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)

Prevalence of hepatocellular carcinoma in alpha-1-antitrypsin deficiency.

The aim of the present study was to determine the prevalence of hepatocellular carcinoma in adults with heterozygous alpha 1-antitrypsin deficiency and to assess the presence of possible co-risk factors for the development of hepatocellular carcinoma. Two hundred and forty patients with cirrhosis of different aetiologies and 130 patients with alpha 1-antitrypsin deficiency without evidence of chronic liver disease were investigated. Out of the 240 patients with cirrhosis, 61 patients (25%) were found to have alpha 1-antitrypsin deficiency, 36 patients (15%) had chronic hepatitis C infection, 50 (21%) had chronic hepatitis B and 24 (10%) had hepatitis C and hepatitis B infection. Thirty patients (12%) had cryptogenic cirrhosis and 39 (16%) alcoholic cirrhosis. The prevalence of hepatocellular carcinoma in patients with alpha 1-antitrypsin deficiency-associated cirrhosis was comparable to that of hepatocellular carcinoma in patients with cirrhosis of other aetiologies. Positive viral markers were found in 67% of the patients with alpha 1-antitrypsin deficiency-associated cirrhosis with hepatocellular carcinoma. In contrast, in the group of 130 patients with alpha 1-antitrypsin deficiency but without clinical and laboratory signs of chronic liver disease, none was found to have hepatocellular carcinoma (p = 0.001). Our results indicate that heterozygous alpha 1-antitrypsin deficiency-associated cirrhosis is a risk factor for hepatocellular carcinoma, but this is due to chronic liver disease and not due to the metabolic disorder itself.

Alpha-1-antitrypsin deficiency and liver disease.

Alpha-1-antitrypsin deficiency is a common autosomal recessive disorder associated with premature development of emphysema, liver cirrhosis and hepatocellular carcinoma. This article reviews the existing literature on alpha-1-antitrypsin deficiency, with an emphasis on recent developments. A description of the protein, gene structure and function of alpha-1-antitrypsin as well as clinical aspects are presented. Treatment issues are addressed and a framework for the diagnostic workup and management of patients with alpha-1-antitrypsin deficiency and chronic liver disease is provided.

The acute-phase protein alpha 1-antitrypsin inhibits growth and proliferation of human early erythroid progenitor cells (burst-forming units-erythroid) and of human erythroleukemic cells (K562) in vitro by interfering with transferrin iron uptake.

We have previously shown that the hepatic acute-phase protein alpha 1-antitrypsin (alpha 1-AT) inhibits transferrin (tf) binding to its receptor (tfR) of human placental membranes. To evaluate the possibility that this interaction can explain the pathophysiology of the changes in iron metabolism in the course of chronic disease, subsequently leading to anemia in chronic disease (ACD), we examined the effect of alpha 1-AT on cells of the erythroid cell line. alpha 1-AT completely prevented tf binding to tfR on K562 human erythroleukemic cells and on reticulocytes. This inhibitory potency was dose-dependent and competitive, as proved in equilibrium saturation and kinetic studies. The cytokines interleukin-1 (IL-1), IL-6, and tumor necrosis factor alpha showed no such effect. Internalization of the tf-tfR complex was inhibited with alpha 1-AT in a dose-dependent manner. Furthermore, alpha 1-AT profoundly reduced the growth of K562 cells as well as their proliferation, albeit to a lesser degree. Growth of early erythroid progenitor cells (burst-forming units-erythroid) was significantly suppressed by alpha 1-AT, but no effect on the growth of late erythroid progenitor cells (colony-forming units-erythroid) was detected. These inhibitions of alpha 1-AT were seen in high physiologic concentrations attained in the course of acute-phase situations. These data show that alpha 1-AT might be a mediator of the changes in iron metabolism that are characteristic of clinical findings in the course of ACD.

[Prognosis and life expectancy in primary biliary cirrhosis]. / Prognose und Lebenserwartung bei Primär biliärer Zirrhose.

The aim of the present study was to investigate prognosis and life expectancy in patients with primary biliary cirrhosis. We retrospectively analysed 59 patients from western Austria over 15 years (mean 6 years). The results of the present study were compared with the average life expectancy of the population of western Austria and with the results of the Mayo study published in 1989. The mean survival time in our study was 112.7 months, 25% were dead by 132 months. Kaplan-Meier analysis showed a 95% probability to survive 1 year and a 84% probability to be alive at 5 years. Asymptomatic patients had a significantly better prognosis than symptomatic patients. In comparison with the Mayo study the patients in our study had a better prognosis and in comparison with the normal population a significantly worse life expectancy.

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.

Inhibition of superoxide anion release from circulating neutrophils by L-arginine in man.

In animal studies of myocardial ischemia/reperfusion L-arginine reduces necrotic injury by preservation of endothelial function and attenuation of neutrophil accumulation in ischemic cardiac tissue. Because release of oxygen radical species by circulating neutrophils is important in endothelial function and ischemia-reperfusion injury, this study investigated the effect of intravenous administration of L-arginine on the in vitro release of superoxide anion of neutrophils in healthy young adults. Neutrophils were obtained at various time points before, during, and after infusion of L-arginine (17 mg kg-1 min-1 for 30 min) and analyzed for superoxide dismutase inhibitable reduction of ferricytochrome c. The spontaneously occurring respiratory burst of polymorphonuclear leukocytes at basal conditions was compared with that after triggering by 1 mumol/l formylpeptide or 50 ng/ml phorbolester. Infusion of L-arginine inhibited both basal (P < 0.01) and formylpeptide-triggered (P < 0.05) release of superoxide anion did, but not affect release stimulated by phorbol 12-myristate 13-acetate. Pretreatment of neutrophils with 1 mmol/l L-arginine in vitro also significantly reduced formylpeptide-triggered (1 mumol/l) superoxide anion release, suggesting that the affects observed after in vivo pretreatment may be due to direct action of L-arginine on neutrophils. These findings demonstrate the ability of L-arginine to reduce release of oxygen radical species by circulating neutrophils in man.

Spontaneous bacterial peritonitis is associated with high levels of interleukin-6 and its secondary mediators in ascitic fluid.

We investigated 37 patients with ascites and liver cirrhosis in order to examine whether on the basis of correlation of cytokines and acute phase proteins of the ascitic fluid, prognosis of spontaneous bacterial peritonitis can be made. Significantly enhanced levels of interleukin-6, as well as acute phase reactants alpha-1-antitrypsin and C-reactive protein were found in the ascitic fluid of patients with spontaneous bacterial peritonitis. The levels of tumour necrosis factor alpha (TNF-alpha), neopterin, interleukin 2-receptor and granulocyte-macrophage colony stimulating factor were higher in patients with spontaneous bacterial peritonitis, but without statistical significance, whereas no differences were found between the interferon gamma, interleukin-2 and interleukin-1 levels. In addition, interleukin-6, TNF-alpha and neopterin levels were found to correlate significantly with the outcome of the disease. These findings show that acute phase reaction occurs in the ascitic compartment in correlation with the development of spontaneous bacterial peritonitis.

Stimulation of monocyte chemotaxis by human growth hormone and its deactivation by somatostatin.

Monocyte infiltration occurs early in the course of inflammation and is a prerequisite for optimal repair of tissue damage. In this study, human recombinant growth hormone was shown to be a potent chemoattractant for human monocytes, inducing migration at picomolar concentrations of recombinant human growth hormone. Chemotaxis of monocytes was measured in vitro by a modified Boyden chamber assay using nitrocellulose micropore filters and measuring microscopically the migration depth of the leading front of monocytes. Somatostatin, which inhibits the release of growth hormone, and its long-acting analogue, octreotide, also stimulated chemotaxis of monocytes; however, the effective peptide concentration was in the micromolar range. When tested for chemotaxis in combination or in experiments using pretreatment with somatostatin and washing of treated cells, somatostatin significantly antagonized the chemotactic responses of monocytes to growth hormone. The inhibitory effect on growth hormone-stimulated chemotaxis was dose dependent and occurred at concentrations severalfold lower than the chemotactically active concentration of somatostatin. Combinations of growth hormone with interferon or substance P also deactivated the chemotactic responses. These observations suggest that human growth hormone may have a regulatory role in monocyte chemotaxis.

High-affinity substance P binding sites of neurokinin-1 receptor type autoradiographically associated with vascular sinuses and high endothelial venules of human lymphoid tissues.

BACKGROUND: Factors that affect leukocyte-endothelial cell interaction in high endothelial postcapillary venules and vascular sinuses of lymphatic tissues indirectly regulate immune function. Studies in sheep demonstrated that acute infusion of substance P (SP) into cannulated popliteal lymph node afferent lymphathics produced a marked and prolonged increase in the output of lymphocytes into nodal efferent lymph. The proposed mechanism is an influence of SP on lymph vascular systems. Such functional importance of the immunoregulatory properties of SP in man is unknown. EXPERIMENTAL DESIGN: The expression and distribution of SP receptors in human lymphoid tissue was investigated using slide-mounted fresh-frozen sections of lymph node, hyperplastic tonsillitis, and spleen for ligand binding and autoradiographic studies. RESULTS: Specific binding of radiolabeled SP to lymph node and tonsils reached a plateau within approximately 40 minutes, being half-maximal at 20 minutes. The specific binding was between 65 and 75% of total binding. In contrast, iodinated neurokinin A under identical incubation conditions, did not significantly associate with the tissues. Neither the SP nor the neurokinin A tracer specifically associated with spleen. Binding specificity of radiolabeled SP was analyzed in binding competition experiments. Synthetic SP, SP (3-11), a selective neurokinin-1 agonist and a neurokinin-1 antagonist competed with the specific binding of SP to lymph node and tonsil sections. The half-maximal inhibition of binding was obtained at a concentration of about 0.5 nmol/liter of SP. The fragment SP (1-4) and selective neurokinin-2 ligands did not compete with the specific binding of SP. Scatchard and nonlinear algorithm analyses revealed two binding sites for SP. For lymph node and tonsil, one site showed a high affinity of about 0.4 nmol/liter and 0.7 nmol/liter and a low capacity for SP, respectively. The second site exhibited a lower affinity of 100 nmol/liter and 50 nmol/liter and a higher capacity for SP in lymph node and tonsil, respectively. Autoradiographic localization of the binding sites shows a very high concentration of silver grains when compared with controls. The reaction occurred mainly over vascular sinuses and high endothelial venules with heterogenous density. Silver grain accumulation was also noticed over the marginal sinuses of the B cell follicles. CONCLUSIONS: The biochemical results indicate the presence of neurokinin-1 receptors in human lymph node and tonsil. We suggest that the neurokinin-1 receptors localized to vascular tissues of lymph node and tonsil mediate the affects of SP on lymphocyte traffic, and we propose that SP plays a regulatory role in lymphocyte homing in man.

Inhibition of recombinant human growth hormone-induced and prolactin-induced activation of neutrophils by octreotide.

Growth hormone, prolactin and somatostatin are polypeptide hormones of the neuroendocrine and peripheral nervous systems. In vitro, these have opposing effects on cells of the immune system. We compared the effects of these peptides on activation of neutrophils using a recombinant preparation of human growth hormone, human prolactin and octreotide, a long acting analog of somatostatin. In the absence of growth hormone, octreotide did not affect either neutrophil locomotion or respiratory burst. Octreotide, however, significantly antagonized growth hormone-induced activation of neutrophils for enhanced respiratory burst as well as growth hormone-induced inhibition of stimulated migration. As the effect of growth hormone on neutrophils is mediated by the prolactin receptor, its inhibition by octreotide was also tested using prolactin as priming agent. Data indicate comparable effects of octreotide on priming of neutrophils by prolactin. The effect of octreotide was dose-dependent and appeared to be selective, as activation of neutrophil respiration burst by gamma-interferon, and inhibition of stimulated migration by tumor necrosis factor-alpha were unaffected by octreotide. The present study suggests that octreotide may act on neutrophils directly by antagonizing growth hormone or prolactin at the cellular level.

The hepatic acute-phase proteins alpha 1-antitrypsin and alpha 2-macroglobulin inhibit binding of transferrin to its receptor.

Transferrin binding to human placental sites was inhibited by the acute-phase proteins alpha 1-antitrypsin (alpha 1-AT) and alpha 2-macroglobulin (alpha 2-MG), whereas haptoglobin, C-reactive protein and ferritin displayed no such effect. In equilibrium saturation binding assays, the effective acute-phase proteins decreased the apparent affinity of the binding sites for transferrin, but the transferrin binding-site density Bmax. was not significantly changed. For instance, the addition of 30 microM alpha 1-AT increased the KD of transferrin from 8.46 +/- 1.51 nM to 21.6 +/- 3.04 nM; the Bmax. values were 1.17 +/- 0.18 pmol/mg of protein and 1.04 +/- 0.25 pmol/mg of protein respectively. In kinetic studies, alpha 1-AT decreased the association rate constant k+1 of the 125I-transferrin-binding-site complex from 2.18(+/- 0.21) x 10(7) M-1.min-1 to 3.99(+/- 0.18) x 10(6) M-1.min-1. In contrast, the dissociation rate constant k-1 was not changed (0.0948 +/- 0.002 min-1, 0.089 +/- 0.0017 min-1). On isoelectric focusing, no alteration in transferrin protein pattern or shift in isoelectric point was detected in the presence of alpha 1-AT. Inhibition of transferrin binding by the acute-phase proteins alpha 1-AT and alpha 2-MG is competitive. Interestingly, inhibition is already present at physiological concentrations. However, full inhibition is only achieved at concentrations above the normal range, which are attained in acute-phase reactions.

[After-care by the internal medicine physician following liver transplantation]. / Internistische Nachsorge nach Lebertransplantation.

Orthotopic liver transplantation offers the only therapeutic option for many patients with end-stage liver disease. In adults, the overall five-year survival following transplantation has increased dramatically from approximately 30% a decade ago to nearly 70% currently. Cyclosporine A became available in the 1970s and substantially improved immunosuppressive therapy. It is now the mainstay of the therapeutic approach to prevent graft rejection. The postoperative care of liver transplant recipients is one of the most exciting challenges in clinical medicine. On the basis of the experience and results of the Innsbruck liver transplant programme the management of liver transplant recipients will be discussed with regard to the typical time frame of complications. We present data of 87 liver transplantations in 84 patients during a 10-year observation period. At present, intraoperative mortality is fortunately close to zero. Most of the deaths occur in the immediate postoperative period. Major complications are haemorrhage, hepatic artery or portal vein thrombosis, biliary leakage or graft dysfunction. In addition, side-effects resulting from high-dose immunosuppressive therapy or from antibiotic and antiviral therapy add to problems in this early period. Opportunistic infections, chronic graft failure, disease recurrence and nephrotoxicity related to Cyclosporine A therapy are complications seen during long-term management of liver transplant patients. The differential diagnosis and the adequate management of these complications are a great challenge to every hepatologist.

Regulation of myeloid phagocyte development and function by growth hormone: a review.

Growth hormone (GH) has previously been implicated in T cell development and function, and here we review its efficacy in promoting development and function of myeloid cells. Evidence obtained from both in vitro and in vivo studies suggests that, in animals as well as in man, GH augments proliferation and differentiation of erythroid, megakaryocytic and myeloid progenitor cells. Mechanisms of hemopoietic actions probably involve induction of insulin-like growth factor-1, which is under GH control. Effects are mostly, though not exclusively, seen in GH deficiency states. Like other hemopoietic factors currently undergoing clinical trials for modulation of mature phagocyte function, GH is found in vitro and in vivo to stimulate potently monocyte migration and to prime neutrophils and macrophages for enhanced activation by second stimuli. Activation of neutrophils is mediated by GH action on the neutrophil prolactin receptors. The detailed mechanism of macrophage activation is currently unknown. GH action on myeloid phagocytes may help to explain protective effects of GH observed in experimental infection as well as its promotive effect on wound healing.

[Trans-septo-sphenoidal operation for pituitary adenoma in 92 patients: results and follow-up endocrine studies]. / Transseptosphenoidale Operation von Hypophysenadenomen bei 92 Patienten: Ergebnisse und endokrine Verlaufskontrolle.

The short- and long-term therapeutic results of transseptosphenoidal adenomectomy were studied retrospectively in 92 patients with pituitary tumors (42 nonsecreting adenomas, 21 GH-, 15 PRL-, 10 ACTH-, 2 TSH-, and 2 FSH-secreting adenomas). Severe surgically related complications were not observed. The early remission rate was 53.7% in nonsecreting, 57.1% in GH-secreting, 60% in PRL-secreting, 88.9% in ACTH-secreting, and 75% in TSH- or FSH-secreting adenomas. The recurrence rate in patients with nonsecreting adenomas was 47.1%, with GH-secreting adenomas 10%, with ACTH-secreting adenomas 25%, and with TSH- or FSH-secreting adenomas 66.7%, respectively. A long-term cure rate of 69.2% was observed in prolactinomas in combination with a facultative dopamine agonist therapy. More patients had normal pituitary function concerning TSH, ACTH, and LH/FSH post-operatively (48.9% versus 46.6% preoperatively). These data confirm that transseptosphenoidal surgery is a safe and selective treatment for pituitary adenomas with efficient preservation of the normal pituitary gland.