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Biomedical subjects

D L Longo

Publications and source records attributed to D L Longo.

At least 289 records · Page 16Linked to original sources
PubMed1991

The in vivo immunomodulatory effects of recombinant interferon gamma plus recombinant tumor necrosis factor-alfa.

We conducted a phase I study in which an intramuscular injection of interferon gamma (IFN gamma) at 10, 50, or 100 micrograms/m2 was followed 5 minutes later by an intramuscular injection of 10, 50, or 100 micrograms/m2 of tumor necrosis factor-alfa (TNF alpha) at another site every other day for 20 days (10 doses). The addition of TNF alpha to IFN gamma reduced both the magnitude and duration of IFN gamma-mediated effects on peripheral blood monocyte expression of Fc receptors (FcRs) and HLA-DR and production of hydrogen peroxide. This inhibition was related to the dose of TNF alpha. On the other hand, TNF alpha and IFN gamma appeared to have an additive stimulatory effect on the production of neopterin by monocytes. The highest serum levels of neopterin were detected in patients who received the highest doses of both IFN gamma and TNF alpha. Thus, conflicting conclusions regarding the effect of the combination on immune activation are possible. If the activation of peripheral blood monocytes is the appropriate surrogate measure of the immune enhancement of the combination, then the simultaneous administration of IFN gamma and TNF alpha is ineffective, and future attempts to exploit the potential additive or synergistic effects of this combination of cytokines in humans may need to explore sequential administration schemata. On the other hand, if serum neopterin levels are a more reliable index of immune activation, simultaneous administration of 100 micrograms/m2 IFN gamma and 50 micrograms/m2 TNF alpha every other day (the maximally tolerated dose [MTD]) should be used in phase II testing. This dilemma points out the limitations of currently available methods of human immune assessment and the inadequacies in our capacity to gauge what particular immune measure or set of measures predict for in vivo antitumor effects.

Analysis of Variance↗
PubMed1991

The calculation of actual or received dose intensity: a comparison of published methods.

Two recent reports of the same combination chemotherapy program, cyclophosphamide, doxorubicin, etoposide, methotrexate, cytarabine, vincristine, bleomycin, and prednisone (ProMACE-CytaBOM), in similar subsets of patients with advanced-stage aggressive-histology lymphoma used two different methods to report the actual dose-intensity (DI) data. One method treats DI as a property of a particular cycle of treatment within the entire population that received that cycle. The other treats DI as a characteristic of a particular patient's entire treatment course. We have applied both methods to the same set of data and provide evidence that the latter method is preferable for at least two reasons: (1) it more accurately reflects actual DI by clearly incorporating the duration of the actual treatment course and, thus, can be used to compare the administration of same or related regimens to distinct patient populations; and (2) it allows assignment of a numerical value to an individual patient's treatment course or a group of patients' treatment courses such that DI can be examined for its impact on treatment outcome just like any other prognostic factor. The observed differences in treatment outcome between the Southwest Oncology Group (SWOG) and National Cancer Institute (NCI) studies are not clearly related to differences in distribution of clinical prognostic factors in the two study populations. The differences in methods of reporting DI prohibit evaluation of the influence of dose-related variables on outcome in the two studies. Adoption of a standard method of calculating and reporting DI data would facilitate evaluation of the prognostic significance of DI.

Aged↗
PubMed1991

Clinical evaluation of intraperitoneal Pseudomonas exotoxin immunoconjugate OVB3-PE in patients with ovarian cancer.

OVB3-PE is an immunotoxin composed of a murine monoclonal antibody reactive with human ovarian cancer and conjugated to Pseudomonas exotoxin (PE). Twenty-three patients with refractory ovarian cancer were treated intraperitoneally (IP) with escalating doses of OVB3-PE to study toxicity, pharmacokinetics, antiimmunotoxin antibody formation, and antitumor response. Dose-limiting CNS toxicity occurred after repeated doses at 5 and 10 micrograms/kg. Other non-dose-limiting toxicities included transient elevation of liver enzymes, fever, and gastrointestinal toxicity. Pharmacokinetics of IP and serum OVB3-PE were determined in 16 patients. Peak peritoneal fluid levels exceeded the in vitro median effective dose at all doses tested. At doses of 1 to 2 micrograms/kg, the immunotoxin concentration in the peritoneal fluid remained constant for up to 8 hours and dropped to negligible levels after 12 hours. At the 5 and 10 micrograms/kg doses, levels remained high for up to 24 hours (greater than 100 ng/mL) and then gradually decreased and became undetectable (less than 4 ng/mL) after 72 hours. Serum levels of OVB3-PE were also analyzed in 16 patients. At doses of 1 micrograms/kg and 2 micrograms/kg, serum levels were not detectable (less than 5 ng/mL). However, after doses of 5 or 10 micrograms/kg, peak serum level occurred at 24 hours after each dose and dropped to negligible levels by 72 hours. Sera from 12 patients were analyzed for anti-PE antibodies and antibodies to mouse immunoglobulin (HAMA). All patients developed antibodies against PE within 14 days of therapy. Domain II of PE appeared to be the most immunogenic portion of the PE molecule. HAMA was detected on day 14 of therapy in nine patients, on day 21 in two, and on day 28 in one patient. No clinical antitumor responses were observed. We conclude that IP OVB3-PE at dose levels of 5 micrograms/kg (x 3) and 10 micrograms/kg (x 2) is accompanied by dose-limiting toxic encephalopathy. Neurologic toxicity is likely to be due to crossreactivity of OVB3 to normal human brain tissue, which was not appreciated during preclinical screening.

ADP Ribose Transferases↗
PubMed1991

Treatment of advanced-stage massive mediastinal Hodgkin's disease: the case for combined modality treatment.

In the initial series of 198 patients treated at the National Cancer Institute (NCI) with mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) chemotherapy for Hodgkin's disease, a review of presenting chest radiographs available on 192 of these patients showed 49 patients with mediastinal masses greater than one third the greatest posteroanterior chest diameter. Five patients had stage IIB disease, and 44 had stage III or IV disease. Thirty-five (71%) patients achieved a complete remission with MOPP chemotherapy. Fourteen (40%) of the complete responders relapsed, but four of these achieved durable remissions in response to subsequent therapy. Thirty (61%) patients have died (14 induction failures, nine relapsed patients, seven complete responders in remission). Thus, with a median follow-up of 20 years (range, 15 to 23), the overall survival for the group is 39%, and the disease-free survival for the complete responders is 60%. A subset of 10 patients received mantle radiation therapy after maximal response to MOPP. One of these patients failed to achieve complete remission, but among the nine complete responders only one has relapsed. In contrast, 13 of 26 (50%) patients achieving a complete response to MOPP alone have relapsed (P2 = .0536). Although MOPP alone was not prospectively compared with MOPP plus radiation therapy in the treatment of advanced-stage massive mediastinal Hodgkin's disease in this series, the retrospective analysis shows a nearly significant difference in disease-free survival favoring combined modality treatment. The difference in tumor mortality between MOPP-treated (44%) and combined modality-treated patients (80%) was also nearly significant (P2 = .055). However, overall survival differences between patients treated with MOPP alone and those treated with combined modality therapy were not significantly different (P2 = 0.23) because of the mortality related to late complications of combined modality treatment.

Adolescent↗
PubMed1991

Radiation therapy versus combination chemotherapy in the treatment of early-stage Hodgkin's disease: seven-year results of a prospective randomized trial.

The study population included 136 patients with stage IA, IB, IIA, IIB, or IIIA1 Hodgkin's disease. The median follow-up is 7.5 years. Among the 30 patients with peripheral IA disease, all patients achieved a complete response (CR) with radiation therapy, and no patient has relapsed. Patients of other stages were randomized to receive radiation therapy or mechlorethamine, vincristine, procarbazine, and prednisone (MOPP). Among the 51 patients randomized to receive radiation therapy, 49 (96%) achieved complete remission, 17 (35%) have relapsed, and 10 (20%) have died. Fifty-two of the 54 (96%) assessable patients randomized to receive MOPP obtained CRs, seven (13%) have relapsed, and four (7%) have died. The projected 10-year disease-free survival of patients randomized to receive radiation therapy is 60%; for those randomized to receive MOPP, it is 86% (P2 = .009 in favor of MOPP). The projected 10-year overall survival for patients randomized to radiation therapy is 76%, and for MOPP-treated patients it is 92% (P2 = .051 in favor of MOPP). When the randomized patients with massive mediastinal disease or stage IIIA1 disease were excluded from the analysis, the disease-free (67% for radiation v 82% for MOPP) and overall survival (85% for radiation v 90% for MOPP) were not significantly different between the two arms. Subset analysis showed significant superiority of MOPP in the treatment of the following patient groups: stage IIIA1 or massive mediastinal disease, no B symptoms, initial erythrocyte sedimentation rate greater than 20 mm, four or more sites of disease, and younger than age 40 years. Preliminary analysis of this ongoing study shows that MOPP chemotherapy is at least as effective as radiation therapy in the treatment of the specific groups of early-stage Hodgkin's disease patients randomized. The final assessment of these two diverse treatment options will depend largely on the long-term survival and the incidence of early- and late-treatment complications for which patients are continuing to be observed.

Adolescent↗
PubMed1991

Treatment of advanced-stage Hodgkin's disease: alternating noncrossresistant MOPP/CABS is not superior to MOPP.

One hundred twenty-five assessable patients with advanced-stage Hodgkin's disease were randomized to receive mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) or MOPP alternating with lomustine (CCNU), doxorubicin, bleomycin, and streptozocin (CABS). The median follow-up is 7.7 years. The complete response rate was 60 of 66 MOPP-treated patients (91%) and 54 of 59 MOPP/CABS-treated patients (92%) (difference not significant). The level of the disease-free survival curve at longest follow-up is 65% for MOPP-treated patients and 72% for MOPP/CABS-treated patients (difference not significant). The overall survival at 12 years is projected at 68% for MOPP-treated patients and 54% for MOPP/CABS-treated patients (difference not significant). Thus, there were no significant differences in efficacy between MOPP and MOPP/CABS. However, MOPP/CABS was more emetogenic than MOPP, and four MOPP/CABS-treated patients went on to develop secondary acute leukemia. No MOPP-treated patients developed leukemia. High initial erythrocyte sedimentation rate (ESR) and high platelet counts adversely affected treatment outcome. MOPP-treated patients who received greater than 81% of the projected dose intensity of vincristine over the first three cycles had significantly improved disease-free survival rates over those receiving less than 81%. MOPP/CABS-treated patients who received greater than 82% of the projected dose intensity of vincristine had significantly better overall survival than those who received less than 82%. Disease-free survival on both arms was significantly better in patients who received greater than 84% of the projected dose intensity of all agents. The effect of dose intensity was particularly apparent in patients with poor prognostic factors where those who received greater than 84% of the projected dose intensity of all agents had significantly improved disease-free and overall survival.

Acute Disease↗
PubMed1991

p34cdc2 is physically associated with and phosphorylated by a cdc2-specific tyrosine kinase.

The mammalian homologue of the yeast cdc2 gene encodes a 34-kilodalton serine/threonine kinase that is a subunit of M phase-promoting factor. Recent studies have shown that p34cdc2 is also a major tyrosine-phosphorylated protein in HeLa cells and that its phosphotyrosine content is cell cycle regulated and related to its kinase activity. Here, we show that cdc2 is physically associated with and phosphorylated in vitro by a highly specific tyrosine kinase. Tyrosine phosphorylation of cdc2 in vitro occurs at tyrosine 15, the same site that is phosphorylated in vivo. The association between the two kinases takes place in the cytosolic compartment and involves cyclin B-associated cdc2. Evidence is presented that a substantial fraction of cytosolic cdc2 is hypophosphorylated, whereas nuclear cdc2 is hyperphosphorylated. Finally, we show that the tyrosine kinase associated with cdc2 may be a 67-kilodalton protein and is distinct from src, abl, fms, and other previously reported tyrosine kinases.

Amino Acid Sequence↗
PubMed1991

Lymphomas.

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Peripheral clonal elimination of functional T cells.

A major mechanism for generating tolerance in developing T cells is the intrathymic clonal deletion of T cells that have receptors for those self antigens that are presented on hematopoietic cells. The mechanisms of tolerance induction to antigens not expressed in the thymus remain unclear. Tolerance to self antigens can be generated extrathymically through the induction of clonal nonresponsiveness in T cells with self-reactive receptors. A second mechanism of extrathymic tolerance was identified: clonal elimination of mature T cells with self-reactive receptors that had previously displayed functional reactivity.

Animals↗
PubMed1990

Chemoprotective effects of recombinant human IL-1 alpha in cyclophosphamide-treated normal and tumor-bearing mice. Protection from acute toxicity, hematologic effects, development of late mortality, and enhanced therapeutic efficacy.

In this study, recombinant human IL-1 alpha (rhIL-1 alpha) was used to protect normal and tumor-bearing BALB/c mice from the acute toxicity caused by lethal doses of cyclophosphamide (Cy) and 5-fluorouracil. Pretreatment of mice for 7 days with 10,000 U/day of rhIL-1 alpha protected 70 to 100% of mice from the acute death induced by lethal doses of both Cy (380 mg/kg) and 5-fluorouracil (250 mg/kg). In contrast, post-treatment of mice with single or multiple doses of rhIL-1 alpha was not chemoprotective. Pretreatment of mice with rhIL-1 alpha increased the acute LD90 of Cy from 380 mg/kg to greater than 500 mg/kg in normal mice, an LD90 dose-modifying effect of at least 1.25, was accompanied by a more rapid recovery from neutropenia and a less severe reduction in the number of bone marrow single lineage monocyte, myeloid, or myelomonocytic colonies. Some of the mice (10 to 50%) that were successfully protected by pretreatment with rhIL-1 alpha died after day 50. These mice consistently presented with extensive pulmonary inflammation and fibrosis at death. Mice bearing murine renal cancer (Renca) were also protected from the acute toxic effects of Cy (450 mg/kg) by pretreatment with rhIL-1 alpha. Renca-bearing mice pretreated with rhIL-1 alpha and either sublethal (300 mg/kg) or lethal (450 mg/kg) doses of Cy exhibited enhanced survival times over those of untreated Renca-bearing mice. Interestingly, the cause of death in Renca-bearing mice that ultimately failed treatment with rhIL-1 alpha plus 300 mg/kg Cy was recurrent tumor, whereas most mice treated with rhIL-1 alpha plus 450 mg/kg Cy had no detectable tumor, although several died from late pulmonary inflammation and fibrosis. Thus, the dose escalation of Cy in rhIL-1 alpha-pretreated mice results in greater antitumor effects of Cy. However, the dose escalation of some cytotoxic agents allowed by the use of myelostimulatory agents can result in late fatal complications not detected in acute toxicity testing.

Animals↗
PubMed1990

Transforming growth factor beta downregulates interleukin-1 (IL-1)-induced IL-6 production by human monocytes.

We investigated the effects of transforming growth factor beta (TGF beta) on the induction by interleukin-1 beta (IL-1 beta) of IL-6 in human monocytes. We found that IL-1 beta induced IL-6 messenger RNA expression in elutriated monocytes and IL-6 secretion in the supernatant. TGF beta did not induce IL-6. In contrast, TGF beta added to the culture inhibited, in a dose-dependent manner, the induction of IL-6 by IL-1 at the level of messenger RNA and bioactivity. These results show that IL-1 beta is able to stimulate IL-6 production by monocytes, TGF beta, by inhibiting this effect, may play an important role in regulating the IL-1-mediated components of the inflammatory response.

Blotting, Northern↗
PubMed1990

Anti-asialo GM1 antiserum treatment of lethally irradiated recipients before bone marrow transplantation: evidence that recipient natural killer depletion enhances survival, engraftment, and hematopoietic recovery.

Natural killer (NK) cells are reported to have an important role in the resistance of lethally irradiated recipients to bone marrow transplantation (BMT). Therefore, we investigated the effects of recipient NK depletion on survival, chimerism, and hematopoietic reconstitution after lethal irradiation and the transplantation of limiting amounts of T-cell-deficient bone marrow (BM). When administered before BMT, anti-asialo GM1 (ASGM1) antiserum treatment, effective in depleting in vivo NK activity, was associated with a marked increase in survival in 3 of 3 allogeneic combinations (BALB/c into C3H/HeN, C57B1/6, or C3B6F1). This enhanced survival was independent of the susceptibility of each recipient strain to accept BALB/c BM. Moreover, recipient anti-ASGM1 treatment was also effective in increasing survival in recipients of syngeneic BM, suggesting that NK cells can adversely affect engraftment independent of genetically controlled polymorphic cell surface determinants. Analysis of chimerism in surviving animals 2 months post-BMT showed that recipient NK depletion significantly increased the level of donor engraftment when high doses of BM were transplanted. These studies also demonstrated that anti-ASGM1 pretreatment mainly resulted in an increase in extramedullary hematopoiesis in the second and third week after irradiation. Anti-ASGM1 treatment also dramatically accelerated the rate of appearance of donor-derived cells with a higher level of donor-cell engraftment apparent at a time when the differences in survival between NK-depleted and control BMT recipients became significant. Peripheral cell counts were also affected by NK depletion, with significantly enhanced platelet and red blood cell recovery and a moderate increase in granulocyte recovery. The overall favorable influence of anti-ASGM1 recipient treatment on hematopoietic events post-BMT suggests that, in humans, pretransplant regimens aimed toward NK depletion should be evaluated.

Animals↗
PubMed1990

IL-2 enhances c-fms expression in human monocytes.

We investigated the effects of IL-2 and IFN-gamma on the expression of the proto-oncogene c-fms mRNA, which encodes for the macrophage CSF receptor. Low constitutive expression of c-fms mRNA was detected in fresh human monocytes. Stimulation of monocytes with IL-2 induced a significant increase in c-fms mRNA relative to medium control that was observed as early as 6 h after IL-2 stimulation. Dose-response experiments showed that 100 U/ml of IL-2 were sufficient to enhance the expression of c-fms mRNA. In contrast, IFN-gamma did not modify the levels of c-fms transcript. Immunoprecipitation experiments demonstrated that IL-2 enhanced c-fms glycoprotein levels. Experiments in which monocytes were activated with IFN-gamma or IL-2 followed by macrophage CSF-1 and then tested for tumoricidal activity demonstrated that macrophage CSF-1 sustained the cytotoxic activity induced by IL-2 but not by IFN-gamma. These data demonstrate that IL-2 enhances c-fms mRNA and c-fms glycoprotein expression suggesting that IL-2, by augmenting expression of macrophage CSF-1 receptors, can lead to prolongation of monocyte-mediated tumoricidal activity obtained in the presence of exogenous macrophage CSF-1.

Colony-Stimulating Factors↗
PubMed1990

Exacerbation of symptoms of autoimmune disease in patients receiving alpha-interferon therapy.

The occurrence of autoimmune disease in patients receiving alpha-interferon (alpha-IFN) therapy has been reported in several studies; these include autoimmune thyroiditis, thrombocytopenia, anemia, exacerbation of psoriasis, and the occurrence of sarcoidosis. The primary mechanism presumably is the emergence of autoantibodies to various structural proteins or receptors. Two studies have recently shown that a significant percentage of patients treated with recombinant alpha-interferon (r alpha-IFN) do form autoantibodies. The authors report six additional cases of development or exacerbation of autoimmune phenomena in patients receiving alpha-IFN therapy. Five of these patients developed symmetric polyarthropathies and the sixth had thyroiditis. The presence of a history of underlying autoimmune disease or baseline serologic abnormalities in five of these patients, including the patient who developed thyroiditis, suggests that alpha-IFN treatment can lead to the exacerbation of an underlying subclinical autoimmune process.

Adult↗
PubMed1990

Phase I and immunomodulatory study of a muramyl peptide, muramyl tripeptide phosphatidylethanolamine.

Muramyl tripeptide phosphatidylethanolamine (MTP-PE; CGP 19835A from Ciba Geigy) is a synthetic muramyl tripeptide structurally related to bacterial cell wall constituents. MTP-PE activates monocytes in vitro to a tumoricidal state and has in vivo antitumor effects in animal models. We studied the toxicity and immunomodulatory effects of once weekly i.v. administration of liposomal-encapsulated MTP-PE for 8 weeks in 27 patients with advanced malignancies. Doses ranged from 0.1 to 2.7 mg/m2. No major tumor responses were seen; 11 patients had stable disease after 8 weeks of therapy and 3 continued on maintenance therapy because of minor tumor regressions and/or clinical improvement. MTP-PE at these doses was well tolerated. Shaking chills and fevers were the most common toxicities and occurred at all dose levels. There was no treatment-induced loss of performance status. Immunomodulatory studies revealed evidence of a biological effect on monocytes. C-reactive protein levels rose in the majority of patients with end-of-treatment values 2 to 10 times higher than baseline. Serum neopterin levels were consistently increased 24 h after MTP-PE administration and significant decreases in expression of two different types of Fc receptors on peripheral blood monocytes were noted 6 h after treatment. Although no major tumor responses were seen in this group of patients with advanced malignancies, MTP-PE was well tolerated and exerted biological effects on monocytes. Serum neopterin levels may be a useful marker for the biological effects of MTP-PE.

Acetylmuramyl-Alanyl-Isoglutamine↗