The identification of secreted heat shock 60 -like protein from rat glial cells and a human neuroblastoma cell line

The intracellular stress-induced proteins provide protection against toxic insults. Here, a 60,000-Da heat shock 60 (hsp60)-like protein was detected, with five different antibodies, in conditioned media derived from rat cortical astrocytes and a human neuroblastoma cell line. Extracellular neuroblastoma hsp60-like immunoreactivity was increased 3-fold in the presence of the neuropeptide vasoactive intestinal peptide (VIP) and was augmented 2-fold after temperature elevation. Intracellular hsp60 immunoreactivity was reduced 2-3-fold in the presence of VIP; this reduction was attenuated in the presence of brefeldin A, an inhibitor of protein secretion. In contrast, the activity of lactate dehydrogenase (LDH), an intracellular marker, did not change in the presence of VIP. Essentially no extracellular LDH activity was detected, indicating no cellular damage. A novel aspect for stress proteins having extracellular protective roles is suggested.

Oral tolerization to adenoviral proteins permits repeated adenovirus-mediated gene therapy in rats with pre-existing immunity to adenoviruses

Exposure to wild-type adenoviruses is common in humans and results in immune response against adenoviruses. The pre-existing antibodies and a strong secondary humoral and cellular immune response would interfere with gene transfer using recombinant adenoviral vectors. To test whether the secondary immune response can be abrogated by oral tolerization to adenoviral antigens, we immunized bilirubin-UDP-glucuronosyltransferase (BUGT)-deficient jaundiced Gunn rats with a recombinant adenovirus (5 x 10(9) pfu/rat) expressing the human UDP-glucouronosyltransferase (BUGT1) gene (Ad-hBUGT). Transgene expression was shown by reduction of mean serum bilirubin levels from 7.0 mg/dL to 2.3 mg/dL in 14 days, which then increased gradually to pretreatment levels in 6 weeks. All recipients developed antibodies (1:2[10]) and cytotoxic lymphocytes against the adenovirus. For oral tolerization, we administered to the immunized rats protein extracts of a recombinant adenovirus type 5 (1-1.5 mg/day) via duodenostomy tubes 10 to 40 days after the initial virus injection; control rats received bovine serum albumin. In rats fed adenoviral proteins and the BSA-fed controls, the antibody titers decreased to 1:2(7) and 1:2(9), respectively, in 70 days. Lymphocytes from the tolerized rats expressed TGF-beta1 upon exposure to antigen-presenting cells primed with adenoviral antigens, whereas IFN-gamma expression was undetectable. In contrast, lymphocytes from the BSA-treated control rats expressed IFN-gamma but not transforming growth factor beta1 (TGF-beta1). Seventy days after the first injection in the orally tolerized rats, but not in the controls, a second Ad-hBUGT injection caused human BUGT1 expression again, reducing serum bilirubin levels to those observed after the first injection. In the tolerized rats, serum antibody titers and anti-adenoviral cytotoxic lymphocyte activities continued to decline despite the second injection, whereas the antibody levels were boosted in the non-tolerized group. This results show that by preventing the secondary booster response, oral tolerization permits repeated adenovirus-directed gene transfer despite the presence of a residual antibody titer from a previous adenoviral exposure.

Cytokine gene therapy or infusion as treatment for solid human cancer

In the induction of tissue-directed immune responses, cytokines tend to be released within the affected tissues. We used two strategies to expose tumor tissues to continuous high levels of cytokines: First, a vaccinia interleukin (IL)2 recombinant was injected directly intratumorally 3-weekly at 10(7) pfus/dose in six patients with the solid tumor malignant mesothelioma (MM). No virus excretion was detectable. At each cycle vaccinia-IL-2 mRNA (SQ [semi-quantitative] reverse transcription polymerase chain reaction) was maximal 24-72 h following injection reduced at 8 days and faded by 21 days. No tumor regression occurred. Second, based on the success of granulocyte macrophage colony-stimulating factor (GM-CSF) in gene transfer experiments, we conducted a study using continuous intratumoral GM-CSF infusion in eight patients with MM using a portable pump at doses of 10 micro/cg/24 h over 8 weeks. Systemic neutrophil agglutination and local catheter-related difficulties occurred. Two patients demonstrated tumor necrosis, one of whom had a marked progressive mononuclear cell infiltration of the tumor associated with a partial response (>50% reduction in tumor area). Murine studies using our MM model in CBA and BALB/C mice have demonstrated that B7-1 and allo-class I transfections induce strong tumor-specific cytotoxic T lymphocyte responses: GM-CSF, IL-12, and IL-2 induced mixed nonspecific plus specific responses, whereas B7-2 and class II transfections were not effective. We conclude that increased intratumoral cytokine concentrations can be generated using both gene transfer and cytokine infusion approaches; however, both have their limitations and, at this stage, have not produced dramatic antitumor effects in humans.

Protection against developmental deficiencies by a lipophilic VIP analogue

Stearyl-Nle-VIP (SNV) is a novel agonist of vasoactive intestinal peptide (VIP) exhibiting a 100-fold greater potency than the parent molecule and specificity for a receptor associated with neuronal survival. Here, the developmental and protective effects of SNV were investigated in vivo using two models of developmental retardation, hypoxia and cholinergic blockade. In both cases chronic administration of SNV during development provided protective effects. Water maze experiments on the weaned animals have demonstrated a prophylactic action for SNV and enhancement of spatial memory in animals exposed to a cholinotoxin. SNV may act by providing neuroprotection, thereby improving cognitive functions. This work is dedicated to Prof. R.J. Wurtman whose inspiration and leadership in the field of neuroscience and cognition is beyond comparison.

Activity-dependent neurotrophic factor: structure-activity relationships of femtomolar-acting peptides

Activity-dependent neurotrophic factor (ADNF) is a glia-derived protein that is neuroprotective at femtomolar concentrations. A 14-amino acid peptide of ADNF (ADNF-14) has been reported that protects cultured neurons from multiple neurotoxins. Structure-activity relationships of peptides related to ADNF-14 now have been determined. A 9-amino acid core peptide (ADNF-9) has been identified that has greater potency and a broader effective concentration range (10(-16) to 10(-13) M) than ADNF or ADNF-14 in preventing cell death associated with tetrodotoxin treatment of cerebral cortical cultures. Deletions or conservative amino acid substitutions to ADNF-9 resulted in reduced potency, narrower effective concentration range and/or decreased efficacy. Removal of the N-terminal serine or the COOH-terminal isoleucine-proline-alanine from ADNF-9 produced a significant reduction in survival-promoting activity. Comparative studies of ADNF-9 action in mixed (glia plus neurons) vs. glia-depleted neuronal cultures indicated that ADNF-9 can act directly on neurons, although the potency of the peptide was 10,000-fold greater in mixed cultures. Kinetic studies showed that exposure to ADNF-9 for only 2 hr was sufficient to produce a 4-day protection against the cell-killing action of tetrodotoxin. Treatment with bafilomycin A1 (an inhibitor of receptor-mediated endocytosis) for 2 hr prevented the ADNF- and ADNF-9-mediated neuroprotection. ADNF-9, like ADNF-14, was neuroprotective against N-methyl-D-aspartate and the beta-amyloid peptide (amino acids 25-35), and had a much broader range of effective concentrations than ADNF-14. These studies identify ADNF-9 as an attractive lead compound for the development of therapeutic agents against neurodegenerative diseases.

Depressive symptoms and Norplant contraceptive implants

Women enrolled in a multicenter prospective study were evaluated to identify any possible relationship between depressive symptoms and the use of contraceptive implants. Women choosing Norplant implants (n = 910) were evaluated before starting this contraceptive and were reinterviewed at 6 months and 2 years. Women who continued the method had lower depressive symptom scores before initiating Norplant implants than did the women who discontinued the method or who were lost to follow up. Among the continuing Norplant implant users, the mean scores were similar before starting Norplant and at 6 months (7.9 vs 7.7). The strongest overall predictor of the depressive symptom score was relationship satisfaction. At 24 months, the subgroup of continuing users with decreased relationship satisfaction had an increase in depressive symptom score, but those with stable or improved relationships had stable depressive symptom scores. The subjects with the highest (i.e., worst) scores at enrollment demonstrated improved scores during follow-up. These results are reassuring for women who are concerned that Norplant use may adversely affect their mood.

Depressive symptoms and Depo-Provera

Women enrolled in a multicenter prospective study were evaluated to identify any possible relationship between depressive symptoms and the use of contraceptives. Women choosing Depo-Provera (n = 495) were evaluated before starting these contraceptives and were reinterviewed 1 year later. Women who continued the method had lower depressive symptom scores at baseline than did the women who discontinued the method or who were lost to follow-up. Among the continuing Depo-Provera users, the depressive symptom scores improved slightly at 1 year (7.4 vs 6.7). Those subjects with the highest (i.e., worst) scores at enrollment demonstrated improved scores at follow-up.

Cardiopulmonary interaction during partial liquid ventilation in surfactant-treated preterm lambs

Gas ventilation following instillation of perfluorochemical (PFC) liquid, partial liquid ventilation (PLV), improves gas exchange and pulmonary mechanics in neonatal animals and humans with severe respiratory distress. The effect of PLV on cardiac contractility, performance, pulmonary blood flow and ductal shunt has not been fully described. To this end, we evaluated these indices of cardiopulmonary function in eight conventionally gas ventilated, surfactant-treated premature lambs (125 days gestation) before and during PLV. Animals were instrumented with central venous and aortic lines. Serial evaluation of arterial blood chemistry/pressure, and pulmonary mechanics was performed; cardiac contractility, performance, pulmonary blood flow and ductal shunts were serially assessed by echocardiography. As compared to conventional gas ventilation, during PLV there was a significant decrease in left ventricular meridian (22.5+/-6.6 SE vs 8.1+/-1.4 SE g/cm2, P < 0.02) and circumferential wall stress (54.1+/-16.5 vs 24.4+/-3.8 SE g/cm2, P < 0.04) at end systole. The fall in wall stress at end systole was associated with a significant decrease in left ventricular internal diameter (1.2+/-0.05 SE vs 1.04+/-0.045 SE cm; P < 0.01). There were no significant changes in heart rate, systemic arterial and central venous pressures, systemic vascular resistance, left ventricular shortening and ejection fractions during PLV. The decrease in wall stress was associated with a significant decrease in mean airway pressures (15.9+/-1.1 SE vs 9.9+/-0.2 SE cmH2O; P < 0.05) and ostensibly a change in intrathoracic pressures during PLV. There were no significant differences in blood flows (pre vs during PLV; ml/min/kg): pulmonary (226+/-62 SE vs 293+/-65 SE), aortic (237+/-36 SE vs 204+/-21 SE), and left to right ductal (119+/-25 SE vs 105.5+/-26 SE) measured before and during PLV.

CONCLUSION

Cardiac output and pulmonary blood flow do not change significantly during PLV and therefore do not appear to contribute to improved gas exchange. This stable cardiac performance occurs at lower wall stress and thereby more advantageous energetic conditions.

Recurrence of symptoms in Clostridium difficile infection--relapse or reinfection?

We have fingerprinted Clostridium difficile isolates from patients with symptomatic recurrences of infection, using random amplified polymorphic DNA (RAPD). The medical records of 55/79 patients were examined, from whom multiple C. difficile-positive faeces were received during hospitalization at least five days, but no more than two months, apart. In 20 of these cases symptoms either did not recur (i.e., absent for at least three days between episodes), or were explainable by other causes, such as laxative administration. Of the remaining 35 patients, 27 sets of C. difficile isolates (23 pairs and four triplicates) were available for RAPD fingerprinting. Differing C. difficile DNA fingerprints (at least three major bands difference) were obtained for 15/27 patients, and hence at least 56% of the clinical recurrences of infection were in fact due to re-infection as opposed to relapse. Since we found that an endemic C. difficile clone was present in 18 out of 27 patients (67%) and accounted for 53% (31/58) of all isolates, it is probable that the majority of symptomatic recurrences are in fact re-infections, with either a different or the same C. difficile strain. We conclude that more attention must be given to preventing the re-infection of C. difficile symptomatic patients. Isolation of symptomatic individuals is the preferred option for the protection of other patients, but measures must be taken to ensure that further strain acquisition by the index cases does not occur.

Application of a Geographic Information System (GIS) To Characterisation Of Platypus (Ornithorhynchus anatinus) Habitat At Mount Emu Creek In Western Victoria

Platypuses appear to have an uneven distribution in Mt. Emu and Baillies Creeks. In the southern reaches of the creek near Skipton platypuses are abundant, whilst in a tributary near Lake Burrumbeet., I0 km to the north of Skipton, platypuses are rarely seen. A comparison of the creekside habitat at the two sites was made and differences in river form, vegetation cover and adjacent land use were identified. All site and platypus data were downloaded into the GIS software mapping package Map info and stored in table format but were accessible through use of the information tool. A digital camera was used to provide supplementary photographic information of creekside conditions. The digital photographs were incorporated directly into the mapwork, facilitating visualisation of the local conditions. Radio tracking showed burrow sites used by platypuses. These were characterised and all data entered into Map info. An attempt has been made to include in the mapwork the relative intensity of use platypuses make of different areas within their home ranges. Expansion of this database with further work and knowledge of platypus requirements should eventually lead to an attempt at predictive mapping of the presence of platypuses in the region.

Geographic analysis of pertussis infection in an urban area: a tool for health services planning

OBJECTIVE

This study examined whether incident cases of pertussis cluster in urban census tracts and identified community characteristics that predict high-incidence areas.

METHODS

An ecological study design was used. The study population included all persons diagnosed with pertussis from January 1, 1986, through December 31, 1994. Maps of rates were constructed via a geographic information system and clustering was statistically confirmed. Associations between pertussis rates and community characteristics were tested.

RESULTS

Mapping and statistical analysis revealed spatial clustering of pertussis. Higher age-adjusted rates of pertussis infection were associated with higher proportions of residents below poverty level.

CONCLUSIONS

In urban areas pertussis infection clusters in areas of poverty.

Lupus-specific antibodies reveal an altered pattern of somatic mutation

The F4 idiotype is a heavy chain determinant expressed almost exclusively on IgG immunoglobulins and is highly associated with specificity for double-stranded DNA. Since high-titered F4 expression is present predominantly in sera of patients with systemic lupus erythematosus (SLE), we thought F4+ IgG antibodies might constitute a useful subset of immunoglobulins in which to investigate lupus-specific alterations in variable (V) region gene expression or in the process of somatic mutation. This molecular analysis of F4+ B cell lines generated from lupus patients demonstrates that despite the strong association of F4 reactivity with specificity for native DNA, there is no apparent VH gene restriction. Furthermore, VH gene segments encoding these antibodies are also used in protective immune responses. An examination of the process of somatic mutation in F4+ antibodies showed no abnormality in frequency of somatic mutation nor in the distribution of mutations in complementarity-determining regions or framework regions. However, there was a decrease in targeting of mutations to putative mutational hot spots. This subtle difference in mutations present in these antibodies may reflect an intrinsic defect in mutational machinery or, more likely, altered state of B cell activation that affects the mutational process and perhaps also negative selection.

Mechanisms of intrathymic tolerance induction to isolated rat hepatocyte allografts

Intrathymic injection of alloantigen in young adult rats is capable of mediating long-lived transplantation tolerance. In this study, we use a well-defined model of isolated hepatocyte transplantation to define the mechanisms of intrathymic induced tolerance. The recipient rats are Nagase analbuminemic rats (NAR) that are deficient in albumin, to allow for following transplant acceptance using metabolic and genetic markers. Tolerance to allogeneic hepatocyte transplants could be mediated by intrathymic injection of live allogeneic splenocytes, lethally irradiated splenocytes, or isolated hepatocytes. Intrathymic injection of live allogeneic splenocytes, but not of hepatocytes or irradiated splenocytes, resulted in donor microchimerism in peripheral lymphoid organs, with preferential expansion of CD4-positive T cells in the recipient spleens. Tolerance could be adoptively transferred from tolerant animals to naive recipients, but only from those animals that had been inoculated with intrathymic donor splenocytes. We conclude that donor microchimerism is found after intrathymic inoculation of live splenocytes, but is not required for tolerance induction and that microchimerism is not an absolute requirement for the generation of regulatory cells.

S-nitrosohemoglobin in the fetal circulation may represent a cycle for blood pressure regulation

It has recently been demonstrated, in rats, that hemoglobin transports nitric oxide (NO), as S-nitrosocysteine, from the lungs to the peripheral tissues. This cycle may be involved in the regulation of blood pressure and efficient delivery of oxygen in adult animals. We sought to determine whether this model was applicable to the human fetus. Umbilical cord blood was obtained from deliveries between 37 and 42 weeks of gestation (n = 19). NO, released from erythrocyte s-nitrosohemoglobin (SNO-Hb), was determined by the Saville reaction and total plasma NO was determined by the Greiss reaction. SNO-Hb levels were found to be higher in the umbilical vein, [SNO]/[Hb] = 2.19 +/- 1.22 (X10(-3)), than in the artery, [SNO]/[Hb] = 1.45 +/- 0.66 (X10(-3)) (P < 0.001, Wilcoxon Signed Rank test). This supports the hypothesis that fetal blood pressure may be regulated by erythrocytes acting via a hemoglobin-based mechanism.

Phase II study of 21 day schedule oral etoposide in children. New Agents Group of the United Kingdom Children's Cancer Study Group (UKCCSG)

We report a multicentre phase II study of orally administered prolonged schedule etoposide in children with refractory or relapsed malignancy. 83 children were entered into the study. The largest diagnostic groups were neuroblastoma (n = 20), rhabdomyosarcoma/soft tissue sarcoma (n = 16) and brain tumours (n = 16). Etoposide was administered twice daily at a dose of 50 mg/m2/day for 21 days using the intravenous preparation given orally. Disease reassessment was performed after the second course. Etoposide plasma concentrations were measured by HPLC, 2 and 6 h after administration of therapy on days 7 and 14 in 15 patients. 61 patients completed two courses and were evaluable for response. There was 1 complete response (CR), 5 partial responses (PR) 22 stable disease (SD) and 33 progressive disease (PD). Of the 6 with responses, 3 had a diagnosis of medulloblastoma/cerebral primitive neuroectodermal tumour. 24 of 26 patients with SD/PR/CR received further courses with excellent palliative effect. The main toxicity observed was myelosuppression, with 8% and 7% of evaluable courses complicated by grade III-IV neutropenia and thrombocytopenia, respectively. Severe infection (grade III-IV) was rare, complicating only 2/94 evaluable courses. Plasma etoposide median concentrations at 2 h after administration on day 7 of course 1 were 1.5 (range 0.6-2.4) micrograms/ml. Total course 1 area under the etoposide plasma concentration versus time curve (AUC) values were estimated using a limited sampling model. Grade > or = 2 leucopenia was only observed in patients with a day 72 h etoposide concentration of > 2 micrograms/ml or a course 1 AUC of > 35 mg/ml.min. It is concluded that given at a dose of 50 mg/m2/day in two doses for 21 day courses, oral etoposide is well tolerated in children. A correlation between drug concentrations and toxicity was observed. Overall, a low response rate was seen (approximately 10%), but disease stabilisation appears to occur, and useful palliative effect was frequently noted. The response in brain tumours was more encouraging (3/14 PR) and this group requires further evaluation.

Transient immunosuppression with FK506 permits long-term expression of therapeutic genes introduced into the liver using recombinant adenoviruses in the rat

The host immune response limits the duration of expression of adenovirally transduced genes and precludes long-term gene expression upon re-administration of the virus. In this study we wished to evaluate whether short-term immunosuppression of the host, at the time of recombinant virus administration, would allow expression of the therapeutic gene product upon virus reinjection. Gunn rats were used as recipients of recombinant adenoviruses expressing human BUGT (Ad-hBUGT) or E. coli beta-galactosidase (Ad-LacZ). Rats were treated with FK506 (1-1.5 mg/kg, per OS daily) for three days beginning 24 hours before each virus injection. Control groups did not receive any immunosuppressant. The serum bilirubin level was reduced from 7.1 +/- 0.75 mg/dL to 2.0 +/- 0.7 mg/dL within two days of viral injection in both FK506 treated and control groups, and then gradually increased in 6 weeks. FK506-treated rats had low or undetectable antibody titers against the recombinant adenovirus and minimal or no cytotoxic T lymphocyte (CTL) response against adenovirus-infected cells. The tolerized rats received two subsequent injections 42 and 98 days after the first injection, which reduced the bilirubin levels again to 2.0 +/- 0.56 and 2.2 +/- 0.61 mg/dL, respectively. In contrast, control rats developed high titer neutralizing antibodies and a CTL response, and their serum bilirubin levels were not reduced following subsequent injections. We conclude that short-term FK506 treatment around the time of virus administration prevents the host immune response, permitting long-term gene therapy by repeated administration of the recombinant virus.

Protection against developmental retardation in apolipoprotein E-deficient mice by a fatty neuropeptide: implications for early treatment of Alzheimer's disease

Stearyl-Nle17-VIP (SNV) is a novel agonist of vasoactive intestinal peptide (VIP) exhibiting a 100-fold greater potency than the parent molecule and specificity for a receptor associated with neuronal survival. Here, mice deficient in apolipoprotein E (ApoE), a molecule associated with the etiology of Alzheimer's disease, served as a model to investigate the developmental and protective effects of SNV. In comparison to control animals, the deficient mice exhibited (a) reduced amounts of VIP messenger RNA; (b) decreased cholinergic activity (c) significant retardation in the acquisition of developmental milestones: forelimb placing behavior and cliff avoidance behavior; and (d) learning and memory impairments. Daily injections of SNV to ApoE-deficient newborn pups resulted in increased cholinergic activity and marked improvements in the time of acquisition of behavioral milestones, with peptide-treated animals developing as fast as control animals and exhibiting improved cognitive functions after cessation of peptide treatment. Specificity was demonstrated in that treatment with a related peptide (PACAP), pituitary adenylate cyclase-activating peptide, produced only limited amelioration. As certain genotypes of ApoE increase the probability of Alzheimer's disease, early counseling and preventive treatments may now offer an important route for therapeutics design.

Moclobemide in social phobia: a controlled dose-response trial

Although the monoamine oxidase inhibitor phenelzine has proven efficacious in social phobia, the risk of hypertensive crises has reduced its acceptability. The reversible monoamine oxidase inhibitor moclobemide has less potential for such reactions, but its efficacy in this disorder remains unproven. A double-blind, placebo-controlled study was undertaken to assess the efficacy and safety of fixed doses of moclobemide. After a 1-week placebo run-in, subjects with social phobia were randomly assigned to placebo or one of five doses (75 mg, 150 mg, 300 mg, 600 mg, or 900 mg daily) of moclobemide for 12 weeks. Although a trend toward greater efficacy of higher doses of moclobemide was observed at 8 weeks, no differences in response to various doses of the drug and placebo were observed at 12 weeks. At 12 weeks, 35% of subjects on 900 mg of moclobemide and 33% of those on placebo were at least much improved. Moclobemide was well tolerated, insomnia being the only dose-related adverse event observed with the drug. In this dose-response trial, moclobemide did not demonstrate efficacy at 12 weeks. Some other controlled studies have found moclobemide and brofaromine, another reversible monoamine oxidase inhibitor, efficacious in social phobia. Possible reasons for inconsistent findings are discussed.

Preferential sequestration in vitro of BCR/ABL negative hematopoietic progenitor cells among cytokine nonresponsive CML marrow CD34+ cells

It is believed that long-term cultures of CML marrow cells favor the outgrowth of BCR/ABL negative hematopoietic progenitor cells (HPC) and that this phenomenon may be enhanced with negative hematopoietic regulators which can maintain primitive HPC in a quiescent state. Proliferation of CML marrow CD34+ cells in primary short-term cultures, maintained in the presence or absence of macrophage inhibitory protein-1 alpha (MIP-1 alpha), was tracked with the membrane dye PKH2. After 7 to 10 days it was possible to distinguish between cytokine responsive (CR) CD34+ cells (cells which had divided thus becoming PKH2dim) and cytokine nonresponsive (CNR) CD34+ cells (cells which had not divided and had therefore remained PKH2bright). CR and CNR CD34+ cells were isolated by flow cytometric cell sorting, seeded in secondary long-term cultures, and their progeny cells assayed weekly for their clonogenic progenitor cell content and expression of BCR/ABL by reverse transcriptase polymerase chain reaction (RT-PCR). Whereas CNR cells isolated from control primary cultures (control/CNR) sustained in vitro hematopoiesis, similar cells from cultures treated with MIP-1 alpha (MIP-1 alpha/CNR) supported a higher and, in some patients, a more extended production of clonogenic HPC, indicating that MIP-1 alpha was able to maintain primitive HPC in a quiescent state. Predominance of BCR/ABL negative progenitors in vitro was more evident in secondary cultures initiated with CNR cells than in those initiated with CR cells, especially those established with MIP-1 alpha/CNR cells. Of interest is the observed decline in the percentage of BCR/ABL+ progenitors in these cultures with time. Whereas up to 100% of progenitors were BCR/ABL+ on day 0, by day 14, only 46% of progenitors in MIP-1 alpha/CNR secondary cultures were BCR/ABL+ and by day 28 and beyond, the percentage of BCR/ABL+ progenitors dropped to below 20%. These results suggest that the quiescent nature of normal HPC present in CML marrow may favor their identification via cell tracking and, subsequently, their isolation from the more actively cycling leukemic cells. These studies also confirm the feasibility of employing negative hematopoietic regulators to augment the sequestration of normal HPC among the cytokine nonresponsive fraction of CD34+ cells, an approach that may be clinically feasible for autotransplantation.

Antiserum to activity-dependent neurotrophic factor produces neuronal cell death in CNS cultures: immunological and biological specificity

Activity-dependent neurotrophic factor (ADNF) is a glia-derived protein that is neuroprotective at femtomolar concentrations. ADNF is released from astroglia after treatment with 0.1 nM vasoactive intestinal peptide (VIP). To further assess the biological role of ADNF, antiserum was produced following sequential injections of purified ADNF into mice. Anti-ADNF ascites fluid (1:10,000) decreased neuronal survival by 45-55% in comparison to untreated cultures or those treated with control ascites. The neuronal death after anti-ADNF treatment was observed in cultures derived from the spinal cord, hippocampus or cerebral cortex at similar IC50's. Using a terminal deoxynucleotidyl transferase in situ assay to estimate apoptosis in cerebral cortical cultures, anti-ADNF was shown to produce a 70% increase in the number of labeled cells in comparison to controls. In spinal cord cultures, anti-ADNF treatment produced a 20% decrease in choline acetyltransferase activity in comparison to controls. Neuronal cell death produced by the antiserum to ADNF was prevented in cultures co-treated with purified ADNF or ADNF-15, an active peptide derived from the parent ADNF. In vitro binding between the anti-ADNF and ADNF-15 was demonstrated with size exclusion chromatography. Comparative studies with other growth factors (insulin-like growth factor-1, platelet-derived growth factor, nerve growth factor, epidermal growth factor, ciliary neurotrophic growth factor, and neurotrophin-3) demonstrated that only ADNF prevented neuronal cell death associated with electrical blockade. These investigations indicated that an ADNF-like substance was present in cultures derived from multiple locations in the central nervous system and that ADNF-15 exhibited both neuroprotection and immunogenicity. ADNF appears to be both a regulator of activity-dependent neuronal survival and a neuroprotectant.

Prenatal diagnosis of the 22q11 deletion syndrome

A 27 weeks gestation fetus, evaluated because of polyhydramnios, was found by echocardiography to have an interrupted aortic arch type B. Because of the known association between this malformation and DiGeorge syndrome, an amniocentesis was performed. Fluorescence in situ hybridization revealed a 22q11 deletion. This is, to our knowledge, the first report of prenatal detection of a fetus with 22q11 deletion in the absence of a family history.

Insertion of the adenoviral E3 region into a recombinant viral vector prevents antiviral humoral and cellular immune responses and permits long-term gene expression

Recombinant adenoviruses (Ads) are highly efficient at transferring foreign genes to the liver in vivo; however, the duration of gene expression is limited by the host antiviral immune response, which prevents expression upon readministration of the virus. To test whether overexpression of the immunomodulatory products of the early Ad genome region 3 (E3) could prevent the antiviral immune response and prolong expression of foreign genes delivered by Ad vectors, we injected a recombinant Ad (Ad-E3-hBUGT), containing both E3 and the human bilirubin-uridine-diphosphoglucuronate-glucuronosyltransferase (BUGT) genes, into BUGT-deficient hyperbilirubinemic Gunn rats. Control Gunn rats received Ad-hBUGT, which expresses human BUGT alone. An initial injection of either virus resulted in hepatic expression of human BUGT as evidenced by excretion of bilirubin glucuronides in bile and a reduction of mean serum bilirubin levels from 7.0 mg/dl to 1.9-2.7 mg/dl within 7 days. In Ad-E3-hBUGT-injected rats, serum bilirubin levels increased to 4.5 mg/dl by 84 days after infection, but a second administration of the virus on that day resulted in a hypobilirubinemic response similar to that seen with the first injection. In contrast, rats receiving Ad-hBUGT had serum bilirubin levels of 7 mg/dl on day 84 after infection, but showed no reduction of serum bilirubin by reinjection of the virus on that day. In the rats injected with Ad-E3-hBUGT, but not in the ones injected with Ad-hBUGT, there was a marked inhibition of the antiviral antibody and Ad-specific cytotoxic T lymphocyte responses. This is the first demonstration that insertion of E3 genes in recombinant Ads facilitates readministration of a functional vector for long-term correction of an inherited metabolic disorder.

Oral tolerization to adenoviral antigens permits long-term gene expression using recombinant adenoviral vectors

Recombinant adenoviruses (Ads) efficiently transfer foreign genes into hepatocytes in vivo, but the duration of transgene expression is limited by the host immune response which precludes gene expression upon readministration of the virus. To test if this immune response can be abrogated by oral tolerization, we instilled protein extracts of a recombinant adenovirus type-5 via gastroduodenostomy tubes into bilirubin-UDP-glucuronosyltransferase-1 (BUGT1)-deficient jaundiced Gunn rats. Control rats received BSA. Subsequent intravenous injection 5 x 10(9) pfu of a recombinant adenovirus-expressing human BUGT1 (Ad-hBUGT1) resulted in hepatic expression of human BUGT1 (hBUGT1) with reduction of serum bilirubin levels by 70%. After 2 mo serum bilirubin increased gradually. In orally tolerized rats, but not in controls, a second dose of the virus on day 98 markedly reduced serum bilirubin again. In the tolerized rats, the development of antiadenoviral neutralizing antibodies and cytotoxic lymphocytes were markedly inhibited, and transplantation of their splenocytes into naive Gunn rats adoptively transferred the tolerance, indicating a role for regulatory cells. Lymphocytes from the tolerized rats hyperexpressed TGFbeta1, IL2, and IL4 upon exposure to viral antigens, whereas IFNgamma expression became undetectable. Thus, oral tolerization with adenoviral antigens permits long-term gene expression by repeated injections of recombinant adenoviruses.

The effectiveness of a needleless intravenous connection system: an assessment by injury rate and user satisfaction

OBJECTIVE

To assess the impact of a needleless intravenous (i.v.) connection system on the rate of reported intravenous-connection-related (IVCR) percutaneous injuries, and to assess user satisfaction, frequency of use, and barriers to use.

DESIGN

A pre-post intervention design, with injury incidence rates being compared 3 years before and 1 year after hospital wide device implementation; and a cross-sectional descriptive user satisfaction survey.

SETTING

Two tertiary-care teaching hospitals, one general and one pediatric, located in a large metropolitan medical center.

OUTCOME VARIABLE

All IVCR percutaneous injuries reported to the employee health services at both hospitals during the years from 1989 to 1991 and 1993.

STUDY POPULATION

Survey participants were selected randomly from licensed nursing employees at both hospitals.

INTERVENTION

i.v. connection system consisting of blunt plastic cannulas and compressed latex injection sites.

RESULTS

After device implementation, the IVCR injury rate was reduced 62.4% (rate ratio [RR], 0.38; 95% confidence interval [CI95], 0.27-0.53) at the general hospital and 70.2% (RR, 0.30; CI95, 0.17-0.53) at the pediatric hospital. After adjusting for the reduction in injury rate due to factors other than device implementation, the IVCR injury rate was reduced 54.5% (adjusted RR, 0.46; CI95, 0.32-0.65) at the general hospital and 57.2% (adjusted RR, 0.43; CI95, 0.24-0.78) at the pediatric hospital. Approximately 94% of survey respondents (n = 478, response rate = 51%) were satisfied with the device and recommended continued use. However, needles still were being used for activities that could have been performed with the needleless system because of compatibility, accessibility, and other technical problems related to the device.

CONCLUSIONS

The device was effective in reducing the rate of reported IVCR percutaneous injuries and users were satisfied with the device, but barriers to universal use were identified.

Comparison of the efficacy of paracetamol versus paracetamol, codeine and promethazine (Painstop) for premedication and analgesia for myringotomy in children

This prospective double-blinded study compared the analgesic effectiveness and incidence of complications of a compound preparation Painstop (Paedpharm Pty Ltd) containing paracetamol 12 mg, codeine 0.5 mg and promethazine 0.65 mg per 1.0 ml, dosage 1.0 ml/kg, with paracetamol 20 mg/kg. Ninety-five children aged 1 to 12 years, ASA 1-2, scheduled for myringotomy and drain tuber insertion as a day procedure were randomized to receive Painstop or paracetamol 30 to 60 minutes prior to surgery. Preoperative drowsiness and complications on induction and postoperative sedation, pain and times to achieve goals were recorded. The groups were comparable for age, gender, weight, anaesthetic technique and duration of surgery. Times to eye opening (P = 0.05) and first oral intake (P = 0.006) were significantly longer in the Painstop group. There was, however, no difference in times to discharge. Late sedation was more common in the Painstop group (P = 0.03). Pain scores were low and similar in both groups and the need for additional analgesia was uncommon.

Induction of central tolerance by intrathymic inoculation of adenoviral antigens into the host thymus permits long-term gene therapy in Gunn rats

Recombinant adenoviruses are highly efficient at transferring foreign genes in vivo. However, duration of gene expression is limited by the host antiviral immune response which precludes expression upon viral readministration. We tested the feasibility of prolonging gene expression by induction of central tolerance to adenoviral antigens in bilirubin-UDP-glucuronosyltransferase-1 (BUGT1)-deficient Gunn rats. Tolerance was induced by intraperitoneal injection of antilymphocyte serum, followed by intrathymic inoculation of one of the following: a recombinant adenovirus (Ad), adenovirus human UDP-glucuronosyltransferase (Ad-hBUGT1) carrying the hBUGT1 gene; a protein extract of the same virus; or viral infected hepatocytes. Controls received intrathymic injections of normal saline. After 12 d all groups were injected intravenously with 5 x 10(9) pfu of either Ad-hBUGT1 or adenovirus beta-galactosidase (Ad-LacZ) (expressing the Escherichia coli beta-galactosidase [LacZ] gene). In all three groups of tolerized rats, hBUGT1 was expressed in the liver after administration of Ad-hBUGT1, with glucuronidation of biliary bilirubin of above 95%. Serum bilirubin levels decreased from 7.2 to 1.8 mg/dl within 1 wk and remained low for 7 wk. Similar findings were observed following repeat injections given on days 45 and 112. In control rats serum bilirubin levels were reduced for only 4 wk, and viral readministration was ineffective. In all tolerized groups, but not in controls, there was a marked inhibition of appearance of neutralizing antibodies and cytotoxic lymphocytes against the recombinant adenovirus. Injection of wild type adenovirus-5 (Ad5) into the tolerized rats elicited a wild type-specific cytotoxic lymphocyte response. This is the first demonstration of Ad-directed long-term correction of an inherited metabolic disease following central tolerization with thymic antigen.

An in vitro assay for detection of glomerular binding IgG autoantibodies in patients with systemic lupus erythematosus

The deposition of anti-dsDNA antibodies in the glomerulus is believed to play a critical role in the pathogenesis of nephritis in SLE. However, an absolute correlation between serum levels of anti-dsDNA antibodies and renal disease has not been found. Recently a glomerular binding assay (GBA) has been developed to detect IgG binding to isolated rat glomeruli. We have used the GBA to study sera from four groups of SLE patients: (A) + anti-dsDNA antibodies, active nephritis; (B) - anti-dsDNA antibodies, active nephritis; (C) + anti-dsDNA antibodies, no nephritis; and (D) - anti-dsDNA antibodies, no nephritis. The serum anti-dsDNA antibodies in group A and group C patients could not be distinguished on the basis of isotype, charge, or cross-reactivity with histones. Nevertheless, the mean intensity of glomerular immunofluorescence was significantly higher in group A than in the three other patient groups and distinguished between patients with serum anti-dsDNA antibodies who had nephritis and those without clinically apparent nephritis. GBA reactivity was unaffected by DNase treatment of sera, but was partially inhibited by preincubation with dsDNA. These findings are consistent with the hypothesis that some anti-dsDNA antibodies cross-react with glomerular components and that the presence of this cross-reactivity is associated with, and may be responsible for, the development of nephritis. In addition, we have identified a group of SLE patients with renal disease and typical renal histopathology and immune deposits who do not have serum anti-dsDNA antibodies or antibodies that directly bind to glomeruli in the GBA. The mechanism of renal immune deposition in these patients remains to be determined.

HLA-DRB1 and DQB typing of Hispanic American patients with rheumatoid arthritis: the "shared epitope" hypothesis may not apply

OBJECTIVE

To determine whether the association of particular MHC class II alleles and the DRB1 "shared epitope" with disease susceptibility and severity in rheumatoid arthritis (RA) applies to ethnic groups other than Caucasian Americans.

METHODS

67 Hispanic American patients with RA and a similar number of ethnically matched controls were typed for DRB1 using polymerase chain reaction methods. DR4 subtype and DQB1 type were determined for the subjects positive for DR4. Disease severity in the patients with RA was assessed by clinical, radiographic and laboratory variables.

RESULTS

The frequency of DR4 was significantly increased in the subjects with RA compared to the control group. However, the "shared" DRB1 amino acid sequence was relatively infrequent in the Hispanic American patients with RA, and there was no association of specific DR4 or DQ alleles with more severe disease or extraarticular manifestations.

CONCLUSION

The HLA markers that predict poor prognosis and suggest that more aggressive clinical management may be appropriate in Caucasian American patients with RA may not be useful in other ethnic groups.

Retroviral gene transfer in autologous bone marrow transplantation for adult acute leukemia

To evaluate whether marrow contributes to relapse after autologous bone marrow transplantation (AuBMT) for acute leukemia, transplanted marrow was marked with the G1N retroviral vector (Genetic Therapy Inc.) containing the neomycin phosphotransferase gene (neo). Between April 1992 and August 1993, 4 patients were transplanted for acute myeloid leukemia (AML) in second complete remission (CR) and 1 patient for acute lymphoid leukemia in first CR. An average of 12.4% (range 5-19%) of transplanted marrow mononuclear cells were exposed to G1N vector for 4 hr. In the vector-treated portion of the marrow, 4.9% of GM-CFU and 3.6% of erythroid burst-forming units (BFU-E) were resistant to G418 in vitro. In the 5 patients, the polymerase chain reaction (PCR) detected the neo sequence on only two occasions after AuBMT. Of 4 patients surviving 1 year after transplantation, only 1 had evidence of gene marked cells by PCR. Two AML patients have relapsed, one of whom had evidence of neo sequences in the bone marrow at day 100 but not at relapse 11 months after AuBMT. The second patient relapsed 18 months after AuBMT but never had PCR evidence of neo sequences before or after relapse. Our results indicate vector-transduced autologous bone marrow from heavily pretreated adults with acute leukemia mark with low efficiency, although vector sequences have been detected in bone marrow and peripheral blood up to 1 year after transplant. Of the 2 relapsed patients, no evidence of vector-marked leukemic blasts have been detected.

Lymphocytosis of donor origin in cerebrospinal fluid, and marrow aplasia after donor leukocyte infusion for EBV-lymphoproliferative disease

A 29-year-old woman underwent a T cell-depleted unrelated donor transplant for CML in chronic phase. Sixty-three days after marrow infusion, the patient developed fevers and generalized lymphadenopathy. Lymph node biopsy was consistent with monoclonal EBV-associated immunoblastic lymphoma for which the patient received 10(5) CD3-positive donor leukocytes per kilogram. Six days after leukocyte infusion the patient developed mental status changes without focal neurological deficit. MRI revealed no mass lesions. Cerebral spinal fluid revealed a white blood cell count of 1650 cells/mm3 which were shown to be T lymphocytes of donor origin. The CSF was tested and found to be PCR positive for EBV virus interval repeat 1 sequence (IR1). The lymphocytosis and mental status changes resolved without specific intervention. Subsequently she developed marrow aplasia, which was believed to be secondary to the infusion of donor leukocytes. Possible mechanisms for these two previously unreported side-effects of donor leukocyte infusion are discussed.

Forced over-expression of the myeloid zinc finger gene MZF-1 inhibits apoptosis and promotes oncogenesis in interleukin-3-dependent FDCP.1 cells

The myeloid zinc finger protein MZF-1 is important in hematopoiesis. Previous studies have found that reducing expression of MZF-1 inhibited G-CSF-driven human marrow colony formation assays. In this study we found that retrovirally overexpressing MZF-1 in IL-3-dependent FDCP.1 cells inhibited their apoptosis when IL-3 was withdrawn. The MZF-1-transduced FDCP.1 cells also formed tumors when injected into congenic mice, whereas control FDCP.1 cells did not.

Regulation of VIP gene expression in general. Human lung cancer cells in particular

Vasoactive intestinal peptide (VIP) is a neuropeptide of multiple functions affecting development and aging. In cancer, for example, VIP was found to function as an autocrine growth factor in nonsmall cell lung cancer (NSCLC) promotion. Furthermore, a VIP hybrid antagonist (neurotensin(6-11)-VIP(7-28)) was found to inhibit NSCLC growth. In the present study, the expression of VIP mRNA was studied using human lung cancer cells. RNA prepared from 19 cell lines was fractionated by 1% agarose gel electrophoresis followed by blotting onto nitrocellulose membranes and hybridization to a VIP-specific RNA probe. VIP mRNA was detected in about 50% of the cell lines tested with a greater abundance in NSCLC. Cultures of the NSCLC NCI-H727 cell line were treated with forskolin, an activator of cyclic AMP (cAMP), and separately with the tumor promoter phorbol 12-myristate 13-acetate (PMA). Northern blot hybridization analysis showed an increase in VIP mRNA levels after 4 h treatment with 50 microM forskolin. Incubation with PMA also showed a significant increase in the levels of VIP transcripts. Cultures were then incubated with PMA in the presence of actinomycin D, a transcription blocker. Results indicated that PMA treatment may induce both VIP mRNA synthesis as well as VIP mRNA stabilization, and suggested a 4-5 h half-life for the VIP mRNA in the absence of PMA. Thus, lung cancer tumor proliferation may be regulated, in part, at the level of VIP gene expression.

Rheumatoid factor idiotypic and antigenic specificity is strongly influenced by the light chain VJ junction

The aim of this study was to define the structural basis for rheumatoid factor (RF) specificity and for the expression of the RF light chain-associated Ids, 4C9 and 6B6.6, by determining the reactivity of recombined heavy and light chains of Ig derived from monoclonal B cell lines of patients with rheumatoid arthritis and of light chains with site-directed mutations. We found that expression of the 4C9 and 6B6.6 Ids resulted from use of the VkIIIa genes Humkv 328 and Vg, but only in the presence of a permissive VJ junction. Expression of the Ids was independent of heavy chain use for the Humkv328-encoded light chains, but was highly dependent on the associated heavy chain for the Vg-encoded light chains. The RF specificity of the Abs was primarily heavy chain dependent, but the light chain VJ junction was critical in determining the relative avidity of the Abs for Fc. Our study points to the critical contribution of the somatically generated VJ junction to RF autoantibody specificity and to the expression of the two RF-associated Ids studied.

Rheumatoid factor idiotypic and antigenic specificity is strongly influenced by the light chain VJ junction

The aim of this study was to define the structural basis for rheumatoid factor (RF) specificity and for the expression of the RF light chain-associated Ids, 4C9 and 6B6.6, by determining the reactivity of recombined heavy and light chains of Ig derived from monoclonal B cell lines of patients with rheumatoid arthritis and of light chains with site-directed mutations. We found that expression of the 4C9 and 6B6.6 Ids resulted from use of the VkIIIa genes Humkv 328 and Vg, but only in the presence of a permissive VJ junction. Expression of the Ids was independent of heavy chain use for the Humkv328-encoded light chains, but was highly dependent on the associated heavy chain for the Vg-encoded light chains. The RF specificity of the Abs was primarily heavy chain dependent, but the light chain VJ junction was critical in determining the relative avidity of the Abs for Fc. Our study points to the critical contribution of the somatically generated VJ junction to RF autoantibody specificity and to the expression of the two RF-associated Ids studied.

Ex vivo expansion of murine hematopoietic progenitor cells generates classes of expanded cells possessing different levels of bone marrow repopulating potential

The objective of ex vivo expansion of primitive hematopoietic progenitor cells (HPC) is to increase the number of progeny cells possessing hematopoietic potential similar to the original HPC. In the context of bone marrow (BM) transplantation in mice, this implies that expanding a number of HPC sufficient for long-term rescue of one lethally irradiated animal should generate enough cells to rescue more than one lethally irradiated recipient. In the present study, Sca-1+Lin- cells from male C57Bl/6 mice were expanded in vitro with stem cell factor (SCF), interleukin-1alpha (IL-1alpha), IL-3, and IL-6 and used to transplant lethally irradiated syngeneic female recipients. Expanded cells were tracked in vitro with the fluorescent membrane dye PKH2, which becomes evenly distributed among dividing daughter cells, and fractionated on day 7 into Sca-1+ cells which did not divide (Sca-1+PKH2bright), those which had divided 1 to 2 times (Sca-1+PKH2moderate), or those which had divided four or more times (Sca-1+PKH2dim). Grafts of expanded cells consisted of either the same number of fresh cells proven to rescue lethally irradiated animals [3X10(3) cells; referred to as one repopulating dose (1 RD)] or the expansion equivalent (EE) of these cells. One EE of cells represented 3X10(3) multiplied by the fold increase in the number of cultured cells on day 7. All animals transplanted with 3X10(3) freshly isolated Sca-1+Lin- cells survived long-term. Only 53% of animals receiving 1 EE of all cultured day-7 cells survived. One RD from all three PKH2 fractions (bright, moderate, and dim) of day-7 cultured Sca-1+ cells failed to rescue more than 30% of lethally irradiated recipients. Comparable survival rates were obtained when 1 EE of Sca-1+PKH2dim or only 4 RD of Sca-1+PKH2bright cells were used as grafts, suggesting that a larger frequency of long-term repopulating cells may have been retained within the fraction of Sca-1+ cells undergoing minimal or no proliferation in culture. Engraftment of male ex vivo expanded cells in recipients was confirmed by polymerase chain reaction (PCR) analysis with Y chromosome-specific primers. When analyzed for their cell cycle status, Sca-1+PKH2bright cells were mostly quiescent, whereas a higher percentage of Sca-1+PKH2dim cells were in active phases of cell cycle. These data suggest that ex vivo expansion does not augment the number of BM repopulating HPC and that ex vivo expansion generates classes of progenitor cells with different BM repopulating potentials depending on their proliferative history. These studies also suggest that the cell cycle status of graft cells may affect the ability of these cells to engraft in myeloablated hosts.

Effects of retinoic acid on cell differentiation and reversion toward normal in human endometrial adenocarcinoma (RL95-2) cells

BACKGROUND

All-trans retinoic acid is currently used in clinical trials in combination with tamoxifen to treat breast cancer, and 13-cis retinoic acid is used with a-interferon to treat metastatic endometrial cancer. We examined the effects of all-trans retinoic acid and 13-cis RA alone on endometrial adenocarcinoma (RL95-2) cells to investigate the cell biological mechanisms by which retinoic acid may reduce the metastatic phenotype and induce differentiation.

METHODS

RL95-2 cells were seeded onto 4-chamber plastic slides and treated with 13-cis retinoic acid or all-trans retinoic at 0.5 microM, 1 microM and 5 microM doses for 90 minutes at 37 degrees C and stained for F-actin.

RESULTS

Untreated RL95-2 cells exhibited staining of disrupted aggregates of F-actin only near the cell periphery. Cells treated with the three doses of 13-cis retinoic acid exhibited a dramatic reorganization of F-actin throughout the cells. When cells were treated with 0.5 microM all-trans retinoic acid, actin filaments reorganized. Cells treated with 1 microM all-trans retinoic acid and 5 microM all-trans retinoic acid displayed increased organization of F-actin and cell size increased. The percentage of S-phase cells increased at the high doses of retinoic acid treatment. This effect was apparently transient, since retinoic acid did not significantly affect cell growth.

CONCLUSION

An organized cytoskeleton and an increase in cell size are associated with differentiation. We suggest that retinoic acid exerts its effects on these transformed cells by reorganizing actin filaments, and inducing differentiation, thus inducing a more stationary phenotype.