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J M Agosti

Publications and source records attributed to J M Agosti.

34 records · Page 2Linked to original sources
PubMed1996

Granulocyte-macrophage colony-stimulating factor as infection prophylaxis in high-risk oncologic surgery.

BACKGROUND: A method of augmenting host defenses against bacterial pathogens could result in a decrease in postoperative infections. Given its effects on leukocyte proliferation and function, it is possible that prophylactic granulocyte-macrophage colony-stimulating factor (GM-CSF) could reduce the incidence and severity of infections in high-risk surgical patients. The current study was undertaken to determine the safety and hematologic effects of perioperative GM-CSF. METHODS: Cancer patients undergoing operations with a high risk of postoperative infection were treated perioperatively for 10 days with subcutaneous GM-CSF. Cohorts were treated with GM-CSF at 125 micrograms/m2/day (12 patients) and 250 micrograms/m2/day (11 patients). RESULTS: There were no severe or life-threatening toxicities associated with GM-CSF. Mean maximum neutrophil counts during the first 5 postoperative days were 16.3 +/- 9.14 and 24.5 +/- 7.60 at 125 and 250 micrograms/m2, respectively (P = 0.04). Only one wound infection was diagnosed during this study. CONCLUSIONS: GM-CSF may be safely administered perioperatively at doses that augment neutrophil number and function. An ongoing randomized clinical trial will determine the impact of GM-CSF on postoperative infection.

Bacterial Infections↗
PubMed1995

Effects of recombinant dimeric TNF receptor on human inflammatory responses following intravenous endotoxin administration.

Effects of dimeric TNF receptor (p80) Fc (TNFR:Fc) on acute phase responses were evaluated in 18 volunteers given endotoxin (4 ng/kg i.v.). Subjects were randomized to receive either placebo (n = 6), low dose TNFR:Fc (10 mg/m2 i.v., n = 6), or high dose TNFR:Fc (60 mg/m2 i.v., n = 6). TNFR:Fc blocked plasma TNF bioactivity (p = 0.001) and increased, in a dose-ordered fashion, TNF immunoactivity (p < 0.001). TNFR:Fc decreased secondary cytokine levels including IL-1 beta (p = 0.007), IL-8 (p < 0.001), IL-1 receptor antagonist (p < 0.001), granulocyte-CSF (p = 0.03), and growth regulated peptide-alpha (p = 0.001) but not macrophage inflammatory protein-1 alpha or IL-10. Low dose, but not high dose, TNFR:Fc blunted or delayed the release of epinephrine and cortisol (p < or = 0.026). Despite the absence of plasma TNF bioactivity, high dose TNFR:Fc was less immunosuppressive than low dose TNFR:Fc as measured by cytokine and stress hormone responses. Endotoxin-related symptoms were not altered by TNFR:Fc and the febrile response was delayed but not diminished (p = 0.004). Increases in cardiac index (72 +/- 19%) and heart rate (60 +/- 10%) and decreases in systemic vascular resistance index (47 +/- 7%) were unaltered by TNFR:Fc. These data suggest that the inflammatory response to endotoxin can escape from high levels of circulating TNF-blocking activity and redundant pathways, independent of circulating TNF, can sustain inflammation and clinical responses caused by acute endotoxemia.

Animals↗
PubMed1995

Results of a phase I/II trial of recombinant human granulocyte-macrophage colony-stimulating factor in very low birthweight neonates: significant induction of circulatory neutrophils, monocytes, platelets, and bone marrow neutrophils.

Neonates, especially those of very low birthweight (VLBW), have an increased risk of nosocomial infections secondary to deficiencies in development. We previously demonstrated that granulocyte-macrophage colony-stimulating factor (GM-CSF) production and mRNA expression from stimulated neonatal mononuclear cells are significantly less than that from adult cells. Recombinant murine GM-CSF administration to neonatal rats has resulted in neutrophilia, increased neutrophil production, and increased survival of pups during experimental Staphylococcus aureus sepsis. In the present study, we sought to determine the safety and biologic response of recombinant human (rhu) GM-CSF in VLBW neonates. Twenty VLBW neonates (500 to 1,500 g), aged < 72 hours, were randomized to receive either placebo (n = 5) or rhuGM-CSF at 5.0 micrograms/kg once per day (n = 5), 5.0 micrograms/kg twice per day (n = 5), or 10 micrograms/kg once per day (n = 5) given via 2-hour intravenous infusion for 7 days. Complete blood counts, differential, and platelet counts were obtained, and tibial bone marrow aspirate was performed on day 8. Neutrophil C3bi receptor expression was measured at 0 and 24 hours. GM-CSF levels were measured by a sandwich enzyme-linked immunosorbent assay at 2, 4, 6, 12, and 24 hours after the first dose of rhuGM-CSF. At all doses, rhuGM-CSF was well tolerated, and there was no evidence of grade III or IV toxicity. Within 48 hours of administration, there was a significant increase in the circulating absolute neutrophil count (ANC) at 5.0 micrograms/kg twice per day and 10.0 micrograms/kg once per day, which continued for at least 24 hours after discontinuation of rhuGM-CSF. When the ANC was normalized for each patient's first ANC, there was a significant increase in the ANC on days 6 and 7 at each dose level. By day 7, all tested doses of rhuGM-CSF resulted in an increase in the absolute monocyte count (AMC) compared with placebo-treated neonates. In those receiving rhuGM-CSF 5.0 micrograms/kg twice per day, there was additionally a significant increase in the day 7 and 8 platelet count. Tibial bone marrow aspirates demonstrated a significant increase in the bone marrow neutrophil storage pool (BM NSP) at 5.0 micrograms/kg twice per day and 10.0 micrograms/kg once per day. Neutrophil C3bi receptor expression was significantly increased 24 hours after the first dose of rhuGM-CSF at 5.0 micrograms/kg once per day. The elimination half-life (T1/2) of rhuGM-CSF was 1.4 +/- 0.8 to 3.9 +/- 2.8 hours.(ABSTRACT TRUNCATED AT 400 WORDS)

Birth Weight↗
PubMed1994

Dysregulation of cytokine expression in monocytes from HIV-positive individuals.

Because HIV may alter the production of inflammatory factors produced by monocytes, the expression of tumor necrosis factor alpha (TNF-alpha), tissue factor (TF), interleukin (IL)-1 beta, and IL-6 was evaluated in 47 HIV-seropositive persons and seronegative control subjects. RNA was extracted from freshly isolated lipopolysaccharide (LPS)-stimulated or unstimulated monocytes. Cytokine and TF expression was quantitated by dot blot hybridization or a reverse transcription polymerase chain reaction (RT-PCR). A significant depression of TF mRNA was observed in LPS-stimulated monocytes (66% less in AIDS, 20% less in AIDS-related complex (ARC), and 0% less in asymptomatic patients), whereas normal responses were observed for TNF-alpha, IL-1 beta, and IL-6. When constitutive expression was measured in unstimulated monocytes by RT-PCR, a differential pattern was also observed. TNF-alpha and IL-1 beta were positive in 85% of asymptomatic persons, compared with only 27% of ARC and 42% of AIDS patients. Expression of IL-6 was observed in lower proportions, 27-30%, with no significant differences among disease states. All samples were negative for TF. Thus, the regulation of inflammatory molecules is differentially altered in individuals with HIV infection. TF is preferentially down-regulated, compared with TNF-alpha, IL-1 beta, and IL-6, in LPS-stimulated monocytes as patients progress to AIDS. TNF-alpha and IL-1 beta are preferentially up-regulated, compared with IL-6 and TF, in unstimulated monocytes in asymptomatic persons, with a loss of up-regulation as patients progress to AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1992

A randomized, double-blind, phase I/II trial of tumor necrosis factor and interferon-gamma for treatment of AIDS-related complex (Protocol 025 from the AIDS Clinical Trials Group).

To determine safety and efficacy of tumor necrosis factor (TNF) and interferon-gamma (IFN gamma) in the treatment of patients with acquired immunodeficiency syndrome (AIDS)-related complex, a randomized, double-blind study was conducted. Twenty-five patients with AIDS-related complex and CD4 lymphocytes less than or equal to 500 x 10(6)/L attended an AIDS Clinical Trials Unit of a tertiary referral center. Patients were administered tumor necrosis factor (TNF) (10 micrograms/m2) or IFN gamma (10 micrograms/m2), or both intramuscularly three times weekly for 16 weeks. Side effects from all three preparations included fever, constitutional symptoms, and local reactions. No significant hematologic, hepatic, renal, or coagulation abnormalities were observed. CD4 lymphocyte counts, beta 2-microglobulin, p24 antigen levels, and anti-p24 antibody did not change significantly during therapy. Similarly, no significant change was noted in rates of HIV isolation from peripheral blood mononuclear cells or plasma. TNF and IFN gamma were tolerable after premedication with acetaminophen; however, no significant change in markers of human immunodeficiency virus infection was demonstrated. These cytokines alone do not appear to be of benefit, nor do they appear to hasten the progression of HIV infection.

AIDS-Related Complex↗
PubMed1990

A selective defect in tissue factor mRNA expression in monocytes from AIDS patients.

Expression of tumor necrosis factor (TNF alpha), tissue factor (TF), and interleukin 1-beta (IL-1 beta) mRNA was evaluated in monocytes isolated from patients infected with human immunodeficiency virus (HIV). There was a significant depression (66%) of the induced level of TF mRNA expression in response to lipopolysaccharide. Conversely, the response of TNF alpha and IL-1 beta, following LPS induction, was "normal." TF mRNA reduction was also observed to a lesser degree in AIDS-related complex patients (20%) but not in asymptomatic seropositives. TF is necessary for initiation of the coagulation protease cascade, leading to thrombin production and fibrin deposition, which play a role in inflammatory responses. Its selective reduction may be a factor in the diminished resistance to secondary infections observed in AIDS. Further, since the TF defect increases as patients progress toward AIDS, it may serve as a marker for disease progression.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Comparative toxicity of the horse eosinophil peroxidase-H2O2-halide system and granule basic proteins.

Stimulated eosinophils release cytotoxic granule constituents, including eosinophil peroxidase (EPO) and a group of granule basic proteins (GBP). EPO reacts with H2O2 formed by the respiratory burst and a halide to form cytotoxic oxidants. The relative potency of the EPO-H2O2-halide system and the GBP is considered here. Horse eosinophils were induced to degranulate, the degranulation products were separated by chromatography on Sephadex G-50 and comparable volumes of the column fractions were tested for toxicity to Escherichia coli and the schistosomula of Schistosoma mansoni in the presence and absence of H2O2 and halides. Both the EPO system and GBP were toxic. However, the peak EPO fraction could be diluted 1000-fold at pH 7.0 and 5000-fold at pH 5.0, and with a 10-fold dilution at pH 7.0 incubation time could be reduced to 5 s, with retention of bactericidal activity in the presence of H2O2 and halides, whereas the peak GBP fractions diluted 10-fold had a small bactericidal effect at 1 h which increased with prolongation of incubation to 24 h. A less than 1 log fall in E. coli viable cell count was produced by the GBP fractions under all conditions as compared to total destruction (greater than 5 log fall) with the EPO system. A 1000-fold dilution of the peak EPO fraction was schistosomulocidal in the presence of H2O2 and halides, with toxicity observed at 2 h with a 10-fold dilution. In contrast, no schistosomulocidal activity was observed at 18 h with a 10-fold dilution of the GBP fractions. However, toxicity was observed with a 5- or 50-fold increase in GBP concentration with maximum toxicity observed with fractions between the two major protein peaks. Thus, under the conditions employed, the EPO-H2O2-halide system contributed to a considerably greater degree to the toxic activity of the granule components than did the GBP.

Animals↗
PubMed1989

Injurious effect of the eosinophil peroxide-hydrogen peroxide-halide system and major basic protein on human nasal epithelium in vitro.

Tissue injury is observed in allergic and nonallergic eosinophilic rhinitis, but the mechanism of this injury is unclear. Because eosinophils are prominent in biopsy specimens in these conditions, we hypothesized that they may participate in the injury process. Initially, we developed techniques to isolate and purify human nasal epithelial cells from turbinate biopsies to use as target cells for eosinophil granule products. Primary cultures from explants were characterized by electron microscopy and indirect immunofluorescence with a panel of primary monoclonal and polyclonal antibodies. These studies revealed the homogeneity of the cells and confirmed their epithelial nature. Cultured nasal epithelial cells were then exposed to either purified human eosinophil peroxidase, bromide, and glucose plus glucose oxidase, as a continuous source of hydrogen peroxide, or eosinophil major basic protein. Neither eosinophil peroxidase alone nor glucose plus glucose oxidase in the absence of eosinophil peroxidase were injurious, but the combined addition of eosinophil peroxidase, glucose/glucose oxidase, and bromide produced marked target cell lysis. This effect was time- and eosinophil peroxidase dose-dependent. Catalase and azide significantly inhibited the lysis of these cells, suggesting the eosinophil peroxidase-catalyzed products of halide oxidation mediated this form of injury. The addition of purified human eosinophil major basic protein also caused dose- and time-dependent lysis of the nasal epithelial cells but required longer incubation periods to effect injury. We hypothesize that the eosinophil peroxidase-hydrogen peroxide-halide system and major basic protein may injure the nasal epithelium in inflammatory conditions such as allergic and nonallergic eosinophilic rhinitis.

Blood Proteins↗
PubMed1988

Transfer of allergen-specific IgE-mediated hypersensitivity with allogeneic bone marrow transplantation.

We investigated whether allergen-specific IgE-mediated hypersensitivity is transferred by bone marrow transplantation. Twelve patients, 14 to 47 years of age, undergoing allogeneic bone marrow transplantation for the treatment of hematologic cancer were selected, along with their donors, by a screening questionnaire for a history of atopy in the donor. We evaluated these donor-recipient pairs before transplantation and at several points afterward for immediate skin-test reactivity to 17 allergens. For allergens for which pretransplantation skin tests had been positive in the donors and negative in the recipients, 20 of 46 post-transplantation skin tests were positive in 8 of the 11 recipients who survived for more than one year after transplantation. For allergens for which both donors and recipients had had negative skin tests before transplantation, only 6 of 256 tests (2.3 percent) were positive in the recipients after transplantation. Long-term transfer of donor-derived mite-specific IgE was demonstrated by radioallergosorbent testing in two recipients. Seven recipients either acquired or had an exacerbation of allergic rhinitis, and two recipients without a history of asthma had asthma one year after transplantation. We conclude that allergen-specific IgE-mediated hypersensitivity is adoptively transferred by bone marrow transplantation from donor to recipient by B cells with allergen-specific memory.

Adolescent↗
PubMed1987

The injurious effect of eosinophil peroxidase, hydrogen peroxide, and halides on pneumocytes in vitro.

Recent data suggest that eosinophils may cause lung injury. To determine if the eosinophil peroxidase (EPO)-hydrogen peroxide (H2O2)-halide system could mediate this injury, we added human EPO, H2O2 (or glucose and glucose oxidase as a continuous source of H2O2), and various halides to monolayers of 51Cr-labeled human A549 and rat type II pneumocytes. Cell lysis was measured as soluble 51Cr release. In initial experiments, EPO in solution did not induce lysis under these conditions. Therefore, in subsequent experiments, pneumocytes were preincubated with EPO for 15 minutes, washed to remove unbound enzyme, and then glucose, glucose oxidase, and the halides were added. EPO alone was not injurious, nor was the addition of glucose and glucose oxidase in the absence of EPO. In contrast, the combined addition of EPO, glucose, glucose oxidase, and chloride produced marked target-cell lysis. This effect was time and EPO dose dependent and was enhanced by the addition of iodide. Catalase and azide substantially inhibited the lysis produced by the EPO-H2O2-halide system, suggesting that EPO-catalyzed products of halide oxidation mediated this form of injury. Finally, the addition of eosinophil major basic protein at 10(-5) mol/L to EPO-coated pneumocytes incubated with glucose, glucose oxidase, and halides failed to enhance or inhibit lysis. We hypothesize that the EPO-H2O2-halide system may injure the lung in asthma and eosinophilic pulmonary syndromes.

Animals↗
PubMed1986

Stimulation of neutrophils by tumor necrosis factor.

Human recombinant tumor necrosis factor (TNF) was shown to be a weak direct stimulus of the neutrophil respiratory burst and degranulation. The stimulation, as measured by iodination, H2O2 production, and lysozyme release, was considerably increased by the presence of unopsonized zymosan in the reaction mixture, an effect which was associated with the increased ingestion of the zymosan. TNF does not act as an opsonin but, rather, reacts with the neutrophil to increase its phagocytic activity. TNF-dependent phagocytosis, as measured indirectly by iodination, is inhibited by monoclonal antibodies (Mab) 60.1 and 60.3, which recognize different epitopes on the C3bi receptor/adherence-promoting surface glycoprotein of neutrophils. Other neutrophil stimulants, namely N-formyl-methionyl-leucyl-phenylalanine, the Ca2+ ionophore A23187, and phorbol myristic acetate, also increase iodination in the presence of zymosan; as with TNF, the effect of these stimulants is inhibited by Mab 60.1 and 60.3, whereas, in contrast to that of TNF, their stimulation of iodination is unaffected by an Mab directed against TNF. TNF may be a natural stimulant of neutrophils which promotes adherence to endothelial cells and to particles, leading to increased phagocytosis, respiratory burst activity, and degranulation.

Cytoplasmic Granules↗