Pulmonary cytokine gene therapy. Adenoviral-mediated murine interferon gene transfer compartmentally activates alveolar macrophages and enhances bacterial clearance.
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Publications and source records attributed to S Nelson.
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This article covers the often overlooked area of team management concepts through a discussion of what many companies have done to implement these new concepts successfully. It describes the basics of how to and also explains why people resist the process of implementation. The main topics are (1) team formation, (2) pitfalls to avoid, and (3) team measurement.
The effects of acute ethanol intoxication on the functional activities of circulating and lung-recruited polymorphonuclear leukocytes (PMNs) and alveolar macrophages (AMs) were determined in rats challenged with intratracheal endotoxin to elucidate the mechanisms underlying the defects of pulmonary host defenses caused by acute ethanol intoxication. Acute ethanol Intoxication was induced by an intraperitoneal injection of 20% ethanol at a dose of 5.5 g of ethanol/kg. The control animals were injected with an equal amount of saline. Thirty min after intraperitoneal injection, rats were challenged with intratracheal endotoxin (300 micrograms/kg in 0.5 ml of saline) or saline. The rats were killed 3 h after intratracheal injection. CD11b/c expression on PMNs and phagocytosis and hydrogen peroxide generation of PMNs and AMs were determined by flow cytometry. Cytokine-Induced neutrophil chemoattractant (CINC) level in bronchoalveolar lavage fluid was measured with a specific ELISA. Intratracheal endotoxin caused a significant PMN recruitment into the lung in control animals. Acute ethanol intoxication completely suppressed the endotoxin-induced pulmonary recruitment of PMNs. Pulmonary-recruited PMNs exhibited a significant upregulation (8-fold) of CD11b/c expression when compared with circulating PMNs. This upregulation of CD11b/c expression was abolished by ethanol intoxication. Ethanol intoxication suppressed hydrogen peroxide generation by AMs and lung-recruited PMNs, and the phagocytosis of circulating PMNs. In contrast, acute ethanol intoxication did not affect pulmonary CINC production. These data indicate that the antiinflammatory effects of alcohol seem to be primarily based on the effects of ethanol on the PMNs themselves and not on the generation of certain chemotactic stimuli. In addition to the impairment of PMN recruitment, the suppression of AM and PMN activities also contributes to the mechanisms underlying ethanol-induced defects of pulmonary host defenses.
E1-deleted adenoviral vectors are efficient vectors for somatic cell gene therapy, but transgene expression is limited in part by a cytotoxic T cell response directed against virally transduced cells. Moreover, the development of a neutralizing antibody response limits secondary gene transfer with these vectors. Therapy with a depleting anti-CD4 antibody permits prolonged transgene expression in the lung and liver of mice. Furthermore, transient depletion of CD4+ lymphocytes blocks neutralizing antibody production and therefore allows repeat administration and expression of E1-deleted recombinant adenovirus. In this study, we investigated the efficacy of a novel nondepleting anti-CD4 antibody (RIB 5/2) in a model of lung-directed gene therapy in outbred rats. Treatment with RIB 5/2 permitted prolonged reporter gene expression and reduced adenovirus-induced peribronchial and alveolar inflammation in the lung. Moreover administration of RIB 5/2 blocked the development of an anti-adenoviral neutralizing antibody response in the lung and permitted secondary administration and expression of a recombinant adenovirus. These data support the role of immunomodulation in prolonging in vivo transgene expression by recombinant adenovirus.
The underlying brain injury that leads to autism has been difficult to identify. The diagnostic criteria of the disease are not readily associated with any brain region or system, nor are they mimicked by vascular accidents, tumors, or degenerative neurological diseases occurring in adults. Fortuitously, a recent report of autism induced by thalidomide exposure provides evidence that the disease originates by an injury at the time of closure of the neural tube. The human data suggest that the initiating lesion includes the motor cranial nerve nuclei. To test this hypothesis, we first examined motor nuclei in the brainstem of a human autistic case. The autopsy brain exhibited near-complete absence of the facial nucleus and superior olive along with shortening of the brainstem between the trapezoid body and the inferior olive. A similar deficit has been reported in Hoxa-1 gene knockout mice in which pattern formation of the hindbrain is disrupted during neurulation. Alternatively, exposure to antimitotic agents just after neural tube closure could produce the observed pattern of deficits. Thus, the lesions observed in the autopsy case appear to match those predicted by the thalidomide cases in both time of origin and central nervous system (CNS) location. To produce similar brain lesions experimentally, we exposed rat embryos to valproic acid, a second teratogen newly linked to autism. Dams received 350 mg/kg of valproic acid (VPA) on day 11.5 (the day of neural tube closure), day 12, or day 12.5 gestation. Each treatment significantly reduced the number of motor neurons counted in matched sections of the earliest-forming motor nuclei (V, XII), and progressively later exposures affected the VIth and IIIrd cranial nerve nuclei. All treatments spared the facial nucleus, which forms still later. Counts from the mesencephalic nucleus of trigeminal, the dorsal motor nucleus of the vagus, and the locus ceruleus were not affected by exposure to VPA, even though these nuclei form during the period when exposure occurred. Despite its effects on the motor nuclei, valproic acid exposure did not alter the further development of the brain in any obvious way. Treated animals were robust and had no external malformations. The autopsy data and experimental data from rats confirm that CNS injuries occurring during or just after neural tube closure can lead to a selective loss of neurons derived from the basal plate of the rhombencephalon. The results add two new lines of evidence that place the initiating injury for autism around the time of neural tube closure.
In this study we used a peroxidase model system (glucose/glucose oxidase and horseradish peroxidase) to investigate the effect of extracellularly generated reactive metabolites of 3,5-Me2-acetaminophen on cell viability and on cellular thiol levels. Incubation of hepatocytes with 3,5-Me2-acetaminophen in the presence of glucose/glucose oxidase and horseradish peroxidase caused a concentration-dependent loss of cell viability. Loss of viability was associated with decreased protein thiol levels. Addition of the reducing agent DTT, but not catalase, during the incubation restored cellular protein thiol levels and arrested the cell killing. Protein thiol depletion occurred selectively to the mitochondrial and microsomal fractions and was specific for a very limited number of protein bands. The data suggest that the oxidative modification of individual protein cysteine residues within the latter two organelle fractions is critically involved in the mechanism of toxicity.
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E1-deleted adenoviral vectors are increasingly being utilized for in vivo gene transfer. The potential use of these vectors is limited by transient expression of the transgene and a markedly reduced rate of transduction following readministration, presumably due to a host immune response to the vector. We hypothesized that CD4+ lymphocytes are necessary to generate an immune response to these vectors and that administration of a depleting anti-CD4 antibody (GK1.5) might prolong transgene expression in vivo. We found that pretreatment of mice with a single injection (transient depletion) or weekly injections of GK1.5 (persistent depletion), markedly prolonged expression of an adenovirus-encoded tumor necrosis factor (TNF) inhibitor or luciferase gene compared to controls. Moreover, mice treated with GK1.5 showed no antiadenoviral antibody response to repeat administration of the vector and a second adenoviral transgene could be expressed in these animals. However, control mice developed a significant neutralizing antibody response that prevented transgene expression with administration of a second adenovirus. These findings demonstrate that manipulation of the host immune response may expand potential applications of gene transfer utilizing adenoviral vectors.
Despite improved antimicrobials and advances in caring for critically ill patients, mortality from sepsis is still unacceptably high. Upregulation of the cellular immune system is one strategy for decreasing mortality in subjects with severe sepsis, which appears to be promising. Granulocyte colony stimulating factor (G-CSF) has been used successfully to decrease mortality in neutropenic subjects with sepsis. In this study, we have investigated whether pretreatment with G-CSF decreases mortality in non-neutropenic rodents with lethal Escherichia coli peritonitis. We implanted agar pellets impregnated with 5 x 10(8) cfu of Escherichia coli into the peritoneal cavities of rats pretreated with 50 micrograms/kg of G-CSF or an equal volume of 5% dextrose in water (D5W). Survival of these animals increased from 38 to 78% with G-CSF pretreatment. We also demonstrated an 11-fold increase in the number of polymorphonuclear leukocytes (PMNs) in animals treated with G-CSF. This increase in cells was seen initially only in the peripheral circulation. Twenty-four hours after induction of peritonitis, however, there was a three-fold greater increase in number of PMNs recovered from the peritoneal cavities of animals pretreated with G-CSF as compared to those treated with D5W. PMNs recovered from the peritoneal cavities of these animals had significantly elevated bactericidal activity (74% killing vs 53% killing) as compared to those cells recovered from the peritoneal cavities of control animals. These results indicate that G-CSF pretreatment improves survival of non-neutropenic animals with lethal Escherichia coli peritonitis by enhancing the cellular arm of the immune response.
OBJECTIVE: Our purpose was to compare the risk for preeclampsia and severe preeclampsia in triplet and twin gestations and to evaluate the effect of successful implantation on the development of preeclampsia and on perinatal outcome in triplet pregnancies conceived by means of in vitro fertilization. STUDY DESIGN: A case control study was conducted of triplet pregnancies (n = 38) matched for maternal age, parity, race, and delivery date with twin pregnancies (n = 38) resulting from a single fetal reduction (spontaneously or by means of multifetal pregnancy reduction) after successful implantation of triplets. All pregnancies were conceived by means of in vitro fertilization. Rates of preeclampsia and other maternal complications, factors affecting implantation, and perinatal outcomes were compared. Preeclampsia and severe preeclampsia were defined by The American College of Obstetricians and Gynecologists criteria. The Student t test and the chi(2) test were used for statistical analysis. RESULTS: The triplet group had a higher rate of severe preeclampsia (26.3%) than the twin (reduced triplet) group (7.9%). The prevalence of preeclampsia (mild and severe combined) also was higher among the triplet group (44.7%) than among the twin group (15.8%). There was no difference in other maternal complications of pregnancy or in factors potentially affecting implantation, such as assisted hatching. Mean fetal weight was lower among the triplet group, but gestational age at delivery was not significantly different. CONCLUSIONS: The rate of preeclampsia is higher among triplets conceived by means of in vitro fertilization than among triplets conceived by means of in vitro fertilization and reduced to twins. This finding suggests that fetal number, placental mass, or factors unrelated to the success of implantation are more important to the development of preeclampsia than is successful implantation alone.
Although antimicrobial therapy has been the central clinical strategy for patients with sepsis and multiple organ failure, the survival rate in these patients remains low because their host defense mechanisms usually are compromised. Various inflammatory cytokines recently have been shown to play important roles in normal host defense mechanisms and in sepsis and its sequelae. Cytokine modulation therapies, which have focused on the downregulation of the inflammatory response, have not been shown to benefit these patients. This article examines the role of granulocyte colony-stimulating factor as a proinflammatory mediator and a potential adjuvant treatment in patients with severe infection.
It is reported that some specific craniofacial characteristics are associated with obstructive sleep apnea syndrome (OSAS). To test this finding, the present study developed and assessed the feasibility of a craniofacial index score (CIS) in differentiating patients with OSAS from habitual snorers. Anthropometric measurements and lateral head radiographs were obtained on 24 male and 4 female patients with OSAS who had physician-diagnosed OSAS (respiratory disturbance index (RDI) >20), and 25 male and 5 female habitual snorers (RDI <20). Thirteen cephalometric and four anthropometric measure- ments were used in a discriminant model to construct the CIS. The model was able to correctly classify 82.1% of the OSAS group and 86.7% of the snoring group. In addition, variables that were related to the soft tissues, hyoid bone to mandibular plane, Body Mass Index, and soft palate length had the highest predictive value. These findings indicate that a CIS constructed from cephalometric and anthropometric measurements can be used to identify subjects with and without OSAS.
Clinical trials of new therapeutics for community-acquired pneumonia (CAP) have typically used a subjective endpoint of clinical response. However, as this endpoint is not quantitative, it is subject to observer bias and renders the conduct of multicenter trials difficult. For the purposes of conducting a clinical trial of filgrastim, as an adjunct to antibiotics for the treatment of CAP, a set of clinical criteria were developed prospectively to determine the time when a clinical cure was achieved, based on respiratory rate, temperature, oxygenation and roentgenographic findings, which was termed the time to resolution of morbidity (TRM). The TRM was evaluated on the first 100 patients entered in this clinical trial. As no clear reference standard exists, the predictive value for the duration of parenteral antibiotics (AB) and the length of hospital stay (LOS) was compared with that provided by a widely used classification system for severity of disease, APACHE II. The TRM was found to correlate significantly better with AB or LOS than APACHE II (P < 0.001). Furthermore, TRM offers the benefit over the endpoints of LOS and AB of being specifically designed to measure the patient's response to therapy, and, in fact, may aid physicians in determining the duration of parenteral antibiotic therapy. Hence, TRM is relevant to the clinician and is a useful tool to ensure uniformity in the assessment of the response to a new therapeutic in a multicenter clinical trial.
The purpose of this study was to describe the pattern of bony and soft tissue growth of the oropharynx in a sample of healthy, orthodontically untreated children. The sample consisted of 16 males and 16 females with lateral cephalograms at 6, 9, 12, 15, and 18 years of age, for a total of 160 lateral cephalometric radiographs. All subjects were enrolled in the Broadbent Bolton Study and their radiographs were used to produce the Bolton Standard Templates. Each radiograph was traced by hand and the tracings were paired and averaged to create a standard template for pharyngeal tissues at each age. In addition, all 160 tracings were digitized and means and standard deviations were calculated for 29 hard and 7 soft tissue measurements. Four linear (Ar-H,S-H,Go-H, Gn-H) and three angular (N-S-H, SN-ArH,GoGn-H) measurements demonstrated that the hyoid bone descends and moves slightly anteriorly up to age 18. The soft palate (PNS-P) increased 1 mm in length and 0.5 mm in thickness every 3 years after age 9. The distance between the anterior border of the atlas (ATA) and PNS did not change after age 12, while two soft tissue measurements (PNS-pharyngeal wall [PhW2] and posterior soft palate to pharyngeal wall [psp-PhW3]) increased. In general, two periods of accelerated change (6-9 years and 12-15 years) and two periods of quiescence (9-12 years and 15-18 years) were identified for the pharyngeal soft tissues. Further studies are needed to determine in soft tissues in the oropharynx continue to change after age 18.
OBJECTIVE: To investigate the effect of pretreatment with keratinocyte growth factor on acute permeability pulmonary edema. DESIGN: Prospective, randomized, controlled animal study. SETTING: University research laboratory. SUBJECTS: Specific pathogen-free Sprague-Dawley rats. INTERVENTION: Acute permeability pulmonary edema was induced with an injection of alpha-naphthylthiourea, and lung leak was assessed in an isolated perfused lung model over 180 mins. Leak was confirmed with wet/dry lung weight ratios, and the alveolar fluid protein concentration was measured after bronchoalveolar lavage. The effect of pretreatment with keratinocyte growth factor (injected intratracheally 48 hrs before the experiment) on alpha-naphthylthiourea-induced pulmonary edema was assessed (keratinocyte growth factor/alpha-naphthylthiourea group). Control groups (Control and keratinocyte growth factor/Control) were also studied. Histopathology was performed for each of the four groups. MEASUREMENTS AND MAIN RESULTS: The alpha-naphthylthiourea produced an acute permeability pulmonary edema detected by lung leak over the 180-min ex vivo period of monitoring the isolated perfused lung (leak = 8+/-mL; wet/dry weight ratio 14.7+/-2; lavage protein 3.1+/-1 mg/mL). Pretreatment with keratinocyte growth factor significantly attenuated these parameters (leak = 2.3+/-0.4 mL; wet/dry weight ratio 7.1 +/- 0.5; lavage protein 0.28 +/-0.03 mg/mL), which were not significantly different from the control group and the keratinocyte growth factor/control group. Histopathology showed abundant type II pneumocyte hyperplasia in the lungs of animals pretreated with keratinocyte growth factor, and marked pulmonary edema in animals pretreated with alpha-naphthylthiourea. Less edema was apparent in the keratinocyte growth factor/alpha-naphthylthiourea group. All data are expressed as mean +/- SEM. CONCLUSIONS: Pretreatment with keratinocyte growth factor significantly attenuates pulmonary edema induced by alpha-naphthylthiourea. The mechanisms of this protection are likely related to type II pneumocyte hyperplasia, but remain to be specifically elucidated.
We investigated the effect of alcohol (ethanol) on the ability of the alveolar macrophage to produce tumor necrosis factor-alpha (TNF-alpha), superoxide anion (O2-), and nitric oxide (NO)--three critical components of pulmonary host defense. Male rats were treated with alcohol either acutely (priming dose 175 mg/100 g of body weight, followed by a 7-hr continuous intravenous infusion of 30 mg/100 g of body weight/hr) or chronically (12-14 weeks of feeding ethanol in a liquid diet). Three hours before sacrifice, the rats received an intravenous injection of saline or lipopolysaccharide (LPS; Escherichia coli, 026:B6, 100 micrograms/100 g of body weight). Alveolar macrophages (AMs) were then isolated by bronchoalveolar lavage and assessed for their in vitro capacity to produce TNF-alpha, O2-, and NO spontaneously and in response to different stimuli. Acute alcohol administration suppressed in vitro LPS-stimulated AM TNF-alpha secretion by 52%. AMs from both pair-and alcohol-fed rats secreted TNF-alpha spontaneously in culture. However, the AMs from chronic alcohol-fed group secreted 42-53% less TNF-alpha spontaneously and in response to LPS, interferon-gamma (IFN-gamma) or IFN-gamma + LPS compared with the AMs from pair-fed group. Systemic LPS treatment inhibited in vitro LPS-stimulated AM TNF-alpha secretion (50%) only in the control rats. Acute alcohol administration enhanced significantly in vitro phorbol 12-myristate 13-acetate (PMA)- and opsonized zymosan (OPZ)-induced AM O2- secretion (4-and 1.8-fold, respectively). Systemic LPS treatment primed the AMs from control rats to secrete 83% more O2- in response to PMA but not OPZ; however, in the acute alcohol-treated group, it suppressed both PMA (54%)- and OPZ (66%)-induced AM O2- release (loss of priming effect of LPS). Chronic alcohol feeding suppressed PMA-induced AM O2- secretion (40%) without affecting the OPZ-induced release. Although systemic LPS treatment had no significant effect on PMA or OPZ-induced AM O2- secretion in the pair-fed group, it enhanced the PMA-stimulated AM O2- release (88%) in the alcohol-fed group. AMs recovered from control or acute alcohol-treated rats did not secrete NO spontaneously in vitro. However, AMs from both pair and chronic alcohol-fed rats secreted NO spontaneously with AMs from chronic alcohol-fed group secreting 34% less. Both acute and chronic alcohol treatment inhibited AM NO secretion in response to IFN-gamma, LPS, and IFN-gamma + LPS significantly. Systemic LPS had no effect on AM NO production in response to different in vitro stimuli in any of the treatment groups. These data suggest that (1) both acute and chronic alcohol administration to rats inhibit AM TNF-alpha and NO secretion; (2) acute and chronic alcohol treatment have differential effects on AM O2- secretion; and (3) alcohol-induced alteration in AM TNF-alpha, O2-, and NO secretion may in part explain the increased susceptibility of alcohol-consuming individuals to pulmonary infections.
The rate of glucose utilization (Rg) of various tissues including lung and bronchoalveolar lavage (BAL) fluids cells was measured, using the 2-deoxyglucose technique in Sprague-Dawley rats 4 h after challenge with either 1 mg/kg intravenous or 0.3 mg/kg intratracheal lipopolysaccharide (LPS). After intravenous LPS, Rg increased in whole lung and nonrespiratory tissues, but was unaltered in BAL cells. After intratracheal LPS, the Rg of nonrespiratory tissues was unchanged, but the Rg of BAL cells increased from 3.7 +/- 0.3 to 71.5 +/- 16.0 nmol/min. This increase in the Rg of BAL cells was explained by a doubling of the macrophage specific Rg, by a 100-fold increase in polymorphonuclear leukocytes (PMN) number, and by a higher Rg in PMN than in macrophages. These results demonstrate that increased glucose utilization after intratracheal LPS is confined to the respiratory system and that intra-alveolar phagocytes participate in this increase.