Granulocyte colony-stimulating factor (CSF) but not interleukin-1 (IL- 1), IL-3, and granulocyte-macrophage CSF protect bone marrow progenitor cells from suppression by allosensitized cytotoxic T cells

The major immunological reactions after an allogeneic bone marrow transplantation (BMT) are graft rejection and graft-versus-host disease (GVHD). GVHD can be prevented by T-cell depletion of the allogeneic BM graft, but the beneficial effect of T-cell depletion on the incidence of GVHD is counterbalanced by a higher incidence of graft failure. One option for the prevention of graft rejection after T-cell-depleted BM grafts is the administration of cytokines. Before applying cytokines after an allogeneic BMT, we considered it desirable to learn whether cytokines would alter the susceptibility of donor BM cells to host T cells. An in vitro assay was developed to investigate the role of the cytokines interleukin-1 (IL-1), IL-3, granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage CSF (GM-CSF) on the interaction between allosensitized, cytotoxic-T cells (CTLs) and T-cell- depleted BM cells. CTLs primed against the BM donor suppressed the formation of colonies consisting of granulocytes and macrophages (colony-forming unit GM). Colony formation was not inhibited by CTLs sensitized against a third party. Accordingly, the number of colonies scored in cocultures with CTLs sensitized to third party antigens were designated as 0% inhibition. A 66% inhibition of colony formation was observed for untreated BM cells at an effector:target (E:T) ratio of 1:1. Pretreatment of the BM cells with the cytokines G-CSF, GM-CSF, IL- 1, and IL-3 resulted in a 38% (P = .001), 53%, 66%, and 68% inhibition of colony formation, respectively, at E:T ratios of 1:1. G-CSF reduced the susceptibility of BM cells over a range from 4:1 to 1:16 (E:T ratios). GM-CSF had only significant influence at the lower E:T ratios (1:4 and 1:16). These in vitro data indicate that G-CSF could protect BM cells from killing by allosensitized CTLs and suggest that administration of these cytokines might potentially reduce the susceptibility of T-cell-depleted allogeneic BM grafts to host T-cell- mediated rejection.     

Tumor necrosis factor alpha receptor 1 deficiency in hepatocytes does not protect from non-alcoholic steatohepatitis,but attenuates insulin resistance in mice

BACKGROUND End-stage liver disease caused by non-alcoholic steatohepatitis(NASH) is the second leading indication for liver transplantation. To date, only moderately effective pharmacotherapies exist to treat NASH. Understanding the pathogenesis of NASH is therefore crucial for the development of new therapies. The inflammatory cytokine tumor necrosis factor alpha(TNF-α) is important for the progression of liver disease. TNF signaling via TNF receptor 1(TNFR1) has been hypothesized to be important for the development of NASH and hepatocellular carcinoma in whole-body knockout animal models.AIM To investigate the role of TNFR1 signaling in hepatocytes for steatohepatitis development in a mouse model of diet-induced NASH.METHODS NASH was induced by a western-style fast-food diet in mice deficient for TNFR1 in hepatocytes(TNFR1~(ΔHEP)) and their wild-type littermates(TNFR1~(fl/fl)). Glucose tolerance was assessed after 18 wk and insulin resistance after 19 wk of feeding. After 20 wk mice were assessed for features of NASH and the metabolic syndrome such as liver weight, liver steatosis, liver fibrosis and markers of liver inflammation.RESULTS Obesity, liver injury, inflammation, steatosis and fibrosis was not different between TNFR1~(ΔHEP) and TNFR1~(fl/fl) mice. However, Tnfr1 deficiency in hepatocytes protected against glucose intolerance and insulin resistance.CONCLUSION Our results indicate that deficiency of TNFR1 signaling in hepatocytes does not protect from diet-induced NASH. However, improved insulin resistance in this model strengthens the role of the liver in glucose homeostasis.     

Diffuse esophageal spasm: not diffuse but distal esophageal spasm (DES)

Diffuse esophageal spasm is an uncommon motility disorder that is found in less than 5% of patients undergoing esophageal motility testing for dysphagia. It is defined manometrically by the presence of 20% or more simultaneous contractions in the distal esophageal body with normal peristalsis. This motility abnormality has been traditionally identified as occurring primarily in the smooth muscle portion of the distal esophagus yet, the term diffuse persists in the medical literature to identify DES. The aim of our study was to assess the diffuse or limited nature of this entity by evaluating the prevalence of simultaneous contractions in both proximal and distal esophagus in patients with DES. We reviewed esophageal motility tracings of 53 consecutive patients (32 F, 21 M) with DES and compared them with 53 age-matched patients with manometric normal studies. In the distal esophagus we found 195 simultaneous contractions (37% of swallows) with a median of 3 and range of 2–7 per patient. Of the 53 patients with DES a total of 13 simultaneous contractions (2% of swallows) occurred in the proximal esophagus with only 3 (5.6%) of the 53 patients having 2 or more simultaneous contractions in 10 swallows. None of the patients with normal manometry showed more than one simultaneous contraction in either proximal or distal esophagus. In conclusion, these findings suggest that the term diffuse esophageal spasm is a misnomer and the DES is more appropriately described as distal esophageal spasm.     

Stress-induced behaviors require the corticotropin-releasing hormone (CRH) receptor, but not CRH

Corticotropin-releasing hormone (CRH) is a central regulator of the hormonal stress response, causing stimulation of corticotropin and glucocorticoid secretion. CRH is also widely believed to mediate stress-induced behaviors, implying a broader, integrative role for the hormone in the psychological stress response. Mice lacking the CRH gene exhibit normal stress-induced behavior that is specifically blocked by a CRH type 1 receptor antagonist. The other known mammalian ligand for CRH receptors is urocortin. Normal and CRH-deficient mice have an identical distribution of urocortin mRNA, which is confined to the region of the Edinger-Westphal nucleus, and is absent from regions known to mediate stress-related behaviors. Since the Edinger-Westphal nucleus is not known to project to any brain regions believed to play a role in anxiety-like behavior, an entirely different pathway must be postulated for urocortin in the Edinger-Westphal nucleus to mediate these behaviors in CRH-deficient mice. Alternatively, an unidentified CRH-like molecule other than CRH or urocortin, acting through the CRH receptors in brain regions believed to mediate stress-induced behaviors, may mediate the behavioral response to stress, either alone or in concert with CRH.     

Alcohol-extracted, but not intact, dietary soy protein lowers lipoprotein(a) markedly

We previously found that dietary soy protein produces higher lipoprotein(a) [Lp(a)] plasma concentrations than does casein. This study tested the hypothesis that soy protein contains Lp(a)-raising alcohol-removable components. Twelve normolipidemic women and men consumed, in a crossover design, liquid-formula diets containing casein, soy protein, or alcohol-extracted soy protein. Dietary periods of 32 days were separated by washout periods on self-selected diets. Fasting lipid and Lp(a) levels were measured throughout. Median Lp(a) concentration was >2-fold greater after 28 to 32 days on a soy protein diet than after an extracted soy protein diet (P<0.001). Lp(a) concentrations after casein and extracted soy protein diets were virtually identical. Women and men responded similarly. When the switch was made from a self-selected to a soy protein diet, median Lp(a) concentration increased 16% after 1 week (P<0.01) and subsequently decreased toward baseline; extracted soy protein and casein diets never exhibited increased median Lp(a) levels, and after 28 to 32 days, these levels were decreased >60% below baseline (P<0.001 and P<0.01, respectively). Low density lipoprotein cholesterol concentrations were not different after the 3 experimental diets. The data indicate that (1) dietary soy protein can increase Lp(a) concentrations, (2) this effect is eliminated after alcohol extraction, and (3) high Lp(a) concentrations may be markedly reduced by diet.     

Caloric restriction lowers plasma lipoprotein (a) in male but not female rhesus monkeys

Many age-associated pathophysiological changes are retarded by caloric restriction (CR). The present study has investigated the effect of CR on plasma lipoprotein (a) [Lp(a)], an independent risk factor for the age-associated process of atherosclerosis. Rhesus monkeys were fed a control diet (n=19 males, 12 females) or subjected to CR (n=20 males, 11 females fed 30% less calories) for >2 years. All female animals were premenopausal. Plasma Lp(a) levels in control animals were almost two fold higher for males than females (47+/-9 vs 25+/-5mg/dl mean+/-SEM, p=0.05). CR resulted in a reduction in circulating Lp(a) in males to levels similar to those measured in calorie-restricted females, (27+/-5 vs 24+/-4 mg/dl mean+/-SEM). For all animals, plasma Lp(a) was correlated with total cholesterol (r=0.27, p=0.03) and LDL cholesterol (r=0.50, p=0.0001) whether unadjusted or after adjustment for treatment, gender or group. These studies introduce a new mechanism whereby CR may have a beneficial effect on risk factors for the development of atherosclerosis in primates.     

Closing the gender gap (but not the generation gap) in acute coronary syndromes

• In patients with acute coronary syndromes (ACS) undergoing coronary angiography, elderly women have nearly 50% lower rates of adverse events compared to elderly men, primarily driven by lower cardiovascular mortality.
• Nonelderly men and women patients with ACS have similar risk‐adjusted rates of adverse events.
• Elderly ACS patients have lower rates of and delays in coronary revascularization than younger patients.

     

Elevated serum levels of immunoreactive anionic trypsin (but not cationic trypsin) signals pancreatic disease

Summary Pancreatic juice from most studied species contains two major forms of trypsin, one with anionic electrophoretic mobility and one with cationic mobility. They are referred to as anionic and cationic trypsin(ogen). The purpose of this study was to measure immunoreactive anionic trypsin (irAT) and immunoreactive cationic trypsin (irCT) in sera from patients with pancreatic cancer (n=39) and chronic pancreatitis (n=32) using two specific ELISA methods. Sera from 72 healthy persons were used as controls. Patients with pancreatic cancer showed significantly elevated serum levels of irAT median level 39 vs 20.5 μg/L in the control group (p<0.001). No differences in irCT levels were found. The ratio between irAT and irCT in serum was significantly increased (p<0.001). Patients with chronic pancreatitis showed a wide range of both irAT and irCT levels, but no significant differences compared to the control group. The ratio between irAT and irCT was, however, significantly increased also in this group of patients. The results suggest a nonparallel secretion of anionic and cationic trypsinogen in pancreatic disease. This is a pattern that has been observed in experimental forms of chronic “hyperCCKemia.”     

Atorvastatin lowers lipoprotein(a) but not apolipoprotein(a) fragment levels in hypercholesterolemic subjects at high cardiovascular risk

The effect of statins on Lp(a) levels is controversial; furthermore, the potential action of statins on apo(a) fragmentation is indeterminate. We therefore determined the circulating levels of Lp(a) and of apo(a) fragments in hypercholesterolemic patients before and after treatment (6 weeks) with Atorvastatin 10 mg/day (A10) or Simvastatin 20 mg/day (S20). In a double blind study, hypercholesterolemic patients (n=391) at high cardiovascular risk (LDL-C>=4.13 mmol/l; TG<2.24 mmol/l; 34% with documented CHD; 45% hypertensive; and 29% current smokers) were assigned to treatment with A10 (n=199) or S20 (n=192). Plasma Lp(a) and apo(a) fragment levels (n=206) were measured prior to and after treatment. At baseline, A10 and S20 groups did not differ in plasma levels of lipids, Lp(a) (A10: 0.45+/-0.48 mg/ml, S20: 0.46+/-0.5), and apo(a) fragments (A10: 3.88+/-5.22 microg/ml; S20: 3.25+/-3), and equally in apo(a) isoform size (A10: 26+/-5 kr, S20: 25.5+/-5.3). After treatment, both statins significantly reduced Lp(a) levels (A10: 0.42+/-0.47 mg/ml, 6% variation, P<0.001; S20: 0.45+/-0.53 mg/ml, 0.02% variation, P=0.046). A10 and S20 did not significantly differ in their efficacy to lower Lp(a) levels. In a multivariate logistic regression analysis, the reduction of Lp(a) levels was independently associated with Lp(a) baseline concentration, but not to other variables, including LDL-C reduction. Plasma levels of apo(a) fragments were not modified by either statin. In conclusion, both A10 and S20 significantly lowered Lp(a), although this effect was of greater magnitude in atorvastatin-treated patients.     

Severity of multiple organ failure (MOF) but not of sepsis correlates with irreversible platelet degranulation

Summary Multiple hemostatic changes occur in sepsis and multiple organ failure (MOF). To evaluate the role of platelets in patients with sepsis and MOF, we examined changes in surface glycoproteins on circulating platelets of 14 patients with suspected sepsis and MOF. The severity of sepsis and MOF was assessed by the Elebute and APACHE II scoring systems, respectively. Using flow cytometric techniques and platelet specific monoclonal antibodies, platelet surface expression of fibrinogen receptor on GPIIb-IIIa, of von Willebrand Factor receptor GPIb, and of granule glycoproteins (thrombospondin (TSP), GMP-140, GP53) was measured. Plasma membrane expression of GPIIb-IIIa and GPIb on circulating platelets was not affected by sepsis or MOF. Septic patients, however, showed a significantly elevated fibrinogen receptor activity (LIBS1 expression) (p<0.05) that correlated with severity of disease (r=0.597, p=0.043). No significant change in surface expression of granule glycoproteins (TSP, GMP-140, GP53) was noted in septic patients. In contrast, degranulation of granule glycoproteins was significantly elevated in MOF (p<0.05) which correlated well with severity of MOF (GMP-140, r=0.611, p=0.013; TSP, r=0.643, p=0.026). We speculate that platelets in sepsis circulate in a hyperaggregable but still reversible state that results in increased risk of microthrombotic events. In the course of the disease, irreversible platelet degranulation of adhesion molecules occurs that may play an important role in the development of MOF.

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Schweregrad des Multiorganversagens (MOV) jedoch nicht der Sepsis korreliert mit irreversibler Degranulation zirkulierender Thrombozyten

Zusammenfassung Ziel der vorliegenden Pilotstudie war es, die Thrombozytenfunktion von 14 Intensivpatienten mit unterschiedlicher Ausprägung von Sepsis und Multiorganversagen (MOV) zu untersuchen. Schweregrad der Sepsis und des MOV wurde anhand intensivmedizinischer Scoresysteme (APACHE II, Elebute) beurteilt. Die Thrombozytenfunktion wurde durch durchflußzytometrische Bestimmung von membranständigen Glykoproteinen (GPIIb-IIIa, GPIb, Thrombospondin (TSP), GMP-140, GP53) untersucht. Weder Sepsis noch MOV beeinflußten die Oberflächen-expression von GPIIb-IIIa oder GPIb. Die Aktivierung des Fibrinogenrezeptors war jedoch bei Sepsis deutlich erhöht (p<0.05) und korrelierte signifikant mit dem Schweregrad der Erkrankung (r=0,597, p=0,043). Eine signifikant gesteigerte Degranulation der Thrombozyten bei Sepsis konnte jedoch nicht beobachtet werden. Im Gegensatz dazu war die thrombozytäre Freisetzung von Granula-Glykoproteinen (TSP, GMP-140, GP53) bei MOV deutlich erhöht (p<0,05) und korrelierte mit dem Schweregrad der Erkrankung (GMP-140, r=0,611, p=0,013; TSP, r=0,643, p=0,026). Die Ergebnisse dieser Arbeit zeigen, daß Blutplättchen in Patienten mit Sepsis in einem aktivierten jedoch noch reversiblen Aggregationszustand zirkulieren (Aktivierung des Fibrinogenrezeptors), einhergehend mit einem erhöhten Risiko von Mikrothrombosen. Im Laufe der Erkrankung kann es zur gesteigerten Freisetzung und Oberflächenexpression von thrombozytären Glykoproteinen kommen, die eine entscheidende pathophysiologische Rolle in der Entwicklung von Mikrozirkulationsstörungen und MOV spielen könnten.