Effect of recombinant human interleukin-6 (rhIL-6) and rhIL-3 on hematopoietic regeneration as demonstrated in a nonhuman primate chemotherapy model

Using a recently developed hepsulfam-induced pancytopenia model in rhesus macaques, we have studied the effects of recombinant human interleukin-6 (rhIL-6) and rhIL-3 on marrow regeneration. Control animals were given hepsulfam (1.5 g/m2 by a single 30-minute intravenous [i.v.] injection, n = 4), while study animals received hepsulfam followed by rhIL-6, rhIL-3, or a combination of rhIL-6 and rhIL-3 (n = 3 per study group). Each cytokine was administered by once- daily subcutaneous (SC) injection (15 micrograms/kg/d) for 3 weeks beginning the day after chemotherapy (days 2 through 22). Mean platelet counts in control animals were < 100,000/microL on days 15 through 24, with 50% of the counts < 50,000/microL and two of four animals requiring platelet transfusion. In the rhIL-6- and rhIL-6/rhIL-3- treated groups, the nadir mean platelet counts were 164,000 +/- 58,700/microL and 162,300 +/- 23,800/microL, respectively, and occurred on day 15. Platelet counts in the rhIL-3-treated group were similar to those in controls. Mean absolute neutrophil counts (ANCs) < 1,000/microL occurred on days 10 through 29 in control animals, days 8 through 15 in rhIL-6-treated animals, and days 6 through 8 and 13 in rhIL-6/rhIL-3-treated animals. The frequency of ANCs < 500/microL was significantly less in the rhIL-6- and rhIL-6/rhIL-3-treated groups versus control groups (2.7 +/- 0.6 and 2.0 +/- 1.0 vs 7.0 +/- 1.4 occurrences, respectively; P < .05). rhIL-3-treated animals had ANCs similar to those in controls; one animal died with septicemia on day 21. Monkeys receiving rhIL-6 were significantly more anemic during the cytokine administration period; however, the anemia resolved by day 24. Coadministration of rhIL-3 and rhIL-6 partially corrected the anemia. The data indicate that rhIL-6 prevents significant thrombocytopenia and shortens the neutropenic period in this chemotherapy model.     

Interleukin-6-associated anemia: determination of the underlying mechanism

Recombinant human interleukin-6 (rhIL-6) is a pluripotent cytokine with proinflammatory, antitumor, and growth factor effects. Clinical investigations of rhIL-6 either alone as immunotherapy or as a colony- stimulating factor in conjunction with chemotherapy have shown a dose- dependent, rapid onset, and largely reversible decrease in venous hematocrit levels. In an effort to determine the mechanism for the rhIL- 6-associated anemia, we measured red blood cell volume serially in patients receiving rhIL-6 at either 30 micrograms/kg/day as a 120-hour continuous intravenous infusion (renal cell carcinoma) or 100 micrograms/kg/d intravenously over 1 hour for 5 days (melanoma) as part of two separate phase II trials. Radioisotope dilution assays with 51Cr- labeled autologous red blood cells and hemolysis screens were performed on day 1 before the initiation of therapy and on day 5 shortly before the end of therapy. In the 6 patients studied, the mean decrease in hemoglobin concentration was 1.9 +/- 0.94 g/dL. The mean decrease in the hematocrit level was 6% +/- 2% and the mean increase in total blood volume was 731 +/- 337 mL. These changes were explained by a mean decrease in red blood mass of 106 +/- 109 mL and a mean increase in plasma volume of 743 +/- 289 mL. The decrease in red blood cell mass was largely explained by phlebotomy during the hospitalization, but was not statistically significant (paired t-test, P = .06). All other changes were statistically significant (P < .05). Simple regression analysis indicated that the decrease in hematocrit level and increase in plasma volume were related (y = -1.78 - .0066X; R = -.74). Measurements of lactate dehydrogenase, bilirubin, haptoglobin, and reticulocyte counts and serial stool hemoccults did not indicate hemolysis or blood loss. We conclude that the anemia caused by IL-6 is caused by an increase in plasma volume.     

Increased blood vascular endothelial growth factor levels in patients with acute myocardial infarction

Vascular endothelial growth factor (VEGF) is a growth factor for vascular endothelial cells in vitro. The present study was designed to determine whether serum VEGF levels increase in patients with acute myocardial infarction (AMI) compared with patients with stable exertional angina and control subjects, and to examine the serial changes of serum VEGF levels in patients with AMI. We examined serum VEGF levels by using antibody prepared from serum immunized with human VEGF(121). The serum VEGF level (pg/ml) was higher (p < 0. 0001) on admission in the patients with AMI (177 +/- 19) than in those with stable exertional angina (61 +/- 7) and control subjects (62 +/- 6). The serum VEGF level (pg/ml) of the patients with AMI was 177 +/- 19 on admission, 125 +/- 9 on day 3, 137 +/- 11 on day 5, 242 +/- 18 at 1 week, and 258 +/- 22 at 2 weeks after admission. The value was higher on admission than on day 3 after admission (p = 0.014), the values were higher at 1 week and 2 weeks than on admission, on day 3, and 5 (p < 0.01). Furthermore, there were correlations between peak VEGF levels at 1 week or 2 weeks after admission and peak creatine kinase levels. The increase of VEGF on admission in the patients with AMI may be due to the hypoxia of acute myocardial ischemia. The elevation at 1 week and 2 weeks from the onset may cause the development of collateral circulation in relation to the healing of the infarction site.     

Sustained increase in haemoglobin and RBC following long-term administration of recombinant human erythropoietin to patients with homozygous beta-thalassaemia

Summary. Recombinant human erythropoietin (rHuEPO) was given subcutaneously three times per week in an escalating dose from 500u/kg to 950u/kg together with ferrous fumarate 305 mg and folic acid 5mg/d, to 10 patients from four unrelated Arab families with homozygous /3-thaIassaemia. Six splenectomized patients showed a mean (istandard error) increase in haemoglobin from 7-1 – 0-1 to 9-3 – 0-1 g/dl (P = 0-0001), in RBC from 4-0 to 5-0 × 10¹²/1 (P = 0-0001) and in nucleated RBC from 32 – 7 × 10¹⁰/1 to 82–6 × 10¹⁰/1 while receiving 750u/kg three times per week which persisted for 4-11 months. In two patients there was no need for further blood transfusions. In three out of four unsplenectomized patients there were no changes in Hb and RBC despite dose escalation. There were no significant changes in MVC, MCH and reticulocyte count, serum bilirubin, LDH, malonyldialdehyde (MDA) and vitamin E levels. After 13 weeks of rHuEPO there was a mean increase in the percentage of F cells from 31 –10% to 86 –6% (P< 0-003) in three splenectomized patients and in one unsplenectomized patient from 56-4% to 80% without changes in the levels of Hb F. Globin chain synthesis ratios did not change in four responding patients. Mean serum iron and transferrin saturation index did not change, whereas mean serum ferritin increased from 299–45/ng/I to 480–20/ig/l (P< 0-001). In seven responding patients an accelerated linear growth was indicated by positive changes in height standard deviation score for chronological age. Side-effects were minimal throughout the treatment period.     

Restoration of thrombolytic potential in plasminogen-deficient mice by bolus administration of plasminogen

Homozygous plasminogen-deficient (Plg-/-) mice had a significantly reduced thrombolytic capacity toward intravenously injected 125I-fibrin labeled plasma clots prepared from Plg-/- murine plasma (9% +/- 3% lysis after 8 hours; (mean +/- SEM, n = 6), as compared with 82% +/- 8% in wild-type mice; P < .0001). Bolus injection of 1 mg purified murine plasminogen in 10- to 17-week-old Plg-/- mice increased the plasminogen antigen and activity levels at 8 hours to normal levels (130 +/- 5 micrograms/mL). Plasminogen administration was associated with significant restoration of thrombolytic potential (64% +/- 7% spontaneous clot lysis; P < .0001 versus lysis without plasminogen injection). Bolus injection of 1 mg plasminogen in homozygous tissue- type plasminogen activator-deficient (t-PA-/-) mice doubled the plasminogen antigen and activity levels after 8 hours and increased 125I-fibrin clot lysis at 8 hours from 13% +/- 3% to 34% +/- 5% (P = .008). Fibrinogen, t-PA antigen and alpha 2-antiplasmin activity levels after 8 hours were not significantly different in the groups with or without plasminogen injection. Injection of plasminogen induced a variable increase (on average 7- to 10-fold) of PAI-1, but no correlation with the extent of spontaneous clot lysis was observed. Histopathologic examination at the end of the experiments revealed that fibrin deposition in the liver of Plg-/- mice was slightly reduced 8 hours after bolus plasminogen injection (P = .007) and markedly reduced after 24 hours (P < .0001). Plasminogen antigen levels in liver extracts were comparable with those found in wild-type mice at 8 hours (130 +/- 20 versus 110 +/- 15 ng/mg protein) and decreased to 25 +/- 3.2 ng/mg protein at 24 hours. Thus, restoration of normal plasminogen levels in Plg-/- mice normalized the thrombolytic potential toward experimentally induced pulmonary emboli, and resulted in removal of endogenous fibrin deposits within 24 hours.     

Disulfiram treatment increases plasma and red blood cell acetaldehyde in abstinent alcoholics

BACKGROUND: Much of alcohol's toxicity is due to its product, acetaldehyde. The role of acetaldehyde derived from endogenous sources was assessed in alcoholic patients administered disulfiram, an inhibitor of aldehyde dehydrogenase. METHODS: The first part of the study included 23 subjects without biochemical or clinical evidence of chronic liver disease who were abstinent for 2 weeks; 11 patients were started on disulfiram (250 mg/day), whereas the other 12 were not given disulfiram and served as controls. The second part of the study included 13 alcoholic patients with clinical or pathological evidence of cirrhosis who also were administered disulfiram for 2 weeks. Plasma and red blood cell (RBC) acetaldehyde as well as serum transaminases were measured at baseline and after 1 and 2 weeks of treatment. RESULTS: In the disulfiram-treated group of alcoholics without known cirrhosis, RBC acetaldehyde levels increased from the pretreatment value of 2.98+/-0.18 microM to 4.14+/-0.33 microM after 1 week and to 4.14+/-0.26 microM after 2 weeks of treatment (p < 0.001). Compared with the pretreatment values (2.07+/-0.24 microM), plasma acetaldehyde levels also increased after 1 week (3.18+/-0.32 microM) and 2 weeks (3.15+/-0.26 microM) of disulfiram treatment (p < 0.001). There were no significant differences in sequential levels measured in either plasma or RBC acetaldehyde levels in patients who were not administered disulfiram. In the group of cirrhotic patients, the mean baseline RBC acetaldehyde value (3.60+/-0.22 microM) was significantly higher than in noncirrhotics. Disulfiram therapy increased the RBC acetaldehyde after 1 week (4.63+/-0.27 microM, p < 0.001) and 2 weeks of treatment (4.06+/-0.28 microM, p < 0.05). Compared with baseline values, plasma acetaldehyde levels were significantly higher after 1 week but not after 2 weeks of disulfiram. There were no significant differences among serum transaminases in alcoholics administered disulfiram, although three cirrhotic patients did have clinically significant elevations. CONCLUSIONS: In abstaining subjects given disulfiram, acetaldehyde concentrations increase, possibly due to diminished catabolism of endogenously generated acetaldehyde. Disulfiram should be given cautiously, especially in patients with cirrhosis.     

Metformin reduces weight, centripetal obesity, insulin, leptin, and low-density lipoprotein cholesterol in nondiabetic, morbidly obese subjects with body mass index greater than 30.

We studied 31 nondiabetic, habitually (> or =5 years) morbidly obese subjects (mean +/- SD body mass index [BMI] 43 +/- 8.7, median 43). Our specific aim was to determine whether metformin (2.55 g/d for 28 weeks) would ameliorate morbid obesity and reduce centripetal obesity; lipid and lipoprotein cholesterol, insulin, and leptin levels; and plasminogen activator inhibitor activity (PAI-Fx), risk factors for coronary heart disease (CHD). The patients were instructed to continue their prestudy dietary and exercise regimens without change. After 2 baseline visits 1 week apart, the 27 women and 4 men began receiving metformin, 2.55 g/d, which was continued for 28 weeks with follow-up visits at study weeks 5, 13, 21, and 29. Daily food intake was recorded by patients for 7 days before visits then reviewed with a dietitian. Kilocalories per day and per week were calculated. At each visit, fasting blood was obtained for measurement of lipid profile, insulin, leptin, and PAI-Fx. The mean +/- SD kilocalories consumed per day, 1,951 +/- 661 at entry, fell by week 29 to 1,719 +/- 493 (P =.014) but did not differ at weeks 5, 13, and 21 from that at week 29 (P >.2). Weight fell from 258 +/- 62 pounds at entry to 245 +/- 54 pounds at week 29 (P =.0001). Girth was reduced from 51.8 +/- 6.2 to 49.2 +/- 4.5 inches (P =.0001). Waist circumference fell from 44.0 +/- 6.4 inches to 41.3 +/- 5.9 (P =.0001). The waist/hip ratio fell from 0.85 +/- 0.09 to 0.84 +/- 0.09 (P =.04). Fasting serum insulin, 28 +/- 15 microU/mL at entry, fell to 21 +/- 11 microU/mL at week 29 (P =.0001), and leptin fell from 79 +/- 33 ng/mL to 55 +/- 27 ng/mL (P =.0001). On metformin, there were linear trends in decrements in weight, girth, waist circumference, waist/hip ratio, insulin, and leptin throughout the study period (P <.007). Low-density lipoprotein (LDL) cholesterol, 126 +/- 34 mg/dL at study entry, fell to 112 +/- 43 mg/dL at week 29 (P =.001), with a linear trend toward decreasing levels throughout (P =.036). By stepwise linear regression, the higher the entry weight, the larger the reduction in weight on metformin therapy (partial R(2) = 31%, P =.001). The greater the reduction in kilocalories consumed per day, the greater the decrease in weight on metformin therapy (partial R(2) = 15%, P =.011). The higher the waist/hip ratio at entry, the greater its reduction on metformin therapy (partial R(2) = 11%, P =.004). The higher the entry serum leptin, the greater its reduction on metformin therapy (partial R(2) = 29%, P =.002). The greater the reduction in insulin on metformin, the greater the reduction in leptin (partial R(2) = 8%, P =.03). The higher the entry PAI-Fx, the greater the reduction in PAI-Fx on metformin (partial R(2) = 43%, P =.0001). Metformin safely and effectively reduces CHD risk factors (weight, fasting insulin, leptin, LDL cholesterol, centripetal obesity) in morbidly obese, nondiabetic subjects with BMI > 30, probably by virtue of its insulin-sensitizing action.     

Postpartum anemia I: definition,prevalence, causes,and consequences

This review provides a status on the definition, prevalence, causes, and consequences of anemia in women who have given childbirth, i.e., postpartum anemia. The diagnosis of iron deficiency anemia relies on a full blood count including hemoglobin, serum ferritin, and serum soluble transferrin receptor, which appear to be reliable indicators of anemia and iron status 1 week postpartum while serum transferrin saturation is an unreliable indicator several weeks after delivery. It is recommended that postpartum anemia should be defined by hemoglobin <110 g/L at 1 week postpartum and <120 g/L at 8 weeks postpartum. The major causes of postpartum anemia are prepartum anemia combined with acute bleeding anemia due blood losses at delivery. Normal peripartum blood losses are approximately 300 ml, but hemorrhage >500 ml occur in 5–6% of the women. In healthy women after normal delivery, the prevalence of anemia (hemoglobin <110 g/L) 1 week postpartum is 14% in iron-supplemented women and 24% in non-supplemented women. In consecutive series of European women, the prevalence of anemia 48 h after delivery is approximately 50%. In developing countries, the prevalence of postpartum anemia is in the range of 50–80%. Postpartum anemia is associated with an impaired quality of life, reduced cognitive abilities, emotional instability, and depression and constitutes a significant health problem in women of reproductive age.     

Defective iron supply for erythropoiesis and adequate endogenous erythropoietin production in the anemia associated with systemic-onset juvenile chronic arthritis

Systemic-onset juvenile chronic arthritis (SoJCA) is associated with high levels of circulating interleukin-6 (IL-6) and is frequently complicated by severe microcytic anemia whose pathogenesis is unclear. Therefore, we studied 20 consecutive SoJCA patients with hemoglobin (Hb) levels <12 g/dL, evaluating erythroid progenitor proliferation, endogenous erythropoietin production, body iron status, and iron supply for erythropoiesis. Hb concentrations ranged from 6.5 to 11.9 g/dL. Hb level was directly related to mean corpuscular volume (r = .82, P < .001) and inversely related to circulating transferrin receptor (r = - .81, P < .001) suggesting that the severity of anemia was directly proportional to the degree of iron-deficient erythropoiesis. Serum ferritin ranged from 18 to 1,660 microgram/L and was unrelated to Hb level. Bone marrow iron stores wore markedly reduced in the three children investigated, and they also showed increased serum transferrin receptor and normal-to-high serum ferritin. All 20 patients had elevated IL-6 levels and normal in vitro growth of erythroid progenitors. Endogenous erythropoietin (epo) production was appropriate for the degree of anemia as judged by both the observed to predicted log (serum epo) ratio 10.95 +/- 0.12) and a comparison of the serum epo- Hb regression found in these subjects with that of thalassemia patients. Multiple regression analysis showed that serum transferrin receptor was the parameter most closely related to hemoglobin concentration: variation in circulating transferrin receptor explained 61% of the variation in Hb level (P < .001). In 10 severely anemic patients, amelioration of anemia following intravenous iron administration resulted in normalization of serum transferrin receptor. Defective iron supply to the erythron rather than blunted epo production is the major cause of the microcytic anemia associated with SoJCA. A true body-iron deficiency caused by decreased iron absorption likely complicates long-lasting inflammation in the most anemic children, and this can be recognized by high serum transferrin receptor levels. Although oral iron is of no benefit, intravenous iron saccharate is a safe and effective means for improving iron availability for erythropoiesis and correcting this anemia. Thus, while chronically high endogenous IL-6 levels do not appear to blunt epo production, they are probably responsible for the observed abnormalities in iron metabolism. Anemia of chronic disease encompasses a variety of anemic conditions whose peculiar features may specifically correlate with the type of cytokine(s) predominantly released.     

Macroprolactinoma shrinkage during cabergoline treatment is greater in naive patients than in patients pretreated with other dopamine agonists: a prospective study in 110 patients

To investigate whether previous treatment with bromocriptine (BRC) or quinagolide (CV) impairs a subsequent response to long-term cabergoline (CAB) treatment, we prospectively studied 110 patients with macroprolactinoma. Four groups of patients were considered: 1) naive: 26 untreated patients with a mean serum PRL levels of 1013.4 +/- 277.7 microg/L (+/- SEM; range, 185.5-5611 microg/L); 2) intolerant: 19 patients previously shown to be intolerant of BRC treatment with a mean serum PRL level of 539.4 +/- 172.2 microg/L (range, 174-3564 microg/L); 3) resistant: 37 patients shown to be resistant/hyporesponsive to BRC, CV, or both, with a mean serum PRL level of 602.6 +/- 136.8 microg/L (range, 148-3511 microg/L); and 4) responsive: 28 patients previously treated with BRC or CV for 1-5 yr, achieving normoprolactinemia and restoration of gonadal function, but no longer treated with BRC or CV because of poor compliance or because the drug was not available. After a 15- to 30-day washout period, the serum PRL level was 397 +/- 43.1 microg/L (140-978 microg/L). CAB treatment was given at doses ranging 0.25-3.5 mg weekly for 1 yr to 110 patients, for 2 yr to 104 patients, and for 3 yr to 81 patients. Magnetic resonance imaging was performed before and after 12, 24, and 36 months of CAB treatment to evaluate significant tumor shrinkage (>80% reduction of pretreatment tumor volume). Among the 26 naive patients, normoprolactinemia was achieved in 21 (80.8%) after 1-6 months at 0.25-2 mg/week and in 5 patients after 24 months at 0.5-3 mg/week. Tumor volume was reduced from 1431.5 +/- 310.3 to 47.2 +/- 21.5 mm3 (P < 0.0001); average tumor shrinkage was 92.1 +/- 2.9%; significant tumor shrinkage was observed in 92.3% of patients, and tumor mass completely disappeared in 16 patients (61.5%). Among the 19 intolerant patients, normoprolactinemia was achieved in 18 (94.7%) after 1-6 months of CAB treatment at 0.25-1 mg/week. One patient remained mildly hyperprolactinemic. Tumor volume was reduced from 1925 +/- 423.1 to 842.0 +/- 330.7 mm3 (P < 0.001); average tumor shrinkage was 66.2 +/- 6.4%; significant tumor shrinkage was obtained in 42.1% of patients, and tumor mass completely disappeared in 4 patients (21%). Among the 37 resistant patients, normoprolactinemia was achieved in 19 (51.3%) after 6-12 months at 1-2 mg/week and in the remaining 18 patients after 18-24 months at 3-3.5 mg/week. Tumor volume was reduced from 1208.0 +/- 173.7 to 471.2 +/- 87.3 mm3 (P < 0.005); average tumor shrinkage was 58.4 +/- 4.9%; significant tumor shrinkage was obtained in 10 of 33 patients (30.3%), and in no patient did tumor mass completely disappear. Among the 28 responsive patients, normoprolactinemia was achieved in 23 (82.1%) after 1-6 months at 1-2 mg/week and in 5 patients after 12 months at 3 mg/week. Tumor volume was reduced from 1351.3 +/- 181.5 to 757.1 +/- 193.6 mm3 (P < 0.01); average tumor shrinkage was 59.2 +/- 6.2%; significant tumor shrinkage was obtained in 10 of 26 patients (38.4%), and tumor mass completely disappeared in 4 patients (15.4%). Nadir PRL levels and percent tumor shrinkage during CAB treatment in naive patients were significantly lower (P < 0.001) and higher (P < 0.001), respectively, than those in the remaining three groups, and the average weekly dose of CAB in resistant patients was significantly higher (P < 0.001) than that in the remaining three groups. A significant association was found between tumor shrinkage and previous treatments (chi2 = 27.1; P < 0.0001). At the multistep correlation analysis, nadir PRL levels were the strongest predictors of tumor shrinkage (r2 = 0.556; P < 0.0001), followed by CAB dose (r2 = 0.577; P < 0.0001). The tolerability was excellent in 105 patients (95.4%). In conclusion, the prevalence of macroprolactinoma shrinkage after CAB treatment at standard doses for 1-3 yr was higher in naive patients (92.3%) than in intolerant (42.1%), resistant (30.3%), and responsive patients (38.4%). Thus, C     

Red blood cell regeneration induced by subcutaneous recombinant erythropoietin: iron-deficient erythropoiesis in iron-replete subjects [see comments]

Limited red blood cell (RBC) regeneration often prevents collection of sufficient blood from autologous donors. We studied the effects of subcutaneous recombinant erythropoietin (rEPO) in subjects making frequent blood donations. Six healthy iron-replete male subjects took rEPO (200 U/kg) subcutaneously daily, and donated blood (450 mL) twice a week for 3 weeks. During a control study, these subjects also attempted twice-weekly blood donations without rEPO. Four other males given rEPO, including one with idiopathic hemochromatosis, waited until day 8 to begin blood donations. All healthy subjects took oral ferrous sulfate. Subcutaneous rEPO given with blood donations resulted in a marked reticulocytosis (mean peak value 568 +/- 159 x 10(9)/L v 235 +/- 77 x 10(9)/L, control study; P < .05), and enhanced RBC production at 28 days (1,208 +/- 227 mL v 719 +/- 161 mL, P < .05). rEPO in advance of blood donations was slightly less effective in normal subjects (941 +/- 139 mL, P < .05); however, the subject with hemochromatosis produced substantially more RBCs (1,764 mL) than any normal subject. rEPO-treated normal subjects (but not the rEPO-treated patient with hemochromatosis or untreated controls) produced iron-deficient RBCs with elevated zinc protoporphyrin levels and low hemoglobin content. These cells appeared within 1 week of rEPO administration and before laboratory confirmation of depleted iron stores. Thus, subcutaneous rEPO is an effective stimulant of erythropoiesis in nonanemic blood donors. However, in addition to eventual depletion of iron stores, early functional iron deficiency affects response to the drug.     

Marrow accessory cell infection and alterations in hematopoiesis accompany severe neutropenia during experimental acute infection with feline immunodeficiency virus

Severe neutropenia and bone marrow (BM) morphologic abnormalities occur during experimentally induced primary infection with feline immunodeficiency virus (FIV), a lentivirus biologically similar to human immunodeficiency virus (HIV). To further characterize the mechanisms involved in this acute infection model of lentivirus-induced BM suppression, peripheral blood counts, histologic BM studies, and BM culture assays were performed on 12 cats that underwent necropsy at regular intervals postinoculation (PI) with FIV Petaluma. Plasma viremia developed at week 3 PI and neutropenia was initially detected at week 6 PI. Low neutrophil counts, but normal hematocrits and platelet counts, persisted through week 12 PI. Infected BM mononuclear cells and megakaryocytes were identified by in situ hybridization assays for FIV nucleic acids in BM sections of cats that underwent necropsy at weeks 4 to 12 PI, correlating with detection of soluble FIV p24 antigen and identification of infected mononuclear and macrophage cells in BM buffy-coat cell cultures from these cats. At weeks 1.5 to 4 PI, the mean frequencies (number per 10(5) BM mononuclear cells) of erythroid progenitors (erythroid colony-forming units [CFU-E] and erythroid burst-forming units [BFU-E] and granulocyte/macrophage progenitors (CFU-granulocyte/macrophage [CFU-GM]) were increased to 508 +/- 74, 143 +/- 24, and 110 +/- 17, respectively (n = 5 cats) as compared with controls (172 +/- 24, 86 +/- 26, and 44 +/- 10; n = 3 cats; P < .02), and the percentages of progenitors in the DNA-synthetic phase of the cell cycle were equivalent to controls. In contrast, the progenitor frequencies at weeks 6 to 12 PI were significantly decreased (72 +/- 16, 43 +/- 6, and 19 +/- 4, respectively; n = 7 cats; P < .01), and these progenitors were more frequently in S-phase. Autologous serum significantly inhibited (P < .05) the growth of CFU-GM in 6 of 9 cats and failed to support the maximal growth of BFU-E in 4 of 9 cats studied at weeks 4 to 12 PI, whereas no such abnormalities were observed in colony assays containing autologous sera from control cats (n = 3) or cats studied at weeks 1.5 or 3 PI (n = 3). In comparison, sera from FIV-infected cats did not inhibit the growth of normal, allogeneic progenitors. However, FIV serum frequently failed to support maximal in vitro growth of normal CFU-GM as compared with uninfected allogeneic sera, further suggesting a lack of progenitor growth- promoting substances in infected cat sera.(ABSTRACT TRUNCATED AT 400 WORDS)     

Effectiveness of Switching From Intravenous to Subcutaneous Infliximab in Patients With Inflammatory Bowel Diseases: the REMSWITCH Study

Background and AimsWe assessed the effectiveness of switching from intravenous to subcutaneous infliximab in patients with inflammatory bowel diseases (IBDs) treated with or without intensified intravenous regimen.MethodsIn this multicenter observational study, IBD patients in clinical remission (partial Mayo score ≤2 or Harvey-Bradshaw index ≤4) were switched to a unique dose of subcutaneous infliximab (120 mg every other week). Pharmacological and biological data were collected at baseline, visit 1 (4–8 weeks postswitch), visit 2 (8–16 weeks postswitch), and visit 3 (16–24 weeks postswitch). Relapse was defined as clinical relapse or fecal calprotectin increase ≥150 μg/g compared with baseline.ResultsAmong 184 eligible patients, 72.3% (n = 133 of 184) agreed to switch to subcutaneous infliximab. At visit 3, a relapse occurred in 10.2% (n = 6 of 59), 7.3% (n = 3 of 38), 16.7% (n = 3 of 18), and 66.7% (n = 10 of 15) (P < .001) of patients receiving 5 mg/kg every 8 weeks, 10 mg/kg every 8 weeks, 10 mg/kg every 6 weeks, and 10 mg/kg every 4 weeks, respectively. Dose escalation to 240 mg every other week led to recapture clinical remission in 93.3% (n = 14 of 15). Infliximab serum levels increased after the switch (P < .0001) except for patients receiving 10 mg/kg every 4 weeks. In multivariable analysis, 10 mg/kg every 4 weeks regimen (odds ratio, 12.4; 95% confidence interval, 1.6–98.4; P = .017) and fecal calprotectin >250 μg/g at baseline (odds ratio, 5.4; 95% confidence interval, 1.1–27.6; P = .042) had a higher risk of relapse as well as reduced (41.7%) or stable (36.8%) infliximab serum levels between baseline and visit 1 compared with increased serum levels (12.7%) (P = .020 and P = .019, respectively). Patients’ acceptability (10-point scale) was improved by the switch (6.9 ± 1.6 vs 8.6 ± 1.4; P < .0001). No severe adverse event was reported.ConclusionsSwitching from intravenous to subcutaneous infliximab 120 mg every other week is safe and well accepted, leading to a low risk of relapse in IBD patients except for those receiving 10 mg/kg every 4 weeks requiring 240 mg every other week.     

Serum C-reactive protein elevation in left ventricular remodeling after acute myocardial infarction--role of neurohormones and cytokines

BACKGROUND: We previously reported that increased peak serum C-reactive protein (CRP) level after acute myocardial infarction (AMI) was a major predictor of cardiac rupture and long-term outcome. The aim of this study was to clarify the role of serum CRP elevation as a possible marker of left ventricular (LV) remodeling after AMI. METHODS: We prospectively studied 31 patients who underwent primary angioplasty for a first anterior Q-wave AMI. Peak serum CRP level was determined by serial measurements after admission. LV volume and the plasma levels of various neurohormones and cytokines were measured on admission, and 2 weeks and 6 months after AMI. RESULTS: Patients with higher peak CRP levels (above the median) had a greater increase in LV end-diastolic volume during 2 weeks after AMI (+21+/-14 vs. +5+/-6 ml/m(2), P=0.001) and a lower ejection fraction (45+/-11 vs. 53+/-7%, P=0.02) than those with lower CRP levels, associated with a higher incidence of pump failure, atrial fibrillation, and LV aneurysm. Plasma levels of norepinephrine, brain natriuretic peptide, and interleukin-6 2 weeks after AMI were higher in the high CRP group than in the low CRP group. CONCLUSIONS: Increased peak serum CRP level was associated with a greater increase in LV volume after anterior AMI. Plasma norepinephrine and interleukin-6 levels were increased in patients with higher CRP levels, suggesting a possible role of sympathetic activation and enhanced immune response in the development of LV remodeling after AMI.     

In vivo effects of recombinant human interleukin-6 in primates: stimulated production of platelets

In cynomolgus monkeys, twice daily subcutaneous injections of recombinant human interleukin-6 (rhIL-6) at doses of 5 to 80 micrograms/kg/d for 14 consecutive days caused dose-dependent increases in platelet count, usually continuing for more than 1 week after cessation of the injections. The count reached a level approximately twofold or more above the preinjection level even at 5 micrograms/kg/d, and at doses of more than 20 micrograms/kg/d, the increase became biphasic with a higher second peak 3 days after cessation of the injections. Morphologic analysis of the bone marrow after the 7 day-injections with 80 micrograms/kg/d revealed a marked increment in size of megakaryocytes compared with control, indicating the promotion of megakaryocyte maturation. Other changes attributable to the rhIL-6 treatment include dose-dependent loss of body weight, anemia, neutrophilia and monocytosis, elevation of serum C-reactive protein and alpha-1 acid glycoprotein levels, and decrease of serum albumin; all of which returned to normal within 1 week after cessation of the injections and were tolerable at doses of less than 10 micrograms/kg/d. These findings suggest that rhIL-6 may be an effective strategy for the treatment of thrombocytopenia.     

Factors affecting volume reduction and red blood cell depletion of bone marrow on the COBE Spectra cell separator before haematopoietic stem cell transplantation

The COBE Spectra is used to volume/red blood cell (RBC) deplete BM before transplantation or cryopreservation. We have audited our results to identify the effect of transit time, refrigerated storage, age and cellular composition on mononuclear cells (MNC) and CD34+ cell recoveries, volume/RBC depletion and neutrophil engraftment. In total, 88 consecutive collections from autologous (n = 25) and allogeneic (n = 63) donors were included. The mean collection volume was 1250 +/- 398 ml with RBC content of 341 +/- 113 ml. The MNC and CD34+ cell recoveries were 83.3 +/- 18.5 and 88.1 +/- 18.9%, respectively, volume depletion was 88.2+/-4.4% and RBC depletion 98.3 +/- 1.8%. Neutrophil engraftment was achieved in 20.1 +/- 6.4 days. Factors affecting MNC and CD34+ cell recoveries were transit time (P = 0.0060), overall age (P < 0.0210) and MNC/CD34+ cell concentrations (P < 0.0313). The presence of crenated RBC also reduced CD34+ cell recovery (P = 0.0028). Refrigerated storage did not adversely affect cell recovery (P > 0.8161) or neutrophil engraftment (P = 0.8959). This study demonstrates that time in transit, overall age, MNC and CD34+ cell concentrations and RBC condition were important factors affecting processing. RBCs show artefacts soon after collection at ambient temperatures and these may interfere with the separation and collection of MNC/CD34+ cells. Refrigeration at 4-6 degrees C during transit and storage may reduce formation of RBC artefacts and maximize MNC and CD34+ cell recoveries.     

Protective effect of rhIL-1β on pancreatic islets of alloxan-induced diabetic rats

AIM: To observe the protective effect of rhIL-1β on pancreatic islets of alloxan-induced diabetic rats. METHODS: Protection of rhIL-1β on pancreatic islets of alloxan-induced diabetic rats (n=5) was demonstrated with methods of immunohistochemistry and stereology. The concentration of serum glucose was measured by GOD method and that of serum insulin by RIA. RESULTS: The concentration of serum glucose increased but that of insulin decreased after administration of alloxan (150mg/kg), and the volume density and numerical density of the islets were zero. In rhIL-1β pretreated rats, although the concentration of serum insulin decreased (from 11.9&#177;3.0mIU/L to 6.1&#177;1.6mIU/L,P&lt;0.05), that of glucose was at normal level compared with the control group. As compared with alloxan group, the concentration of serum glucose in rhIL-1β pretreated rats decreased (from 19.4&#177;8.9mmol/L to 12.0&#177;4.0mmol/L, P&lt;0.05) and the volume density increased(0/L to. 1/L, P&lt;0.05). CONCLUSION: rhIL-1β pretreatment may have protective effect on the islets of alloxan-induced diabetic rats.     

Randomized, double blind controlled trial of subcutaneous recombinant human interleukin-11 versus prednisolone in active Crohn's disease

BACKGROUND: Interleukin-11 has shown benefit in animal inflammatory bowel disease models. Recently, recombinant human interleukin-11 (rhIL-11) has been observed to induce remission in a subset of patients with mild to moderate Crohn's disease (CD). The present study compared the efficacy of rhIL-11 versus prednisolone in remission induction in CD. METHODS: Patients with active CD were randomly assigned to receive either subcutaneous rhIL-11 (1 mg once weekly) and prednisolone placebo tablets, or active prednisolone (60 mg/day) and rhIL-11 placebo, for 12 weeks. Prednisolone/placebo was tapered after week 1, and patients were assessed every second week. RESULTS: Fifty-one patients received medication: 13/27 (rhIL-11) and 17/24 (prednisolone) completed 12 weeks of treatment. Remission rates (intent to treat) for rhIL-11 versus prednisolone were 4% versus 46% at week 4 (p < 0.001) and 19% versus 50% at week 6 (p < 0.05). Response to treatment (deltaCDAI > 100) was seen in 19% (rhIL-11) versus 63% (prednisolone) after 4 weeks (p < 0.002) and 37% versus 63% after 6 weeks (p = 0.1). After 12 weeks of treatment, it was observed that 22% (rhIL-11) versus 21% (prednisolone) had remained in remission. Frequent side effects of rhIL-11 included fever (n = 3), rash (4), arthralgia/arthritis (3), nausea/vomiting (3), and headache (6). CONCLUSION: rhIL-11 is well tolerated but significantly inferior when compared to prednisolone in short-term remission induction in patients with active CD. In this patient cohort, both treatments appeared to be poor in maintaining remission over a period of 3 months.     

Carbohydrate-deficient transferrin, a sensitive marker of chronic alcohol abuse, is highly influenced by body iron

Carbohydrate-deficient transferrin (CDT), a microheterogeneous form of serum transferrin (Tf), has been proposed as the most reliable marker of chronic alcohol consumption, although unexplained false-positive and -negative results have been reported. We investigated whether body iron influenced CDT serum levels by studying alcohol abusers with or without iron overload and nonabusers with iron deficiency or iron overload caused by genetic hemochromatosis (GH). In alcohol abusers, CDT was significantly lower in the presence of iron overload than in the absence (24.6 +/- 16.5 U/L vs. 33.3 +/- 11.7 U/L; P <.01), with false-negative results almost exclusively in patients with iron overload. Similarly, in nonabusers with GH, CDT was lower than in normal controls (9.6 +/- 2. 2 U/L vs. 15.7 +/- 3.3 U/L; P <.0001), whereas, patients with iron deficiency anemia had significantly higher levels than controls (28. 1 +/- 5.8 U/L vs. 15.7 +/- 3.3 U/L; P <.0001). In nonabusers, iron supplementation therapy significantly decreased CDT levels in patients with iron deficiency anemia (33.7 +/- 6.6 U/L vs. 21.7 +/- 5.2 U/L; P =.0007), while iron-depletion treatment significantly increased CDT levels in patients with GH (9.7 +/- 2.0 U/L vs. 14.7 +/- 4.0 U/L; P =.001). Alcohol abusers had a significant relationship between liver iron concentration (LIC) and the reciprocal of CDT (r =.65; P <.0001), while in nonabusers, there was a significant correlation between Tf and CDT (r =.72; P <.0001). In conclusion, CDT serum levels are markedly affected by the patient's iron status, with iron overload reducing its sensitivity in alcohol abusers and iron deficiency its specificity in nonabusers. CDT can be considered a reliable marker of alcohol abuse only when iron stores are normal.