Asbestos exposure induces MCP-1 secretion by pleural mesothelial cells

We showed previously that both crocidolite and chrysotile asbestos inhalation induced a persistent macrophage inflammatory response within the pleural space of the rat. We postulated that the stimulus for pleural macrophage recruitment after asbestos exposure was the induction of monocyte chemoattractant protein-1 (MCP-1) synthesis by pleural mesothelial cells. To test this hypothesis, rat pleural mesothelial cells (RPMC) were cultured with or without chrysotile or crocidolite asbestos fibers (8 micrograms/cm2) in the presence (50 ng/mL) or absence of either tumor necrosis factor-alpha (TNF-alpha) or interleukin-1 beta (IL-1 beta). MCP-1 mRNA expression was assessed by RT-PCR in RPMC cultured for 2 to 24 hours, and MCP-1 protein secretion was measured by ELISA in conditioned medium from 24-hour and 48-hour cultures. Crocidolite and chrysotile fibers induced MCP-1 mRNA expression in RPMC which was maximal after 12 hours in the absence of cytokines, but which peaked after 2 hours when RPMC were challenged with asbestos + TNF-alpha or IL-1 beta. Both types of asbestos also significantly increased MCP-1 protein secretion after 24 and 48 hours (P < .0001), an effect that was potentiated by cytokine stimulation. Rats exposed by inhalation to either chrysotile or crocidolite asbestos fibers also had greater amounts of MCP-1 protein in their pleural lavage fluid than did sham-exposed rats. These findings suggest that MCP-1 secretion by RPMC may have a role in the initiation and/or potentiation of asbestos-induced pleural injury.     

Programmed necrosis induced by asbestos in human mesothelial cells causes high-mobility group box 1 protein release and resultant inflammation

Asbestos carcinogenesis has been linked to the release of cytokines and mutagenic reactive oxygen species (ROS) from inflammatory cells. Asbestos is cytotoxic to human mesothelial cells (HM), which appears counterintuitive for a carcinogen. We show that asbestos-induced HM cell death is a regulated form of necrosis that links to carcinogenesis. Asbestos-exposed HM activate poly(ADP-ribose) polymerase, secrete H₂O₂, deplete ATP, and translocate high-mobility group box 1 protein (HMGB1) from the nucleus to the cytoplasm, and into the extracellular space. The release of HMGB1 induces macrophages to secrete TNF-α, which protects HM from asbestos-induced cell death and triggers a chronic inflammatory response; both favor HM transformation. In both mice and hamsters injected with asbestos, HMGB1 was specifically detected in the nuclei, cytoplasm, and extracellular space of mesothelial and inflammatory cells around asbestos deposits. TNF-α was coexpressed in the same areas. HMGB1 levels in asbestos-exposed individuals were significantly higher than in nonexposed controls (P < 0.0001). Our findings identify the release of HMGB1 as a critical initial step in the pathogenesis of asbestos-related disease, and provide mechanistic links between asbestos-induced cell death, chronic inflammation, and carcinogenesis. Chemopreventive approaches aimed at inhibiting the chronic inflammatory response, and especially blocking HMGB1, may decrease the risk of malignant mesothelioma among asbestos-exposed cohorts.     

Expression of ICAM-1, ICAM-2, NCAM-1 and VCAM-1 by human synovial cells exposed to Borrelia burgdorferi in vitro

The interaction of resident tissue cells with migratory inflammatory cells is essential for the recruitment of immune effector cells to inflammatory sites. The sustained expression of adhesion molecules in the synovium of patients with chronic Lyme arthritis seems to contribute to this chronic inflammation. Whether cell adhesion molecules influence the early steps of Borreliosis is unclear. Therefore, we examined the expression of ICAM-1, ICAM-2, VCAM-1 and NCAM-1 in synovial cells exposed to two different Borrelia burgdorferi sensu stricto strains Geho and B31. The mRNA expression of ICAM-1, ICAM-2, VCAM-1 and NCAM-1 was not changed in synovial cells exposed to B31. Whereas ICAM-2 and VCAM-1 was upregulated, NCAM-1 mRNA was downregulated and ICAM-1 mRNA was unchanged by strain Geho. The ICAM-1 protein expression on the synovial cell surface was downregulated by both strains. Differential regulation of adhesion molecule mRNA, and subsequent high turnover or elevated shedding from the cell membrane may contribute to early pathogenesis in Lyme arthritis.     

Upregulation of the chemokines Rantes, MCP-1, MIP-1a and MIP-2 in early infection with Trypanosoma brucei brucei and inhibition by sympathetic denervation of the spleen

We examined the induction of 4 chemokines during early experimental African trypanosomiasis using in situ hybridization and immunocytochemistry. mRNA expression and protein production of Rantes, MCP-1, MIP-1a and MIP-2 were studied in splenocytes obtained at 0 h, 4 h and 12 h post-infection. Splenic denervation was performed to study the role of the central nervous system in early infection. The mRNA for Rantes increased at 4 h and declined at 12 h, but the protein level was high at both time-points. MCP-1 and MIP-la had elevated mRNA and protein levels at 12 h post-infection. MIP-2 mRNA was high at both 4 h and 12 h, but the protein level was only increased at 12 h. Splenic denervation, but not sham operation, suppressed these responses. The upregulation of these chemokines during very early infection suggests a chemokine role in the developing immunopathology The sympathetic nervous system may, however, participate in modulation of such early immune responses.     

The effects of erythromycin on the viability and the secretion of TNF-alpha and TGF-beta1 and expression of connexin43 by human pleural mesothelial cells

OBJECTIVE: The mechanism by which erythromycin produces pleurodesis remains unknown. The purpose of this study was to investigate the effects of erythromycin on human pleural mesothelial cell (HPMC) viability, the secretion of tumour necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta(1) (TGF-beta(1)) and the level of expression of connexin43. METHODOLOGY: HPMC were incubated with different concentrations of erythromycin. The inhibitory effects of erythromycin on HPMC growth were measured using a tetrazolium-based colorimetric assay. The levels of TNF-alpha and TGF-beta(1) in supernatants were measured by ELISA and levels of connexin43 were assessed by Western blot. RESULTS: Erythromycin injured HPMC in a dose and time-dependent manner. The secretion of both TNF-alpha and TGF-beta(1) by HMPC increased significantly when they were incubated with 100 mg/L erythromycin for 3 or 5 days. The levels of connexin43 in HPMC decreased after incubation with 100 mg/L erythromycin and no relationship was observed between the levels and incubation time. CONCLUSIONS: Erythromycin injures HPMC in a dose- and time-dependent manner and results in the secretion of TNF-alpha and TGF-beta(1). This is one possible mechanism of pleurodesis with erythromycin. Furthermore, erythromycin decreased the levels of connexin43 in HPMC, which could possibly affect the response of HPMC to pleurodesis with erythromycin.     

罗格列酮对高糖诱导大鼠胸主动脉血管平滑肌细胞分泌单核细胞趋化蛋白1的影响及其机制

目的观察不同葡萄糖浓度培养的大鼠胸主动脉平滑肌细胞分泌单核细胞趋化蛋白1（MCP-1）的变化,以及罗格列酮（RGZ）对其分泌的影响。方法用不同浓度的葡萄糖和RGZ单独或联合孵育大鼠胸主动脉平滑肌细胞,用ELISA方法检测培养基中MCP-1的水平,Western Blot方法检测各组所收集细胞胞浆中NF-κBp65和IκBα的表达。结果高葡萄糖浓度培养（11．2,22．4mmol／L）的大鼠胸主动脉平滑肌细胞分泌的MCP-1[分别为（340．87±43．92）pg／ml和（664．87±23．07）pg／m1]明显高于对照组[-（132．20±5．81）pg／ml],RGZ抑制了高葡萄糖孵育下大鼠胸主动脉平滑肌细胞MCP-1蛋白表达水平并呈浓度依赖性,RGZ拮抗剂GW9662（10μmol／L）预处理可部分拮抗其作用。MCP-1水平的变化与细胞浆NF-κB、IκB的表达变化相伴随。结论高糖可以诱导大鼠胸主动脉平滑肌细胞分泌MCP-1,并呈现浓度依赖性;RGZ可抑制高糖诱导的大鼠胸主动脉平滑肌细胞分泌MCP-1水平,上述作用在一定浓度范围内呈现剂量依赖性。高糖诱导平滑肌细胞分泌MCP-1很可能是通过NF-κB通路来调控的。     

二苯乙烯苷对同型半胱氨酸诱导的人脐静脉内皮细胞MCP-1、ICAM-1和VCAM-1表达的影响

目的 观察何首乌二苯乙烯苷对同型半胱氨酸诱导培养的人脐静脉内皮细胞株单核细胞趋化蛋白1(MCP-1)、细胞间黏附分子1(ICAM-1)和血管细胞黏附分子1(VCAM-1) mRNA表达的影响.方法 在人脐静脉内皮细胞的培养基中加入不同浓度的二苯乙烯苷处理2h再加入3.0 mmol/L同型半胱氨酸作用36 h.Hoechst33342核染色检测细胞核损伤;以RT-qPCR检测不同浓度二苯乙烯苷处理对同型半胱氨酸诱导的人脐静脉内皮细胞MCP-1、ICAM-1及VCAM-1 mRNA表达的影响.结果 10 μmol/L浓度以内,二苯乙烯苷预孵育呈浓度依赖性降低3.0 mmol/L同型半胱氨酸所致人脐静脉内皮细胞核损伤加重,抑制同型半胱氨酸所致MCP-1、ICAM-1及VCAM-1 mRNA的表达升高(P＜0.05或P＜0.01).结论 二苯乙烯苷具有明显抑制同型半胱氨酸所致人脐静脉内皮细胞MCP-1、ICAM-1、VCAM-1 mRNA表达增加的作用.     

氧化低密度脂蛋白对大鼠树突状细胞趋化因子分泌及趋化因子受体表达的影响

目的:探讨氧化低密度脂蛋白(oxLDL)对SD大鼠骨髓源树突状细胞(DCs)趋化因子巨噬细胞炎性蛋白(MIP)-1a和单核细胞趋化蛋白(MCP)-1分泌及趋化因子受体(CCR)5和CCR7表达的影响.方法:将SD大鼠骨髓源DCs为研究对象,以PBS作阴性对照,分别与10和50 mg/L的oxLDL混合培养48 h后,动态观察DCs成熟过程中的形态学变化,酶联免疫吸附试验检测细胞培养上清趋化因子MIP-1a和MCP、1,荧光定量RT-PCR检测DCs细胞趋化因子受体CCR5和CCR7浓度的表达.结果:oxLDL可促进SD大鼠骨髓源DCs上清MCP-1的表达(P＜0.05),并可以明显促进细胞表达CcR7(P＜0.01).结论:oxLDL可促进DCS成熟,增加DCs分泌MCP-1,并上调CCR7的表达,DCs迁徙变化可能参与动脉粥样硬化的形成.     

辛伐他汀抑制P38MAPK信号通路减少大鼠肾小球系膜细胞MCP-1及ICAM-1表达的研究

目的探讨P38促分裂原活化蛋白激酶（P38MAPK）信号通路在糖尿病肾病（DN）中的作用及辛伐他汀（SI）在防治DN中的作用机制。方法分别以高糖、糖基化终产物（AGE）或过氧化氢体外孵育大鼠肾小球系膜细胞（MC）,检测P38MAPK和单核细胞趋化蛋白1（MCP-1）及细胞间黏附因子1（ICAM-1）在MC的表达。比较有无P38MAPK特异性抑制剂SB203580（SB）或辛伐他汀（SI）预处理时以上3种因素对P38MAPK和MCP-1及ICAM-1在MC表达的影响。结果高糖、AGE或H2O2均可独立激活P38MAPK,并增加MCP-1及ICAM-1在MC的表达;SB显著抑制MCP-1及ICAM-1的表达;SI抑制P38MAPK的活化并减少MCP-1及ICAM-1的表达。结论P38MAPK是MCP-1及ICAM-1的上游信号分子,表明P38MAPK可能是DN发生的始动信号之一。SI可能通过抑制P38MAPK磷酸化而抑制MCP-1及ICAM-1的表达,有防治DN的作用。     

Human endothelial cells express CCR2 and respond to MCP-1: direct role of MCP-1 in angiogenesis and tumor progression

Although several CXC chemokines have been shown to induce angiogenesis and play roles in tumor growth, to date, no member of the CC chemokine family has been reported to play a direct role in angiogenesis. Here we report that the CC chemokine, monocyte chemotactic protein 1 (MCP-1), induced chemotaxis of human endothelial cells at nanomolar concentrations. This chemotactic response was inhibited by a monoclonal antibody to MCP-1. MCP-1 also induced the formation of blood vessels in vivo as assessed by the chick chorioallantoic membrane and the matrigel plug assays. As expected, the angiogenic response induced by MCP-1 was accompanied by an inflammatory response. With the use of a rat aortic sprouting assay in the absence of leukocytic infiltrates, we ruled out the possibility that the angiogenic effect of MCP-1 depended on leukocyte products. Moreover, the direct effect of MCP-1 on angiogenesis was consistent with the expression of CCR2, the receptor for MCP-1, on endothelial cells. Assessment of supernatant from a human breast carcinoma cell line demonstrated the production of MCP-1. Treatment of immunodeficient mice bearing human breast carcinoma cells with a neutralizing antibody to MCP-1 resulted in significant increases in survival and inhibition of the growth of lung micrometastases. Taken together, our data indicate that MCP-1 can act as a direct mediator of angiogenesis. As a chemokine that is abundantly produced by some tumors, it can also directly contribute to tumor progression. Therefore, therapy employing antagonists of MCP-1 in combination with other inhibitors of angiogenesis may achieve more comprehensive inhibition of tumor growth.     

Limited expression of R5-tropic HIV-1 in CCR5-positive type 1-polarized T cells explained by their ability to produce RANTES, MIP-1alpha, and MIP-1beta

Human T helper (Th) cells (Th1- or Th2-oriented memory T cells as well as Th1- or Th2-polarized naive T cells) were infected in vitro with an R5-tropic HIV-1 strain (BaL) and assessed for their profile of cytokine production, CCR5 receptor expression, and HIV-1 p24 antigen (p24 Ag) production. Higher p24 Ag production was found in CCR5-negative Th2-like memory T cells than in CCR5-positive Th1-like memory T cells. By contrast, p24 Ag production was higher in Th1-polarized activated naive T cells in the first 4 days after infection. However, p24 Ag production in Th1-polarized T cells became comparable or even lower than the production in Th2-polarized populations later in infection or when the cells were infected with HIV-1BaL after secondary stimulation. The higher levels of p24 Ag production by Th1-polarized naive T cells soon after infection reflected a higher virus entry, as assessed by the single round infection assay using the HIV-chloramphenicol acetyl transferase (HIV-CAT) R5-tropic virus that contains the envelope protein of HIV-1 YU2 strain. The limitation of viral spread in the Th1-polarized populations, despite the initial higher level of T-cell entry of R5-tropic strains, was due to the ability of Th1 cells to produce greater amounts of beta-chemokines than Th2 cells. In fact, an inverse correlation was observed between Th1-polarized naive T cells and Th1-like memory-activated T cells in regards to p24 Ag production and the release of the following CCR5-binding chemokines: regulated on activation normal T expressed and secreted (RANTES), macrophage inflammatory protein-1alpha (MIP-1alpha), and MIP-1beta. Moreover, infection with the HIV-1BaL strain of Th1-polarized T cells in the presence of a mixture of anti-RANTES, anti-MIP-1alpha, and anti-MIP-1beta neutralizing antibodies resulted in a significant increase of HIV-1 expression. These findings suggest that Th1-type responses may favor CD4(+) T-cell infection by R5-tropic HIV-1 strains, but HIV-1 spread in Th1 cells is limited by their ability to produce CCR5-binding chemokines. (Blood. 2000;95:1167-1174)     

Angiopoietin-1 reduces VEGF-stimulated leukocyte adhesion to endothelial cells by reducing ICAM-1, VCAM-1, and E-selectin expression

Vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang1) are potent vasculogenic and angiogenic factors that hold promise as a means to produce therapeutic vascularization and angiogenesis. However, VEGF also acts as a proinflammatory cytokine by inducing adhesion molecules that bind leukocytes to endothelial cells, an initial and essential step toward inflammation. In the present study, we used human umbilical vascular endothelial cells (HUVECs) to examine the effect of Ang1 on VEGF-induced expression of three adhesion molecules: intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin. Interestingly, Ang1 suppressed VEGF-induced expression of these adhesion molecules. Furthermore, Ang1 reduced VEGF-induced leukocyte adhesion to HUVECs. These results demonstrate that Ang1 counteracts VEGF-induced inflammation by reducing VEGF-induced endothelial adhesiveness.     

Proliferation of rat and human lung fibroblasts following exposure to prostaglandin E2

Numerous investigators have reported that exogenous prostaglandin E2 (PGE2) can inhibit human lung fibroblast proliferation in vitro. Yet various lines of evidence derived from clinical and experimental studies suggest that PGE2 may not be of major importance in inhibiting fibroblast proliferation in vivo. We examined the effects of exogenously-supplied PGE2 on the in vitro proliferation of HFL-1 human lung fibroblasts and rat lung fibroblasts derived from Fischer 344 rats using a multisample assay system that provided a detailed kinetic picture of PGE2 effects on fibroblast proliferation. Exogenously supplied PGE2 (5-5000 ng/ml) had no effect on the proliferation of actively cycling or initially quiescent subconfluent populations of rat lung fibroblasts. In contrast, initially quiescent subconfluent or confluent cultures of HFL-1 cells that were treated with 50-5000 ng/ml PGE2 exhibited a dose-dependent, transitory inhibition of division when stimulated to return to a state of active proliferation. Once division resumed, the cells divided at the rate of the PGE2-free control condition, even in the continued presence of the prostaglandin. This initial postinhibitory resumption of division was not attributable to the emergence of a PGE2-resistant subpopulation. Thus, although exogenously supplied PGE2 indeed inhibits proliferation of human pulmonary fibroblasts in vitro, the duration of the inhibition appears to be much shorter than previously suspected.     

红霉素对人胸膜间皮细胞肿瘤坏死因子α、转化生长因子β1分泌和缝隙连接蛋白43表达的影响

目的 研究红霉素刺激下对人胸膜间皮细胞分泌肿瘤坏死因子α(TNF-α)、转化生长因子β1(TGF-β1)和缝隙连接蛋白43(connexin 43)表达的影响，探讨胸膜粘连机制。方法 通过体外培养人胸膜间皮细胞(HPMC)，采用ELISA法测定不同浓度红霉素刺激下培养上清液TNF-α、TGF-β1浓度变化；Western印迹法测定红霉素对HPMC的缝隙连接蛋白43水平的影响。结果 100mg／L的红霉素与HPMC一起孵育3或5d后可引起HPMC分泌的TNF-α增多；不同浓度红霉素和孵育时间下HPMC分泌TGF-β1明显升高；100mg／L红霉素刺激下HPMC的缝隙连接蛋白43的水平下降，与作用的时间长短无关。结论 红霉素能够刺激HPMC分泌TNF-α和TGF-β1，可能是红霉素胸膜固定术的作用机制之一。红霉素改变HPMC的缝隙连接蛋白43水平，可能是HPMC对刺激的反应和功能调节。本实验的各项观察指标多在较高浓度的红霉素刺激下发生变化，提示临床上应用红霉素作胸膜粘连应以浓度较高的溶液为宜。     

Glycoprotein, elastin, and collagen secretion by rat smooth muscle cells.

Smooth muscle cells from rat heart secreted extracellular matrix components at high rates for many generations in culture. The matrix proteins remained anchored to the culture dish and were characterized after removal of cellular material with sodium dodecyl sulfate. Sequential enzyme digestion demonstrated the presence of at least three components, including glycoprotein(s), elastin, and collagen. Prolonged extraction of the matrix with detergent under reducing conditions solubilized a fucosylated glycoprotein having an apparent molecular weight of 250,000 and two other proteins with molecular weights of 72,000 and 45,000, respectively. Sublines derived from discrete colonies of smooth muscle cells synthesized all of the matrix components, and the proportion of collagen secreted by some sublines increased with time in culture. The biosynthesis of a mixed extracellular matrix and the relationships among the component proteins were therefore studied in one system producing milligram quantities of material.     

Hormonal regulation of protein synthesis, secretion, and phosphorylation in cultured rat Sertoli cells.

The accumulation of two polypeptides, SCm1 and SCm2, in the medium of Sertoli cell cultures is enhanced by follicle-stimulating hormone (FSH) but is unaffected by either the cAMP analog, N6,O2'-dibutyrl cAMP or luteinizing hormone. The assigned molecular weights of SCm1 and SCm2 differ from those of androgen-binding protein subunits or any other previously identified Sertoli cell secretory product. Incubation of Sertoli cell cultures with either FSH or N6,O2'-dibutyryl cAMP also stimulates the incorporation of [35S]methionine into two intracellular polypeptides, SCc1 and SCc2. In addition, the phosphorylation of three intracellular polypeptides, SCc3, SCc4, and SCc5, is intensified when Sertoli cell cultures are treated with either FSH or N6,O2'-dibutyryl cAMP. Based on these results and on previous work, we conclude that (i) SCm1 and SCm2 may, like androgen-binding protein, be secreted by Sertoli cells and function extracellularly while SCc1 and SCc2 are involved in FSH-dependent intracellular activity; (ii) SCc3, SCc4, and SCc5 are possible substrates for FSH-stimulated, cAMP-dependent protein kinase activity; and (iii) SCc5 is an isoelectric variant of vimentin-type intermediate filament protein presumably involved in FSH- and N6,O2'-dibutyryl cAMP-induced Sertoli cell shape changes.     

Synthesis and secretion of glucagon-like peptide-1 by fetal rat intestinal cells in culture

Secretion of the intestinal proglucagon-derived peptides (PGDPs) including the incretin glucagon-like peptide-1 (GLP-1) is regulated, at least in part, by the duodenal hormone glucose-dependent insulinotropic peptide (GIP) through a protein kinase (PK) A-dependent pathway. It has been demonstrated that the activation of PKA increases the synthesis of some intestinal PGDPs, particularly the glucagon-like immunoreactive (GLI) peptides glicentin and oxyntomodulin. However, the effects of GIP on GLI and GLP-1 synthesis are not known. Fetal rat intestinal cells in culture were therefore treated for up to 24 h with 5mm dbcAMP or 10⁻⁶ m GIP and the changes in glicentin, oxyntomodulin, GLP-1^x-37 and GLP-1^x-36NH2 secretion and synthesis were examined by RIA and HPLC. Both dbcAMP and GIP increased the acute (2 h; to 224±21 and 256±20% of controls, respectively,P<0.001) and chronic (24 h; to 230±22 and 130±6% of controls, respectively,P<0.001) secretion of intestinal PGDPs. In contrast, the total culture content of PGDPs was increased only after 24 h of incubation (to 156±15 and 125±7% of controls for dbcAMP and GIP, respectively,P<0.01). HPLC analysis confirmed that the intestinal cultures produced the GLI peptides glicentin and oxyntomodulin, as well as the biologically active forms of GLP-1, GLP-7^7–37 and GLP-1^7-36NH2. The relative proportion of these peptides was not altered by treatment with dbcAMP or GIP. Thus, in addition to its effects on GLP-1 release from the rat intestine, GIP appears to be an important regulator of the synthesis of this insulinotropic peptide.     

Monocyte chemoattractant protein 1 (MCP-1) released from Helicobacter pylori stimulated gastric epithelial cells induces cyclooxygenase 2 expression and activation in T cells

BACKGROUND: and aims: To clarify the interaction between gastric epithelial and mucosal T cells, we examined the role of cytokines released from epithelial cells in response to Helicobacter pylori water extract protein (HPWEP) in regulating T cell cyclooxygenase 2 (COX-2) expression and activation. METHODS: Media from MKN-28 cells incubated with HPWEP for 48 hours were added to Jurkat T cells and human peripheral T cells. C-C and CXC chemokine concentrations in MKN-28 cell media, and COX-2 expression, interferon gamma (IFN-gamma), and interleukin (IL)-4 secretions in T cells were determined by western blot analysis and ELISA methods. Distributions of COX-2 positive T cells and monocyte chemoattractant protein 1 (MCP-1) in tissue specimens with H pylori associated gastritis were determined as single or double labelling by immunohistochemistry. RESULTS: MCP-1, IL-7, IL-8, and RANTES were detected in media from MKN-28 cells incubated with HPWEP. Media as a whole, and MCP-1 alone, stimulated COX-2 expression and peripheral T cell proliferation. Anti-MCP-1 antibody inhibited media stimulated COX-2 mRNA expression in Jurkat T cells. Media stimulated IFN-gamma but not IL-4 secretion from peripheral T cells, while MCP-1 stimulated IL-4 but not IFN-gamma secretion. Both stimulated cytokine release, and peripheral T cell proliferation was partially inhibited by NS-398, a specific COX-2 inhibitor. In mucosa with gastritis, COX-2 was expressed in T cells and MCP-1 was localised mainly in epithelial and mononuclear cells. MCP-1 levels and the intensity of COX-2 expression in tissue samples were closely related. CONCLUSIONS: Cytokines such as MCP-1, released from gastric epithelial cells in response to HPWEP, seem to modulate T cell immune responses, at least in part via COX-2 expression.     

RANTES and MIP-1alpha production by T lymphocytes, monocytes and NK cells from nonagenarian subjects.

While numerous previous studies have investigated age-related changes of cytokine production, little is known about chemokines, the importance of which in regulating immune response is becoming increasingly evident. In this study, a group of healthy subjects over 90 years old is compared to a group of young subjects, we evaluated the ability of monocytes, T lymphocytes and NK cells: (1) to produce RANTES and MIP-1alpha, either in basal conditions or after stimulation with, respectively, LPS, anti-CD3 MoAb and IL-2; (2) to express the corresponding chemokine receptors (CCR1, CCR3, CCR5). We demonstrate that: (a) monocytes, T lymphocytes and NK cells spontaneously produced detectable amounts of chemokines, both in young and old subjects; (b) monocyte-dependent RANTES and MIP-1alpha production induced by LPS was up-regulated in nonagenarian subjects as anti-CD3-induced secretion from T cells; (c) RANTES and MIP-1alpha production by IL-2 stimulated NK cells was reduced in elderly subjects; (d) CCR1, CCR3 and CCR5 were widely expressed on monocytes, but less expressed on T lymphocytes and NK cells. The diversity within PBMC might reflect their different states of activation and/or responsiveness, influencing the ability to develop rapid innate and long-lasting adaptive immune responses.