parietal cell mass was not affected. In bambermycin treated mice that were not infected with H. suis, the number of infiltrating T-cells and expression of IL-1ß were lower than in non-infected mice that did not receive bambermycin. Gastric microbiota analysis indicated that the relative abundance of bacteria that might exert unfavorable effects on the host was decreased during bambermycin supplementation. In conclusion, bambermycin did not affect H. suis colonization, but decreased gastric inflammation and inhibited the effects of a H. suis infection on parietal cell loss. Not only direct interaction of H. suis with parietal cells, but also inflammation may play a role in death of these gastric acid producing cells.

Nutrition and Immune-Modulatory Intervention in Surgical Patients With Gastric Cancer.

This study evaluated the effect of an immune-modulatory diet on patients with gastric cancer and identified the parameters associated with postoperative outcomes. This was a single-arm prospective intervention study. At baseline, patients were assessed for nutrition (Patient-Generated Subjective Global Assessment), inflammatory markers (albumin, C-reactive protein, and interleukin 6 [IL-6]), and immune markers (percentage NK, CD4, CD8, and CD4:CD8 ratio); they also received nutrition counseling and high-calorie/protein supplement. A week before surgery, they were assessed for nutrition and inflammatory/immune markers and started on an immune-modulatory supplement until the day before surgery, when they were evaluated again. On the second postoperative day, patients were assessed for inflammatory/immune parameters, and a final nutrition evaluation was performed until the day of discharge. Complications were recorded daily and up to 30 days after discharge. Thirty-seven patients (60 ± 10 years old) were included, and 57% were classified as malnourished. Maintenance of nutrition and immune parameters occurred throughout the study period, but we found a preoperative increase in C-reactive protein (0.1-1.5 mg/dL) and IL-6 (2.0-14.2 pg/mL) and a postoperative increase in the CD4:CD8 ratio (2.3 ± 1.0). Complications and death were seen in 35%, especially patients with higher preoperative IL-6 (2.2-46 pg/mL), lower CD4:CD8 ratio (1.7 ± 0.5), and lower protein (1.2 ± 0.5 g/kg/d) and calorie intake (1552 ± 584 kcal/kg/d). The high-calorie/protein supplementation with the immune-modulating diet was able to maintain the nutrition and immune status of patients with gastric cancer.

Recombinant human lactoferrin enhances the efficacy of triple therapy in mice infected with Helicobacter pylori.

Helicobacter pylori (H. pylori) is a life-threatening pathogen which causes chronic gastritis, gastric ulcers and even stomach cancer. Treatment normally involves bacterial eradication; however, this type of treatment only has a rate of effectiveness of <80%. Thus, it is a matter of some urgency to develop new therapeutic strategies. Lactoferrin, a member of the transferrin family of iron-binding proteins, has been proven to be effective in removing a vast range of pathogens, including H. pylori. In the present study, we examined the effectiveness of recombinant human lactoferrin (rhLf) isolated from transgenic goats as a treatment for H. pylori in vitro and in vivo. For the in vivo experiments, BALB/c mice received an intragastric administration of 0.1 ml of a suspension of H. pylori. The mice were then divided into 4 groups: group A, treated with saline; group B, treated with 1.5 g of rhLF; group C, treated with the standard triple therapy regimen; and group D, treated with the standard triple therapy regimen plus.5 g of rhLF. Following sacrifice, the stomach tissues of the mice were histologically examined for the presence of bacteria. For the in vitro experiments, the bacteria were cultured in BHI broth and RT-qPCR and western blot analysis were carried out to determine the mRNA and protein levels of virulence factors (CagA and VacA) in the cultures. Our results revealed that rhLf not only inhibited the growth of H. pylori, but also suppressed the expression of two major virulence factors. Moreover, rhLf markedly increased bacterial eradication and effectively reduced the inflammatory response when combined with the standard triple therapy regimen. These results provide evidence supporting the use of rhLF as an adjuvant to traditional therapeutic strategies in the treatment of H. pylori.

A polysaccharide from Salvia miltiorrhiza Bunge improves immune function in gastric cancer rats.

A neutral polysaccharide fraction (SMPA) prepared from the roots of Salvia miltiorrhiza by DEAE-cellulose and Sephadex G-100 chromatography was tested for its immune enhancing function in N-methyl-N'-nitro-nitrosoguanidine (MNNG)-induced gastric cancer rats by intragastric administration. SMPA (200mg/kg) treatment not only increased the body weight, but also improved the immune organ indices. Furthermore, studies of various immunological activities in gastric cancer rats revealed that SMPA significantly stimulated splenocyte proliferation, promoted anti-inflammatory cytokines (IL-2, IL-4 and IL-10) production, inhibited pro-inflammatory cytokine (IL-6 and TNF-α) secretion, augmented the killing activity of natural killer (NK) cells and cytotoxic T lymphocytes (CTL), and increased phagocytotic function of macrophages in gastric cancer rats. In addition, SMPA administration evidently elevated total intracellular granzyme-B and IFN-γ levels produced by splenocytes in gastric cancer rats. Taken together, these results suggested that SMPA could act as an effective immunomodulator and might be explored as a potential supplemental source for gastric cancer therapy.

Efficacy and mechanism of action of yin lai tang (lung-stomach treatment) in dyspepsia mouse infected by FM1 virus.

The aim of this study was to assess the efficacy and elaborate the mechanism of action of Yin Lai Tang (Lung-Stomach Treatment) on dyspepsia mouse infected by FM1 virus. Ninety male, 4 week old Kunming mouse with 12-14 g weight, were randomly divided into 9 groups, i.e., normal, infected, dyspepsia, ribavirin, Shuanghuanglian, Children's indigestion tablet, YinLaiTang high dose, YinLaiTang middle dose and YinLaiTang low dose, and these groups had been treated by according drugs to get objectives. Compared with normal group, lung index significantly (p < 0.01) increased in all groups except ribavirin group where lung index obviously (p < 0.05) increased. There was non-significant (p > 0.05) difference in the values of lung homogenate virus titer between dyspepsia group and other groups. Compared to normal group, there was variable degree of inflammatory cell infiltrations in respiratory tract structures in the animals of other groups, and there was a significant (p < 0.01) increase in the level of serum IL-6, IL-10, and TNF-alpha in infected and dyspepsia group and significant (p < 0.01) decrease in the level of serum IFN-gamma was observed. Compared with single clearing stomach method and single clearing lung approach, lung-stomach treatment reduced the level of IL-6 with non-significant difference (p > 0.05) and increased the level of IL-10 obviously, and compared with the single clearing lung method, there was a significant difference (p < 0.05). Compared with the single clearing stomach method and the single clearing lung method, the lung-stomach treatment method had a better efficacy and showed effects on the expression of pro-inflammatory factor and anti-inflammatory factor.

[Effect of jianpi yiqi qingyou decoction on lymphocyte subsets and IL-2 mRNA in gastric tissue in rats with chronic superficial gastritis].

OBJECTIVE: To investigate the effect of Jianpi Yiqi Qingyou decoction on lymphocyte subsets and IL-2 mRNA in gastric tissue in rats with chronic superficial gastritis. METHOD: Wistar rats were randomly divided into 6 groups (11 for each): a blank control groups, the model of the control groups, the treatment groups (low-dose groups of traditional Chinese medicine, moderate-dose groups of traditional Chinese medicine, high-dose groups of traditional Chinese medicine) and lansoprazole groups. The models were made with the method in reference except a blank control groups. These rats are drinking freely with 0. 02% ammonia, continuous 90 days, and made preparations for experimental animal model of superficial gastritis. Making the model were detected by HE dying. The count of CD3+, CD4+ and CD8+ T cells were detected by immunohistochemistry. Using reverse transcriptase polymerase chain reaction (RT-PCR), the expression levels of IL-2 mRNA in gastric tissue were quantified. RESULT: Compared with that in model groups, the content of CD3+ T cells and CD4+ T cells in gastric tissue obviously increased in high dose of traditional Chinese medicine groups , the content of CD8+ T cells in gastric tissue obviously decreased in high dose of traditional Chinese medicine groups and the difference was significant (P < 0.01). The expression levels of IL-2 mRNA in gastric tissue obviously increased in moderate and high doses of traditional Chinese medicine groups, and the difference was significant compared with that in model group (P < 0.01). CONCLUSION: Jianpi Yiqi Qingyou decoction can obviously improve the content of CD3+ T cells and CD4+ T cells and the expression levels of IL-2 mRNA, decrease the content of CD8+ T cells in gastric tissue, improve immunity of rats. So the research results can provide some evidences for the treatment for chronic superficial gastritis.

Inhibitory effects of Japanese apricot (Prunus mume Siebold et Zucc.; Ume) on Helicobacter pylori-related chronic gastritis.

OBJECTIVES: We investigated the correlation between Japanese apricot (JA) intake and Helicobacter pylori-related chronic atrophic gastritis (CAG). METHODS: A questionnaire was administered and serum anti-H. pylori IgG antibodies measured in 1358 asymptomatic adults. The subjects were divided into high-intake and low-intake groups. Histological and serological evaluation of H. pylori-related CAG was performed in 68 non-elderly volunteers. RESULTS: The H. pylori-negative rate did not differ significantly between the high-intake and low-intake groups. Mean antibody titers were lower in the high-intake group, but the difference was not significant. There was no significant difference in the rate of H. pylori infection on the basis of JA intake when subjects were stratified by age. Among H. pylori-positive non-elderly subjects, antibody titers were significantly lower in the high-intake group (P=0.041). Endoscopic tissue biopsy from the 68 volunteers showed less H. pylori bacterial load and mononuclear infiltration irrespective of gastric site in the high-intake group. In the high-intake group, antral neutrophil infiltration was significantly less pronounced and corporal atrophy was less extensive. Serological evaluation using serum PG levels also confirmed these histopathological data. CONCLUSIONS: Our findings strongly indicate a preventive effect of JA intake on CAG by inhibiting H. pylori infection and reducing active mucosal inflammation.

Linear and branched beta(1-3) D-glucans activate but do not prime teleost macrophages in vitro and are inactivated by dilute acid: implications for dietary immunostimulation.

Beta(1-3) glucans are a diverse range of carbohydrate polymers of differing lengths and structures that make up the cell walls of yeast, fungi, algae and some plants and activate innate immune responses in plants, invertebrates and higher animals. Consequently glucans are often used as dietary immunostimulants in commercial feeds for aquacultured fish species. The present study investigates the capability of purified glucans of differing structures and configurations, including curdlan, paramylon, laminarin and purified yeast beta glucan to activate innate immunity in vitro using barramundi pronephros macrophages as a model, and compares them to Zymosan, a complex mixture derived from yeast cell walls, and lipopolysaccharide from Gram negative bacteria. All of the glucans were able to stimulate respiratory burst in barramundi macrophages at concentrations of 100 microg/mL and 1000 microg/mL, with curdlan eliciting the highest respiratory burst response at 1000 microg/mL. LPS and Zymosan were the only immunostimulants tested that could prime barramundi macrophages by incubating with low concentrations (0.1 and 1 microg/mL) for 24 h before triggering respiratory burst with PMA, suggesting teleost macrophages may not prime through the glucan receptor. As glucans are used as dietary immunostimulants, the pH of the barramundi stomach was assayed for 6 h following feeding and indicated that pH was as low as 2 for up to 6 h. Treating the glucans with dilute HCl at pH 2 completely neutralised their macrophage-activating capability. These results are important as they indicate that glucans do not prime barramundi macrophages but will activate them at high concentrations. However, it is debatable whether glucans will have any effect on macrophages if administered in the diet due to the combination of high concentration required and probable hydrolysis of the polymer structures as they pass through the acid environment of the stomach.

In vitro and in vivo efficacies of amlodipine against Listeria monocytogenes.

Listeria monocytogenes causes suppurative gastritis in BALB/c mice. We investigated the effect of the antihypertensive drug amlodipine (Aml) on the growth of L. monocytogenes in vitro and in vivo. Aml showed noteworthy inhibitory action (minimum inhibitory concentration, MIC(90) 32 microg/ml) against Listeria strains and demonstrated cidal (minimum bactericidal concentration, MBC 64 microg/ml) activity. Aml administered orally at 2.5 microg/g in female BALB/c mice for 7 days, commencing 4 days before oral challenge (1 x 10(8) CFU/ml with L. monocytogenes ATCC 51774), significantly reduced bacterial counts in the stomach (P < 0.01), liver (P < 0.01), and spleen (P < 0.05), and decreased (P < 0.05) gastric lesions, neutrophilic infiltration, edema, vascular degeneration, and necrosis of gastric tissues. It caused the down-regulation of expression of inflammatory cytokines (IFN-gamma, IL-1 beta, and TNF-alpha) compared to drug-free control. Aml may be used in the presence of an antibiotic as adjunct therapy that boosts the host immunity against Listeria. Further, QSAR studies might contribute in manipulating it as a lead compound for the synthesis of new, more effective non-antibiotics (helper compounds), perhaps devoid of side-effects, that could be recommended as compassionate therapy for listeriosis.

Murine model of buckwheat allergy by intragastric sensitization with fresh buckwheat flour extract.

Food allergies affect about 4% of the Korean population, and buckwheat allergy is one of the most severe food allergies in Korea. The purpose of the present study was to develop a murine model of IgE-mediated buckwheat hypersensitivity induced by intragastric sensitization. Young female C3H/HeJ mice were sensitized and challenged intragastricly with fresh buckwheat flour (1, 5, 25 mg/dose of proteins) mixed in cholera toxin, followed by intragastric challenge. Anaphylactic reactions, antigen-specific antibodies, splenocytes proliferation assays and cytokine productions were evaluated. Oral buckwheat challenges of sensitized mice provoked anaphylactic reactions such as severe scratch, perioral/periorbital swellings, or decreased activity. Reactions were associated with elevated levels of buckwheatspecific IgE antibodies. Splenocytes from buckwheat allergic mice exhibited significantly greater proliferative responses to buckwheat than non-allergic mice. Buckwheat-stimulated IL-4, IL-5, and INF-gamma productions were associated with elevated levels of buckwheat-specific IgE in sensitized mice. In this model, 1 mg and 5 mg dose of sensitization produced almost the same degree of Th2-directed immune response, however, a 25 mg dose showed blunted antibody responses. In conclusion, we developed IgE-mediated buckwheat allergy by intragastric sensitization and challenge, and this model could provide a good tool for future studies.

[Changes in local humoral immunity during stomach ulcer healing with laser and drug therapy]. / Izmenenie mestnogo gumoral'nogo immuniteta v protsesse zazhivleniia iazv zheludka pod vliianiem lazernoi i medikamentoznoi terapii.

The increase of the contents of serum IgA, IgG, IgM on the edge of long non-cicatrizing gastric ulcer was determined. At the same time the level of SIgA decreased in comparison with unaltered gastric mucosa. It is shown that the immunoglobulin content in the healed ulcer cicatrice depended on treatment method. The medicamentous therapy was accompanied by lowering of the contents of IgG, IgA, SIgA and by some increase of IgM level. The laser therapy is characterized by lowering of IgA, IgG, IgM level on a background of significant increase of SIgA content. The local humoral immunity after laser therapy was the same as in persons with unaltered gastric mucosa.

Inhibitory effects of catechins on neutrophil-dependent gastric inflammation.

The inhibitory effects of tea against carcinogenesis have been attributed to the biological activity of the polyphenol fraction of tea. However, the molecular mechanisms of these effects are not completely understood. Chronic inflammation induced by Helicobacterpylori has been proposed to be a causative pathway in the carcinogenesis of stomach cancer. Therefore, an agent possessing anti-inflammatory properties may be chemopreventative against stomach cancer. In the present study, we have investigated the anti-inflammatory effects of tea catechins. After addition of IL-1beta to MKN45 cells, a gastric cancer cell line, or human umbilical vein endothelial cells (HUVECs), IL-8 production was detected in supernatants. This IL-8 production was inhibited by catechins. Incubation of HUVECs or polymorphonuclear leukocytes (PMNs) with IL-1beta or IL-8, respectively, resulted in an increased surface expression of adhesion molecules. Catechins also inhibited this expression of adhesion molecules on HUVECs and PMNs. Of these major effects, the strongest effect of catechins was to reduce expression of the adhesion molecules CD1lb and CD18 on PMNs. These results suggest that tea may inhibit carcinogenesis partly through the anti-inflammatory effects of tea catechins on PMN-dependent gastric mucosal inflammation.

Characterisation of proton pump antibodies and stomach pathology in gastritis induced by neonatal immunisation without adjuvant.

It has previously been reported that neonatal BALB.D2 mice injected with native proton pump antigens without adjuvant develop an irreversible gastritis (Claeys et al, 1997). The ease of inititating gastritis in the neonate stands in contrast with the difficulty in initiating gastritis in adult mice that require repeated immunisation in adjuvant that is reversible following cessation of immunisation (Scarff et al, 1997). In view of these contrasting observations, we set out to ascertain whether we could confirm the observations in neonatal mice as well as further characterise the pathology and the autoantibody response. We found that neonatal gastritis-susceptible BALB/c mice (n=12), immunised with either pig or mouse gastric membranes in the absence of adjuvant, develop gastritis without circulating antibody to parietal cells detected by immunofluorescence, a hallmark of murine and human gastritis (Toh et al, 1997). However, mice immunized with pig gastric membranes (n=6) had circulating antibodies reactive by immunofluorescence to recombinant alpha and/or beta subunit of gastric H+/K+-ATPase expressed by insect cells (Sfalpha and Sfbeta). Four mice from this cohort with antibodies to Sfbeta also had reactivity to gastric H+/K+-ATPase by ELISA, and 3 immunoblotted the beta but not the alpha subunit of the ATPase. In the cohort of mice immunised with mouse gastric membranes (n=6), four produced antibodies reactive by immunofluorescence to Sfalpha, two of which were also reactive to Sfbeta and one developed antibodies detected by ELISA to gastric H+/K+-ATPase. However, no members of this cohort had antibodies reactive by immunoblotting to either the beta or alpha subunit of the ATPase. In all cases gastritic stomachs were characterised by areas deficient in ribosome-rich zymogenic cells and marked reductions in H+/K+-ATPase-positive parietal cells. Metaplasia detected by Maxwell stain, as clusters of mucus-producing cells throughout gastric units, were non-reactive to stomach mucin autoantibody suggesting the mucins comprise other and/or aberrant form(s). Compared to our previous observations in adult mice, our present data confirms that gastric autoimmunity is more readily induced in the neonate than the adult. Our data also affirms that while the neonatal immune system can mount a damaging inflammatory cellular immune response to gastric antigens, it develops an altered antibody response.

Associated thyrogastric autoimmunity increases the prevalence of low erythrocyte magnesium in type 1 diabetes.

A group of 230 type 1 (insulin-dependent) diabetic patients were screened for the presence of thyrogastric autoantibodies (aTPO and PCA) and magnesium depletion. Thirty-seven per cent presented with significant levels of 1 autoantibody and 7 per cent were positive for both. Exactly 25 per cent of the subjects had low levels of erythrocyte Mg (RBC-Mg < 5.5 mg/dl). Female patients were more prone to lower RBC-Mg and had a significant higher prevalence of aTPO and, although actually euthyroid, had a more pronounced history of thyroid disease. The presence of both antibodies was accompanied with the highest prevalence of low RBC-Mg. However, PCA positivity with hypergastrinaemia alone did not show a significant increase of the Mg depletion. The mechanisms involved in this phenomenon remain unclear but besides gender, duration of diabetes and the metabolic consequences of the disease, the presence of associated thyroid and gastric dysfunction can play a supplementary role in the maintenance of the chronic Mg problems in type 1 diabetes.

Immunohistochemical signal amplification by catalyzed reporter deposition and its application in double immunostaining.

The biotinyl-tyramide substrate of the horseradish peroxidase enzyme has been recently introduced to amplify immunohistochemical signals. We applied either fluorochromeor biotin-conjugated tyramine to improve the detection of different antigens in sections of rat stomach, pancreas, and hypothalamus. A ten- to 100-fold increase in staining efficiency was achieved, depending on the antibody, with either fluorescent or peroxidase detection systems. The amplification method was particularly useful for increasing a weak signal of conventional immunostaining caused by suboptimal tissue fixation. At a very low concentration of the primary antibody, the antigen can no longer be detected by a conventional fluorescent secondary antibody but is still detectable after amplification. When an antibody is used at this very low concentration and is detected by a fluorescent amplification method, another primary antibody, raised in the same host species, can be used and demonstrated with a different fluorochrome in subsequent conventional immunostaining of the same section. In this way it becomes possible to immunostain the same section with two different primary antibodies raised in the same host species. Samples for such double immunostaining are demonstrated here using pairs of monoclonal antibodies (to tyrosine hydroxylase and oxytocin) in the hypothalamus and polyclonal antibodies (to glucagon and neurofilament M) in sections of rat pancreas. Because in many cases the availability of antibodies is limited, the amplification method can be a quick and efficient tool for double immunostaining with antibodies from the same host species.

Antibody responses of mice to intragastric and parenterally administered aeroallergens.

Intragastric administration of aeroallergens (pollen extract)-primed mice to produce transient serum IgE antibody responses following subsequent parenteral stimulation while the same initial dose of extract, given parenterally, did not have this effect. In previously immunized animals, intragastric administration of pollen extract was found to enhance systemic antibody production. These observations indicate that exposure of gut-associated lymphoid tissue to aeroallergens can have a profound effect on subsequent reaginic antibody production. This procedure provides a useful model for studying IgE responses to allergens without the complication of an initial injection with adjuvant. A combination of parenteral immunization with oral administration may therefore offer a convenient immunotherapeutic manoeuvre for patients with seasonal rhinitis/asthma.

Autoantibodies and their clinical significance in a black vitiligo population.

The frequency of autoantibodies was determined in 70 black vitiligo patients and controls. Both groups were screened for antithyroid, antinuclear, antigastric parietal cell, anti-smooth muscle cell, and antimitochondrial autoantibodies. The significance of autoantibodies was determined in vitiligo patients by correlating their presence or absence with various clinical features of the patients. The overall frequencies of autoimmune and endocrine diseases were also assessed in vitiligo patients, controls, and their respective families. Vitiligo patients had an increased frequency of antithyroid antibodies and an increased frequency of autoimmune and/or endocrine diseases. These diseases included, especially, hyperthyroidism, hypothyroidism, and alopecia areata. Autoantibody-positive vitiligo patients had an increased frequency of first- and second-degree relatives having autoimmune and/or endocrine diseases. These findings tend to support an autoimmune cause of vitiligo in black patients.