Effect of azidothymidine (AZT) on HIV P24 antigen, beta 2-microglobulin, neopterin, soluble CD8, soluble interleukin-2 receptor and tumor necrosis factor alpha levels in patients with AIDS-related complex or AIDS

Circulating HIV P24 antigen, beta 2-microglobulin, neopterin, soluble CD8, soluble interleukin-2 receptor and TNF alpha levels were measured in 20 patients (9 with ARC and 11 with AIDS) treated with azidothymidine (AZT) and in 12 patients (3 with ARC and 9 with AIDS) who were in a placebo group. Mean levels of HIV P24 antigen, beta 2-microglobulin, neopterin and SCD8 decreased significantly (P less than 0.05) after 12 to 16 weeks of AZT administration. SIL-2R and TNF alpha serum levels did not appear to change in association with AZT therapy. No changes were observed in the placebo group except that TNF alpha levels appeared to increase after 12 to 16 weeks. These results suggest that AZT administration may have led to reduced HIV P24 antigen, beta 2-microglobulin, neopterin and SCD8 mean levels in these patients.     

Cytokine induction of neopterin production.

The pteridine neopterin is a marker of immunological activation and has been shown to be a useful marker of graft-versus-host disease (GVHD) in bone marrow transplant patients. High levels of both neopterin and interferon-gamma (IFN-gamma) were produced in vitro during mixed lymphocyte responses, which may be considered to be a model of the primary events leading to GVHD. Neopterin was shown to be produced by monocytes in response to stimulation with IFN-gamma, but not other cytokines. However, the interleukins IL-1 alpha, IL-1 beta, IL-2, and tumour necrosis factor (TNF) alpha and beta, but not IL-6, stimulated neopterin production by unfractionated peripheral blood mononuclear cells (PBMC), and culture supernatants from PBMC stimulated with IL-1 alpha, IL-1 beta, IL-2 and IL-6, but not TNF-alpha or TNF-beta induced neopterin production following transfer to fresh monocyte cultures. It therefore appears that cytokines may generate neopterin by induction of IFN-gamma, by synergy with low levels of induced IFN-gamma, or by non-IFN-gamma-dependent mechanisms.     

Epidermal tumour necrosis factor alpha and interleukin 6-like activities in AIDS-related Kaposi's sarcoma. An immunohistological study

Biopsies from 6 patients with AIDS and Kaposi's sarcoma (KS) in the tumour stage, and 6 healthy controls, were immunohistologically examined for the presence of tissue-bound tumour necrosis factor alpha (TNF alpha) and interleukin 6 (IL-6) in the skin. TNF alpha was demonstrated using specific polyclonal antiserum to human recombinant TNF alpha. IL-6 was visualized indirectly using a polyclonal antiserum to partially purified human crude supernatants of activated human blood monocytes, followed by absorption with recombinant human IL-6. The cytokines were found identically located in epidermal cell membranes in stratum granulosum and spinosum of the epidermis from unaffected skin in both AIDS patients and in controls. Biopsies from KS elements showed markedly increased epidermal staining for both TNF delta and IL-6. It was not possible to detect TNF alpha or IL6 in the endothelial cells of the tumour. The observation of increased amounts of epidermal-bound TNF alpha and IL-6 in AIDS-related KS elements supplements previous studies indicating that the skin plays an active immunoinflammatory role in patients with AIDS.     

HIV-1-Antigenämie und T-Zell-Aktivierung bei HIV-1-infizierten Patienten

Summary In order to study a supposed association between T-cell activation in vivo and HIV-1-antigenemia in HIV-1-infected patients, the detection of p24-antigen in sera was correlated to serum levels of beta-2-microglobulin and C1q-binding immune complexes. Anti-p24-antibodies and the urinary excretion of neopterin were also analysed.In 24 of 80 patients (30%) p24-antigen could be detected, and in 15 of 59 (25.4%) there was a loss of anti-p24-antibodies. Tests revealed elevated serum levels of beta-2-microglobulin in 58 of 80 patients (72.5%), elevated levels of C1q-binding immune complexes in 15 of 66 (22.7%), and increased excretion of neopterin in 52 of 60 (86.7%). Detection of p24-antigen, loss of antip24-antibodies, serum levels of beta-2-microglobulin, and urinary excretion of neopterin were significantly correlated to advanced stages of HIV-1 infection.Patients with p24-antigen in the serum showed significantly more frequently elevated serum levels of beta-2-microglobulin and no significant association with increased urinary excretion of neopterin.Because of the high proportion of patients with elevated serum levels of beta-2-microglobulin and increased excretion of urinary neopterin in the absence of detectable p24-antigen in serum, we could not correlate HIV-1-antigenemia to T-cell activation in vivo.

---

Abkürzungen AIDS Acquired Immunodeficiency Syndrome - CD Cluster of differentiation - HIV Human Immunodeficiency Virus - PHA Phythämagglutinin - WR Walter-Reed-Stadium     

Dual neuroendocrine glands: sensitivity of the pineal gland to hormonal feedback

Numerous studies have tried to determine whether alterations in the hormonal content of the plasma would modify pineal function. Recent evidence has indicated that the pineal is relatively insensitive to alterations in plasma hormone concentration, as contrasted with the neuroendocrine hypothalamus which is very responsive to hormonal feedback. Therefore, two types of neuroendocrine glands appear to exist based on their ability to respond to hormonal feedback. The first type of neuroendocrine gland, exemplified by the neuroendocrine portion of the hypothalamus, is extremely sensitive to hormonal modulation and is concerned with maintaining the endogenous balance of plasma hormones. The second type of neuroendocrine gland, exemplified by the pineal gland, is principally responsible for converting its neural input, usually a environmental stimulus, into a hormonal messenger, irrespective of plasma hormone levels. These two types of neuroendocrine glands would act in synchrony to maintain homeostasis throughout a variety of external conditions.     

Psychosocial stress affects pineal function in the tree shrew (Tupaia belangeri)

Using a recently developed commercially available radioimmunoassay the concentration of the principal melatonin metabolite 6-sulfatoxymelatonin (aMT6s) in the morning urine of male tree shrews was determined. Chronic social confrontation elicited a drastic increase of aMT6s excretion in subordinate tree shrews, whereas there was a tendency to reduced excretion of the melatonin metabolite in dominant animals. These results substantiate the function of the pineal gland in transforming stimuli from the social environment to endocrine information and, therefore, are indicative for the relevant role the gland may play in the physiological reactions to chronic psychosocial stress.     

Dose-dependent increase in plasma interleukin-6 after recombinant tumour necrosis factor infusion in humans.

Several studies have shown that the cytokine interleukin-6 (IL-6) is produced in response to tumour necrosis factor (TNF) in vitro. This study examines the in vivo relation between these two cytokines with assays of plasma IL-6 and TNF levels in subjects with chronic hepatitis B undergoing immunomodulatory therapy with recombinant TNF (rTNF). Plasma IL-6 was detected from 20 min after rTNF infusion with levels peaking after 2-3 h and levels correlated with the dose of rTNF administered (r = 0.67, P = 0.004). Peak levels of IL-6 (mean 295, range 266-297 ng/l) were lower than those seen in certain disease states despite the very high peak levels of rTNF (mean 11,750, range 5623-18,620 ng/l). These findings suggest that the very high levels of IL-6 found in certain disease states are not purely the result of circulating TNF. Other factors such as endotoxin or other cytokines may also play a role in determining levels of plasma IL-6.     

Gamma interferon is dispensable for neopterin production in vivo

Previous studies have indicated that neopterin is synthesized in vitro by human monocyte-derived macrophages and dendritic cells upon stimulation with gamma interferon (IFN-gamma). Neopterin production under specific conditions in vitro has also been obtained upon stimulation with IFN-alpha and/or IFN-beta. However, it is unknown if any IFN-gamma-independent neopterin synthesis is possible in vivo. In the present study we investigated the serum neopterin concentrations in patients affected by the syndrome of Mendelian susceptibility to mycobacterial disease (MSMD). Indeed, this syndrome is characterized by deeply impaired or absent IFN-gamma production or function due to severe mutations in molecules involved in IFN-gamma/interleukin-12 (IL-12)/IL-23-dependent pathway. Serum neopterin levels were measured by an enzyme-linked immunosorbent assay in 27 patients with MSMD. We found that serum neopterin levels are elevated in the complete absence of IFN-gamma activity due either to a complete deficiency of its receptor or to deleterious mutations of IL-12 or its receptor. These data clearly indicate that, as reported from in vitro studies, other stimuli are able to induce neopterin synthesis in vivo. Consequently, neopterin cannot be used as means of diagnosis of MSMD due to IFN-gamma-, IL-12-, and IL-23-dependent pathway defects.     

T-Helper 2 Type Cytokine and Soluble Interleukin-2 Receptor Levels in Seminal Plasma of Infertile Men

PROBLEM: The role of cell-mediated immunity (CMI) in unexplained male infertility and impaired sperm function has been explored. METHOD OF STUDY: The presence of cytokines, namely, interleukin-4 (IL-4), interleukin-6 (IL-6), and the soluble interleukin-2 receptor (SIL-2R), was investigated in seminal plasma of 18 fertile and 20 infertile subjects, using specific enzyme-linked immunoadsorbent assays. RESULTS: IL-4 was not detected. SIL-2R was detected, but the concentration difference between the fertile and infertile group was not significant. IL-6 was detected with significantly higher levels in the infertile group compared to the fertile group. IL-6 levels in seminal plasma correlated positively with leukocyte count and negatively with sperm count, motility, and morphology. CONCLUSIONS: These findings show: a) a lack of IL-4 in seminal plasma; b) similar SIL-2R levels in fertile and infertile seminal plasma; c) increased IL-6 secretion in seminal plasma of infertile subjects; and d) specific correlations of IL-6 with the main semen parameters.     

Cytokines in symptomatic asthma airways.

To determine whether cytokines are generated in vivo in subjects with asthma, we have measured cytokine levels (tumor necrosis factor [TNF], granulocyte-macrophage-colony-stimulating factor [GM-CSF], interleukin [IL]-1 alpha, IL-1 beta, IL-2, IL-4, and IL-6) in the airways of subjects with symptomatic (N = 24) and asymptomatic (N = 9) asthma with immunoassays (GM-CSF, IL-1 alpha, IL-1 beta, IL-2, and IL-4) or bioassays (TNF and IL-6) and the polymerase chain reaction (IL-1 beta and TNF). Significant levels of TNF (578 +/- 917 pg/ml versus 24 +/- 29 pg/ml) (p = 0.01), GM-CSF (24 +/- 41 pg/ml versus less than 8 pg/ml) (p = 0.02), and IL-6 (225 +/- 327 pg/ml versus 7 +/- 12 pg/ml) (p = 0.01), but not IL-1 alpha or IL-4, were detected in the bronchoalveolar lavage fluid (BALF) of patients with symptomatic compared with BALF of patients with asymptomatic asthma. Levels of IL-1 beta (266 +/- 270 pg/ml versus less than 20 pg/ml) (p = 0.001) and IL-2 (1.4 +/- 2.8 ng/ml versus less than 0.3 ng/ml) (p = 0.05) in BALF in patients with symptomatic compared with that in BALF levels in patients with asymptomatic asthma suggested activation of alveolar macrophages and T cells. Thus, in episodes of asthma, several cytokines, including TNF, GM-CSF, IL-1 beta, IL-2, and IL-6 are detectable in BALF.     

Maternal serum levels of pro-inflammatory cytokines in missed and threatened abortion

PROBLEM: A study of association between pro-inflammatory cytokines, and missed and threatened abortions with good outcome has been performed. METHOD OF STUDY: The presence of pro-inflammatory cytokines, namely interleukin (IL)-8 and IL-12 and the soluble interleukin-2 receptor (SIL-2R) was investigated in maternal serum of 12 patients with threatened abortion twice (at admission and discharge), 14 patients with missed abortion, 14 women with healthy first-trimester pregnancy, and 14 normal non-pregnant women, using specific enzyme-linked immunosorbent assays. RESULTS: SIL-2R and, in particular, IL-12 was detected with significantly higher levels in missed abortion group compared with all other groups. IL-8 was detected with no significant difference among all the groups studied. CONCLUSIONS: In spite of caution due to the small sizes of the subject samples, these results support a role of the immune system in the first trimester pregnancy and hypothesize that missed abortion may be associated with an enhanced Th1 reactivity, whereas threatened abortion with good outcome resembles the normal pregnancy with a non-enhanced Th1 reactivity.     

Neopterin-induced expression of intercellular adhesion molecule-1 (ICAM-1) in type II-like alveolar epithelial cells

In order to examine the regulatory effects of major Th1-derived cytokines, such as IL-12, and Th2 cytokines, IL-4 and IL-10, on the formation of neopterin and degradation of tryptophan, two metabolic pathways induced by interferon-gamma (IFN-gamma) in human monocytes/macrophages, we investigated the human monocytic cell line THP-1, primary human macrophages, and peripheral blood mononuclear cells (PBMC). Neopterin formation and tryptophan degradation were induced similarly by IFN-gamma in all three cell types investigated, but the effects of interleukins were different between THP-1, primary macrophages and PBMC. In PBMC, but not in THP-1 cells and primary macrophages, IL-12 was found to be additive to the effects of IFN-gamma to superinduce neopterin formation and tryptophan degradation. IL-4 and IL-10 reduced the effects of IFN-gamma on monocytic cells, and both cytokines were additively antagonistic to IFN-gamma in PBMC and THP-1 cells. Finally, on preincubation, but not on addition of IL-12, the effects of IL-4 and IL-10 on PBMC could be abrogated, whereas no such effect was seen in THP-1 cells. The results show that IL-12 up-regulates neopterin formation and tryptophan degradation by inducing additional IFN-gamma production by Th1 cells, while a direct effect of IL-12 on monocytes/macrophages appears to be absent. Similarly, IL-4 and IL-10 inhibit neopterin production and tryptophan degradation in PBMC by down-regulating Th1-type cytokine production and possibly also via direct deactivation of IFN-gamma effects towards monocytes/macrophages. The results clearly show how Th1 cell-mediated immunity may be up- or down-regulated by endogenous cytokine production.     

Differential priming effects of proinflammatory cytokines on human neutrophil oxidative burst in response to bacterial N-formyl peptides.

Cytokines such as tumor necrosis factor alpha (TNF-alpha), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin 8 (IL-8), IL-6, IL-1 alpha, and IL-1 beta produced during the immune and inflammatory responses to bacterial stimuli have been reported to interact with polymorphonuclear neutrophil (PMN) activities. However, contradictory findings on their direct and priming effects on the PMN oxidative burst, which is essential for bacterial killing, have been reported. We have used a flow cytometry method to study the effects of these cytokines on the oxidative burst of PMN in whole blood to avoid PMN activation related to isolation procedures. None of the cytokines tested directly activated the PMN oxidative burst, but they did have differential priming effects on the oxidative burst in response to bacterial N-formyl peptides. TNF, GM-CSF, and IL-8 strongly primed a subpopulation of PMN to produce H2O2 in response to N-formyl-methionyl-leucyl-phenylalanine (FMLP), while IL-1 alpha, IL-1 beta, and IL-6 failed to do so. Furthermore, the addition of TNF, GM-CSF, or IL-8 to whole blood increased the capacity of a subpopulation of PMN to bind N-formyl peptides, a phenomenon that could account, at least in part, for the strong H2O2 production in response to FMLP after priming by the cytokines. The size of the primed hyperresponsive subpopulation was greater after priming with TNF or GM-CSF than after priming with IL-8. However, GM-CSF, TNF, and IL-8 at suboptimal concentrations cooperated in the induction of a subpopulation hyperresponsive to FMLP. These results show that, of the various proinflammatory cytokines tested, TNF, GM-CSF, and IL-8 strongly prime the PMN oxidative burst in response to bacterial peptides in whole blood and suggest that these cytokines may play a critical role in bacterial killing in vivo.     

Effect of an Extract Based on the Medicinal Mushroom Agaricus blazei Murill on Release of Cytokines, Chemokines and Leukocyte Growth Factors in Human Blood Ex Vivo and In Vivo

An immunostimulatory extract based on the medicinal mushroom Agaricus blazei Murill (AbM) has been shown to stimulate mononuclear phagocytes in vitro to produce pro-inflammatory cytokines, and to protect against lethal peritonitis in mice. The present aim was to study the effect of AbM on release of several cytokines in human whole blood both after stimulation ex vivo and in vivo after oral intake over several days in healthy volunteers. The 17 signal substances examined were; T helper 1 (Th1) cytokines [interleukin (IL)-2, interferon (IFN)-γ and IL-12], T helper 2 cytokines (IL-4, IL-5 and IL-13), pleiotropic (IL-7, IL-17), pro-inflammatory [IL-1β, IL-6, tumour necrosis factor (TNF)-α (mainly produced by Th1 cells)] – and anti-inflammatory (IL-10) cytokines, chemokines [IL-8, macrophage inhibitory protein (MIP)-1β and monocyte chemoattractant protein (MCP)-1] and leukocyte growth factors [granulocyte colony-stimulating factor (G-CSF), granulocyte/macrophage colony stimulating factor]. After stimulation of whole blood ex vivo with 0.5–5.0% of a mushroom extract, AndoSan™ mainly containing AbM , there was a dose-dependent increase in all the cytokines studied, ranging from two to 399-fold (TNF-α). However, in vivo in the eight volunteers who completed the daily intake (60 ml) of this AbM extract for 12 days, a significant reduction was observed in levels of IL-1β (97%), TNF-α (84%), IL-17 (50%) and IL-2 (46%). Although not significant, there was a trend towards reduced levels for IL-8, IFN-γ and G-CSF, whilst those of the remaining nine cytokines tested, were unaltered. The discrepant results on cytokine release ex vivo and in vivo may partly be explained by the antioxidant activity of AbM in vivo and limited absorption of its large, complex and bioactive β-glucans across the intestinal mucosa to the reticuloendothelial system and blood.     

Immunological interactions in different forms of coronary heart disease

The study included measurement of serum levels of IL-1beta, IL-2, IL-6, IL-8, and TNF-alpha, as well as the expression of mRNA IL-1beta, IL-2, IL-6, and TGfb1 in the vascular wall of patients with coronary atherosclerosis (angina, myocardial infarction). IL-1beta, IL-2, IL-6, IL-8, and TNF-alpha serum levels in patients with coronary atherosclerosis were found to significantly higher than those in healthy individuals (control group). Detection of IL-1beta, IL-2, IL-6, and TGFb1 in tissues revealed mRNA of the cytokines under study in radial artery wall. The main aortic cytokine was found to be IL-2 (7 samples out of 8); the main cytokines in peripheral arteries were IL-1beta and IL-6 (5 samples out of 8). The results show that elevation of IL-1beta, IL-2, and IL-8 in patients with coronary atherosclerosis demonstrates an immunoinflammatory nature of the disease; the detection of dissimilar cytokines in tissue samples reflects not only different degree of vessel involvement, but also a phase character of the process.     

Cytokine expression in labial salivary glands from patients with primary Sj?gren's syndrome.

The presence and distribution of 7 cytokines was examined immunohistologically in labial salivary gland (LSG) specimens from patients with primary Sj?gren's syndrome (SS) and control subjects. The cytokines interleukin (IL)-1 beta IL-6, tumor necrosis factor (TNF) alpha and interferon (IFN) gamma were identified in defined parts of LSG from patients but not in the corresponding parts of control glands: (a) LSG acinar epithelium expressed IL-1 beta, (b) blood vessels located in both normal LSG stroma and within lymphocytic infiltrates expressed IL-1 beta, IL-6 and IFN gamma, and (c) lymphocytic infiltrates expressed IL-1 beta, IL-6 and TNF alpha. All four cytokines were expressed by salivary ducts within both patient and control specimens, but with generally greater intensity in patients. IL-1 alpha, IL-4 and TNF beta (lymphotoxin) could not be detected in any of the specimens from patients or controls. The locations of cytokines in LSG suggests possible mechanisms of immunologically mediated parenchymal damage in primary SS.     

黄芪多糖对荷瘤小鼠IL-2、IL-6、IL-12和TNF-α水平的影响

目的：研究黄芪多糖对荷瘤小鼠肿瘤生长及细胞因子水平的影响。方法：建立小鼠肝癌H22和小鼠肉瘤S180移植性肿瘤模型,检测黄芪多糖的体内抗肿瘤活性;采用ELISA法检测黄芪多糖对荷瘤小鼠血清中白细胞介素-2（IL-2）、白细胞介素-6（IL-6）、白细胞介素-12（IL-12）、肿瘤坏死因子-α（TNF-α）水平的影响。结果：黄芪多糖在50,100mg·kg^-1时,对小鼠肝癌H22的抑瘤率分别为32．84％,45．09％,对小鼠肉瘤S180的押瘤率分别为36．55％,50．35％,且能提高荷瘤小鼠的脾指数和胸腺指数;黄芪多糖能提高荷瘤小鼠血清中细胞因子IL-2、IL-6、IL-12和TNF-α的水平。结论：黄芪多糖具有明显的体内抗肿瘤活性,其机制可能与增强机体的免疫功能有关。     

Neopterin augmentation of tumor necrosis factor production

Gamma interferon (gamma-IFN), lipopolysaccharide (LPS)-gamma or interleukin-2 (IL-2)-induced tumor necrosis factor alpha (TNF alpha) production by both macrophages and peripheral blood mononuclear cells (PBMC), was increased in the presence of neopterin. Addition of neopterin caused an increased level of TNF alpha, but did not affect the kinetics of the TNF alpha production, which showed peak levels of cytotoxic activity 4 h after stimulatory treatment. Using anticytokine antibodies, we concluded that the neopterin effect was mainly gamma-IFN mediated, and only slightly affected by anti IL-2 receptor antibodies. The neopterin augmented TNF alpha production can be attributed to an immunological role for neopterin in the enhancement of cell-mediated immune (CMI) response.     

Reduction of IL-12 p40 production in activated monocytes after exposure to diesel exhaust particles

BACKGROUND: A reduction of IL-12 production by lung macrophages may partly explain the presumed adjuvant effect of diesel exhaust particles (DEP) in allergy and asthma. IL-12 stimulates T helper type 1 (Th1) lymphocytes, which inhibit Th2 cells via Th1-specific cytokines. The aim of this study was to investigate the influence of DEP on the production of IL-12 p40 in lipopolysaccharide (LPS)-activated monocytes. METHODS: The human monocytic cell line Mono-Mac-6 was stimulated with LPS (200 ng/ml) and grown with DEP (0-200 microg/ml) for 0, 6 or 24 h. IL-12 p40 and the pro-inflammatory cytokine TNF were analysed in the cell supernatants by ELISA and a cell assay, respectively. RESULTS: Levels of IL-12 p40 correlated inversely with the DEP exposure concentrations, whereas TNF increased in parallel to the DEP concentrations. At a DEP concentration of 200 microg/ml, the amount of IL-12 p40 was 35% of that observed without DEP. The corresponding TNF value was 230% of the control. Reduced viability, binding of cytokines to DEP or endotoxin in the DEP samples cannot fully explain the changes in the concentrations of these two cytokines. CONCLUSION: DEP seem to inhibit the production of IL-12 p40 and stimulate that of TNF in activated monocytes. This may partly explain the presumed adjuvant effect of DEP in atopy; by altering the Th1/Th2 balance via down-regulation of IL-12, the Th2 response characteristic of allergy and asthma may be favoured.     

Gamma Interferon Is Dispensable for Neopterin Production In Vivo

Previous studies have indicated that neopterin is synthesized in vitro by human monocyte-derived macrophages and dendritic cells upon stimulation with gamma interferon (IFN-γ). Neopterin production under specific conditions in vitro has also been obtained upon stimulation with IFN-α and/or IFN-β. However, it is unknown if any IFN-γ-independent neopterin synthesis is possible in vivo. In the present study we investigated the serum neopterin concentrations in patients affected by the syndrome of Mendelian susceptibility to mycobacterial disease (MSMD). Indeed, this syndrome is characterized by deeply impaired or absent IFN-γ production or function due to severe mutations in molecules involved in IFN-γ/interleukin-12 (IL-12)/IL-23-dependent pathway. Serum neopterin levels were measured by an enzyme-linked immunosorbent assay in 27 patients with MSMD. We found that serum neopterin levels are elevated in the complete absence of IFN-γ activity due either to a complete deficiency of its receptor or to deleterious mutations of IL-12 or its receptor. These data clearly indicate that, as reported from in vitro studies, other stimuli are able to induce neopterin synthesis in vivo. Consequently, neopterin cannot be used as means of diagnosis of MSMD due to IFN-γ-, IL-12-, and IL-23-dependent pathway defects.