Cleaving the oxidative repair protein Ape1 enhances cell death mediated by granzyme A

The cytolytic T lymphocyte protease granzyme A (GzmA) initiates a caspase-independent cell death pathway. Here we report that the rate-limiting enzyme of DNA base excision repair, apurinic endonuclease-1 (Ape1), which is also known as redox factor-1 (Ref-1), binds to GzmA and is contained in the SET complex, a macromolecular complex of 270-420 kDa that is associated with the endoplasmic reticulum and is targeted by GzmA during cell-mediated death. GzmA cleaves Ape1 after Lys31 and destroys its known oxidative repair functions. In so doing, GzmA may block cellular repair and force apoptosis. In support of this, cells with silenced Ape1 expression are more sensitive, whereas cells overexpressing noncleavable Ape1 are more resistant, to GzmA-mediated death.     

The effects of dexamethasone and chlorpromazine on tumour necrosis factor-alpha, interleukin-1 beta, interleukin-1 receptor antagonist and interleukin-10 in human volunteers.

Tumour necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) are pro-inflammatory cytokines that play an important role in severe infections, whereas IL-1 receptor antagonist (IL-1ra) and IL-10 are anti-inflammatory cytokines that counteract their effects. Chlorpromazine and dexamethasone protect mice against lethal endotoxaemia by decreasing circulating concentrations of TNF-alpha and IL-1 beta. We investigated whether administration of chlorpromazine or dexamethasone to human volunteers is able to modulate the lipopolysaccharide (LPS)-stimulated cytokine production capacity in whole blood. Blood samples were taken before and several time-points after medication. Circulating cytokine concentrations were low in all samples. LPS-induced TNF-alpha and IL-1 beta production in whole blood was inhibited by dexamethasone treatment, while chlorpromazine had no effect. When peripheral blood mononuclear cells were stimulated in vitro with LPS, the addition of chlorpromazine (1-100 ng/ml) had no modulatory action on TNF-alpha, IL-1 beta, IL-1ra or IL-10 synthesis. The chlorpromazine concentrations measured in circulation of volunteers were eight to 40 times lower than the concentrations shown to be effective in mice. In conclusion, chlorpromazine inhibits TNF-alpha and IL-1 beta production in mice at concentrations that cannot be reached in humans, thus precluding its usage in clinical anti-cytokine strategies. In contrast, dexamethasone is an effective inhibitor of pro-inflammatory cytokine production.     

Interrelationships of interleukin-8 with interleukin-1beta and neutrophils in vaginal fluid of healthy and bacterial vaginosis positive women

Vaginal innate immunity in response to microbial perturbation is still poorly understood and could be crucial for protection from adverse outcomes. We investigated the relationship between interleukin (IL)-8, IL-1beta and neutrophils in vaginal fluid obtained from 60 healthy women and 51 women who were bacterial vaginosis (BV) positive. Concentrations of IL-8 and IL-1beta were highly correlated with counts of neutrophils in vaginal fluid of the entire population examined (111 subjects). Vaginal IL-1beta concentrations were significantly higher (P < 0.001) in BV positive women. There was no significant difference in IL-8 levels or number of neutrophils between healthy controls and BV positive women. None of the healthy controls with high neutrophil counts (> or =75th percentile, 14 average count per field) had high concentrations of IL-1beta (> or =75th percentile, 220 pg/ml), whereas 84% of BV positive women with high neutrophil counts had high IL-1beta concentrations (P < 0.001). On the contrary, no difference in the percentage of subjects with elevated concentrations of IL-8 (> or =75th percentile, 2842 pg/ml) was found between healthy and BV positive women with high numbers of neutrophils (55.5% of healthy versus 53% of BV positive women). Our findings show that BV causes a large increase in IL-1beta concentrations which is not paralleled by an increase in IL-8 concentrations in vaginal fluid, suggesting that BV-associated factors more specifically dampen IL-8 rather than IL-1beta. The lack of an increase in IL-8 may explain the absence of an increase in neutrophil numbers in most women exposed to abnormal vaginal colonization (BV).     

The interleukin-1 beta +3953 single nucleotide polymorphism: cervical protein concentration and preterm delivery risk

PROBLEM: To determine the associations between preterm delivery <37 weeks (PTD), cervical fluid interleukin-1beta (IL-1beta) concentration, and its +3953 single nucleotide polymorphism (SNP). METHOD OF STUDY: Cervical fluid, peripheral blood, and cord blood samples were obtained from a cohort of women 23-32 weeks gestation with preterm labor symptoms and intact membranes. RESULTS: Increased cervical fluid concentrations of IL-1beta were associated with PTD (P = 0.017) and spontaneous PTD (P = 0.001). Maternal IL-1beta +3953 SNP genotype was associated neither with PTD (P = 0.43) nor with cervical fluid IL-1beta concentrations (P = 0.35). Neonatal IL-1beta +3953 SNP genotype was associated neither with PTD nor cervical IL-1beta concentrations. CONCLUSIONS: Cervical fluid concentrations of IL-1beta were elevated in symptomatic women destined to have a spontaneous PTD. The gene dosage of maternal IL-1beta +3953 allele 2 was associated neither with increased cervical fluid concentrations of IL-1beta nor with risk of PTD.     

Danazol suppresses the production of interleukin-1 beta and tumor necrosis factor by human monocytes

The effects of estradiol (E2), progesterone (P), and danazol on the production of interleukin-1 beta (IL-1 beta) and tumor necrosis factor (TNF) by OK-432 (a streptococcal preparation)-stimulated monocytes were examined. E2 and P at physiologic concentrations enhanced IL-1 beta and TNF production by monocytes from donors with lower control levels (without steroids added) of IL-1 beta and TNF. However, E2 and P at physiologic concentrations did not affect IL-1 beta and TNF production by monocytes from donors with higher control levels of IL-1 beta and TNF. Danazol inhibited IL-1 beta and TNF production by monocytes in a dose-dependent manner from not only donors with lower control levels of IL-1 beta and TNF but also donors with higher control levels of IL-1 beta and TNF. Danazol at a concentration of 10(-6) M significantly suppressed IL-1 beta and TNF production in the presence of E2 and/or P at concentrations giving peak responses of IL-1 beta production. These findings suggest possible new mechanisms of action for danazol in the treatment of endometriosis and infertility associated with immune abnormalities.     

Possible contribution of follicular interleukin-1beta to nitric oxide generation in human pre-ovulatory follicles

The aim of this study was to investigate the relationships between follicular nitric oxide (NO) metabolite concentrations and several related variables, with special reference to follicular interleukin- 1beta (IL-1beta). The follicular fluid from the leading and secondary follicles was collected individually from 20 women undergoing in-vitro fertilization (IVF) treatment, and the concentrations of nitrite (NO2-) and nitrate (NO3-) were determined fluorometrically using 2,3- diaminonaphthalene. Both follicular nitrite (r = 0.42, P < 0.01) and nitrate (r = 0.49, P < 0.001) were found to be significantly correlated with follicular IL-1beta concentrations. There were also significant positive correlations between follicular nitrate and the number of oocytes retrieved (P < 0.01) and serum oestradiol concentration on the day of human chorionic gonadotrophin (HCG) administration (P < 0.05). When follicular cells were incubated in vitro with 10 ng/ml of IL-1beta for 24 h, nitrate generation was significantly (P < 0.01) elevated compared with the control. In conclusion, our study demonstrates that follicular IL-1beta and the number of developing follicles are significant variables that affect follicular NO concentrations, and points to the possible contribution of IL-1beta to NO generation in human preovulatory follicles.      

Effect of immune cytokines on bone

The effect of the bone resorptive cytokines IL-1 alpha, IL-1 beta, and TNF on bone formation was studied in an in vitro system. All three cytokines were profoundly inhibitory, with the rank order of potency IL-1 beta greater than IL-1 alpha greater than TNF. Inhibition was mediated by a depression of differentiated osteoblast functions, including alkaline phosphatase expression and matrix synthesis. Osteoblast proliferation was not affected. Bone formation inhibition was independent of PGE2 production, indicating a direct effect of cytokines on osteoblasts. High concentrations of IL-1 beta (10 U/ml) abrogated IGF-1-stimulated bone formation, providing evidence for the hypothesis that cytokines act as 'uncoupling factors'. Conversely, high concentrations of IGF-1 circumvented inhibition by IL-1 beta (0.1-1.0 U/ml). The interaction of cytokines and bone growth factors with osteoblasts are likely to be of critical importance in the regulation of bone mass at local inflammatory sites.     

Decreased proinflammatory cytokines in cervicovaginal fluid, as measured in midgestation, are associated with preterm delivery

PROBLEM: The main aim of this study was to investigate the relationship between selected proinflammatory cytokines [interleukin IL-1 alpha (IL-1alpha), IL-1 beta (IL-1beta), IL-6 and IL-8] concentrations in cervicovaginal fluid, as measured in midgestation, and the risk of subsequent preterm delivery. METHOD OF STUDY: Cervicovaginal fluids were obtained from a cohort of 114 pregnant women at 22-34 weeks' gestation and analyzed for the concentrations of IL-1alpha, IL-1beta, IL-6 and IL-8 using enzyme-linked immunosorbent assay technique. Lower genital tract microbiology was diagnosed using Gram stain method and by culture. RESULTS: Mean gestational age at the time of sampling was 29.0 weeks. Mean time between sampling and delivery was 9.3 weeks (S.D. 4.7). Median cervicovaginal concentrations of IL-1alpha, IL-1beta, IL-6 and IL-8 did not differ between preterm and term delivery group. Women with lower genital tract pathological flora and IL-1alpha concentration below 25th percentile presented significant risk of subsequent preterm delivery as compared with women with no low cytokines (OR = 10.7; 95% CI, 2.0-58.1). Women with more than one cytokine' low concentration (below 25th percentile) presented an increased risk of preterm delivery--OR = 11.8 (95% CI, 1.8-78.0). CONCLUSIONS: The midgestation cytokines' measurement in cervicovaginal fluid of pregnant women could be useful for prediction of preterm delivery only among women with lower genital tract pathological flora.     

Seminal cytokine concentrations (IL-1beta, IL-2, IL-6, sR IL-2, sR IL- 6), semen parameters and blood hormonal status in male infertility

Several lines of evidence indicate that cyokines are involved in male fertility. They are secreted by different parts of the male genital tract and may exert effects on steroidogenesis, spermatogenesis and sperm functions. We measured the concentrations of interleukins (IL- beta, IL-2, IL-6) and those of interleukin soluble receptors (sR IL-2, SR IL-6) in semen of fertile subjects (n = 21) and of patients with a range of andrological diseases (n = 119). The seminal concentrations of cytokines were analysed according to semen parameters as well as to the blood hormonal profiles of follicle stimulating hormone, luteinizing hormone and testosterone. An increase of IL-1beta was observed in the group of patients with infertility. No difference was found between the different subgroups defined on the basis of progressive motility, percentage of abnormal forms and diagnosis of infection. The seminal cytokine concentrations were independent of the blood hormonal status. Our data suggest that the determination of interleukins (-1beta, -2 and -6) or interleukin soluble receptors (sR IL-2, sR IL-6) in human spermatozoa does not provide convenient information in male routine infertility work-up.      

Extracellular regulation of interleukin (IL)-1beta through lung epithelial cells and defective IL-1 type II receptor expression

Interleukin (IL)-1beta is produced primarily by activated mononuclear phagocytic cells in the lung airway and functions as a potent proinflammatory cytokine. Release of IL-1beta in the airway microenvironment induces the production of proinflammatory factors from parenchymal airway cells, including IL-8. To study the regulation of lung epithelial cell responsiveness to IL-1beta, the human type II-like airway epithelial cell line A549 and primary normal human bronchial epithelial (NHBE) cells were assayed for IL-1-specific response modifiers. Specifically, the IL-1 type I receptor (IL-1RI), IL-1 type II receptor (IL-1RII), IL-1 receptor accessory protein (IL-1RAcP), and IL-1 receptor antagonist (IL-1Ra) were analyzed. Constitutive expression of IL-1RI, IL-1RAcP, and IL-1Ra was detected in both immortalized and primary human airway epithelial cells. Interestingly, a complete absence of IL-1RII expression was demonstrated under all study conditions in both A549 and NHBE cells. Both cell types were responsive to IL-1beta at concentrations as low as 50 to 500 pg/ml when measured by IL-8 release into cell supernatants. IL-1beta-induced chemokine production and release were inhibited by a 10- to 1,000-fold molar excess of recombinant IL-1RII or IL-1Ra, whereas IL-1RI was a less effective inhibitor. On the basis of our results, we propose that human lung epithelial cells lack the ability to downregulate IL-1beta activity extracellularly because of an inability to express IL-1RII. Release of extracellular IL-1 inhibitors, including soluble IL-1Ra and soluble IL-1RII, by other inflammatory cells present in the airway may be critical for regulation of IL-1beta activity in the airway microenvironment.     

Platelet-activating factor modulates interleukin-6 production by mouse fibroblasts

We compared the effects of platelet-activating factor (PAF), interleukin-1 beta (IL-1 beta) and polyriboinositic-polyribocytidylic acid (poly-I:C) on IL-6 production by confluent L929 mouse fibroblasts. At concentrations above 1 microM, PAF dose-dependently enhanced IL-6 production; at 5 microM PAF this increase (72.7 +/- 19.9 U/ml) was higher than that evoked by 100 U/ml IL-1 beta (5.7 +/- 0.4 U/ml) or 50 micrograms/ml poly-I:C (39.3 +/- 6.7 U/ml). The IL-6 production induced by 5 microM PAF was not inhibited by addition of the specific PAF antagonist BN 52021 (10 microM) to the incubation medium. These results demonstrate that, as this is the case for IL-1, PAF also modulates IL-6 production.     

Cytokines in the follicular fluid of stimulated and non-stimulated human ovaries; is ovulation a suppressed inflammatory reaction?

We determined the concentrations of tumour necrosis factor (TNF)-alpha, interleukins (IL)-1 beta, -6, -8 and -1-receptor antagonist (IL-1-ra) and of oestradiol and progesterone in the follicular fluid of 111 women undergoing in-vitro fertilization (IVF) and of six women with ovarian cysts in order to elucidate mid-cycle mechanisms causing dissociation of the follicle wall and local rupture of the ovarian tissue complex. Four stimulation protocols were administered: gonadotrophin releasing hormone agonist/human menopausal gonadotrophin (GnRHa/HMG), clomiphene citrate/HMG (CC/HMG), HMG and follicle-stimulating hormone (FSH). Concentrations of TNF alpha and IL-1 beta were below 15 and 3 pg/ml respectively. IL-6 (median 4.1, 3.5-4.4 pg/ml, 95% CI) was higher after stimulation with FSH (5.6 pg/ml) than with HMG (3.2 pg/ml, P < 0.05) or GnRHa/HMG (3.7 pg/ml, P < 0.05), and after stimulation with CC/HMG (5.5 pg/ml) than with HMG (P < 0.01) or GnRHa/HMG (P < 0.001). IL-8 ranged from 32 to 1241 pg/ml (147, 117-178 pg/ml) and IL-1-ra from < 31 to > 10,000 pg/ml (156, 109-192 pg/ml). Cytokine levels did not correlate to oestradiol or progesterone concentrations. The ovarian cysts contained similar IL-8 (14-540 pg/ml) and IL-1 beta (< 30 pg/ml), but higher IL-6 (13.6-> 500 pg/ml) and lower IL-1-ra concentrations. We assume that IL-6, IL-8 and IL-1-ra are involved in peri-ovulatory cellular interactions. Thus, ovulation appears to be a cytokine-regulated process of an 'inflammation' (IL-6 and IL-8) followed by 'anti-inflammatory' reactions (IL-1-ra).     

Serum cytokine responses during acute human granulocytic ehrlichiosis

Human granulocytic ehrlichiosis (HGE) is caused by obligate intracellular bacteria in the Ehrlichia phagocytophila group. The disease ranges from subclinical to fatal. We speculated that cell-mediated immunity would be important for recovery from and potentially in the clinical manifestations of HGE; thus, serum tumor necrosis factor alpha (TNF-alpha), interleukin 1beta (IL-1beta), gamma interferon (IFN-gamma), IL-10, and IL-4 concentrations were studied. IFN-gamma (1,035 +/- 235 pg/ml [mean +/- standard error of the mean]) and IL-10 (118 +/- 46 pg/ml) concentrations were elevated in acute-phase sera versus convalescent sera and normal subjects (P 相似文献   

Migration of langerhans cells and dermal dendritic cells in skin organ cultures: augmentation by TNF-alpha and IL-1beta.

Migration from sites of antigen encounter to lymphoid organs is essential to the strong immunogenic function of dendritic cells (DC). In the skin, migration proceeds through dermal lymphatic vessels and is regulated in an incompletely understood way by inflammatory mediators. We studied the effects of tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta) in mouse skin organ cultures by direct enumeration of migrating DC and by immunohistochemistry. (1) Neutralizing antibodies to TNF-alpha and IL-1beta inhibited migration of DC, also in human skin explants (TNF-alpha). (2) TNF-alpha at low concentrations (50 U/mL) and IL-1beta (50-3000 U/mL) augmented migration to about 150% of spontaneous migration. (3) High concentrations of TNF-alpha (5000 U/mL) inhibited migration by approximately 50%. (4) DC migration from skin explants of TNF-alpha/lymphotoxin-alpha double-deficient mice and TNF-receptor type 1 and 2 double knockout mice was not impaired. (5) TNF-alpha effects were neutralized by anti-IL-1beta, and vice versa. We conclude that in normal animals both TNF-alpha and IL-1beta are required for DC migration to occur. In the complete absence of one cytokine (TNF-alpha), however, backup mechanisms step in.     

Proinflammatory cytokines induce lymphocyte apoptosis in acute African swine fever infection

Twenty-one pigs inoculated with a highly virulent isolate (E70) of African swine fever (ASF) virus were killed 1-7 days later; a further three animals served as uninfected controls. An early increase in TNF-alpha, IL-1alpha, IL-1beta and IL-6 expression was detected in lymphoid organs from infected animals, together with an increase in the serum concentrations of TNF-alpha and IL-1beta. These changes were accompanied by increased apoptosis of lymphocytes, and the presence of infected and uninfected macrophages showing changes indicative of secretory and phagocytic activation. The present study demonstrated an increase in the number of macrophages expressing TNF-alpha, IL-1 and IL-6 in proximity to lymphocytes undergoing apoptosis, supporting previous suggestions that in acute ASF proinflammatory cytokines induce lymphocyte apoptosis.     

Advanced glycation end products upregulate C-reactive protein synthesis by human hepatocytes through stimulation of monocyte IL-6 and IL-1 beta production

Patients with chronic renal failure are characterized by increased plasma levels of C-reactive protein (CRP) and advanced glycation end products (AGE). AGE have been identified as a class of proinflammator mediators. To investigate whether AGE can stimulate hepatocytes to produce CRP, primary human fetal hepatocytes (HFH) were incubated with AGE-modified human serum albumin (AGE-HSA) or conditioned medium from AGE-HSA-stimulated monocytes (AGE-MCM). CRP concentrations in the supernatants were determined by an ELISA and CRP mRNA levels were determined by a quantitative RT-PCR. Exposure of HFH with AGE-HSA for 12-72 h did not change CRP concentrations in the supernatants. CRP protein and mRNA expression were significantly upregulated in a time- and dose-dependent manner when HFH were incubated with AGE-MCM. This stimulating effect was partially inhibited when AGE-MCM were preincubated with antibodies against interleukin-6 (anti-IL-6), interleukin-1 beta (anti-IL-1 beta), or soluble IL-1 receptor and was completely inhibited when AGE-MCM were preincubated with anti-IL-6 and anti-IL-1 beta simultaneously. The inhibiting effect did not occur when AGE-MCM was preincubated with antibody of tumour necrosis factor-alpha (anti-TNF-alpha) and soluble TNF receptor. Exposure of HFH with exogenous IL-6 and IL-1 beta, at the same concentrations as contained in AGE-MCM, also increased CRP production, but exogenous TNF-alpha had no effect. These results suggest that AGE cannot directly stimulate hepatocytes to produce CRP, but rather indirectly enhance CRP expression via stimulation of IL-6 and IL-1 beta production by human monocytes.     

The effect of testosterone on cytokine production in the specific and non-specific immune response

PROBLEM: Cytokine production of monocytes and lymphocytes differs between males and females. This difference is characterized by a decreased percentage of interleukin (IL)-2-producing lymphocytes and an increased percentage of IL-12, IL-1beta and tumour necrosis factor (TNF)-alpha-producing monocytes in males compared with females. In the present study, we investigated whether testosterone may explain these differences. METHOD OF STUDY: Stimulated whole blood of healthy woman was incubated with different concentrations of testosterone. Intracellular lymphocyte production of IL-2 and interferon (IFN)-gamma, as well as intracellular monocyte production of IL-12, IL-1beta and TNF-alpha were measured using flow cytometry. RESULTS: A significant increased percentage of IL-12- and IL-1beta-producing monocytes was found after incubation with physiological concentrations of testosterone. No effect of testosterone was found on IL-2- and IFN-gamma-producing lymphocytes and TNF-alpha-producing monocytes. CONCLUSIONS: The increased percentage of IL-12- and IL-1beta-producing monocytes in males compared with females in vivo may be induced by testosterone, as the in vitro percentage of IL-12- and IL-1beta-producing monocytes is increased after incubation with physiological concentrations of testosterone.