The effect of tumor necrosis factor on human sperm motility in vitro

Tumor necrosis factor (TNF alpha) is present in elevated levels in peritoneal fluid from infertile women with endometriosis. The effect of TNF alpha on human sperm motility in vitro was evaluated utilizing peritoneal fluid from infertile women with minimal endometriosis containing 0, 100, 400, or 800 U of TNF alpha/ml as well as similar concentrations of recombinant human TNF alpha. No reduction in progressive and total motility was found at recombinant TNF alpha concentrations of 100 U ml. However, 500 and 1000 U of recombinant TNF alpha/ml caused a significant reduction in progressive and total sperm motility after 4 and 21 hours of incubation when compared with controls. Similarly, peritoneal fluid containing 100 U of TNF alpha/ml did not significantly reduce progressive and total sperm motility after either 4 or 21 hours of incubation; but peritoneal fluid containing 400 U of TNF alpha/ml reduced progressive sperm motility after 4 and 21 hours and total sperm motility after 21 hours of incubation. Peritoneal fluid with a TNF alpha concentration of 800 U/ml caused a significant reduction in both progressive and total sperm motility after 4 and 21 hours when compared with controls of TNF alpha-negative peritoneal fluid. The addition of polyclonal rabbit anti-TNF alpha antibody or 30-min heat inactivation at 56 C of TNF alpha-positive peritoneal fluid reversed the inhibitory effect on sperm motility. The ability of TNF alpha to cause a significant reduction of sperm motility in vitro suggests that this may be a mechanism for the infertility observed in women with minimal endometriosis.     

子宫内膜异位症患者腹腔巨噬细胞释放细胞因子能力的变化及与环核苷酸水平的关系

本研究观察了轻度子宫内膜异位症（异位症）患者腹腔巨噬细胞释放肿瘤坏死因子（ＴＮＦα）和白细胞介素６（ＩＬ ６）的变化及与环核苷酸水平的关系。结果显示：与对照组相比，异位症患者腹腔巨噬细胞数量增多，释放ＴＮＦα和ＩＬ ６的能力明显增强。同时异位症患者腹腔巨噬细胞ｃＧＭＰ水平较对照组明显升高（Ｐ＜０．０１），ｃＡＭＰ水平明显降低（Ｐ＜０．０１），ｃＡＭＰ／ｃＧＭＰ比值也显著降低（Ｐ＜０．０１）。表明异位症患者腹腔巨噬细胞活性改变与细胞内第二信使系统———环核苷酸水平变化有关。     

Polymyxin B antagonizing biological activity of lipopolysaccharide

Objective ： To investigate the mechanism of polymyxin B （ PMB ） antagonizing the biological activity of Hipopolysaccharide （LPS）. Methods： The affinity of PMB for LPS and lipid A was assayed by biosensor, and the neutralization of PMB for LPS （2 ng/ml ） was detected by kinetic turbidimetric limnins test. The releases of TNF-α and IL-6 in murine peritoneal macrophages （PMφ） after exposure to LPS （ 100 ng/ml） were detected, and the expression levels of TLR4, TNF-α and IL-6 mRNA in PMφ induced by LPS （100 ng/ml） were measured by RT-PCR. Results： PMB had high-affinity to LPS and lipid A with dissociation equilibrium constants of 18.9 nmol/L and 11.1 nmol/L, respectively, and neutralized LPS in a dosedependent manner. Furthermore, PMB could markedly inhibit the expressions of TLR4, TNF-α and IL-6 mRNA and the release of cycokines in LPS-stimniated murine PMφ. Conclusions： PMB neutralizes LPS and inhibites the expression and release of cycokines in macrophages, in which the affinity of PMB for lipid A plays an important role.     

依那西普对磨屑诱导巨噬细胞分泌肿瘤坏死因子的影响

目的 探讨依那西普(etanercept)对人工关节无菌性松动的影响.方法 分离、培养小鼠腹腔巨噬细胞,分为5组.A组为单纯巨噬细胞组,B组为细胞 钛颗粒组,C组为细胞 钛颗粒 10ng/ml依那西普组,D组为细胞 钛颗粒 100 ng/ml依那西普组,E组为细胞 钛颗粒 1000 ng/ml依那西普组.培养18小时后,用酶联免疫吸附试验检测细胞培养上清液中肿瘤坏死因子含量.结果 A、C、D、E组肿瘤坏死因子含量明显低于B组(P＜0.001),E组肿瘤坏死因子含量明显低于C组和B组(P＜0.001).结论 磨屑可刺激巨噬细胞分泌肿瘤坏死因子,依那西普能够呈剂量依赖地有效抑制磨屑诱导的巨噬细胞分泌肿瘤坏死因子,有望成为预防人工关节无菌性松动的药物.     

Inverse MCP-1/IL-8 ration in effluents of CAPD patients with peritonitis and in isolated cultured human peritoneal macrophages

An important event in intraperitoneal inflammation is the influx of leukocytes into the peritoneal cavity. Chemokines such as interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) play a major role in the recruitment of immune cells to the site of inflammation. We determined the concentrations of two members of the chemokine family, IL-8 and MCP-1, in the dialysate effluents of 18 continuous ambulatory peritoneal dialysis (CAPD) patients with peritonitis and of 18 non-infected CAPD patients by specific enzyme-linked immunosorbent assays (ELISA). Isolated peritoneal macrophages (PMs) from CAPD peritonitis patients were cultured and IL-8 and MCP-1 production was determined on protein (ELISA) and mRNA level (Northern blot) at designated timepoints over a 72-h culture period. PMs from non-infected patients served as controls. Much higher concentrations of IL-8 and MCP-1 were found in dialysate effluents of peritonitis patients than in effluents of non-infected patients: IL-8 2.39&plusnn;1.15 vs 0.05±0.01 ng/ml and MCP-1 release by cultured PMs from peritonitis patients and non-infected patients revealed significant differences: IL-8 40.3±2.2 ng/ml after 3 h and 194.2 ±34.9 ng/ml after 12 h compared to 21.02±6.15 ng/ml after 3 h and 89.64±30.28 ng/ml after 12 h, respectively; MCP-1 3.3±0.9 ng/ml after 3 h and 25.7±7.4 ng/ml after 12 h compared to 1.1±0.2 ng/ml and 1.8±0.2 ng/ml, respectively. Interestingly, the ratio of IL-8 to MCP-1 concentrations in the dialysate effluents (1:9.4) is reversed in the supernatants of cultured PMs. In the effluents and in the culture supernatants of PMs from CAPD peritonitis patients high amounts of IL-8 and MCP-1 are detectable, suggesting that PMs are an important source for these chemokines during peritonitis. Because of the inverse ratio of IL-8 and MCP-1 in the effluents and culture supernatants it can be assumed that PMs are responsible for the MCP-1 concentration to a lesser extent than for the IL-8 concentration in the effluents.     

Interleukin-1 beta stimulates human mesangial cells to synthesize and release interleukins-6 and -8.

Interleukin-1 beta (IL-1 beta) and tumor necrosis factor (TNF) have been reported to stimulate human mesangial cells (HMC) to proliferate and synthesize eicosanoids. We have examined whether they also induce HMC to release cytokines. In this study we show that both IL-1 and TNF stimulate HMC to release IL-6 and IL-8. Cycling and quiescent HMC were stimulated with various concentrations of either recombinant IL-1 beta or TNF for 1 to 24 hours. IL-1 beta at doses as low as 6 pg/ml stimulated mesangial cells to synthesize mRNA for both IL-6 and IL-8 as assessed by Northern analysis; mRNA for tubulin remained constant, which demonstrated a specific increase in mRNA. Secretion of IL-6 and IL-8 into the culture medium increased (4.5 to 18 ng/ml and 4 to 40 ng/ml, respectively) measured by ELISAs. TNF had similar effects but only in high concentrations (greater than 100 ng/ml). IL-1 beta did not stimulate cells to proliferate, as measured by 3H thymidine incorporation. TNF caused proliferation but only in concentrations over 100 ng/ml. We conclude that IL-1 beta is a potent stimulator of human mesangial cell production of IL-6 and IL-8, both of which may influence injury in nephritis. TNF also stimulates mesangial cells but only in pharmacological doses.     

Inhibition of cytokine synthesis by peritoneal dialysate persists throughout the CAPD cycle.

The current study focused on the effect of continuous ambulatory peritoneal dialysis (CAPD) dialysate obtained following different intraperitoneal dwell periods on the release of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF alpha) from mononuclear leukocytes (PBMC). Aliquots of 5 x 10(6)/ml healthy peripheral PBMC were exposed to fresh or spent CAPD dialysate (10-240 min of intra-peritoneal dwell) and stimulated with Escherichia coli endotoxin (10 micrograms/ml, 2h). IL-6 and TNF alpha in cell supernatants were determined by specific enzyme immunoassays. Control PBMC in physiological buffer released 361 +/- 70 pg/ml IL-6 and 717 +/- 147 pg/ml TNF alpha (mean +/- SEM, n = 8), whereas exposure to fresh dialysis fluids severely suppressed cytokine release from PBMC (less than 30 pg/ml IL-6 and less than 15 pg/ml TNF alpha). A significant inhibition of IL-6 and TNF alpha release was also observed in PBMC exposed to spent dialysate. The inhibitory capacity of the spent fluids was pronounced with increasing intra-peritoneal dwell time (10 min: 183 +/- 45 pg/ml IL-6 and 538 +/- 109 pg/ml TNF alpha; 240 min: 26 +/- 5 pg/ml IL-6 and 105 +/- 30 pg/ml TNF alpha; mean +/- SEM, n = 16). These data indicate that the impairment of cell responsiveness following exposure of PBMC to peritoneal dialysate is not restricted to the unused fluids, but is also observed following intra-peritoneal equilibration. Moreover, our findings suggest the presence of cytokine inhibitory factors in the peritoneal dialysate of CAPD patients which appear to accumulate in the peritoneal effluent during the CAPD cycle.     

Relative hyperoxia augments lipopolysaccharide-stimulated cytokine secretion by murine macrophages

BACKGROUND: Increased systemic levels of inflammatory mediators are seen after open abdominal operations. Macrophages that are exposed to lipopolysaccharide secrete cytokines. Peritoneal macrophages normally reside in a pO(2) of 40 mm Hg. We hypothesize that exposure of lipopolysaccharide-stimulated macrophages to "non-physiologic" pO(2) augments cytokine secretion. METHOD: Murine macrophages were preconditioned to a pO(2) of 40 mm Hg for 24 hours. The medium then was discarded and exchanged for a medium containing a pO(2) of 40, 150, or 440 mm Hg. Macrophages were incubated in the desired pO(2) for 6 and 24 hours while stimulated with lipopolysaccharide (0 to 100 ng/mL). The effect of pO(2) was compared. Supernatant tumor necrosis factor (TNF) and interleukin-6 were measured with enzyme-linked immunosorbent assay. Statistics were performed with analysis of variance. RESULTS: We found dose-dependent lipopolysaccharide-stimulated TNF and interleukin-6 production with macrophages incubated at physiologic pO(2). Higher pO(2) did not stimulate TNF and interleukin-6 in the absence of lipopolysaccharide. However, a pO(2) of 150 and 440 mm Hg significantly (P <.05) increased lipopolysaccharide-stimulated TNF and interleukin-6 production versus 45 mm Hg. CONCLUSION: Our data suggest synergy between increased pO(2) and lipopolysaccharide for macrophage TNF and interleukin-6 production. Similar pO(2) elevations may occur with an open peritoneum or high supplemental O(2). Cytokines from peritoneal macrophages may contribute to the increased systemic inflammation after open operations.     

Danazol induces prolonged survival of fully allogeneic cardiac grafts and maintains the generation of regulatory CD4(+) cells in mice

Danazol, a derivative of testosterone, is useful for treatment of endometriosis as well as pretreatment for in vitro fertilization and embryo transfer, although its mechanisms of action are unclear. The aim of this study was to investigate the effect of danazol on alloimmune responses in murine heart transplantation. CBA male mice (H2(k) ) underwent transplantation of C57BL/6 male (H2(b) ) hearts and received a single dose of danazol (0.4, 1.2 or 4mg/kg/day) by intraperitoneal injection on the day of transplantation and for 6days thereafter. An adoptive transfer study was performed to determine whether regulatory cells were generated. The median survival time (MST) of allografts in danazol-treated (1.2 and 4mg/kg/day) mice was 28 and 63days, respectively, compared with 7days in untreated mice. Moreover, secondary CBA recipients given whole splenocytes or CD4(+) cells from primary danazol-treated (4mg/kg/day) CBA recipients 30days after transplantation had prolonged allograft survival (MSTs, 29 and 60days, respectively). Cell proliferation, interleukin (IL)-2 and interferon-γ were suppressed in danazol-treated mice, whereas IL-4 and IL-10 were up-regulated. Moreover, danazol directly suppressed allo-proliferation in a mixed leukocyte culture. Flow cytometry showed an increased CD4(+) CD25(+) Foxp3(+) cell population in splenocytes from danazol-treated mice. Danazol prolongs cardiac allograft survival and generates regulatory CD4(+) cells.     

Lipopolysaccharide-binding protein is present in effluents of patients with Gram-negative and Gram-positive CAPD peritonitis

Background: Bacterial peritonitis is a frequent complication during treatment of end-stage renal failure by continuous ambulatory peritoneal dialysis. Local host defence mechanisms including the secretion of proinflammatory cytokines by peritoneal macrophage are of particular importance in the pathogenesis of infectious complications. LPS-binding protein (LBP) and soluble CD14 (sCD14) are serum factors known to regulate the endotoxin-induced cellular immune response. However, it is still unknown whether LBP and sCD14 are also present in the peritoneal effluent of CAPD patients. Methods: Using specific immunoassays, we examined the concentration of LBP, sCD14 and the proinflammatory cytokines TNF=&agr;, IL-1{beta} and IL-6 in the dialysis effluents of 31 patients with CAPD-associated peritonitis. Twenty patients without peritonitis served as controls. Intraperitoneal LPS concentrations were determined using the limulus amebocyte lysate assay. Results: Bacterial lipopolysaccharide could be detected in 42% of the infected dialysis effluents. In comparison to controls (0.2±0.05 &mgr;g/ml), LBP was significantly elevated in both Gram-negative/LPS-positive (1.03±0.3 &mgr;g/ml) and Gram-positive infections (0.5±0.14 &mgr;g/ml) (P<0.05). No significant differences were detected concerning the intraperitoneal sCD14 levels in the three patient groups. Levels of TNF-&agr;, IL-1{beta} and IL-6 were significantly increased in the effluents of patients with bacterial peritonitis compared to non-infected controls. Moreover the respective cytokine concentrations were significantly higher in the Gram-negative/LPS-positive compared to the gram-positive bacterial infections (P<0.01). Conclusion: Our data demonstrate that LBP is significantly elevated in the dialysis effluents of patients with CAPD-associated peritonitis caused by both Gram-negative and Gram-positive bacteria and might be used as a marker of intraperitoneal infection. Moreover, our findings support the concept that LBP enhances the effects of LPS on cytokine production by peritoneal macrophages. The function of LBP in Gram-positive infection remains to be further elucidated. Key words: CAPD-associated peritonitis; cytokines; lipopolysaccharide-binding protein; macrophages; peritoneal dialysis; soluble CD14      

Blood leucocyte cytokine production after LPS stimulation at different concentrations of glucose and/or insulin

Background: Previous studies have indicated that alterations in blood glucose and/or insulin levels modify the inflammatory response. The purpose of this study was to elucidate whether increased levels of glucose and/or insulin influence the activation pattern of blood leucocytes and their production of cytokines in vitro .
Methods: Venous blood was obtained from eight healthy male volunteers after an overnight fast. Glucose and/or insulin were added to aliquots of whole blood to increase the blood glucose concentration by 5 or 20 mmol/l and/or the insulin concentration by 6 or 30 nmol/l, respectively, before stimulation with E. coli lipopolysaccharide (LPS) at concentrations of 10, 100 or 1000 ng/ml. The samples were subsequently incubated at 37 °C for 6 h before cytokine measurements. After centrifugation the levels of interleukins (IL)-1β, IL-6, IL-8, IL-10 and tumour necrosis factor (TNF)-α were measured in plasma using enzyme-linked immuno-sorbent assays. The results were compared with cytokine levels in parallel control samples to which only identical amounts of LPS were added.
Results: The LPS-stimulated production of IL-1β was significantly reduced by on average 26% in samples to which glucose 20 mmol/l was added; addition of insulin and/or glucose 5 mmol/l had no apparent effect on the IL-1β production at any LPS concentration. The levels of IL-6, IL-8, IL-10 and TNF-α were not manifestly altered by addition of glucose and/or insulin at any LPS concentration.
Conclusion: A substantial increase in blood glucose concentration changed the IL-1β production, but not the production of other cytokines, in response to LPS stimulation.     

信号转导及转录激活子1和3抑制剂对高迁移率族蛋白B1诱导鼠巨噬细胞合成肿瘤坏死因子α的影响

目的探讨信号转导及转录激活子1(STAT1)和3抑制剂对高迁移率族蛋白B1(HMGB1)诱导巨噬细胞合成肿瘤坏死因子α(TNFα)的影响。方法取正常Wistar大鼠腹腔巨噬细胞置24孔培养板中(1×106细胞/孔),培养3d后以HMGB1刺激,采用氟达拉滨(Fludarabine,STAT1特异性抑制剂)及雷帕霉素(Rapamycin,STAT3特异性抑制剂)进行干预。观察HMGB1刺激与肿瘤坏死因子αmRNA表达和蛋白释放的时效、量效关系,Fludarabine和Rapamycin处理对TNFαmRNA表达和蛋白释放的影响。结果(1)HMGB1可导致大鼠腹腔巨噬细胞TNFα基因表达明显升高,于攻击后24h达峰值,至36h减弱。HMGB1的用量为10μg/ml时,TNFα基因表达明显增强;(2)HMGB1可诱导大鼠腹腔巨噬细胞TNFα蛋白早期释放,4h即可达到高峰,8h后减弱。随着HMGB1刺激剂量从5μg/ml增大到25μg/ml,TNFα蛋白释放持续增强;(3)Fludarabine和Rapamycin可抑制大鼠腹腔巨噬细胞TNFα基因表达,但不能影响TNFα蛋白的释放。结论STAT1和STAT3抑制剂可显著下调巨噬细胞由HMGB1诱导的TNFα基因表达,但不能影响其早期(<24h)蛋白释放。     

Circulating concentrations of soluble interleukin 6 receptors gp80 and gp130 in chronic renal failure and effects of renal replacement therapy

BACKGROUND: Circulating receptors modulate the biological effects of cytokines. Renal insufficiency is known to influence the concentrations of the soluble tumor necrosis factor (TNF) receptors p55 and p75. No data are available on the concentrations of the circulating interleukin 6 (IL-6) receptors gp80 and gp130 during chronic renal insufficiency. METHODS: We compared the serum concentrations of the IL-6 receptors gp80 and gp130 to those of the TNF receptors p55 and p75 in end-stage chronic renal failure, continuous ambulatory peritoneal dialysis, and hemodialysis (HD). RESULTS: In healthy controls the concentrations of gp80, gp130, p55, and p75 in serum were 82.1 +/- 24.3, 87.9 +/- 20.2, 1.1 +/- 0.2, and 1.7 +/- 0.3 ng/ml, respectively. These concentrations were increased to, respectively, 112.2 +/- 18.0, 186.0 +/- 37.7, 10.5 +/- 4.3, and 15.0 +/- 7.5 ng/ml in chronic renal failure, to 138.8 +/- 18.0, 181. 3 +/- 46.1, 25.5 +/- 5.2, and 19.1 +/- 3.4 ng/ml in continuous ambulatory peritoneal dialysis, and to 107.9 +/- 29.4, 146.6 +/- 30. 5, 22.9 +/- 6.3, and 16.8 +/- 6.0 ng/ ml in HD (before dialysis session). The concentrations after HD were higher for p75 only. CONCLUSIONS: The data show that the concentrations of the IL-6 receptors (gp80 and gp130) are elevated in chronic renal insufficiency. The increase is relatively low as compared with the elevation of the TNF receptors in this situation. HD does not result in a consistent change in serum concentrations of the various receptors. Copyright Copyright 1999 S. Karger AG, Basel     

重组人生长激素对烫伤小鼠巨噬细胞的影响

目的探讨重组人生长激素(rhGH)、胰岛素样生长因子-1(IGF-1)对烧伤小鼠巨噬细胞(Mφ)功能的影响.方法采用逆转录聚合酶链反应(RT-PCR)和酶联免疫反应方法(ELISA),观察在体和离体应用rhGH、IGF-1对Mφ表达CD14和分泌细胞因子的影响.结果烧伤后应用rhGH及IGF-1均能增加小鼠腹腔MφCD14mRNA的转录和细胞因子的分泌,但两因素之间没有叠加作用.rhGH(40μg/ml)和IGF-1各浓度均可促使培养的小鼠Mφ分泌TNF、IL-6增加.结论rhGH可能由IGF-1介导,通过增加MφCD14的表达激活Mφ,使其更多的分泌细胞因子,有利于增强免疫功能.烧伤后应用0.2mg@kg-1@d-1剂量的rhGH,无过度激活Mφ的作用.     

Macrophage TNF secretion in endotoxin tolerance: role of SAPK, p38, and MAPK.

PURPOSE: Endotoxin (LPS) activation of macrophages results in phosphorylation of mitogen-activated protein kinases (MAPK), stress-activated protein kinases (SAPK), and p38 kinase. LPS pretreatment inhibits subsequent LPS-stimulated MAPK activation and TNF release and both were reversed if macrophages were treated with phorbol myristate acetate (PMA) before LPS stimulation. In this study we sought to determine if SAPK and p38 tyrosine kinases are required for TNF production and if LPS pretreatment alters their activation. METHODS: TNF production by murine peritoneal exudate macrophages was determined 6 h after stimulation with 100 ng/mL of LPS +/- 24 h pretreatment with 10 ng/mL of LPS. The active, diphosphorylated forms of MAPK (p42, p44), SAPK (p46, p54), and p38 were assayed 30 min after LPS stimulation by Western immunoblot using specific antibodies. In some experiments a p38 kinase inhibitor (SB202190) or the protein kinase C activator (PMA) was added 1 h before LPS stimulation. RESULTS: LPS activated MAPK, SAPK, and p38. LPS pretreatment significantly inhibited MAPK, SAPK, and p38 activation by LPS stimulation. TNF protein secretion and MAPK activation in tolerant macrophages were restored by PMA treatment, but this did not restore SAPK activation. The p38 inhibitor SB202190 blocked LPS-stimulated TNF production. CONCLUSION: LPS pretreatment-induced tolerance decreased LPS-stimulated MAP, SAP, and p38 kinase activation. LPS tolerance in murine macrophages appears to be associated with specific, PMA-reversible defects in MAPK and p38 kinase activation.     

利多卡因对LPS诱导大鼠腹腔巨噬细胞NF-κB活性的影响

目的 探讨利多卡因对LPS诱导大鼠腹腔巨噬细胞NF-κB活性的影响.方法 取wistar大鼠腹腔巨噬细胞,以2 × 106/ml的密度接种于12孔培养板,每孔1 ml.纯化处理后随机分为5组,每组10孔.正常对照组(C组)加入RPMI-1640培养液1 ml,L组加入含100 ng/ml LPS的RPMI1640培养液1 ml,LL1组、LL2组和LL3组分别加入含有2、20、200μg/ml利多卡因+100 ng/ml LPS的RPMI-1640培养液1 ml.孵育24 h后,收集上清液,测定高迁移率族蛋白B1(HMGB1)浓度;取细胞沉淀,测定HMGBl mRNA表达水平和NF-κB活性.结果 与C组比较,其他各组HMGB1浓度、HMGB1mRNA表达和NF-κB活性均升高(P＜0.05);与L组及LL1组比较,LL2组和LL3组上述指标降低(P＜0.05).LL3组HMGB1 mRNA表达水平低于LL2组(P＜0.05).结论 利多卡因可抑制LPS诱导大鼠腹腔巨噬细胞NF-κB活化,从而抑制HMGB1的合成与释放.     

Decreased IL-6 secretion by fibroblasts following repeated doses of TNF alpha or IL-1 alpha: post-transcriptional gene regulation

Tumor necrosis factor-alpha (TNF alpha) and interleukin-1 alpha (IL-1 alpha) are pluripotent cytokines mediating the host response to sepsis, injury, and cancer. Animals can be protected from the lethal effects of TNF alpha by repeated administration of sublethal doses, but the mechanism of this effect is not known. Human foreskin fibroblasts (FS4 cells), which rapidly elaborate interleukin-6 (IL-6) when stimulated with TNF alpha or IL-1 alpha, were grown in culture as confluent monolayers and their secretion of IL-6 was quantitated using the murine B9-hybridoma bioassay against an external reference of human recombinant IL-6 (Genetics Institute). When FS4 cells were incubated with human recombinant TNF alpha (50 ng/ml; Cetus) or recombinant IL-1 alpha (30 pg/ml; Genzyme) a rapid increase in IL-6 production was measured over control, rising to IL-6 levels of 71.7 +/- 5.9 units/ml with TNF alpha and 54.0 +/- 1.2 units/ml with IL-1 alpha after 7.5 hr incubation. FS4 cells which were exposed to cytokine, rinsed, and then reexposed to cytokine 24 hr later produced significantly less IL-6 [38.1 +/- 2.8 units/ml with second exposure to TNF alpha (P less than 0.05), and 18.3 +/- 1.9 units/ml with second exposure to IL-1 alpha (P less than 0.01)]. Successive daily exposure to TNF alpha or IL-1 alpha caused a further stepwise diminution of IL-6 secretion.(ABSTRACT TRUNCATED AT 250 WORDS)     

Kinetics of interleukin-1 and tumor necrosis factor secretion by rabbit macrophages recovered from the peritoneal cavity after surgery

Macrophages play a crucial role in wound healing after surgical injury, both as scavenger cells responsible for wound debridement and as cells that secrete soluble factors such as interleukin-1 (IL-1) and tumor necrosis factor (TNF). IL-1 and TNF alter many of the biological activities of cells that appear in postsurgical wounds. In this study, we determined the kinetics of IL-1 and TNF production by rabbit macrophages harvested from postsurgical peritoneal exudate (postsurgical macrophages) at several time points after peritoneal surgery. To further characterize the level of functional activities of postsurgical macrophages, the IL-1 and TNF levels were determined with or without stimulating the cells with lipopolysaccharide (LPS) and phorbol myristate acetate (PMA). After surgery, the number of macrophages harvested by peritoneal lavage increased, reached peak levels on postsurgical day 3, and then decreased. IL-1 levels secreted by macrophages cultured without stimuli were elevated on postsurgical day 14 compared to the values on day 3 and 7. TNF concentrations peaked on days 1 and 14. In the conditioned culture media from LPS-PMA-stimulated macrophages, the levels of both IL-1 and TNF peaked on postsurgical days 3 and 14. These data suggest that the susceptibility of postsurgical macrophages to stimuli changes during the wound healing process with maximum sensitivity to the stimuli present during the early phase of peritoneal repair (day 3).