[Mechanism of lysosome-mediated eradication activity of macrophages on specific anti-Helicobacter pylori of patchouli alcohol].

The aim of this paper is to investigate the effect of patchouli alcohol in enhancing Helicobater pylori's action in eradicating macrophages and its mechanism. H. pylori was co-cultured with macrophages at a ratio of MOI=100 in different concentrations of patchouli alcohol. The effect of patchouli alcohol in eradicating macrophages was detected by agar dilution method. The effect of patchouli alcohol on NO and myeloperoxidase (MPO) levels in macrophages were measured by H. pylori by biochemical methods. Patchouli alcohol effect on H. pylori-induced pro-inflammatory gene expression and protein secretion in macrophages were detected by RT-qPCR and ELISA method. The eradication of H. pylori has significantly enhanced, and the destabilization of lysosomes has been reversed. Meanwhile, patchouli alcohol has an effect in inhibiting pro-inflammation and oxidation. The mechanism of patchouli alcohol in eradicating H. pylori and resisting oxidative stress may be associated to the blocking of bacteria escape lysosome combination procedures.

Regulation of NKG2D-Dependent NK Cell Functions: The Yin and the Yang of Receptor Endocytosis.

Natural-killer receptor group 2, member D (NKG2D) is a well characterized natural killer (NK) cell activating receptor that recognizes several ligands poorly expressed on healthy cells but up-regulated upon stressing stimuli in the context of cancer or viral infection. Although NKG2D ligands represent danger signals that render target cells more susceptible to NK cell lysis, accumulating evidence demonstrates that persistent exposure to ligand-expressing cells causes the decrease of NKG2D surface expression leading to a functional impairment of NKG2D-dependent NK cell functions. Upon ligand binding, NKG2D is internalized from the plasma membrane and sorted to lysosomes for degradation. However, receptor endocytosis is not only a mechanism of receptor clearance from the cell surface, but is also required for the proper activation of signalling events leading to the functional program of NK cells. This review is aimed at providing a summary of current literature relevant to the molecular mechanisms leading to NKG2D down-modulation with particular emphasis given to the role of NKG2D endocytosis in both receptor degradation and signal propagation. Examples of chronic ligand-induced down-regulation of NK cell activating receptors other than NKG2D, including natural cytotoxicity receptors (NCRs), DNAX accessory molecule-1 (DNAM1) and CD16, will be also discussed.

Extracellular ATP induces unconventional release of glyceraldehyde-3-phosphate dehydrogenase from microglial cells.

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a key glycolytic enzyme that is predominantly localized in the cytoplasm. However, recent studies have suggested that GAPDH is released by various cells and that extracellular GAPDH is involved in the regulation of neuritogenesis in neuronal cells. It has also been reported that GAPDH is expressed on the surfaces of macrophages and functions as a transferrin receptor. However, since GAPDH is a leaderless protein the mechanisms by which it reaches the extracellular environment remain unclear. Here, we examined the role of P2X7 receptor (P2X7R), an ATP-gated cation channel, in the unconventional release of GAPDH from microglial cells, the resident macrophages in the brain. The activation of P2X7R by ATP triggered GAPDH release from lipopolysaccharide (LPS)-primed microglial cells. ATP-induced microvesicle formation, exosome release, and K(+) efflux followed by caspase-1 activation are likely involved in the GAPDH release, but ATP-induced dilatation of membrane pores and lysosome exocytosis are not. It was also demonstrated that exogenous GAPDH facilitated LPS-induced phosphorylation of p38 MAP kinase in microglial cells. These findings suggest that P2X7R plays an important role in the unconventional release of GAPDH from microglial cells, and the GAPDH released into the extracellular space might be involved in the regulation of the neuroinflammatory response in the brain.

Inflammasome-dependent and -independent IL-18 production mediates immunity to the ISCOMATRIX adjuvant.

Adjuvants are an essential component of modern vaccines and used for their ability to elicit immunity to coadministered Ags. Many adjuvants in clinical development are particulates, but how they drive innate and adaptive immune responses remains poorly understood. Studies have shown that a number of vaccine adjuvants activate inflammasome pathways in isolated APCs. However, the contribution of inflammasome activation to vaccine-mediated immunity in vivo remains controversial. In this study, we evaluated immune cell responses to the ISCOMATRIX adjuvant (IMX) in mice. Like other particulate vaccine adjuvants, IMX potently activated the NALP-3-ASC-Caspase-1 inflammasome in APCs, leading to IL-1ß and IL-18 production. The IL-18R pathway, but not IL-1R, was required for early innate and subsequent cellular immune responses to a model IMX vaccine. APCs directly exposed to IMX underwent an endosome-mediated cell-death response, which we propose initiates inflammatory events locally at the injection site. Importantly, both inflammasome-related and -unrelated pathways contributed to IL-18 dependence in vivo following IMX administration. TNF-α provided a physiological priming signal for inflammasome-dependent IL-18 production by APCs, which correlated with reduced vaccine-mediated immune cell responses in TNF-α- or TNFR-deficient mice. Taken together, our findings highlight an important disconnect between the mechanisms of vaccine adjuvant action in vitro versus in vivo.

Anti-inflammatory and antiulcerogenic activities of leaf extracts and sesquiterpene from Teucrium ramosissimum (Lamiaceae).

Teucrium ramosissimum (Lamiaceae) is a native and endemic medicinal plant from South of Tunisia traditionally used for the treatment of many diseases. The anti-inflammatory and antiulcerogenic activities of sesquiterpene (ß-eudesmol), chloroform, and ethyl acetate leaf extracts from T. ramosissimum were assayed. Macrophage phagocytic activity and lymphocyte proliferation in the absence and presence of mitogens (lipopolysaccharide [LPS] or lectin) were investigated. Depending on the concentrations, the extracts affect macrophage functions by modulating their lysosomal enzyme activity and nitric oxide (NO) release. For lymphocyte proliferation assay, tested extracts enhance significantly cell proliferation either with or without mitogen stimulation. These results suggest that leaf extracts from T. ramosissimum contain potent components such as flavonoids that may be potentially useful for modulating immune cell functions in physiological and pathological conditions. Antiulcerogenic activity was examined on rat ethanol-induced ulcerogenic model. Compared with control (cimetidine), leaf extracts from T. ramosissimum exert different protective effects against ethanol-induced ulcerogenesis.

Stimulation of innate immunity by oral administration of dahi containing probiotic Lactobacillus casei in mice.

Immunomodulatory effects of a dahi (strained yogurt) containing probiotic Lactobacillus casei, designated "probiotic dahi," was evaluated in Swiss albino mice during 8 days of feeding and compared with control dahi-, nonfermented milk-, and no milk product diet-fed (control) groups. Lysosomal enzymes (beta-galactosidase and beta-glucuronidase) and phagocytic activities were estimated in peritoneal macrophages of animals fed with different experimental diets on days 2, 5, and 8. The oral administration of probiotic dahi increased (by 84%) beta-galactosidase activity in supernatant of cultured macrophages and achieved the highest values on day 2 and thereafter decreased up to day 8, at which no effect on beta-glucuronidase activities was observed; it was the same as the control group. Moreover, phagocytic activity also increased in probiotic dahi-fed mice after days 2 and 5 and then decreased after 8 days, but was still higher than in nonfermented milk and control dahi-fed groups. The counts of total lactobacilli significantly increased after feeding of probiotic dahi as compared to the other groups. However, no significant changes were observed in beta-galactosidase and beta-glucuronidase activities and phagocytic activity of peritoneal macrophages isolated from nonfermented milk- and normal diet-fed groups. The results of the present study reveal that nonspecific immune response markers were stimulated in mice by feeding of probiotic dahi containing probiotic L. casei instead of milk alone and that the effect was greater than in control dahi.

The role of H2-O and HLA-DO in major histocompatibility complex class II-restricted antigen processing and presentation.

The function of major histocompatibility complex (MHC) class II molecules is to sample exogenous antigens for presentation to CD4+ T helper cells. After synthesis in the endoplasmic reticulum, class II molecules are directed into the endosomal system by association with the invariant chain (Ii), which is sequentially cleaved, generating class II dimers loaded with Ii-derived peptides (CLIP). These class II-peptide complexes are physiological substrates for H2-M/HLA-DM, a resident of the endosomal/lysosomal system which facilitates the removal of CLIP from newly synthesised class II alpha beta dimers. Exchange of CLIP for antigenic class II-binding peptides is also promoted by the action of H2-M/HLA-DM, resulting in stable peptide-class II complexes that are transported to the cell surface for presentation to CD4+ T cells. Recent evidence suggests that this H2-M/HLA-DM-mediated 'peptide editing' is influenced by another MHC class II-encoded molecule, H2-O/HLA-DO. This non-polymorphic alpha beta heterodimer is associated with H2-M/HLA-DM during intracellular transport and within the endosomal system of B cells. H2-O/HLA-DO alters the peptide exchange function of H2-M/HLA-DM in a pH-dependent manner, so that H2-M/HLA-DM activity is limited to more acidic conditions, corresponding to lysosomal compartments. Indeed, H2-O/HLA-DO may serve to limit the presentation of antigens after fluid phase uptake by B cells, while augmenting presentation of antigens internalised via membrane Ig receptors. Such a mechanism may maintain the fidelity of the B-cell-CD4+ T-cell interaction, counteracting self reactivity arising from less stringent lymphocyte activation. Here, data evaluating the role of H2-O/HLA-DO shall be reviewed and its putative function discussed.

Papel dos lisossomos nos processos inflamatórios: efeitos do ion zinco sobre os componentes do compartimento lisossômico / Paper of lysossomes of the effects inflamatory of zinc ion about the components of the lysosomal compartment

Perde-se no tempo o interesse que a inflamaçäo tem despertado no espírito dos mais curiosos. Desde a Mesopotâmia, passando pelo Egito antigo, por Celsus que viveu em torno do anos 30 de nossa era, quando escreveu os quatro sinais clínicos característicos: rubor, tumefaçäo, calor e dor, por Virchow (1859) que introduziu "a perda da funçäo, até nossos dias, quando SEYLE a resumiu como sendo respostas a estímulos diversos, imediatas, näo específicas as quais denominou de "estresse localizado" e mediatas, portando, tardias e específicas. Muitos dos processos envolvidos na reaçäo inflamatória säo considerados efeitos de agentes químicos, liberados "in situ", chamados mediadores externos, normalmente de origem bacteriana e, endógenos, originários tanto do plasma, quanto do tecido inflamado. Dentre estes últimos, destacam-se os sistemas de cininas, de complementos de coagulaçäo, as aminas vasoativas, os derivados prostanoides e eicosanoides e, principalmente, aqueles efetores da inflamaçäo, de origem lisossômica. O potencial de mediadores liberados a partir dos diversos componentes do compartimento lisossômico, principalmente, de leucócitos e de outras células envolvidas com a inflamaçäo, inclusive as plaquetas, é constituido, essencialmente de proteínas catiônicas, de hidrolases ácidas e de hidrolase neutras. Todo este conteúdo intralisossómico está preservado em estado latente, por um complexo membranoso de estrutura lipoproteica, cuja integridade fisio-química é de extrema importâncaia para o desencadeamento e/ou manutençäo do processo inflamatório. Inúmeras substâncias, destacando-se entre elas, os corticoesteroides, aspirina, colchicina, indometacina, vários antiinflamatórios näo esteroides, diversos polifenois, derivados quinoleínicos, além de determinados íons metálicos, a exemplo do ouro, tem sido descritas como estabilizadoras das membranas lisossômicas. Diante do exposto, estudou-se neste trabalho, oes efeitos decorrentes dos tratamentos "in vitro" e " in vivo", pelos íons zinco, de processos inflamatórios provocados pelo óleo de corton, injetado subcutaneamente em ratos. Os resultados obtidos das avaliaçöes bioquímicas das atividades lisossômicas, das observaçöes por microscopia eletrônica dos diversos componentes do compartimento lisossômico e dos estudos microanalíticos, efetuados, principalmente, sobre heterofagolisossomos e corpúsculos residuais, permitiram concluir que os íons zinco säo excelentes estabilizadores das membranas lisossômicas, tanto

[Changes in lysosomal activity of beta-glucuronidase in leukocytes of rats exposed to benzene under selenic protection]. / Zmiany aktywnosci lizosomalnej beta-glukuronidazy w leukocytach szczurów przewlekle eksponowanych na benzen w oslonie selenowej.

The authors demonstrated that a chronic exposure to benzene caused in rats a reduction in the number of lymphocytes in peripheral blood, decrease in beta-glucoronidase (BG) activity in neutrophils and increase in BG-positive lymphocytes fraction. In addition, a failure was found in lysosomes of lymphocytes, revealed by scattering of a given enzyme in cytoplasma. Administration of 1.0 microgram/kg for 10 consecutive days before benzene exposure, did not prevent lymphocytopenia but hampered BG activity decrease in neutrophils as well as a damage to lymphocytic lysosomes. Administration of 5.0 microgram/kg for 10 successive days prior to benzene exposure, prevented lymphocytopenia and caused a reactive increase in the amount of neutrophils and resulted in an increase of BG-positive lymphocytes fraction, especially those with cytoplasmatic localization of enzyme. The results obtained demonstrate that only a smaller dose of selenium protected lysosomal membrane of lymphocytes from toxic effects of benzene, whereas both selenium doses protect BG in neutrophils.

The effect of ubiquinone-7 and its metabolites on the immune response. II. Adjuvant activity on the circulating antibody production and the effect on the liver lysosomal membrane.

The effects of the fat-soluble vitamins (retinol, alpha-tocopherol, phylloquinone and ubiquinone) and their related compounds were investigated on the immune response in vivo. E acid-I, dihydro E acid-I, ES-6, K acid-I, Q acid-II and QS-3 act as adjuvants on the production of circulating antibody to bacterial alpha-amylase in mice when they are immunized with in the water phase of water-in-oil emulsion. These compounds, however, can not act as adjuvants in enhancing helper activity of carrier-primed T-cells using an adoptive transfer system in mice. It is also shown that these compounds have no adjuvant activity on the development of delayed type hypersensitivity to ABA-N-acetyltyrosine in guinea pigs. No definite correlation between the adjuvant activity of these compounds and their labilizing activity on rat-liver lysosomal membrane was found.

[The influence of anterior and posterior hypothalamic structures on the engulfment and digestion of an antigen by macrophages and on India ink clearance]. / Vliianie struktur perednego i zadnego gipotalamusa na zakhvat i perevarivanie antigena makrofagami i klirens tushi

Bilateral electrolytic coagulation of the posterior and supraoptic hypothalamic nuclei of rabbits had practically no effect on the engulfment of sheep erythrocytes labeled with radioactive sodium chromate retarding chiefly the rate of the antigen catabolism and promoting its retention in the subcellular fractions of the macrophages function than injury of the anterior one. Coagulation of the supraoptic nucleus accelerated India ink clearance at all the periods of investigation, whereas injury of the posterior hypothalamus failed to influence this process.

Subcellular fractions from dermis and epidermis in contact sensitization of guinea pigs to 1-chloro-2,4-dinitrobenzene.

Subcellular fractions were prepared from the epidermis of guinea pigs which had been painted with 1-chloro-2,4 dinitrobenzene 14 h previously. The microsomal fraction showed less activity than other fractions in the MIF test. Similarly, the microsomal fraction from the dermis of skin irritated with croton oil before DNCB painting was relatively inactive. However, the microsomal fractions from the epidermis and more especially from the dermis of skin painted with DNCB while undergoing allergic contact dermatitis from pentadecylcatechol showed significant MIF activities.