TNF polymorphism and bronchoalveolar lavage cell TNF-alpha levels in chronic beryllium disease and beryllium sensitization

BACKGROUND: Beryllium stimulates TNF-alpha from chronic beryllium disease (CBD) bronchoalveolar lavage (BAL) cells. OBJECTIVE: We sought to relate TNF polymorphisms to beryllium-stimulated TNF-alpha production, to the development of CBD, and to the risk of more severe CBD over time. METHODS: We recruited 147 patients with CBD, 112 beryllium-sensitized subjects, and 323 control subjects; genotyped 5 TNF promoter polymorphisms; and measured beryllium-stimulated and unstimulated BAL cell TNF-alpha production from a subset of subjects. RESULTS: Beryllium-stimulated, but not beryllium-unstimulated, BAL cell TNF-alpha production was significantly increased in patients with CBD compared with that seen in those only sensitized (P = .0002). Those subjects with the TNF -857T allele and the only haplotype (haplotype 4) containing this allele demonstrated significantly lower unstimulated BAL cell TNF-alpha production compared with that seen in noncarriers (P = .009). Patients with CBD alone and combined with sensitized subjects carrying the TNF haplotype 1 compared with those without this haplotype had significantly increased beryllium-stimulated BAL cell TNF-alpha levels (P = .02). We found no significant association between patients with CBD, sensitized subjects, and control subjects with any of the TNF promoter polymorphisms or haplotypes. A greater decrease in Pao(2) at maximum exercise was noted in patients with CBD with the -1031C allele (P = .03) and with haplotypes other than the TNF haplotype 1 (P = .01), 3 (from 5) of which contain the -1031C allele. CONCLUSIONS: The -857T allele and haplotype 1 are associated with BAL cell TNF-alpha production, indicating a potential role of TNF promoter variants in regulation of TNF production in sensitized subjects and patients with CBD. CLINICAL IMPLICATIONS: TNF promoter variants are not risk factors for CBD or sensitization.     

Immunology of chronic beryllium disease

PURPOSE OF REVIEW: This review discusses the immunology of chronic beryllium disease. It addresses the importance of the interaction between class II molecules and the T cells that recognize beryllium, along with the subsequent immune response that results in sensitization and disease, and genetic factors leading to variation in this response. RECENT FINDINGS: HLA-DPB1 with a glutamic acid at amino acid position 69 (Glu69) confers increased risk of beryllium sensitization and is not specific for chronic beryllium disease. The degree of negative surface charge of the molecule may increase risk of chronic beryllium disease but not sensitization. In the absence of Glu69, HLA-DRB1 alleles may function in beryllium presentation, increasing the risk of chronic beryllium disease. The T-cell response as assessed by the beryllium lymphocyte proliferation test is dependent on central memory T-cells, while Th1 cytokine secretion leading to granulomatous inflammation and chronic beryllium disease is dependent on the activity of effector memory T cells. Polymorphisms in cytokine genes, such as the TGF-beta1 gene, also affect the risk of chronic beryllium disease and more severe disease. SUMMARY: The current diagnostic criteria for sensitization and chronic beryllium disease rely on the beryllium lymphocyte proliferation test. By understanding the novel immunologic mechanisms and genetic factors associated with sensitization and chronic beryllium disease, we may improve our ability to detect beryllium health effects with new diagnostics, and hopefully refine therapies for disease.     

T cell recognition in chronic beryllium disease

Chronic beryllium disease (CBD) is a granulomatous lung disorder caused by beryllium exposure in the workplace and is characterized by the accumulation of beryllium-specific CD4(+) T cells. Depending on genetic susceptibility and the nature of the exposure, CBD occurs in up to 20% of exposed workers. Genetic susceptibility has been associated with particular HLA-DP alleles, especially those possessing a negatively charged glutamic acid residue at the 69th position of the beta-chain. The mechanism for this association lies in the ability of these HLA-DP molecules to bind and present beryllium to pathogenic CD4(+) T cells. Large numbers of effector memory, beryllium-specific CD4(+) T cells are recruited to the lung of these subjects and secrete Th1-type cytokines upon beryllium recognition. The presence of circulating beryllium-specific CD4(+) T cells directly correlates with the severity of lymphocytic alveolitis. With the presence of a known antigenic stimulus, CBD serves as an important model of immune-mediated, organ destruction. Thus, our findings in CBD have important implications for studies in autoimmune diseases, in particular those with an unknown inciting antigen and an inaccessible target organ.     

Beryllium-ferritin: lymphocyte proliferation and macrophage apoptosis in chronic beryllium disease

A beryllium (Be)-ferritin adduct containing 270 pm of Be stimulated proliferation of bronchoalveolar lavage (BAL) lymphocytes from subjects with chronic beryllium disease (CBD) at concentrations 5-6 logs lower than the amounts of beryllium sulfate (BeSO4) needed to induce proliferation. We observed increased apoptotic CBD BAL macrophages after exposure to both BeSO4 (50 +/- 6%, mean +/- SEM, P <0.05 versus unstimulated controls) and Be-ferritin (40 +/- 2%), whereas only 2.0 +/- 0.2% of BAL lymphocytes underwent activation-induced cell death. Be-ferritin also induced apoptosis in BAL macrophages from subjects with Be sensitization (25 +/- 3%) and in the H36.12j hybrid macrophage cell line (15 +/- 2%). Be-ferritin induced lung macrophage CD95 (Fas) expression and the activation of intracellular caspase-3, -8 and -9. Thus, lung macrophages take up Be-ferritin, delivering physiologically relevant levels of Be that promote Be antigen presentation and macrophage apoptosis. Be-ferritin thereby serves as a "Trojan Horse," triggering proliferation of Be-ferritin-specific CBD BAL T cells. We hypothesize that Be-ferritin exposure may result in persistent antigen exposure inducing Be-specific T cell clonal expansion and T cell helper type 1-type cytokine production and potentially explains the chronicity of CBD and its development years after environmental Be exposure has ceased.     

TNF-alpha G-308A polymorphism is associated with rheumatic fever and correlates with increased TNF-alpha production

Previous studies suggested that abnormal regulation of TNF-alpha production may have a role in the pathogenesis of rheumatic fever (RF). Polymorphism at the promoter region of TNF-alpha gene (-308 A) has recently been shown to be associated with rheumatic heart disease (RHD) in Mexican patients. Although this polymorphism has long been shown to affect TNF-alpha gene expression in cell lines, its role in production of the cytokine in RF patients has not been studied. We therefore investigated TNF-alpha G-308A single nucleotide polymorphism and its effect on TNF-alpha production in 71 Turkish RF patients and 89 ethnically matched healthy controls. The TNF-alpha-308A allele frequency was found to be significantly higher in RF patients (RHD+arthritis) than in healthy controls [p<0.0032 Odds ratio (OR)=3.4, 95% confidence interval (CI) (1.5-7.7)]. When RHD patients were analyzed as a separate group, significant difference persisted [p<0.0055, OR=3.3, 95% CI (1.5-7.6)]. More importantly, ELISPOT analysis demonstrated that existence of A allele was associated with higher TNF-alpha production compared with G allele. Our data suggest that carrying a high responder TNF-alpha-308A allele may be a genetic factor in increasing the susceptibility to develop RF disease.     

TNF-alpha and growth hormone resistance in patients with chronic liver disease.

Liver cirrhosis is characterized by a severe impairment of the growth hormone/insulin-like growth factor-1 (GH-IGF-1) axis, that is, acquired GH resistance. The condition of the GH-IGF-1 axis in the phase of chronic liver disease (CLD) preceding cirrhosis, however, remains uncertain. The origin of GH resistance during CLD is multifactorial, and to date, the liver functional mass is considered to play a major role. Although proinflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and IL-1beta, were found to be elevated in patients with CLD and were shown to induce a state of GH resistance in other disease models, their involvement in the pathogenesis of GH resistance during CLD has never been investigated. We characterized the GH-IGF-1 axis by analyzing the individual components of the axis (GH, IGF-1, IGF-binding protein-3 [IGFBP-3], acid-labile subunit [ALS]) and the corresponding ratios (GH/IGF-1, GH/IGFBP-3, and GH/ALS) and verified the links with circulating proinflammatory cytokines (TNF-alpha, IL-1beta, and IL-6), in 34 patients with CLD and 12 healthy controls. Evolution of CLD from chronic hepatitis (CH, n = 17) to cirrhosis (CIR, n = 17) was associated with a progressive increase of GH resistance indices (e.g., GH/IGF-1 ratio: controls 0.5 +/- 0.9, CH 15.9 +/- 31.2, p < 0.01 vs. controls; CIR 188.4 +/- 282.7 mU/nmol, p < 0.001 vs. CH and controls), indicating its onset also in the early stages of CLD. The progressive increase in GH resistance indices matched the increase of circulatory TNF-alpha (e.g., TNF-alpha vs. GH/IGF-1, r = 0.54, p < 0.001). A similar trend was found for IL-6 without reaching statistical significance (r = 0.23, p = 0.13). We found undetectable levels of IL-1beta in our sample of patients and controls. We conclude that proinflammatory cytokines play an important role in the pathogenesis of GH resistance in CLD, but TNF-alpha is a major factor. In addition, GH resistance is present in CLD from the early stages. These results could begin new therapeutic lines of attack in the management of CLD.     

Maintenance of alveolitis in patients with chronic beryllium disease by beryllium-specific helper T cells

Chronic beryllium disease is characterized by the accumulation of helper/inducer T cells, macrophages, and granulomas in the lungs. To evaluate the hypothesis that the proliferation of CD4+ (helper/inducer) T cells in the lungs of patients with this disorder is maintained by local activation of beryllium-specific T-cell clones, we studied T cells obtained from peripheral blood and by bronchoalveolar lavage in eight patients and five healthy controls. The proliferation of T cells in response to beryllium in vitro was confined to the CD4+ T cells from the patients and was dependent on the presentation of antigen in the presence of both major histocompatibility complex class II antigens and functional interleukin-2 receptors. T cells from the patients' lungs had a significantly greater response to beryllium than did T cells from their peripheral blood (stimulation index, 103 vs. 5; P less than 0.01). Lines and clones of cells developed from T cells from the patients' lungs showed dose-dependent proliferation in response to beryllium but did not respond to recall antigens or to other metals. Although all beryllium-specific T-cell clones were CD4+ and none were CD8+ (suppressor/cytotoxic), all beryllium-specific clones studied had different rearrangements of T-cell antigen receptors, suggesting that the response to beryllium involved T cells with diverse specificities for beryllium. We conclude that in patients with chronic beryllium disease, beryllium acts as a class II-restricted antigen, stimulating local proliferation and accumulation in the lung of beryllium-specific CD4+ (helper/inducer) T cells. Hence, chronic beryllium disease is a hypersensitivity disease in which beryllium is the specific antigen.     

Reexamination of the blood lymphocyte transformation test in the diagnosis of chronic beryllium disease

The T cell response to beryllium, measured in bronchoalveolar lavage by the lymphocyte transformation test (LTT), is a critical diagnostic test for discriminating between chronic beryllium disease (CBD) and other granulomatous diseases. We examined the sensitivity, reproducibility, and methods of a less invasive, peripheral blood LTT in 17 patients with CBD and in 18 beryllium-exposed control subjects. Ninety-four percent of CBD cases (16/17) had abnormal blood LTT results, and all 18 beryllium-exposed control subjects had normal blood LTT results. Split samples for 10 beryllium disease cases and eight control subjects demonstrated that the blood LTT was reproducible between two separate laboratories. The LTT was equally sensitive with 10% and 20% serum in the culture medium. We conclude that an abnormal blood LTT can be used to diagnose CBD in patients with compatible lung pathology.     

Self-presentation of beryllium by BAL CD4+ T cells: T cell-T cell interactions and their potential role in chronic beryllium disease

Chronic beryllium disease (CBD) is characterized pathologically by granulomatous inflammation in the lung, composed of a large core of epithelioid cells surrounded by a dense shell of CD4+ T cells. Using beryllium-specific CD4+ T cell lines derived from the bronchoalveolar lavage (BAL) fluid of CBD patients, we show that purified CD4+ T cells produced significant amounts of IFN-gamma and TNF-alpha upon exposure to beryllium in the absence of antigen-presenting cells (APC). However, unlike BAL T cells stimulated by beryllium in the presence of APC, self-presentation by BAL T cells did not induce detectable IL-2 production, and in its absence these activated T cells die from programmed cell death. Resting BAL CD4+ T cells constitutively express high levels of HLA-DP, lymphocyte function-associated antigen 1 (LFA-1) and ICAM-3. When stimulated with beryllium/APC, the adhesion molecule ICAM-1 was up-regulated, as well as several costimulation molecules including CD28, OX-40 (CD134), 4-1-BB (CD137) and B7-1 (CD80). Notably, CD28 was not up-regulated during self-presentation by BAL T cells, and these cells do not express OX-40L, suggesting that lack of appropriate costimulation was responsible for programmed cell death observed upon beryllium self-presentation. Restricting anti-MHC class II mAb completely eliminated beryllium-induced T cell proliferation during self-presentation and significantly reduced IFN-gamma and TNF-alpha production. Our data demonstrate for the first time that self-presentation by BAL T cells in response to beryllium can occur ex vivo, in the absence of professional APC, with a specific dependence on T cell-expressed MHC class II molecules and exogenous IL-2 for survival.     

Anti-apoptosis function of TNF-alpha in chronic lymphocytic leukemia: lessons from Crohn's disease and the therapeutic potential of bupropion to lower TNF-alpha

Crohn's disease and B cell chronic lymphocytic leukemia (CLL) share a common link in their pathologic mechanisms. Lymphocytes in both diseases fail to undergo apoptosis and die properly. That failure is partly due to increased signaling by tumor necrosis factor (TNF)-alpha, and their respective pathologies directly follow from this apoptosis failure. Bupropion is a commonly used generic antidepressant in clinical use for over a decade, and early evidence indicates it lowers TNF levels. This paper suggests the use of bupropion in CLL to lower TNF levels, which may thereby slow CLL disease course.     

BTNL2 allele associations with chronic beryllium disease in HLA-DPB1*Glu69-negative individuals

Butyrophilin-like 2 (BTNL2) polymorphisms have been associated with sarcoidosis. We hypothesized that BTNL2 variants might confer a human leukocyte antigen (HLA)-independent risk for chronic beryllium disease (CBD), a granulomatous lung disease with similar clinical, radiological, and pathological features to sarcoidosis. Genomic DNA was obtained from CBD (n= 88), beryllium sensitized (BeS, n= 86), and beryllium exposed nondiseased control subjects (Be-exp, n= 173). Six BTNL2 polymorphisms, HLA-DPB1, DRB1, and DQB1 alleles were determined by sequence-specific primer-PCR. All BTNL2 polymorphisms were in Hardy-Weinberg equilibrium. No significant differences were found between BTNL2 polymorphisms or haplotypes and CBD, BeS, or Be-exp. In HLA-DPB1*Glu69-negative subjects (n= 10 CBD, n= 13 BeS, n= 102 Be-exp), DRB1*13 and BTNL2 rs3117099TT homozygosity were increased in CBD (70% and 40%, respectively) vs Be-exp (16%, P= 0.001 and 2.9%, P= 0.001, respectively). The BTNL2 rs3117099T-HLA-DRB1*13 combination was significantly increased in CBD (50%) compared with Be-exp (6.9%, P= 0.001). In conclusion, both DRB1*13 and rs3117099TT homozygosity are associated with CBD in *Glu69-negative subjects, while DPB1*Glu69 is associated with CBD and BeS compared with Be-exp. As a result of the small sample size and strong linkage disequilibrium between DRB1*13-DQB1*0603/4/9 and the BTNL2 rs3117099T allele, it is difficult to assess the primary association in DPB1*Glu69-negative CBD cases.     

Association of TNF-alpha polymorphisms in Crohn disease

Clinical and molecular studies implicate tumor necrosis factor alpha (TNF-alpha) as a key mediator in the initiation and propagation of Crohn disease (CD). Genetic associations have been documented between promoter polymorphisms of TNF-alpha and CD; however, these associations have not been universally replicated. In this study, we set out to examine the association of five promoter TNF-alpha polymorphisms in CD subjects from a founder population. In total, 128 CD subjects and 103 ethnically matched healthy controls were genotyped with time-of-flight mass spectrometry for the following five single nucleotide polymorphisms (SNPs) in the 5' flanking region of TNF-alpha gene: -1031 (T-->C), -863 (C-->A), -857 (C-->T), -308 (G-->A), and -238 (G-->A). Primer sequences, termination mixes, and multiplexing were determined with Sequenom SpectroDESIGNER software v1.3.4. The minor allele frequency for the TNF-alpha SNPs in subjects with CD and healthy controls, respectively, were -238 (5.5% vs. 5.3%); -308 (17.6% vs. 18.9%); -857 (5.1% vs. 7.8%); -863 (19.1% vs. 17.5%), and -1031 (24.6% vs. 22.8%). Thus, none of the TNF-alpha variants was associated with CD. Furthermore, no genotype/phenotype correlations were observed for the mutant allele of the TNF-alpha variants and selected clinical outcomes. In conclusion, there was no significant association for any of the TNF-alpha promoter polymorphism tested and CD in the Newfoundland population.     

Elevated monocytic IL-12 and TNF-alpha production in Wegener's granulomatosis is normalized by cyclophosphamide and corticosteroid therapy

Wegener's granulomatosis (WG) is characterized by a predominance of the type 1 T-helper cell (Th1) response. We have studied monocytic cytokine expression in untreated patients and in patients who did not respond to prior methotrexate or trimethoprim-sulphamethoxazole therapy, i.e. patients with active disease. Intracytoplasmic IL-12 and TNF-alpha expression was significantly increased in WG compared with healthy controls. IL-8 expression was not increased. Two and 12 weeks of daily standard oral cyclophosphamide and corticosteroid (CYC + GC) treatment induced a stable remission of the disease. Elevated IL-12 and TNF-alpha expression of monocytes was normalized. The active metabolite of CYC was shown to down-regulate IL-12 mRNA in vitro. Monocytic cytokines, especially IL-12, may have a role in the early determination and skewing of the immunoregulatory response towards a Th1 profile. It appears that CYC + GC exerts its effect by normalizing the Th1-driving cytokine pattern, and CYC may maintain this mode of action. Normalization of the skewed cytokine pattern may be a prerequisite and an indicator of inducing a remission in WG.     

Serum concentration of gammaGT is a surrogate marker of hepatic TNF-alpha mRNA expression in chronic hepatitis C

Serum gammaGT levels and hepatic expression of tumor necrosis factor-alpha (TNF-alpha) are host factors that can independently predict the outcome of interferon (IFN) treatment in patients with chronic hepatitis C virus (HCV) infection. To explore whether a correlation exists between these two factors, we measured pretreatment gammaGT levels in serum and TNF-alpha mRNA levels in liver biopsies of chronic HCV patients. Seventy-two HCV patients treated with 3-to-5 million units of IFN-alpha three times a week were enrolled in the study. Treatment lasted 24 weeks and was followed by a 48-week follow-up period. Efficacy was assessed by measuring HCV RNA and alanine aminotransferase by the end of follow-up. Twelve patients (16.6%) showed a sustained biochemical and virological response. Normal pretreatment gammaGT levels, low HCV RNA titer, and infection with genotype other than HCV-1 were shown to be independent predictors of sustained response. Hepatic levels of TNF-alpha mRNA, quantified by polymerase chain reaction, were significantly higher in nonresponders (3.44 arbitrary units) compared to sustained responders (1.84 arbitrary units; P = 0.009). Values 相似文献   

Normal pressure hydrocephalus triggers intrathecal production of TNF-alpha

Normal pressure hydrocephalus (NPH) is associated with periventricular white matter lesions and demyelination. The aim of the present study was to examine the cerebrospinal fluid (CSF) levels of tumor necrosis factor-alpha (TNF-alpha), a proinflammatory cytokine mediating myelin damage, in patients with NPH. TNF-alpha levels were analyzed by ELISA and measured before and after shunt operation in 35 patients with NPH. The levels of this cytokine were related to the symptomatology and to magnetic resonance imaging (MRI) verified white matter lesions. They were also related to intrathecal levels of sulfatide, a marker for white matter degradation and to levels of neurofilament, a marker for neuronal degeneration.The preoperative levels of TNF-alpha were increased in the CSF of NPH patients compared to controls, and correlated to the levels of sulfatide. The intrathecal TNF-alpha levels were higher in NPH patients with impairment of wakefulness than in those without this symptom. The preoperative TNF-alpha levels were significantly correlated to the improvement of psychometrical test scores, and of wakefulness and to the overall improvement of the patients following shunt operation. Importantly, shunt operation led to complete disappearance of intrathecal TNF-alpha. We conclude that NPH is correlated with intrathecal TNF-alpha production being reversed following shunt operation in parallel with the clinical improvement. The positive correlation between preoperative TNF-alpha and sulfatide levels in the CSF suggest that intrathecal TNF-alpha may contribute to the damage of the white matter known to occur in patients with NPH.     

TNF-alpha production by U937 promonocytes is enhanced by factors released from HIV-infected T4 lymphocytes: TNF-alpha is one of the mediators causing lysis of HIV-infected T4 cells.

In the present study, we have shown that the addition of culture supernatants from HIV-infected SupT1 cells (T4) but not from noninfected cells markedly increased the production of TNF-alpha by U937 promonocytic cells after stimulation with phorbol 12-myristate 13-acetate (PMA). Pretreatment of supernatants with the antibodies to granulocyte/macrophage colony-stimulating factor (GM-CSF) or TNF-alpha, but not interferon-gamma, significantly diminished this enhancing effect. These results suggest that HIV may play an indirect role by producing cytokines from infected T4 cells that can lead to an increased production of TNF-alpha by monocytic cells. Further, TNF-alpha produced by U937 cells following stimulation with PMA plus lipopolysaccharide or with phytohemagglutinin induced lysis of HIV-infected T cells. TNF-alpha-induced cytotoxicity was markedly higher toward HIV-infected than toward noninfected T4 cells. Addition of antibody to TNF-alpha during the cytotoxic phase of response resulted in a reduction of about 50% in the percentage of cytotoxicity, indicating TNF-alpha as one of the lytic mediators.     

Normal lymphocyte interferon production in adult HBsAg-positive chronic active liver disease

To challenge the hypothesis that interferon (IF) production in chronic hepatitis-B virus liver disease is defective, lymphocytes from 14 patients with chronic active liver disease (CALD); from nine patients with chronic inactive liver disease (CILD), and from six healthy chronic carriers (HCC) were stimulated by Newcastle Disease virus. The patients with CILD showed a weak IF response by comparison with the controls (P less than 0.0005), whereas IF production by CALD patients and the HCC did not statistically differ from IF production in the healthy hepatitis-B surface antigen negative subjects who served as controls. These results indicate that IF treatment of CALD does not rely on a completely proved background.