Granulocyte colony-stimulating factor administration to healthy volunteers: analysis of the immediate activating effects on circulating neutrophils

In four healthy volunteers, we analyzed in detail the immediate in vivo effects on circulating neutrophils of subcutaneous administration of 300 micrograms of granulocyte colony-stimulating factor (G-CSF). Neutrophil activation was assessed by measurement of degranulation. Mobilization of secretory vesicles was shown by a decrease in leukocyte alkaline phosphatase content of the circulating neutrophils. Furthermore, shortly postinjection, Fc gamma RIII was found to be upregulated from an intracellular pool that we identified by immunoelectron microscopy as secretory vesicles. Intravascular release of specific granules was shown by increased plasma levels of lactoferrin and by upregulation of the expression of CD66b and CD11b on circulating neutrophils. Moreover, measurement of fourfold elevated plasma levels of elastase, bound to its physiologic inhibitor alpha 1- antitrypsin, indicated mobilization of azurophil granules. However, no expression of CD63, a marker of azurophil granules, was observed on circulating neutrophils. G-CSF--induced mobilization of secretory vesicles and specific granules could be mimicked in whole blood cultures in vitro, in contrast to release of azurophil granules. Therefore, we postulate that the most activated neutrophils leave the circulation, as observed shortly postinjection, and undergo subsequent stimulation in the endothelial microenvironment, resulting in mobilization of azurophil granules. Our data demonstrate that G-CSF should be regarded as a potent immediate activator of neutrophils in vivo.     

High-dose etoposide and cyclophosphamide without bone marrow transplantation for resistant hematologic malignancy

Seventy-five patients with resistant acute leukemia or lymphoma received high-dose cyclophosphamide and etoposide to explore the activity of this combination in resistant hematologic malignancies, and to determine the maximum doses of these drugs that can be combined without bone marrow transplantation. Etoposide was administered over 29 to 69 hours by continuous infusion corresponding to total doses of 1.8 g/m2 to 4.8 g/m2. Cyclophosphamide, 50 mg/kg/d, was administered on 3 or 4 consecutive days total 150 to 200 mg/kg ideal body weight). At all dose levels myelosuppression was severe but reversible. Mucosal toxicity was dose-limiting with the maximum tolerated dose level combining etoposide 4.2 g/m2 with cyclophosphamide 200 mg/kg. Continuous etoposide infusion produced stable plasma levels that were lower than would be achieved after administration by short intravenous infusion, and this could explain our ability to escalate etoposide above the previously reported maximum tolerated dose. There were 28 complete (35%) and 12 partial (16%) responses. Median duration of complete response (CR) was 3.5 months (range 1.1 to 20+). Seventeen of 40 patients (42%) with acute myelogenous leukemia (AML) achieved CR, including 6 of 20 (30%) with high-dose cytosine arabinoside resistance. We conclude that bone marrow transplantation is not required after maximum tolerated doses of etoposide and cyclophosphamide. This regimen is active in resistant hematologic neoplasms, and the occurrence of CR in patients with high-dose cytosine arabinoside-resistant AML indicates a lack of complete cross-resistance between these regimens.     

Attentional and Interpretational Biases Toward Pain-Related Stimuli in Children and Adolescents: ASystematic Review of the Evidence

This review investigated whether youth exhibit attention or interpretation biases toward pain-related information and whether such biases are more pronounced in youth with chronic pain. Three databases were searched to identify studies that assessed attention or interpretation biases using an accepted experimental paradigm. Ten studies were identified, 8 examining attentional biases and 2 examining interpretation biases. As in the adult literature, there was no evidence of attentional biases toward pain in youth without chronic pain. Three studies investigating youth without chronic pain found evidence for relationships between catastrophizing or anxiety and indicators of vigilance or avoidance (in 2 cases, for youth with low self-reported attentional control). For attentional biases, 5 studies compared youth with and without chronic pain. Two of these studies measured cortical correlates and found evidence of neurologic activity indicating a bias in orienting to pain-related stimuli. Three studies examined biases toward pain-related words or pictures. Of those, 2 found evidence of biases at subliminal presentation times, indicating vigilance (although 1 only after a stressful task). For supraliminal presentations, 1 study found evidence of avoidance, one of difficulty disengaging, and one of general slowing of responses. Only 1 study compared youth with and without pain for interpretation bias in adolescents, and interpretation biases were greater for youth with chronic pain. As with attention, no evidence for interpretation biases were found in youth without chronic pain. Overall, there is weak evidence to support vigilance in youth with chronic pain compared with those without. However, whether pain affects the subsequent deployment of attention is unclear. There is no evidence for biases toward pain in youth without chronic pain, but evidence suggests that anxiety or catastrophizing and attentional control may moderate pain-related attentional biases. There is also weak evidence of interpretation bias in youth with chronic pain compared with those without.

Efficacy of Heat Treatment of Factor VIII Concentrate

Two batches of heat-treated factor VIII concentrate were found to contain anti-HIV-positive plasma donations. The batches were dry-heat-treated at 68 degrees C for 2 and 24 h, respectively. No HIV seroconversions occurred in 13 susceptible haemophiliacs receiving a total of 540 bottles of these factor VIII preparations.     

Cytotoxic T lymphocyte precursor (CTL-p) frequency analysis in unrelated donor bone marrow transplantation: two case studies

HLA 'matched' unrelated donor bone marrow transplantation (BMT) is associated with an increased incidence and severity of acute graft-versus-host disease (GVHD) in comparison with HLA-identical sibling transplants. Using a limiting dilution analysis system for quantitating frequencies of alloreactive cytotoxic T lymphocyte precursors (CTL-p), we previously demonstrated a correlation between CTL-p frequency and HLA disparity between responder and stimulator, and between CTL-p frequency and the incidence of acute GVHD following HLA A, B, DR matched unrelated donor BMT. In this study we assayed CTL-p frequencies in two HLA 'matched' unrelated donor/patient pairs, with single HLA antigenic mismatches detected by allogenotyping or isoelectric focusing but not by HLA serology, and demonstrated that the CTL-ps were specifically directed at the mismatched antigen. Both class I and class II antigens were detected. These data, and our previous work, suggest that high CTL-p frequencies in HLA 'matched' unrelated pairs are indicative of HLA antigenic variants undetected by serology but recognized by molecular typing, and that these are responsible for the value of the assay in predicting acute GVHD after BMT. We propose that this assay system be used in aiding final donor selection before unrelated or mismatched related donor BMT.     

Identification of glycoprotein Ib as a target for autoantibody in idiopathic (autoimmune) thrombocytopenic purpura

An antibody (DIL) from a patient with idiopathic thrombocytopenic purpura (ITP) was shown to have autospecificity on the basis of reactions with autologous platelets that were identical to those obtained with platelets from normal subjects. DIL antibody also reacted strongly in an immunofluorescence test with platelets from a patient with Glanzmann's thrombasthenia, but failed to react with platelets from a patient with the Bernard-Soulier syndrome who was known to be deficient in glycoprotein Ib (GPIb). Purified GPIb and control platelets, but not Bernard-Soulier platelets, inhibited the lytic activity of DIL. Using the GPIb-specific monoclonal antibody AP1 and one-dimensional rocket electrophoresis into gels containing rabbit antihuman platelet membrane antibody, it was shown that staphylococcal protein A-Sepharose beads coated with DIL antibody selectively remove GPIb from solubilized platelet preparations. By crossed immunoelectrophoresis it was found that DIL recognizes a determinant on GPIb on the membrane side of the cleavage site of the platelet calcium- activated protease (calpain). These studies provide direct evidence for binding of a platelet autoantibody to a determinant on GPIb relatively close to the site of insertion of this protein into the platelet membrane.     

Reversion of the ELISPOT test after treatment in Gambian tuberculosis cases

Background  

New tools are required to improve tuberculosis (TB) diagnosis and treatment, including enhanced ability to compare new treatment strategies. The ELISPOT assay uses Mycobacterium tuberculosis-specific antigens to produce a precise quantitative readout of the immune response to pathogen. We hypothesized that TB patients in The Gambia would have reduced ELISPOT counts after successful treatment.     

Inter- and Intra-Subject Variability of Neuromagnetic Resting State Networks

Functional connectivity studies conducted at the group level using magnetoencephalography (MEG) suggest that resting state networks (RSNs) emerge from the large-scale envelope correlation structure within spontaneous oscillatory brain activity. However, little is known about the consistency of MEG RSNs at the individual level. This paper investigates the inter- and intra-subject variability of three MEG RSNs (sensorimotor, auditory and visual) using seed-based source space envelope correlation analysis applied to 5 min of resting state MEG data acquired from a 306-channel whole-scalp neuromagnetometer (Elekta Oy, Helsinki, Finland) and source projected with minimum norm estimation. The main finding is that these three MEG RSNs exhibit substantial variability at the single-subject level across and within individuals, which depends on the RSN type, but can be reduced after averaging over subjects or sessions. Over- and under-estimations of true RSNs variability are respectively obtained using template seeds, which are potentially mislocated due to inter-subject variations, and a seed optimization method minimizing variability. In particular, bounds on the minimal number of subjects or sessions required to obtain highly consistent between- or within-subject averages of MEG RSNs are derived. Furthermore, MEG RSN topography positively correlates with their mean connectivity at the inter-subject level. These results indicate that MEG RSNs associated with primary cortices can be robustly extracted from seed-based envelope correlation and adequate averaging. MEG thus appears to be a valid technique to compare RSNs across subjects or conditions, at least when using the current methods.