Activation of human dendritic cells by bacillus Calmette-Guerin

PURPOSE

Dendritic cells are the most potent antigen presenting cells capable of initiating antitumor immune responses. We previously showed that bacillus Calmette-Guerin (BCG) stimulates cultured human dendritic cells. We extended these studies and tested the ability of cultured human dendritic cells to express interleukin IL-8 in response to BCG. We also investigated the T cell stimulatory potential of BCG treated dendritic cells in mixed leukocyte reactions.

MATERIALS AND METHODS

Dendritic cells were obtained by culturing plastic adherent mononuclear cells from peripheral blood for 6 days in the presence of granulocyte-macrophage colony-stimulating factor and IL-4. Spontaneous and BCG stimulated IL-8 protein release into culture supernatants was measured by a quantitative immunoassay. IL-8 gene transcription was assessed by reverse transcription-polymerase chain reaction. Untreated and BCG exposed dendritic cells were compared as stimulators of allogeneic T cell proliferation, measured as [3H]thymidine incorporation.

RESULTS

BCG stimulated IL-8 messenger ribonucleic acid expression and IL-8 protein release. IL-8 secretion occurred in a dose and time dependent fashion. BCG induced IL-8 release was further enhanced in the presence of indomethacin. BCG treated dendritic cells were much more potent T cell stimulators than untreated dendritic cells.

CONCLUSIONS

These data demonstrate that BCG enhances the production of IL-8, a potent chemokine of T cells and granulocytes, as well as the T cell stimulatory potential of human dendritic cells.

Release of chemoattractants for human monocytes from endothelial cells by interaction with neutrophils

OBJECTIVE

The release of monocyte chemoattractant protein-1 (MCP-1) in the vessel wall may lead to accumulation of monocytes in the subendothelial space. The role of neutrophils (PMNL) in the initiation of this process is unknown. We tested whether PMNL are able to induce the production and release of MCP-1 in endothelial cells.

METHODS

PMNL were allowed to interact with human umbilical vein endothelial cell (HUVEC) monolayers in culture. Culture media were collected and assessed for chemotactic activity on mononuclear leukocytes (MNC) or purified monocytes in a modified Boyden chamber assay. Additionally, MCP-1 levels in supernatants were quantified by ELISA.

RESULTS

Media from unstimulated HUVEC culture supernatants induced a slight increase (1.2-fold) of MNC and purified monocyte chemotaxis, which was significantly augmented by addition of PMNL for 1 h (1.4-fold; P < 0.05). The increase in chemotaxis was time- and dose-dependent and could be blocked by an anti-MCP-1 monoclonal antibody. Media obtained after coculture of PMNL and HUVEC for 1-5 h contained increased amounts of MCP-1 as measured by ELISA; addition of cycloheximide abolished this response.

CONCLUSIONS

Interaction of PMNL with endothelium induces the release of functionally active MCP-1 suggesting that in the vascular wall, PMNL may play a role in the recruitment of MNC.

Differential deactivation of human dendritic cells by endotoxin desensitization: role of tumor necrosis factor-alpha and prostaglandin E2

The endotoxin (lipopolysaccharide)-induced cytokine response is followed by a state of unresponsiveness to lipopolysaccharide (LPS) referred to as LPS tolerance or endotoxin desensitization. LPS tolerance, which can be experimentally induced in vitro and in vivo, is also known to occur in septic disease. Here, we evaluated whether dendritic cells (DC), the most potent antigen-presenting cells, are also subject to this phenomenon. Single doses of LPS added at the initiation of DC culture inhibited in a dose-dependent fashion the production of tumor necrosis factor-alpha (TNF-alpha), interleukin-10 (IL-10), and IL-12, but not the production of IL-8, in response to a second LPS challenge in day-5 DC. In addition, the LPS-induced expression of the CD83 maturation antigen was inhibited in these cells. Moreover, the endocytic activity of DC generated in the presence of LPS was dramatically reduced. DC desensitized with LPS were potent stimulators of T-cell proliferation but poor inducers of interferon-gamma (IFN-gamma) production in the allogeneic mixed leukocyte reaction. TNF-alpha and prostaglandin E2, two major products of LPS stimulation, could replace LPS for the induction of tolerance to LPS. Moreover, treatment of desensitized DC with TNF-alpha plus prostaglandin E2 fully restored CD83 expression and partially restored IL-12 production as well as the IFN-gamma-inducing activity of DC in the mixed leukocyte reaction. Our data show that human DC are highly susceptible to the induction of LPS tolerance, which seems to be a state of differential deactivation in which some functions are impaired whereas others are retained. Tolerization at the level of the professional antigen-presenting cell by inflammatory mediators may play an important role in septic disease and in the origin of cancers associated with chronic inflammation.

Ascitic interleukin-12 is an independent prognostic factor in ovarian cancer

PURPOSE

The clinical impact of endogenous cytokines supplied with deterministic properties in the generation of either T helper (Th)1 -type or Th2-type immune response was investigated in patients with ovarian cancer. Whereas interleukin (IL)- 12 initiates the differentiation of naive Th0 cells toward Th1 phenotype, IL-4 and IL-10 mediate the development of Th2-type immunity.

PATIENTS AND METHODS

Cytokines were determined before treatment by means of enzyme-linked immunosorbent assay (ELISA) in ascites fluid and serum of 76 patients with ovarian cancer. Cytokine levels were compared with each other and with standard clinicopathologic parameters. A stepwise logistic regression was calculated to rule out interdependence in the associations of the various variables. Survival analyses were performed with the Kaplan-Meier method and differences in survival were examined according to Mantel and Breslow. Cox proportional hazards analysis was used to identify independent prognostic factors.

RESULTS

Whereas IL-10 and IL-12 were detectable in all ascites-fluid samples, IL-4 was measurable in only 43% of the specimens. With the exception of neopterin, macrophage colony-stimulating factor (M-CSF), and IL-4, determined cytokine levels were significantly elevated in ascites fluid compared with serum (P < .01). In univariate analyses, high ascitic-fluid concentrations of either neopterin, tumor necrosis factor-alpha (TNF-alpha), or IL-12 were associated with poor disease-free (P < .005) and overall (P < .01) survival. Multivariate Cox regression analysis showed ascitic-fluid IL-12 levels to be the only immunologic variable that retained independent prognostic significance (P < .03 for disease-free and P < .01 for overall survival), together with residual disease, Fédération Internationale de Gynécologie et d'Obstétrique (FIGO)-stage, and patient age.

CONCLUSION

In ovarian cancer, high ascitic-fluid IL-12 levels, which may indicate a local Th1-generated immune response, are associated with disease progression.

Urticaria pigmentosa: a clinical, hematopathologic, and serologic study of 30 adults

Urticaria pigmentosa (UP) is the most common form of cutaneous mastocytosis and may be associated with systemic involvement, most often of the bone marrow. The incidence of systemic involvement is not yet well established, however. To address this question, we subjected a group of 30 adults with histologically proved UP to a retrospective study that included history, physical examination, laboratory tests including cytokine measurements, radiologic examinations, and bone marrow biopsies. The most frequently associated clinical symptoms were recurrent flush episodes in 16 of 30 patients, alcohol intolerance in 13, pruritus in 10, and gastrointestinal problems in 11 (recurrent diarrhea, 8 patients; gastritis, 2 patients; and history of peptic ulcer, 1 patient). Of the 30 patients, 18 (60%) had mast cell infiltrates of the bone marrow (nodular type, 10 patients; diffuse interstitial type, 8 patients). Bone marrow involvement was not correlated with massive cutaneous mast cell infiltration, clinically or histologically, or with the incidence of clinical symptoms and associated hematologic disorders. None of the patients had experienced progression of clinical symptoms, skin or organ involvement, or development of hematologic malignant neoplasms since UP was first diagnosed (10 years on average). Urticaria pigmentosa was found associated with mast cell infiltration of the bone marrow in 18 patients (60%). However, bone marrow involvement does not seem to predict adverse clinical course.

Induction of arachidonic acid metabolite release by human fibroblasts in proliferative vitreoretinopathy

Proliferative vitreoretinopathy is a severe ocular disorder characterized by unwanted proliferation of cells and excessive production of fibrous tissue, which leads to the formation of cellular membranes on the surface of the retina and in the vitreous. Proliferative vitreoretinopathy is the most common cause of failure in retinal reattachment surgery, approximately occurring in one out of ten operated eyes. Proliferation of retinal pigment epithelial cells and fibroblasts is a cornerstone in the pathogenesis of proliferative vitreoretinopathy. An in vitro-proliferation assay showed previously that intraocular fluid from patients with proliferative vitreoretinopathy is potently effective in stimulating proliferation of human fibroblasts. Here we show that exposure of human fibroblasts to vitreous fluids from patients with proliferative vitreoretinopathy causes a rapid and sustained increase in arachidonic acid metabolite release as measured by competitive enzyme-immunoassay. The findings implicate prostaglandin E2 as a contributor to enhanced intraocular fibrosis in proliferative vitreoretinopathy. As prostaglandin E2 is a mediator of continuous aqueous-blood retinal barrier breakdown in this severe disease, cycclooxygenase inhibitors such as acetylsalicylic acid, which was successfully used in this study for blocking the effect of intraocular fluid, may be useful agents in targeting the progression of intraocular fibrosis.

Endogenous serum thrombopoietin concentrations in patients with myelodysplastic syndromes

Prognosis in patients with myelodysplastic syndromes (MDS) is closely correlated with cytopenia. To date, no factor is available which is able to reliably stimulate megakaryopoiesis in vivo. Recently, the ligand of the mpl receptor was cloned and found to be thrombopoietin (TPO). We measured endogenous TPO serum levels in 69 patients suffering from MDS using an TPO receptor-based ELISA. Twenty-six of the patients suffered from refractory anemia (RA), 12 from RA with excess of blasts (RAEB), 25 from RAEB in transition (RAEBt), and six from chronic myelomonocytic leukemia (CMML). This assay uses a chimeric molecule consisting of the human TPO receptor fused to the Fc portion of human IgG as the capture reagent. Biotinylated antibody to TPO IgG was used for detection and the lower detection limit in serum was found to be 160 pg/ml. Samples obtained from healthy individuals with a normal platelet number were shown to be below detectable levels. In patients with RA, high endogenous serum TPO concentrations correlated with low platelet count and significantly elevated TPO concentrations were only found when megakaryopoiesis was absent or decreased in the bone marrow. This correlation was not detected in RAEB and RAEBt patients and no detectable TPO serum concentrations were found in six CMML patients whether they showed decreased or normal platelet count. Our data show that endogenous TPO production is upregulated by decreased circulating platelet count only in patients with refractory anemia. In the more advanced stages of MDS where the leukemic clone has further progressed, an inadequate TPO response occurs, possibly due to overexpression of the mpl receptor by the malignant clone.

About 8-hour variation of circulating human endothelin-1

Plasma endothelin-1 (ET-1) and cortisol were measured around the clock at hourly intervals on 7 clinically healthy, diurnally active, nocturnally resting subjects 22-27 years of age. The circadian rhythm in cortisol is demonstrated for each subject (p < or = 0.020) as well as on a group basis (p = 0.002), peaking in the morning. By contrast, the circadian variation of ET-1 is statistically significant in only one of the subjects, and it is not detected for the group as a whole (p > 0.20). Instead, ET-1 is characterized by an about 8-h component (p < 0.001) that is not found for cortisol.

[Melatonin and coronary heart disease]

The observation of raised nocturnal urinary norepinephrine excretion in patients with coronary heart disease (CHD), together with results of animal experiments showing a suppression of sympathetic activity by melatonin, were the reasons for this investigation. In 15 patients with CHD and 10 controls the concentrations of serum melatonin, serotonin and N-acetylserotonin were determined in samples gained by venopuncture at 14.00 h and 02.00 h. The melatonin secretion was significantly lower at 02.00 h in the patients with CHD than in the controls. Moreover the serotonin concentration was significantly lower at 14.00 h in the patients with CHD, and somewhat, but not significantly, lower at 02.00 h than in the controls. On the other hand, the serum concentrations of N-acetylserotonin showed a tendency towards higher levels in the CHD patients than in the controls. The causes and consequences of the diminished secretion during the night in patients with CHD are discussed.

The phosphatidyl-myo-inositol anchor of the lipoarabinomannans from Mycobacterium bovis bacillus Calmette Guérin. Heterogeneity, structure, and role in the regulation of cytokine secretion

Lipoarabinomannans are major mycobacterial antigens capable of modulating the host immune response; however, the molecular basis underlying the diversity of their immunological properties remain an open question. In this study a new extraction and purification approach was successfully applied to isolate ManLAMs (lipoarabinomannans with mannosyl extensions) from bacillus Calmette Guérin leading to the obtention of two types of ManLAMs namely parietal and cellular. Structurally, they were found to differ by the percentage of mannooligosaccharide caps, 76 and 48%, respectively, and also, thanks to a new analytical method, by the structure of the phosphatidyl-myo-inositol anchor lipid moiety. A novel fatty acid in the mycobacterium genus assigned to a 12-O-(methoxypropanoyl)-12-hydroxystearic acid was the only fatty acid esterifying C-1 of the glycerol residue of the parietal ManLAMs, while the phosphatidyl unit of the cellular ManLAMs showed a large heterogeneity due to a combination of palmitic and tuberculostearic acid. Finally, parietal and cellular ManLAMs were found to differentially affect interleukin-8 and tumor necrosis factor-alpha secretion from human dendritic cells. We show that parietal but not cellular ManLAMs were able to stimulate tumor necrosis factor-alpha secretion from dendritic cells. From these studies we propose that the 1-[12-O-(methoxypropanoyl)-12-hydroxystearoyl]-sn-glycerol part is the major cytokine-regulating component of the ManLAMs. It seems likely that modification of the ManLAM lipid part, which may occur in hostile environments, could regulate macrophagic mycobacterial survival by altering cytokine stimulation.

A comparative study of the in vitro immunomodulatory activity of human intact immunoglobulin (7S IVIG), F(ab')2 fragments (5S IVIG) and Fc fragments. Evidence for post-transcriptional IL-2 modulation

During the past few decades intravenous immunoglobulin (IVIG) has been used successfully in the treatment of various immunoregulatory disorders. Treatment results have been attributed to immunomodulation mainly via Fc receptors or by anti-idiotypic antibodies to disease-causing autoantibodies. From the present study it is clearly evident that 7S IVIG (intact immunoglobulin) as well as 5S IVIG [F(ab')2 fragments] and Fc fragments have a potent immunomodulatory capacity. We demonstrate that mainly 7S IVIG inhibits alloantigen-induced T-cell proliferation and generation of cytotoxic T lymphocytes. Reduced interleukin-2 (IL-2) protein levels in culture supernatants of IVIG-supplemented mixed lymphocyte reactions (MLR) but unchanged IL-2 mRNA levels strongly argue in favour of a post-transcriptional interference of IVIG with cytokines and/or cytokine production. Interferon-gamma (IFN-gamma), soluble IL-2 receptor (sIL-2R) and monokines such as IL-1 beta, IL-6, IFN-alpha and tumour necrosis factor (TNF-alpha) were not affected by IVIG supplementation to MLR. Fc fragments were superior to F(ab')2-containing IVIG (5S and 7S IVIG) in inhibiting lectin stimulation of peripheral blood mononuclear cells (PBMC), whereas natural killer (NK) cytotoxicity was primarily inhibited by Fc-bearing IVIG (7S IVIG and Fc fragments), suggesting multiple mechanisms of IVIG immunomodulatory activity.

Endogenous interleukin 1 receptor antagonist during human bone marrow transplantation: increased levels during graft-versus-host disease, during infectious complications, and after immunoglobulin therapy

In order to understand in more detail the role of endogenous interleukin 1 receptor antagonist (IL-1ra) during bone marrow transplantation, IL-1ra serum levels of 28 patients undergoing allogeneic (n=25) or autologous (n=3) bone marrow transplantation were measured with a commercially available ELISA. In addition, the impact of intravenous immunoglobulin (IVIG) was evaluated by analyzing IL-1ra serum levels before and 2, 5, and 24 hr after IVIG infusion. IL-1ra measurements revealed a nadir of circulating IL-1ra levels 3-5 days after bone marrow transplantation, with an increase during conditioning and hematological reconstitution. Circulating IL-1ra levels were significantly increased in patients with cytomegalovirus (CMV) disease, CMV reactivation, graft-versus-host disease (GVHD), or fever of unknown origin, when compared with time-matched controls without complications. Highest levels were observed in patients with CMV disease (1922+/-388 pg/ml), followed by patients with CMV reactivation (1575+/-435 pg/ml) and GVHD (1178+/-317 pg/ml). The magnitude of IL-1ra increase in GVHD was related to disease severity. Patients with grade III-IV GVHD developed higher IL-1ra levels than did patients with grade I-II GVHD. Lower but still significantly elevated IL-1ra levels were observed during fever of unknown origin (384+/-87 pg/ml). An increase of IL-1ra serum levels followed the administration of IVIG before transplantation and after hematopoietic reconstitution, but not during aplasia, pointing to the important role of hematopoietic cells in the production of IL-1ra. In conclusion, we show that IL-1ra release is related to conditioning regimen, hematopoietic reconstitution, complications of infectious and alloimmune etiology after bone marrow transplantation, and exogenously administered IVIG.

Bacillus Calmette-Guérin mycobacteria stimulate human blood dendritic cells

Bacillus Calmette-Guérin (BCG) mycobacteria have been used as adjuvant in the active immunotherapy of various human cancers. In addition, dendritic cells, which are the most potent antigen-presenting cells, have been shown to be capable of initiating anti-tumor immune responses. Here we investigated the effects of BCG on dendritic cells cultured from human blood. Addition of BCG resulted in rapid homotypic adhesion of dendritic cells. Moreover, BCG concentrations ranging from 10(4) to 10(6) bacteria/ml enhanced expression of the dendritic-cell-maturation antigen CD83 and of the T-cell co-stimulator CD86 (B7-2) in a dose-dependent manner. Concomitant with the increase of CD83 and CD86 expression, the cells lost the ability to capture soluble antigens, as determined by the exclusion of fluoresceinated Dextran molecules. Strikingly, the same dosages of BCG-bacteria stimulated TNF-alpha-gene transcription and TNF-alpha-protein release from dendritic cells in a dose-dependent fashion. BCG infection of dendritic cells in the presence of a neutralizing antibody directed against TNF-alpha inhibited CD83 expression by more than 50% indicating that the BCG-induced maturation of dendritic cells was at least partially mediated by dendritic-cell-derived TNF-alpha. The finding that BCG activates the most potent antigen-presenting cells reveals a plausible immunological mechanism of the occasionally observed anti-tumor activity of BCG.

Modulatory potential of iron chelation therapy on nitric oxide formation in cerebral malaria

To determine whether iron chelation modulates nitric oxide (NO) formation and cell-mediated immune effector function in children with cerebral malaria, serum concentrations were measured of the stable end products of NO, nitrite and nitrate (NO2-/NO3-), interleukin (IL)-4, -6, and -10, and neopterin in 39 Zambian children enrolled in a placebo-controlled trial of desferrioxamine B and quinine therapy. Mean concentrations of NO2-/NO3- increased significantly over 3 days in children receiving desferrioxamine plus quinine but not in those given placebo and quinine. Neopterin levels declined significantly with placebo but not with desferrioxamine. IL-4 levels increased progressively in the placebo group and ultimately decreased in the desferrioxamine group, but the trends were not statistically significant. IL-6 and IL-10 levels were elevated initially and decreased significantly in both groups over 3 days. These data are consistent with the hypothesis that iron chelation therapy in children with cerebral malaria strengthens Th1-mediated immune effector function involving increased production of NO.

Disturbed immunoendocrine communication via the hypothalamo-pituitary-adrenal axis in murine lupus

Immune reactions and mitogen stimulation of mammals and chickens lead to an increase of glucocorticoid (GC) plasma levels concomitant with the immune response. Interleukin (IL) 1, one of the most important glucocorticoid increasing factors produced by cells of the immune system, acts via the hypothalamo-pituitary-adrenal (HPA) axis. This pattern of immunoendocrine feedback communication is altered in autoimmune disease (AID) and represents a possible site of action for GC therapy. In the present study we investigated the role and possible underlying mechanisms of a disturbed immunoendocrine communication via the HPA axis in murine lupus. We analyzed the response to recombinant human (rhu) IL-1alpha in AID-prone mice [NZB, NZW, (NZB/NZW)F1, MRL/MP-lpr] in comparison to nonautoimmune, normal control mice (Swiss, C3H/HeJ, MRL/MP-+/+) at different levels of the HPA axis. To this end, we quantified the plasma levels of ACTH, corticosterone, and corticosterone-binding globulin (CBG) and determined various pathology parameters for autoimmunity. AID-prone mice produced nearly the same levels of plasma corticosterone after injection of rhu IL-1alpha as normal mice, but had baseline corticosterone levels consistently higher, thus resulting in significantly lower corticosterone increasing ratios. ACTH levels increased after rhu IL-1alpha injection, but there was no clearcut difference in the increasing ratios of AID-prone and normal strains. CBG levels showed no difference. As expected, there was a correlation of pathology parameters for autoimmunity and the altered immunomodulatory response to rhu IL-1alpha per group. On an individual basis, there was no such correlation. In conclusion, our results confirm the existence of a disturbed immunoendocrine communication in AID-prone mice. This disturbance clearly differs from individual to individual and also among different types of AID.

Serum levels of cytokines and secondary messages after T-cell-depleted and non-T-cell-depleted bone marrow transplantation: influence of conditioning and hematopoietic reconstitution

Cytokines are increasingly recognized as important mediators of graft-versus-host disease (GVHD). Measurements of cytokine serum levels in patients with GVHD, and successful prevention and treatment of the disease with the use of cytokine antagonists to either the cytokine or its receptor, are only two of several factors demonstrating the involvement of cytokines in GVHD. To further investigate the role of cytokines in the pathomechanism of acute GVHD, we investigated endogenous serum levels of various cytokines and dependent molecules in sera of 14 patients after T-cell-depleted (TCD) bone marrow transplantation (BMT) and compared the results with those of 12 patients undergoing non-TCD BMT. The effect of various conditioning regimens and of hematopoietic reconstitution on cytokine serum levels was analyzed in detail in these cohorts of patients by measuring interferon (IFN)-gamma, IFN-alpha, tumor necrosis factor-alpha, interleukin-6, neopterin, and beta2-microglobulin. The analyses showed that an increase in IFN-gamma and neopterin serum levels was a specific feature of cyclophosphamide administration and was not observed after other cytostatic drugs or total body irradiation, and that an increase in IFN-gamma, neopterin, beta2-microglobulin, and IFN-alpha release depends on the presence of T cells in the graft. We conclude that significant cytokine serum alterations were noted after TCD BMT as compared with after non-TCD BMT. These alterations, besides depletion of cytotoxic effector cells, might be involved in preventing GVHD after TCD BMT. In addition, more attention should be devoted to the cytokine release-inducing capacity of the conditioning regimen, because such a release might influence the occurrence of transplant-related complications after BMT.

Circulating immunostimulatory protein 90K and soluble interleukin-2-receptor in human ovarian cancer

The tumor-associated antigen 90K is thought to play an important role in cellular immune defense against malignant cells. It is therefore of interest to investigate whether circulating 90K could be used as a prognostic variable in ovarian cancer, and whether this immunostimulatory antigen is related to other parameters known to be involved in the cellular immune response. In the present retrospective study, circulating levels of antigen 90K were measured before primary surgery in 152 ovarian-cancer patients. A very close association between antigen 90K and s-IL-2R concentrations was pointed out in a stepwise logistic regression model. Univariate analysis of overall survival revealed that antigen 90K and s-IL-2R were associated with poor prognosis. In the multivariate Cox regression, however, neither antigen 90K nor s-IL-2R retained independent prognostic significance. Urinary neopterin was shown to be the only independent prognostic variable among the "immunological parameters" investigated. Additionally, residual disease after primary tumor debulking and histopathologic tumor grade were the most prominent clinico-pathologic parameters for the independent prediction of poor clinical outcome in ovarian-cancer patients.

Different effects of interferons, interleukin-1beta and tumor necrosis factor-alpha in normal (OSE) and malignant human ovarian epithelial cells

Ovarian cancer arises mostly from the ovarian surface epithelium. The aim of our study was to compare the effects of cytokines in ovarian surface epithelial (OSE) cells and in ovarian carcinoma cells. Proliferation and expression of surface antigens (CA-125 and classes I and II antigens of the major histocompatibility complex [MHC]) were measured in OSE cells obtained from 7 different patients and 7 ovarian carcinoma cell lines. Proliferation of OSE cells remained unaffected by interferon (IFN)-alpha or IFN-gamma, whereas interleukin-1 (IL-1) and tumor necrosis factor (TNF) increased cell growth. Proliferation of ovarian carcinoma cells was reduced by both types of IFN as well as TNF but was not affected by IL-1. Expression of the tumor marker CA-125 was increased by IFN-gamma in ovarian carcinoma cells but not by any other treatment. None of the cytokines affected CA-125 surface expression in OSE cells. Expression of MHC-I was augmented in OSE and in carcinoma cells by both IFNs but not by the other cytokines. Both types of cell were negative for MHC-II, but IFN-gamma induced its expression in both OSE and carcinoma cells. Significant concentrations of the cytokines evaluated here have been measured in blood and follicular fluid by several authors. The different actions of these cytokines in OSE and carcinoma cells could therefore be important in understanding the role of such molecules in the regulation of physiological and pathological processes in the ovary, such as ovulation or malignant proliferation.

Assessment of endothelial preservation in human cell cultures

BACKGROUND

Impairment of microcirculation due to endothelial cell damage must be considered a limiting factor in organ preservation. The present study aims at a quantitative assessment of preservation-induced injury in cultured human endothelial cells.

METHODS

Monolayer cultures of human umbilical vein endothelial cells were exposed to cold (40 degrees C) hypoxic storage in University of Wisconsin solution, histidine-tryptophane-ketoglutarate solution, Euro-Collins solution, and saline solution. Cellular integrity was evaluated by viable cell count, ultrastructural analysis, and prostacyclin release after 24, 48, and 72 hours of storage and subsequent 6 hours of reincubation in culture medium at 37 degrees C. Expression of intercellular adhesion molecule-1 was investigated after 6, 12, and 24 hours of cold preservation and after 6 hours of rewarming.

RESULTS

Cellular viability was best maintained with University of Wisconsin and histidine-tryptophane-ketoglutarate solutions with no significant reduction of cell count up to 72 hours; Euro-Collins solution and saline solution caused a significant decline in cell numbers after 24 hours (p < 0.05). Morphology was best preserved by University of Wisconsin solution. Prostacyclin values were elevated after 24 hours in Euro-Collins solution and saline solution, after 48 hours in histidine-tryptophane-ketoglutarate, Euro-Collins, and saline solutions, and after 72 hours in Euro-Collins solution (p < 0.05, compared with University of Wisconsin solution). ICAM expression was weak after cold storage (24 hours) in University of Wisconsin solution, moderate after incubation in histidine-tryptophane-ketoglutarate and Euro-Collins solutions and intensive after storage in saline solution. In contrast, rewarming caused intensive expression of intercellular adhesion molecule-1 in all experimental groups as compared with controls, which showed baseline expression at any time.

CONCLUSIONS

From our results we conclude that in this model cellular integrity is best protected by University of Wisconsin solution, increased prostacyclin release is consistent with morphologic alterations and intercellular adhesion molecule-1 expression is clearly up-regulated in endothelial cells under reperfusion conditions after cold hypoxic storage.

In vitro stimulation of erythropoiesis by stem cell factor alone in myelodysplastic syndrome patients with elevated endogenous erythropoietin serum levels

Anemia remains a therapeutic problem in patients with myelodysplastic syndrome (MDS). In view of the recently reported potential of stem cell factor (SCF) in restoring erythropoiesis in combination with erythropoietin (Epo), we first aimed to define a correlation between SCF serum levels and anemia in MDS. Endogenous SCF levels in 50 MDS patients were determined by using a quantitative sandwich enzyme immunoassay. Broad interindividual variations were observed, but SCF serum levels were in the normal range with no correlation to peripheral blood count. A soft agar culture system was used to further define the role of SCF for stimulation of erythroid growth. Bone marrow mononucleated cells of 20 MDS patients (4 refractory anemia, 5 refractory anemia with excess of blasts, 7 refractory anemia with excess of blasts in transition, and 4 chronic myelomonocytic leukemia) were investigated, and SCF plus Epo was able to stimulate burst-forming unit-erythroid significantly more than SCF or Epo alone independent of French-American-British group. When mononucleated cells from six MDS patients (two refractory anemia, two refractory anemia with excess of blasts, and 2 refractory anemia with excess of blasts in transition) with elevated serum Epo levels were incubated in the presence of SCF and autologous serum, a significant dose-dependent stimulation of burst-forming unit-erythroid number and cells per colony was detected. Erythroid differentiation was further enhanced by adding serum with high colony-stimulating activity obtained from patients with severe aplastic anemia. Our data suggest that in MDS patients with high endogenous Epo serum levels SCF alone might be effective in stimulating erythropoiesis in vivo.

Enzymatic production of hydroperoxides of unsaturated fatty acids by injury of mammalian cells

Hydroperoxides of unsaturated fatty acids (LOOHs) are generated by homogenisation of liver tissue, but not if the liver is boiled before homogenisation. This observation indicates that the LOOHs are produced in an enzymatic reaction. This assumption is corroborated by an analysis of the reduction products of LOOHs by gas chromatography/mass spectrometry (GC/MS). A main part of LOOHs is derived from linoleic acid and not from arachidonic acid. Massive cell damage occurs by myocardial infarction or other severe injuries; these events were found to be connected with generation of LOOHs. We suspect--considering the above outlined experiment--that the LOOH production is also mainly caused in these cases by activation of enzymes and not--as postulated--by an autocatalytic process. Increased amounts of LOOHs are found in many chronic diseases, e.g. in rheuma, atherosclerosis or psoriasis, obviously caused by a gradual damage of cells. Thus, the common root of an increased LOOH level might be cell injury.

Interaction of substance P with epidermal growth factor and fibroblast growth factor in cyclooxygenase-dependent proliferation of human skin fibroblasts

Substance P (SP), fibroblast growth factor (FGF), and epidermal growth factor (EGF) are mitogens for fibroblasts. EGF acts as a progression factor, whereas FGF and SP have competence factor activity. The ability of eicosanoids to regulate proliferation of fibroblasts and the increased production of prostaglandins by fibroblasts in response to the growth factors, led us to investigate the involvement of cyclooxygenase-dependent arachidonic acid metabolites in the mitogenic response of serum-starved human skin fibroblasts to SP, FGF, and EGF. We tested the interaction of a submaximal concentration of SP(10(-9)M) with baFGF(40 micrograms/ml) and EGF(0.01 microgram/ml) both on fibroblast proliferation and release of arachidonic acid metabolites. A combination of SP and EGF synergistically stimulated fibroblast proliferation and prostaglandin E2 release, whereas addition of SP to FGF-containing cultures did not affect cell growth. Inhibition of cyclooxygenase by acetylsalicylic acid augmented the growth response of fibroblasts to all: SP, FGF, and EGF. In the presence of acetylsalicylic acid, SP combined with FGF enhanced fibroblasts proliferation, whereas a combination with EGF inhibited cellular growth with respect to growth induced by EGF alone. Thus, interactions of SP with FGF and EGF differently affected the mitogenic response depending on the formation of arachidonic acid metabolites. The findings indicate that eicosanoids may be important mediators of competence and progression factor activities that may determine the effects of substance P on fibroblast proliferation in a cytokine network.

Serum neopterin, interleukin-4, and interleukin-6 concentrations in cerebral malaria patients and the effect of iron chelation therapy

To determine if iron chelation therapy alters immune responses in children with cerebral malaria, we retrospectively measured mean serum levels of neopterin, interleukin-4 (IL-4), and IL-6 in children who received desferrioxamine B or placebo for three days in addition to quinine-based therapy. Mean levels of neopterin, IL-4, and IL-6 were elevated above the expected normal range on admission. Neopterin correlated significantly with the degree of anemia, IL-4 with the duration of fever prior to admission, and IL-6 with parasite density. Serial measurements of cytokines and neopterin were performed over four days in 39 children, 21 randomized to receive desferrioxamine B and 18 to receive placebo. Mean concentrations of neopterin did not change significantly in either group while levels of IL-4 increased significantly in the placebo group (P = 0.04) but remained unchanged in the desferrioxamine B group. Interleukin-6 concentrations decreased markedly in both groups (P < 0.025). Stable IL-4 levels in children given desferrioxamine B may represent an inhibition of the T helper lymphocyte-2 (TH-2) response resulting from a strengthened TH-1 response associated with iron chelation therapy. Any effect of iron chelation on immunity in the setting of severe malaria will have to be confirmed in future prospective investigations.

Pulmonary sarcoidosis: patterns of cytokine release in vitro

This study was designed to investigate the ability of bronchoalveolar and blood mononuclear cells to produce inflammatory mediators in vitro in pulmonary sarcoidosis. Seventeen patients with pulmonary sarcoidosis (stage I n = 8; stage II/III n = 9) and 10 normal controls were investigated. Bronchoalveolar and peripheral blood mononuclear cells were cultured in serum-free medium, without stimulant, for 24 h, and the supernatants analysed for concentrations of interleukin (IL)-1 beta (IL-1 beta), IL-2, IL-6, tumour necrosis factor-alpha (TNF-alpha), granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon-gamma (IFN-gamma) and neopterin. Bronchoalveolar lavage cells (BALC) of sarcoid patients released significantly higher amounts of TNF-alpha, IL-6, IFN-gamma and neopterin in comparison to normal controls. When smokers were excluded, there was also an increased release of IL-1 beta and GM-CSF. In the sarcoid group, the levels of IL-1 beta, IL-6, TNF-alpha and GM-CSF showed highly significant correlations between each other, but not with IL-2, IFN-gamma or neopterin. Sarcoid patients whose BALC released more TNF-alpha or GM-CSF had higher percentage counts of alveolar macrophages but fewer lavage lymphocytes. In sarcoid patients, peripheral blood mononuclear cells (PBMNC) also released higher amounts of IL-1 beta, TNF-alpha, IL-6 and GM-CSF but less neopterin than normal controls. Patients whose PBMNC produced more IL-1 beta, IL-6 and GM-CSF had higher absolute and relative lavage neutrophil counts. No relationships were observed between cytokine release and radiographic or physiological markers of disease severity. We conclude from this study that sarcoid inflammation is associated with an increased and concerted release of monocyte/macrophage-derived cytokines not only in the lung but also in the peripheral blood. We speculate that the lymphokines, IFN-gamma and IL-2, are not the primary triggers.

[Immunostimulating protein 90K in ovarian carcinoma]

Protein 90K is a tumor-associated antigen, which is able to enhance the cytotoxic activity in lymphokine-activated and natural killer cells as well as the IL-2 release in peripheral blood lymphocytes. In our in vitro experiences we observed a stimulatory effect by IFN-alpha and IFN-gamma on 90K-specific mRNA expression and protein release in ovarian cancer cells, and 90K was furthermore found to be a potent stimulator of macrophage activity. Protein 90K seems to be involved in tumor immunology; it may represent a critical link between tumor and immune system.

Nitric oxide formation as predictive parameter for acute graft-versus-host disease after human allogeneic bone marrow transplantation

Due to the accumulation of evidence concerning a putative role of nitric oxide (NO) in graft-versus-host disease (GVHD), we performed follow-up measurements of the stable end-products of NO, nitrite/nitrate (NO2-/NO3-) in plasma of patients undergoing allogeneic (n = 16) and autologous (n = 6, as a control) bone marrow transplantation. NO2-/NO3- concentrations were set in relation to the clinical course and to serum levels of soluble tumor necrosis factor receptor 75 (sT-NFrec 75) and neopterin, both of which are known to be sensitive indicators of cellular immune activation phenomena involving macrophages in vivo, and endogenous interleukin (IL)-10, a major T helper cell type 2 (TH-2)-derived cytokine and potent inhibitor of macrophage activation and NO formation. A significant rise of NO2-/NO3- levels was observed in patients with GVHD and preceded the onset of clinical symptoms by up to 3 days. In contrast to indicators of macrophage activation, i.e., neopterin and sT-NFrec75, NO2-/NO3- concentrations were not significantly altered from baseline levels during infectious complications, as NO2-/NO3- concentrations did not fluctuate in patients after autologous engraftment. During episodes of acute GVHD, NO2-/NO3- concentrations showed a strong positive correlation with levels of plasma neopterin and sTNFrec 75, but were also significantly related to IL-10. In non-GVHD patients, a negative correlation between IL-10 and NO2-/NO3- concentrations was evident. Therefore, NO2-/NO3- determination may be a valuable early indicator of the initiation of human GVHD. Our results provide some further insights concerning cytokine-related metabolic changes in the course of human GVHD in vivo which may prove useful in the development of new therapeutic approaches for this disease.

Interleukin-1 receptor antagonist in differential diagnosis of inflammatory bowel diseases

BACKGROUND

Immunoregulatory properties of cytokines may mediate disordered inflammatory events in inflammatory bowel diseases (IBDs). On the basis of data obtained in experimental colitis, the hypothesis has been advanced that in IBD the balance between interleukin-1 (IL-1) and the naturally occurring IL-1 receptor antagonist (IL-1ra) might influence disease expression.

OBJECTIVE

We studied the profiles of IL-1ra and acute phase proteins produced by activated macrophages to determine whether the level of IL-1ra in peripheral blood is a marker of disease activity in IBD and a possible differential diagnostic marker.

PATIENTS AND METHODS

Levels of IL-1ra, serum neopterin, urinary neopterin, alpha 1-glycoprotein and C-reactive protein (CRP) were measured in 80 patients with ulcerative colitis, Crohn's disease or infectious colitis.

RESULTS

Levels of IL-1ra were markedly increased in patients with active ulcerative colitis or active Crohn's disease compared with those in patients with infectious colitis. Patients with active Crohn's disease had significantly higher serum IL-1ra levels than patients with active ulcerative colitis. Moreover, a positive correlation was found between levels of C-reactive protein, alpha 1-glycoprotein, and serum neopterin and the level of IL-1ra in active Crohn's disease but not in active ulcerative colitis, strongly suggesting that the pathogenesis of the two conditions differs.

CONCLUSION

Levels of IL-1ra in the peripheral blood of patients with IBD are of clinical relevance, representing a potent marker of disease activity and a possible differential diagnostic marker.

IL-6 secretion by human peritoneal mesothelial and ovarian cancer cells

Malignant ascites of epithelial ovarian cancer patients contains high levels of interleukin 6 (IL-6). The present study was conducted to compare the secretion of IL-6 by seven different human ovarian cancer cell lines (OVCA) and cultured human peritoneal mesothelial cells (HPMC) and to examine the regulation of its production by other cytokines. IL-6 was detected in supernatant medium of all mesothelial cell cultures (8/8) and 6/7 ovarian cancer cell lines. Levels of IL-6 secreted by HPMC (median 27,100 pg/1 x 10(5) cells; range 3870-168,200) were 590-fold higher (P < 0.01) than those secreted by OVCA (median 46 pg/1 x 10(5) cells; range 0-16,450). Treatment with TNF-alpha or IL-1 beta (both 10 ng/ml) for both types of cells and both cytokines resulted in a significant (P < 0.05) elevation of IL-6 production. In OVCA IL-6 secretion was increased 7- and 39-fold and in HPMC 6- and 8-fold, respectively. Under TNF-alpha treatment IL-6-levels secreted by HPMC were 149-fold higher (P < 0.01) than those generated by OVCA. Similarly, IL-1 beta-induced IL-6 levels were 102-fold higher in HPMC (median 288,800 pg/1 x 10(5) cells; range 93,125-552,800) than in OVCA. IFN-gamma (10 ng/ml) increased IL-6 generation in OVCA (6-fold) but not HPMC. The proliferation of both cell types however, was significantly (P < 0.05) inhibited by IFN-gamma. Our results suggest that peritoneal mesothelial cells may be a prominent source of IL-6 in ovarian cancer-related ascites.

Serum neopterin concentrations in chronic liver disease

Neopterin is produced by macrophages after stimulation with interferon gamma or lipopolysaccharide. Its production is increased in many infectious, autoimmune, and malignant diseases. The aim of this study was to examine whether, on the basis of neopterin as a marker, liver diseases could be classified according to aetiology and stage of disease. A cohort of 264 patients with chronic liver diseases (viral, metabolic, autoimmune, toxic) and 150 normal controls were studied; 136 of the patients had cirrhosis. Increased serum neopterin concentrations were found in 41% of all patients (controls 6.0 (2.2) nmol/l), with patients in the cirrhotic stage of disease showing higher neopterin values (mean (SD) 15.7 (23.6) nmol/ml) than those in the non-cirrhotic stage (9.9 (5.5)). There were no statistically significant differences in the serum neopterin concentrations that could be considered characteristic for different stages of disease classified according to the Child criteria. Such differences in concentrations of neopterin that were found in patients with liver diseases grouped according to underlying causes were only marginal. Serum neopterin concentrations were found to be significantly lower than in any other disease group only in patients with Wilson's disease. The results suggest that activated macrophages participate in the development of chronic liver disease. Measurement of serum neopterin does not offer a reliable method for differentiating between various aetiologies of chronic liver diseases and does not help to predict severity of cirrhosis.

Impaired nocturnal secretion of melatonin in coronary heart disease

Patients with coronary heart disease have increased nocturnal urinary noradrenaline. Because melatonin suppresses sympathetic activity, we measured serum melatonin concentrations at night (0200 h) in 15 patients with coronary heart disease. Melatonin was significantly lower in the patients than in 10 healthy controls (median 7.8 [interquartile range 6.5-11.8] vs 36.2 [32.2-42.5] pg/mL, p < 0.0001). Thus, impaired nocturnal secretion of melatonin is associated with coronary heart disease.

Growth-inhibitory effect of 2-CdA on myeloid CFU-GM progenitors in normal human long-term bone marrow cultures and its compensation by G-CSF or IL-3

As neutropenia is a common side effect of treatment with 2-chlorodeoxyadenosine (2-CdA), we investigated the myelosuppressive action of 2-CdA in Dexter-type human long-term bone marrow cultures (LTBMCs). LTBMCs were incubated with varying doses of 2-CdA (5 to 20 nM/L) during the first week. At 20 and 10 nM/L 2-CdA, we found a marked reduction in colony-forming unit-granulocyte/macrophage (CFU-GM) production throughout the culture period of 7 weeks (maximum reduction to 3.5% of untreated control cultures with 20 nM/L and to 27.2% with 10 nM/L, respectively). Even the lowest 2-CdA dose tested (5 nM/L) strongly reduced the number of CFU-GM progenitors during the first 3 weeks (maximum reduction to 52.4% of untreated controls), but this effect was transient, and values had recovered to normal within in 5 weeks. 2-CdA was also shown to cause a dose-dependent decrease in long-term culture-initiating cell (LTCIC) detections after 5 weeks in culture (49.6% of control cultures with 10 nM/L 2-CdA and 14% with 20 nM/L 2-CdA, respectively). When 2-CdA was added to LTBMCs initiated on preformed irradiated stromal feeder layers, similar results on CFU-GM production were obtained, indicating that the effects observed were not secondary to effects on the formation of a supportive layer. In addition, IL-6-concentrations in the supernatant of LTBMCs measured at various intervals after the addition of fresh medium with or without 2-CdA showed no significant decrease in cultures treated with 2-CdA. As neutropenia has been shown to be associated with a small but significant risk of fatal infection, we subsequently investigated the reversal potential of the 2-CdA effect by addition of recombinant human granulocyte colony-stimulating factor (rhG-CSF) or rh interleukin-3 (rhIL-3). The weekly addition of 100 ng/mL rhG-CSF counteracted the 2-CdA-mediated decrease in CFU-GM numbers during the entire period of 7 weeks, reaching statistical significance from weeks 3 to 7 (p < 0.05). Addition of rhIL-3 (100 ng/mL) showed an enhancement of CFU-GM output in 2-CdA-treated cultures that resulted in their numbers exceeding those in control cultures (without 2-CdA) from weeks 1 to 5 (p < 0.05) with a maximum increase of 5.1-fold over the parallel control value at week 3.(ABSTRACT TRUNCATED AT 400 WORDS)

[Captopril in the treatment of heart failure]

The inhibitor of angiotensin converting enzyme played in recent years a significant role in the treatment of cardiac failure. Captopril administration to patients after myocardial infarction prevents enlargement of the left ventricle and its dysfunction. This leads to a reduced mortality and fewer relapses of infarction even in patients with asymptomatic left ventricular dysfunction.

Electro-optic Pockels and Kerr effects for the determination of χ((2))and χ((3)): thin films of side-chain polymers containing dimethylaminonitrostilbene and of the polydiacetylene poly-(butoxycarbonylmethyleneurethane)

A simple reflection method that is based on ellipsometry and the electro-optic Pockels and Kerr effects is adapted for the determination of the electro-optic susceptibilities χ((2))(-ω; 0,ω) and χ((3))(-χ; 0, 0, ω). Measurements were made on materials that consist of centrosymmetric molecules like the polydiacetylene poly-(butoxycarbonylmethyleneurethane) (poly-4BCMU) and on a noncentrosymmetric poled sidechain polymer that contains dimethylaminonitrostilbene (ANS). The results are compared with those acquired by other methods (e.g., second-harmonic generation, third-harmonic generation, and degenerate four-wave mixing). Large differences occur, especially for the χ((3)) values. The effects of mechanical strains from electrostatic forces and from the field-dependent change of the absorption are discussed.

Serum concentrations of circulating endogenous granulocyte-macrophage colony-stimulating factor in HIV-1-seropositive injecting drug users

OBJECTIVES

We compared serum concentrations cytokines in seronegative and seropositive HIV-I intravenous drug abusers.

METHODS

The cytokines granulocyte-macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor alpha (TNF-alpha), interleukin-1 beta (IL-1 beta) and the immune activation markers soluble interleukin-2 receptor (sIL-2R) and neopterin were determined in sera of HIV-1-seropositive and HIV-1-seronegative injecting drug users (IDUs).

RESULTS

HIV-1-seropositive IDUs showed significantly lower serum concentrations of GM-CSF (p = 0.0064) and significantly higher concentrations of neopterin (p = 0.0005) than HIV-1-seronegative IDUs. All HIV-1-seropositive IDUs had neopterin levels above the normal range. Levels of TNF-alpha in HIV-1-seronegative IDUs did not differ from HIV-1-seropositive IDUs. Increased levels of IL-1 beta were found in 83.3% HIV-1-seronegative and in 94.4% HIV-1-seropositive IDUs with no significant difference between the two groups. An increase of serum levels of sIL-2R was found in 60% HIV-1-seronegative and in 63.6% HIV-1-seropositive IDUs. Again, no difference was found between the two groups. Neopterin concentrations correlated with TNF-alpha in HIV-1-seropositive as well as in HIV-1-seronegative IDUs, neopterin concentrations correlated with sIL-2R only in the HIV-1-seropositive IDUs. No correlations were found for GM-CSF.

CONCLUSIONS

An impaired production of GM-CSF may contribute to the loss of the myelopoetic progenitor cells and to the functional abnormalities of leukocytes associated with HIV-1 infection. Injecting drug use contributes to the levels of immune activation markers, therefore their use in HIV-1 infection may be limited in IDUs. However, neopterin remains a useful marker for HIV-1 infected IDUs.

Hepatocellular transplantation into the lung in chronic liver failure following bile duct obstruction in the rat

Injection of hepatocytes or cell-free supernatant into the lung was able to prevent death from surgically induced fulminant hepatic failure in the rat in over 90% and 53% of subjects, respectively. The aim of this study was to investigate whether this technique can be applied in chronic liver failure. Chronic liver failure was induced in Lewis rats by ligation and transection of the common bile duct, which led to cirrhosis after 3-5 wk in all animals. Four groups of animals were formed: group 1 (n = 5), normal rats, serving as control; group 2 (n = 15), cirrhotic rats, no further treatment; group 3 (n = 14), hepatocyte transplantation by injection of cell suspension transcutaneously into the right lung of cirrhotic animals four wk after bile duct ligation; group 4 (n = 17), injection of 1 mL cell-free supernatant intravenously at two-day intervals, starting 4 wk after ligation. Liver function tests, prothrombin time and serum protein levels were measured weekly before and every two days after transplantation. In group 2 all animals had died 56 (49-69) days after ligation. Survival in groups 3 and 4 was similar: all rats had died from liver failure 61 (51-72) and 60 (49-76) days following bile duct ligation. Survival rates and laboratory investigations showed no significant differences between treated and untreated cirrhotic animals. These data suggest that hepatocyte transplantation into the lung as well as supernatant injection do not have any significant effect on chronic hepatic failure, at least in the rat model.

Serum levels of interleukin 6, interleukin 8, and C-reactive protein after human allogeneic bone marrow transplantation

Serum levels of interleukin 6 (IL-6) and C-reactive protein (CRP) were measured every second day from day -6 to day +86 in 24 patients undergoing allogeneic (n = 23) and syngeneic (n = 1) bone marrow transplantation (BMT). Endogenous serum levels of IL-6, IL-8, and CRP were further analyzed during complications after BMT, such as fever of unknown origin (FUO), severe infectious complications and acute graft-versus-host disease (GVHD). In addition, CRP levels were measured in 10 patients with interstitial pneumonitis of various origins (CMV, idiopathic). In all 24 patients IL-6 and CRP levels showed a characteristic monophasic pattern. After a slight decrease in the first days after BMT, a significant increase was observed, starting on day +3/+5 (P < 0.05) and reaching peak levels on day +9/+11 (P < 0.01). CRP had a similar pattern, with an increase in serum levels on day +3/+5 and maximum levels one to three days after the IL-6 peak was reached. The magnitude of the peak was related to the development of complications in the further course of BMT and was high in patients with and low in patients without complications. Serum levels of both molecules returned to baseline after day 14 posttransplant. Increased IL-6 and CRP levels were observed in the further course of BMT during severe infections or FUO either on the day of clinical onset (IL-6) or three days later (CRP), but not during acute GVHD grade III/IV. CMV interstitial pneumonitis (CMV-IP) was accompanied by an increase in CRP levels, while no such elevations were observed in patients with idiopathic interstitial pneumonitis (IIP). Elevated IL-8 serum levels occurred during bacterial infections, but to a lesser amount also during GVHD and CMV-IP. In conclusion, a characteristic pattern of IL-6 and CRP was observed after allogeneic BMT and a further increase associated with infectious complications. Since no significant elevations were seen in patients with GVHD, we conclude that both molecules are not involved in the induction of GVHD and might be useful diagnostic tools for the prediction and diagnosis of infectious complications after BMT. In contrast, assessment of IL-8 serum values does not permit clinical complications to be specified.

Protective effects of various preservation solutions on cultured endothelial cells

Vascular endothelium represents the first target in organ preservation and plays an important role in reperfusion injury. Bovine aortic endothelial cells were cultivated and the most commonly used preservation solutions, such as University of Wisconsin HTK (Brettschneider's histidine-tryptophane-ketoglutarate), and Euro-Collins solutions were tested on the endothelial monolayer. In addition, one group of cultivated cells was preserved with cold saline solution, and endothelial monolayers grown in culture medium were used as controls. The quality of preservation was assessed after 24, 48, and 72 hours of cold storage. Reperfusion was simulated and its effects were observed by reincubation in culture medium at 37 degrees C for 6 hours. The total number of cells, cell viability (determined using trypan blue exclusion), and morphologic alterations were determined. Prostacyclin release was evaluated as a biochemical marker. University of Wisconsin solution maintains more than 99% cell viability after rewarming after both 24 and 48 hours of cold storage. After 72 hours, 86.7% of cells were still viable. Preservation with HTK and Euro-Collins solution allowed cell survival for only 24 hours (96.7%, HTK; 49.9%, Euro-Collins), with no viable cells seen after 48 hours. The cold saline-preserved sample showed 57.8% viable cells after 24 hours and 29.7% after 48 hours. No viable cells were detectable after 72 hours. Light microscopy revealed several patterns of both structural damage and intracellular change (nucleus and cytoplasm) in the endothelial monolayer after preservation with HTK, Euro-Collins solution, and cold saline solution. No morphologic alterations were seen in the University of Wisconsin solution group for as long as 72 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Lytic susceptibility of target cells to cytotoxic T cells is determined by their constitutive major histocompatibility complex class I antigen expression and cytokine-induced activation status

Cytotoxic T-cell lines (TCL) were raised in vitro using stimulator cells with a defined major histocompatibility complex (MHC) mismatch and tested in a cytotoxic chromium-release assay against haemopoietic and non-haemopoietic target cells from the original stimulator. Monoclonal antibody (mAb)-blocking experiments and simultaneous determination of MHC class I, class II, lymphocyte function-associated antigen-1 (LFA-1) and intracellular adhesion molecule-1 (ICAM-1) density by quantitative radioimmunometric methods and flow cytometry on target cells demonstrated that lysis was restricted by MHC class I and dependent upon the constitutive MHC class I antigen expression. Measurements showed a high constitutive expression of class I MHC antigens on peripheral blood mononuclear cells (PBMC), but a low one on keratinocytes (K). Also, PBMC were more susceptible to lysis by TCL than K. Interferon-gamma (IFN-gamma) treatment of K resulted in increased MHC class I antigen expression and enhanced lytic susceptibility to TCL. IFN-alpha and tumour necrosis factor-alpha (TNF-alpha) treatment, which did not modulate MHC class I antigen expression on K, did not influence the amount of K lysis either. None of the cytokines tested in this analysis, however, increased the expression of MHC class I, class II, ICAM-1 and LFA-1 on PBMC. Only IFN-gamma pretreatment showed a minimal, statistically significant increase in MHC class I antigen expression. In spite of the minimal effect of IFN-gamma and no effect of IFN-alpha on class I MHC expression, pretreatment of target cells with both cytokines considerably increased their lytic susceptibility. The mechanism of cytokine-induced enhanced lytic susceptibility to TCL was not explained by increased MHC class I, LFA-1 or ICAM-1 expression, since no correlation was found between surface expression of these molecules and lytic susceptibility to TCL. These data demonstrate that: (1) the constitutive density of MHC class I antigens determines the extent of TCL lysis; (2) IFN-gamma, and not IFN-alpha or TNF-alpha controls the amount of K target cell lysis by increasing their MHC class I antigen expression; and (3) IFN-gamma and IFN-alpha control the amount of PBMC target cell lysis by a mechanism independent of MHC class I, ICAM-1 or LFA-1 expression.

Genetically determined target organ susceptibility in the pathogenesis of spontaneous autoimmune thyroiditis: aberrant expression of MHC-class II antigens and the possible role of virus

Considerable controversy exists concerning the role of aberrant MHC-class II antigen expression in the pathogenesis of organ-specific auto-immune disease. Since Obese strain (OS) chickens are afflicted with a spontaneously occurring autoimmune thyroiditis (SAT), we have readdressed this pivotal question by investigating the chronical appearance of MHC-class II antigens on thyroid epithelial cells (TEC) of OS and normal healthy CB chickens before onset of overt clinical symptoms in the former. Among the candidates as potent inducers of aberrant MHC-class II antigen expression, interest in our studies focussed on the potential role of viruses in the development of SAT. Since aberrant MHC-class II antigen expression could prove to be an epiphenomenon of virally afflicted TEC, we determined 2,5-oligoadenylate synthetase and 2,5-oligoadenylatepolymer cytosol levels in both chicken lines. Our results indicate that the presence of infiltrating lymphocytes does not necessarily represent a prerequisite for the aberrant expression of MHC-class II antigens but coincides in most cases. However, the phenomenon seems to play a perpetuating rather than a causative role. Moreover, in support of a possible viral involvement, elevated levels of the 2,5-oligoadenylate synthetase and 2,5-oligomers could be demonstrated in TEC cytosol of OS chickens.

[Activated macrophages in the pathologic mechanism of pregnancy-induced hypertension]

Patients with hypertensive disorders of pregnancy demonstrated higher neopterin/creatinine ratios (urine) and elevated plasma levels of interleukin-6, tumor necrosis factor alpha and neopterin. A participation of macrophages in the pathomechanism of preeclampsia can thus be assumed.

Low-dose gamma-interferon therapy is ineffective in renal cell carcinoma patients with large tumour burden

The efficacy and immunomodulatory effects of low-dose gamma-interferon (gamma IFN) were investigated in an unselected population of patients with metastasising renal cell carcinoma. 36 patients suffering from metastasising renal cell carcinoma with a performance status exceeding Karnofsky index of 50 were entered into the open phase I/II trial. The majority of the patients recruited displayed a large tumour burden, and 28 patients (78%) had metastases involving two to six organ sites. Treatment was started with a 2-week cycle of either daily or weekly subcutaneous administration of either 100, 200 or 400 micrograms gamma IFN. After a therapy-free interval of 2 weeks treatment was switched to the alternate mode of administration. Subsequently, treatment was continued with the same dose applied once a week for a minimum of 3 months. Serum levels of neopterin and beta-2-microglobulin, as well as flow cytometric analyses of peripheral blood mononuclear cells, were used for the assessment of biological response. Minimal antitumour activity was observed in this high-risk patient group and only 1 patient experienced a partial response (PR) lasting 36 + months. Comparison of the patients' characteristics to those of other low-dose gamma IFN trials revealed a highly significant difference in the tumour burden and clinical response. We conclude that patient selection is a decisive parameter for the outcome of treatment with low-dose gamma IFN, and that patients with poor prognostic features and a large tumour burden are not likely to respond to this almost atoxic treatment.

Sodium-taurocholate-induced acute necrotizing pancreatitis does not affect jejunal oxygenation in pigs

OBJECTIVE

To study the influence of experimentally induced acute necrotizing pancreatitis on jejunal oxygen transport, jejunal oxygen consumption, and mucosal PO2.

DESIGN

Prospective, randomized trial.

SETTING

Animal laboratory.

SUBJECTS

Domestic pigs aged 7 to 8 wks.

INTERVENTIONS

Two groups of pigs were anesthetized with midazolam and sufentanyl, mechanically ventilated, and hemodynamically monitored. In controls (n = 9) and in animals with acute necrotizing pancreatitis (n = 9), a segment of the jejunum was isolated and autoperfused in situ. Through an antimesenteric enterotomy, an area of jejunal mucosa was exposed for mucosal PO2 measurements. Acute necrotizing pancreatitis was induced by the injection of 10 mL of 10% sodium-taurocholate into the main pancreatic duct. Both groups received normal saline solution to keep pulmonary artery occlusion pressure constant.

MEASUREMENTS

Mucosal PO2 was assessed with a modified Clark-type multiwire surface electrode. After two baseline measurements, systemic and regional oxygen transport variables and mucosal PO2 were determined at designated intervals (20, 40, 60, 100, 120, 160, 200, 240, 280 mins).

MAIN RESULTS

Systemic hemodynamics and oxygen transport were maintained in both groups. In contrast to controls, all animals with pancreatitis showed gross macroscopic and histologic evidence of severe acute necrotizing pancreatitis at autopsy. There were no significant differences between groups in jejunal blood flow, oxygen transport, oxygen consumption, oxygen extraction ratio, or mucosal PO2.

CONCLUSIONS

Our results demonstrate that, under conditions of sustained systemic hemodynamics, jejunal oxygen transport and mucosal oxygenation are well maintained during the early course of sodium-taurocholate-induced acute necrotizing pancreatitis.

Interleukin-6 in multiple myeloma: correlation with disease activity and Ki-67 proliferation index

Interleukin-6 (IL-6) is supposed to be a growth factor in multiple myeloma (MM). Applying a bioassay and a modified ELISA, we measured serum IL-6 values in 64 patients with overt MM, seven patients with smouldering myeloma (SMM), 57 patients with monoclonal gammopathy of undetermined significance (MGUS) and 40 healthy volunteers as controls. IL-6 failed to discriminate between MGUS and MM, stage I, whereas comparison of MM, stage I and stage II/III (p = 0.0143), or comparison of stable disease/remission and progressive disease (p < 0.0001) revealed significant differences. Furthermore, we found significantly higher IL-6 values in overt MM compared to SMM (p = 0.0018). Using a Ki67/CD38 immunohistological double staining method we found a significant correlation between proliferation of bone marrow myeloma cells and serum IL-6 values in 15 patients (p = 0.005). These data demonstrate that IL-6 is a parameter of disease activity in MM and, beside its role in tumor biology, may become a valuable supplement to the established risk factors when selecting patients with unfavourable clinical course for more aggressive treatment modalities.

Effects of cytokine application on glucocorticoid secretion in an animal model for systemic scleroderma

We previously reported on an altered immune-endocrine feedback loop via the hypothalamo-pituitary-adrenal (HPA) axis in Obese strain (OS) chickens afflicted with spontaneous autoimmune thyroiditis. These animals are deficient in plasma corticosterone increase after antigenic challenge or application of cytokine-containing conditioned medium of mitogen-stimulated spleen cells (CM). To investigate whether the impaired ability to respond to cytokines with glucocorticoid-increasing factor (GIF) activity, e.g. interleukin 1 (IL 1), is restricted to OS chickens as a model for an organ-specific autoimmune disease, we extended our experiments to another autoimmune-prone animal strain, the chickens of the University of California at Davis line 200 (UCD-200). These animals develop an inherited inflammatory fibrotic disease that closely resembles human progressive systemic sclerosis (scleroderma). Application of GIF-containing CM to UCD-200 chickens leads to a transient increase in glucocorticoid serum levels within 1-2 hours comparable to that of controls. But, while corticosterone levels in the latter returned to normal baseline levels after 4 hours, they were still elevated in autoimmune chickens. Although the peak of the glucocorticoid hormone serum concentrations was equal to that of controls, UCD-200 had to secrete twice as much adrenocorticotropic hormone to achieve this corticosterone serum level due to an apparent hyporesponsiveness of the adrenal gland to this secretagogue. The altered cytokine-induced glucocorticoid secretion is found in early as well as in chronic, sclerotic stages of the disease. Cellular alterations in the peripheral blood of UCD-200 chickens during the prolonged elevated corticosterone section, i.e. between 2-4 hours after CM application, are characterized by a significant decrease in the percentage of CD4+ and CD8+ cells. Furthermore, a significant increase in B cells up to 24 hours with a maximum after 1 hour was found. The proliferative response to the mitogen concanavalin A of peripheral mononuclear cells was inversely correlated to the serum corticosterone level, showing a permanent decrease of 80-90% after 1-4 hours in autoimmune animals. This functional alteration in UCD-200 was accompanied by an 80% decrease in serum interleukin 2 (sIL 2) activity 4 hours after CM application. Twenty-four hours later an eight-fold increase in sIL 2 rebound activity was found, indicating that the inhibitory effect of corticosterone in UCD-200 chickens is not long-lasting.

Increased levels of serum neopterin and decreased production of neutrophil superoxide anions in chronic heart failure with elevated levels of tumor necrosis factor-alpha

OBJECTIVES

The purpose of this study was to examine the role of tumor necrosis factor-alpha and tetrahydrobiopterin and superoxide anion release from neutrophils in severe chronic heart failure.

BACKGROUND

Previous studies have demonstrated elevated production of tumor necrosis factor-alpha and free radical-induced endothelial cell damage in severe heart failure.

METHODS

Plasma and serum levels of immunoreactive interleukin-1, interleukin-6, interferon-gamma, neopterin and tumor necrosis factor-alpha and the release of superoxide anions from circulating neutrophils both at basal conditions and after triggering with f-Met-Leu-Phe or phorbol 12-myristate 13-acetate were measured in 16 patients with severe heart failure and in 11 healthy control subjects.

RESULTS

Circulating levels of tumor necrosis factor-alpha and neopterin were elevated in patients with heart failure compared with values in control subjects. A significant correlation between the two was found. Basal and phorbolester-triggered release of oxygen radicals from neutrophils was not affected in patients with heart failure. However, formylpeptide-stimulated release of oxygen radicals by neutrophils was significantly reduced.

CONCLUSIONS

Suppressed neutrophil function in patients with heart failure exhibiting elevated levels of tumor necrosis-alpha factor may indicate self-protection against the deleterious effects of neutrophil-derived oxygen radicals. Through induction of tetrahydrobiopterin synthesis (as reflected by increased neopterin), tumor necrosis factor-alpha may affect nitric oxide synthesis.