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At least 559 records · Page 31Linked to original sources
PubMed1989

Stimulation of human hematopoietic progenitor cell proliferation and differentiation by recombinant human interleukin 3. Comparison and interactions with recombinant human granulocyte-macrophage and granulocyte colony-stimulating factors.

Recombinant human interleukin 3 (IL3) produced in Escherichia coli was purified and its activities examined in cultures of highly enriched human bone marrow progenitor cells. Human IL3 stimulated multipotential (CFU-GEMM) and erythroid (BFU-E) progenitor cells, generating 95% more BFU-E than recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF). No further enhancement of BFU-E or CFU-GEMM occurred when IL3 and GM-CSF were used in combination. Human IL3 was more effective than GM-CSF in stimulating granulocyte-macrophage colony-forming cells (CFU-GM) in short-term suspension cultures, but did not induce an increase of CFU-GM, BFU-E, or CFU-GEMM above input levels. IL3 was more active on day-14 (d14) than on d7 CFU-GM, similar to GM-CSF, but generated fewer and smaller CFU-GM-derived clones than either GM-CSF or granulocyte CSF (CI-CSF). The simultaneous addition of plateau levels of IL3 and GM-CSF resulted in an infra-additive augmentation of d7 and d14 CFU-GM-derived clones, whereas IL3 and G-CSF enhanced the number and cellularity predominantly of d14 CFU-GM. In liquid cultures, IL3 induced a greater than 100-fold increase in the number of basophil-mast-like cells and eosinophils and allowed maintenance of these cultures for up to 7 weeks. Human GM-CSF was an almost equally potent, stimulus of eosinophil development but had only a marginal effect on basophilic precursors, whereas G-CSF lacked both activities. Therefore, human IL3 is a multilineage hemopoietic growth factor whose activities appear to encompass and extend beyond those of GM-CSF.

Adult↗
PubMed1989

Phase I trial of recombinant human gamma-interferon and recombinant human tumor necrosis factor in patients with advanced gastrointestinal cancer.

Recombinant human gamma-interferon and recombinant human tumor necrosis factor are two representatives of a new class of antineoplastic agents. In vitro studies have suggested synergistic cytotoxic activities when the agents are combined. We report a phase I study of these two agents when administered daily for 5 consecutive days every 2 weeks in patients with advanced gastrointestinal cancers. Toxicity resulting from these agents was significant with hyperbilirubinemia representing the dose-limiting toxicity. Significant, although transient, myelosuppression was also observed. The maximal tolerated doses were 150 micrograms/m2/day for 5 days for each agent. Suggestive antineoplastic activity in biliary and pancreatic cancer was observed. Phase II trials of this combination are currently in progress.

Adult↗
PubMedDate not supplied

A phase I/II study of recombinant tumor necrosis factor and recombinant interferon gamma in patients with AIDS-related complex.

A clinical trial was conducted to determine the tolerance and toxicity of recombinant tumor necrosis factor (rTNF) and recombinant interferon gamma (rIFN-gamma) when administered concurrently by continuous intravenous infusion to 11 patients with the AIDS-related complex (ARC). In addition, HIV culture, p24 antigen levels, and CD4 positive lymphocytes were monitored to obtain preliminary evidence of antiviral and immunologic effects. Two 5-day treatment cycles were separated by a 9-day washout period. Two patients were entered at each dosage level and each patient received the two 5-day treatment cycles at two sequential dose levels ranging from 1 to 25 micrograms/m2. Two patients did not complete their second treatment cycle--one due to the development of a rash, the second due to central venous catheter discomfort. The occurrence of phlebitis with peripheral vein administration of these agents necessitated administration via central venous catheter. With the exception of a single patient who developed severe headache at the 25 micrograms/m2 dose, severe clinical toxicities were not observed. Fever, chills, headache, and myalgias were the most significant clinical toxicities observed and all were dose dependent. The percentage fall in total granulocytes was dose dependent and ranged from 17% at the 1 microgram/mm2 dose to 48% at both the 15 and 25 micrograms/mm2 dose levels. The mean nadir granulocyte count was 1694/mm3. No significant renal or hepatic toxicity was observed. Of 22 treatment cycles the CD4 cell number was increased in 11, unchanged in 7, and decreased in 4. The mean CD4 cell number did not change significantly (176 +/- 143/mm3 pretherapy versus 279 +/- 305/mm3 posttherapy).(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Related Complex↗
PubMed1988

Modulation of human neutrophilic granulocyte functions by recombinant human tumor necrosis factor and recombinant human lymphotoxin. Promotion of adherence, inhibition of chemotactic migration and superoxide anion release from adherent cells.

Recombinant human tumor necrosis factor (TNF) and recombinant human lymphotoxin (LT) were analyzed for their effects on inflammation-related functions of human polymorphonuclear neutrophilic granulocytes (PMN) in vitro, TNF at a concentration of 10 U/ml (corresponding to 10(-11) mol/l) enhanced PMN adherence to nylon fibres. It strongly inhibited the chemotactic migration of PMN in the Boyden chamber assay towards the chemotactic tripeptide formyl-methionyl-leucyl-phenylalanine (FMLP), C5a, LTB4 and a monocyte-derived chemotaxin (MOC) without affecting random migration and without being chemotactic itself. It did not stimulate superoxide anion (-O2.) production of PMN in suspension. However, it induced considerable -O2. release from PMN that had become adherent on nylon fibres. All these effects were abrogated by prior incubation of the cytokine with polyclonal and monoclonal antibodies against TNF. LT concentrations of 1,000 U/ml or higher were required to observe a moderate inhibition of chemotactic migration towards the above chemotactic factors and to elicit some -O2. production from nylon fibre-adherent PMN. LT did not increase the adherence of PMN to nylon fibres and it was not chemotactic. The results indicate that TNF is a potent modulator of PMN functions.

Cell Adhesion↗
PubMed1987

Immunomodulatory and immunotherapeutic properties of recombinant gamma-interferon and recombinant tumor necrosis factor in mice.

These studies were designed to examine the immunodulatory and immunotherapeutic properties of recombinant murine interferon gamma (rM IFN-gamma) and recombinant human tumor necrosis factor (rH TNF). We report that rM IFN-gamma activated murine natural killer cells and macrophages in a dose-dependent manner in vivo. The rM IFN-gamma, which demonstrated a bell-shaped therapeutic response curve, must be administered at specific doses and schedules to produce optimal therapeutic activity. Optimal activity was observed after i.v. administration of 50,000 U/animal rM IFN-gamma three times per week. In contrast, rH TNF produced its major therapeutic activity in the treatment of metastatic disease after i.v. but not i.p. administration. The therapeutic effects of rH TNF were as great in these in vivo systems as those of rM IFN-gamma. Furthermore, rH TNF had additive therapeutic activity when administered in conjunction with suboptimal doses of rM IFN-gamma. Unlike rM IFN-gamma, rH TNF did not activate natural killer cells in vivo or in vitro but did augment in vivo and in vitro macrophage tumoricidal activity. It also had synergistic cytostatic properties with rM IFN-gamma for some murine tumor cell lines in vitro. High levels of rH TNF were readily detected in the serum with a half-life of approximately 30 min after i.v. administration. In contrast, only minimal serum TNF activity occurred after i.p. administration, suggesting that i.v. administration may more efficiently facilitate systemic therapeutic activity. In summary, rH TNF and rM IFN-gamma have therapeutic activity for metastatic disease as individual agents and additive therapeutic activity when used in combination. Furthermore, it appears that in addition to therapeutic potential as cytostatic agents, the immunomodulatory properties of rH TNF have a role in its therapeutic properties.

Animals↗
PubMed1987

In vitro growth inhibition of cisplatin-resistant human lung cancer cell lines by recombinant human tumor necrosis factor and/or recombinant human interferon-gamma by virtue of collateral sensitivity.

The colony-inhibitory effects of recombinant human tumor necrosis factor (rH-TNF) and recombinant human interferon-gamma (rH-IFN-gamma) were evaluated in four human lung cancer cell lines and their cisplatin-resistant sublines. The cell lines tested were PC-7 and PC-9 (adenocarcinoma), H69 and N231 (small cell lung cancer) and four cisplatin-resistant sublines, PC-7/1.0, PC-9/0.5, H69/0.2 and N231/0.2, which were 20.0, 7.1, 4.8 and 8.4 fold resistant to cisplatin, respectively, compared to the respective parental cell line in terms of IC50 in a soft agar colony assay. All parental cell lines were resistant to rH-TNF and rH-IFN-gamma, alone or in combination. However, two resistant sublines showed sensitivity to rH-TNF and rH-IFN-gamma. Colony formation by PC-9/0.5 was significantly inhibited, in the absence or presence of cisplatin, by 10(2) U/ml of rH-TNF (less than 50% of control) and the inhibition was synergistic with that produced by 10(3) or 10(4) U/ml of rH-IFN-gamma. RH-IFN-gamma inhibited the colony formation of H69/0.2 only at the highest concentration tested (10(4) U/ml) (less than 50% of control) and the combined effect with rH-TNF was additive. These results suggest that rH-TNF and rH-IFN-gamma may have some potential in overcoming cisplatin resistance by virtue of collateral sensitivity.

Cisplatin↗
PubMed1988

Synergistic enhancement of the antitumor activity of recombinant human TNF-alpha by recombinant human IFN-gamma.

The effect of recombinant human interferon-gamma (rHu-IFN-gamma) on the antitumor activity of recombinant human tumor necrosis factor (rHu-TNF-alpha) was examined in vitro and in vivo. rHu-IFN-gamma enhanced both cytostatic and cytocidal activity of rHu-TNF-alpha against most rHu-TNF-alpha-sensitive tumor cells in vitro. However, there was no correlation between the degree of enhancement by rHu-IFN-gamma and that of the susceptibility of tumor cells to rHu-TNF-alpha. The enhancing effect of rHu-IFN-gamma was most marked when tumor cells were treated with rHu-IFN-gamma either for 1 day before treatment with rHu-TNF-alpha or for the first day of the exposure to rHu-TNF-alpha. A marked enhancing effect of rHu-IFN-gamma was also observed in the in vivo antitumor activity of rHu-TNF-alpha against HMV-2 melanoma. A combined treatment with rHu-TNF-alpha and rHu-IFN-gamma in a patient with papillary adenocarcinomas was shown to be much more effective than treatment with rHu-TNF-alpha alone. These results suggest that combined treatment with both agents will have better results in clinical trials.

Adenocarcinoma↗
PubMed1988

Kinetics of the inhibition by plasminogen activator inhibitor 2 of urokinase isolated from human urine and recombinant microorganisms. Further evidence for correct tertiary structure of recombinant urokinase.

The specific plasminogen activator inhibitor 2 (PAI-2) from human placenta was used to compare the kinetics of inactivation of recombinant urokinase and urokinase from human urine. The inactivation of the enzymes proceeded with identical second order rate constants. The result is considered a further indication of corresponding 3-dimensional structures of urokinases from human urine and of recombinant origin.

Glycoproteins↗
PubMed1988

Distinction of partially purified human natural killer cytotoxic factor from recombinant human tumor necrosis factor and recombinant human lymphotoxin.

Natural killer cell cytotoxic factor (NKCF), a cytotoxic factor contributing to human natural killer cell-mediated cytotoxicity, was generated from lymphocyte-conditioned medium using various stimuli. Crude NKCF activity was concentrated, and partially purified by ammonium sulfate precipitation and gel filtration. NKCF activities eluted as two molecular weight peaks, corresponding to Mr 33,000-43,000 (pool I) and approximately Mr 5,000 (pool II). The cytotoxic activity and target specificity of the partially purified NKCFs were found to be different from both recombinant human TNF and recombinant human lymphotoxin. In the NKCF assay, up to 10(6) units/ml of TNF and lymphotoxin had virtually no effect, whereas both NKCFs lysed 22% (range 17-33%) of the NK-sensitive target K562. In contrast, TNF and lymphotoxin were active in a standard assay against the sensitive murine L929 fibroblast cell line in all concentrations tested (10(-1)-10(6) units/ml). In addition, the effect of these cytotoxic factors in a short-term (4-h) chromium-release assay using peripheral blood mononuclear cells as effector cells was tested: only NKCF (pool I), but not TNF, lymphotoxin, or low molecular weight NKCF (pool II), enhanced NK and lymphokine-activated killer cell cytolysis, both against the NK-sensitive target K562 and the NK-resistant melanoma cell line SK-MEL 30. Results were not affected in the presence of neutralizing antibodies against TNF. NKCF could, therefore, be distinguished from TNF and lymphotoxin with respect to their biological activities.

Cell Line↗
PubMed1988

Synergistic antitumor effects of immunotherapy with recombinant interleukin-2 and recombinant tumor necrosis factor-alpha.

The antitumor activity of combination therapy with recombinant tumor necrosis-alpha (rhTNF-alpha) and recombinant interleukin-2 (rhIL-2) was assessed against established immunogenic (MCA-106) and nonimmunogenic (MCA-102) sarcomas at both s.c. and visceral (hepatic) sites. C57BL/6 (B6) mice were treated with a single i.v. dose of rhTNF-alpha (2, 4, 6, or 8 micrograms) followed by rhIL-2 (25,000 U) i.p. thrice daily for 5 consecutive days. Synergistic effects as measured by regression of tumor, prolongation of survival, and improved cure rates were found using the combination of rhTNF-alpha plus rhIL-2 compared to rhTNF-alpha alone or rhIL-2 alone in the treatment of the immunogenic sarcoma MCA-106. No significant antitumor effects were observed against the nonimmunogenic MCA-102 sarcoma. These findings were similar for both s.c. and large single hepatic tumor models. The effect of the timing of rhIL-2 injections in relation to rhTNF-alpha administration (concurrent, 2, 4, or 6 days post single rhTNF-alpha dose) was also evaluated. Substantial tumor regression and increased survival times were seen in mice with s.c. tumors when rhIL-2 therapy was delayed as much as 48 h after rhTNF-alpha administration. No antitumor response was noted with the combination compared to rhTNF-alpha alone when rhIL-2 was delayed for greater than 4 days. No increase in lethal toxicity during treatment course of the combination of rhTNF-alpha and rhIL-2 was noted at any schedule compared to single agent rhTNF-alpha therapy. A possible role of rhTNF-alpha in regulation of IL-2-dependent antitumor activity in vivo is discussed.

Animals↗
PubMed1987

Interactions between purified murine colony-stimulating factors (natural CSF-1, recombinant GM-CSF, and recombinant IL-3) on the in vitro proliferation of purified murine granulocyte-macrophage progenitor cells.

Purified preparations of natural CSF-1 (nCSF-1), recombinant GM-CSF (rGM-CSF), and recombinant IL-3 (rIL-3), alone and in combination, were investigated for their proliferative effects on highly enriched murine granulocyte-macrophage progenitor cells (CFU-GM). These CFU-GM had cloning efficiencies of 62%-95% in the presence of 10% (vol/vol) pokeweed mitogen-stimulated spleen cell-conditioned medium, and contained few, if any (less than or equal to 3%), contaminating morphologically recognizable monocytes or lymphocytes. The combination of low concentrations of nCSF-1 plus rIL-3, or nCSF-1 plus rGM-CSF, increased colony number greater than additively compared to the sum of colony formation with each factor alone, whereas total aggregate (colony plus cluster) number increased additively. At plateau concentrations, the previous CSF combinations increased colony number additively. Colony size was increased when nCSF-1 plus either rGM-CSF or rIL-3 were added simultaneously at either low or plateau concentrations, when compared to the size of colonies with any of the CSFs alone. Addition of rGM-CSF plus rIL-3 demonstrated no cooperative proliferative effect on either colony number or size. It is likely that these effects are mediated at the progenitor cell level and do not require accessory cell participation.

Animals↗
PubMed1988

Enhanced myocardial salvage by combined treatment with recombinant single-chain urokinase-type plasminogen activator and recombinant human superoxide dismutase in a canine coronary thrombosis model.

Myocardial ischemia was induced by formation of an occlusive thrombus in the left anterior circumflex artery (LCX) in open chest dogs. The myocardial salvage by the fibrin specific recombinant single-chain urokinase-type plasminogen activator (r-scu-PA) alone and in combination with the oxygen radical scavenger human superoxide dismutase of recombinant origin (r-HSOD) was investigated. The three experimental groups were: group I (n = 4) did not receive any treatment after LCX thrombosis; in group II (n = 9) at 100 min after LCX thrombosis r-scu-PA (20 micrograms.kg1.min-1 i.v. for 30 min) was infused; dogs in group III (n = 8) received concomitant treatment with r-scu-PA and r-HSOD (10 mg.kg1 i.v. for 60 min). Percent of left ventricle at risk did not differ between the groups. Infarct size as percent of the risk zone was 45.3 +/- 8.0 in group I, 25.3 +/- 3.7 in group II (a less than or equal to 0.05 vs group I) and 14.9 +/- 3.2 in group III (a less than 0.05 vs group II). Incidence of reperfusion arrhythmias and increase in plasma creatine kinase were significantly diminished by r-HSOD when compared to dogs receiving r-scu-PA only. There were no significant differences in hemodynamic parameters between the groups. No changes in plasma fibrinogen were observed in r-scu-PA treated dogs. In conclusion, the combined treatment with r-scu-PA and r-HSOD yielded a significantly higher myocardial salvage versus thrombolytic treatment alone in a canine LCX thrombosis model.

Animals↗
PubMed1987

Induction of colony stimulating factor in vivo by recombinant interleukin 1 alpha and recombinant tumor necrosis factor alpha 1.

In response to a potent inflammatory challenge, such as Gram-negative endotoxin, a number of cytokines are induced that, in turn, mediate many of the pathophysiologic alterations associated with endotoxicity. In this study, we have observed two endotoxin-associated monokines, recombinant interleukin-1 alpha (rIL 1 alpha) and recombinant tumor necrosis factor alpha (rTNF alpha), to induce colony stimulating factor (CSF) in vivo. The CSF activities produced in response to rIL 1 alpha or rTNF alpha gave rise to a mixture of granulocyte-macrophage colonies and were induced in a dose- and time-dependent fashion, peaking within 3 hr of cytokine injection (preceding peak CSF induction by endotoxin by several hours). Combined injection of suboptimal concentrations of rIL 1 alpha and rTNF alpha were additive, and simultaneous injection of optimal concentrations of each failed to increase CSF levels over that observed with either cytokine alone. Unlike endotoxin, neither cytokine induced interferon in vivo. These findings extend our understanding of the cytokine cascade that is operative in an inflammatory response and may account for many of the observed hematopoietic alterations that accompany inflammation.

Animals↗
PubMed1985

The different effects of recombinant human interferon-gamma and recombinant human interferon-beta on the activation of natural killer cells.

Highly purified recombinant human interferon-gamma produced by Escherichia coli (ReIFN-gamma) was examined for ability to stimulate natural killer (NK) cell cytotoxic activity and antibody-dependent cell-mediated cytotoxicity in human peripheral blood lymphocytes (PBLs) in comparison with natural human interferon-gamma (IFN-gamma) and with recombinant human interferon-beta produced by E. coli (ReIFN-beta). The activity of ReIFN-gamma to stimulate NK cell cytotoxicity was about 10 times greater than that of ReIFN-beta and similar to that of IFN-gamma when PBLs were pretreated with each interferon for 16 hr. The effects of ReIFN-gamma were completely neutralized by a rabbit anti-ReIFN-gamma antibody, but not by a rabbit anti-ReIFN-beta. ReIFN-gamma did not show any significant NK-enhancing effect when it was added directly to the killing phase of standard 51Cr-release assay for 4 hr, while ReIFN-beta showed a marked effect. The time course study showed that the NK-activating effect of ReIFN-gamma was not expressed until 2 hr after the start of incubation, while that of ReIFN-beta was expressed rapidly and sufficiently within 15 min. This kinetic difference between ReIFN-gamma and ReIFN-beta was confirmed by an experiment using the Ca2+-pulse method, in which the killing rate in the Ca2+-dependent stage of NK cytolysis was increased by ReIFN-gamma, but only after 6 hr of preincubation, while the effect by ReIFN-beta was expressed rapidly at 30 min. These findings suggest that ReIFN-gamma and ReIFN-beta may stimulate NK cell cytotoxicity through different intracellular events after they bind to their receptors on the surface of NK cells.

Antibodies↗
PubMed1985

[Interferon (IFN) therapy (recombinant IFN-alpha-2C or recombinant IFN-gamma) in metastasized hypernephroma].

Recombinant interferon-alpha-2C (rec. IFN alpha-2C) and recombinant interferon-gamma (IFN-gamma) was studied in 12 patients with metastasized renal cell carcinoma. 8 patients were treated with IFN-alpha-2C: 1 patient achieved a complete remission, 2 patients showed mixed responses, and 2 had stabilisation of their disease. In 3 patients progressive disease was observed. IFN-gamma was studied in 4 patients; 2 patients showed stable and 2 progressive disease. Side effects of IFN-alpha treatment included influenza-like symptoms, moderate hematological toxicity and neurological symptoms. During treatment with IFN-gamma similar side effects were observed, although fever generally was more pronounced. All symptoms ceased after dosis reduction or discontinuation of treatment.

Adult↗
PubMedDate not supplied

[Genetic properties of phage lambda recombinant molecules. The effect of an inserted fragment on the hybrid yield and recombination with respect to the h- and vir-markers].

The yield of mature phages in lambda gt-lambda Dm34, lambda gt-lambda DM225 and lambda gt-lambda Dm234 is 2, 8 and 8 times lower (respectively) as compared to the wild type. The output of hvir-recombinants in lambda gt-lambda Dm225 is more than an order lower as compared to the other phages. As distinct from two other hybrids, the decrease in lambda gt-lamba DM225 yield cannot be explained by red-genotype and a shortening of the phage genome as well as the decrease in the output hvir-recombinants cannot be attributed to a decrease in the yield of mature particles and to a shortening of the distance between markers. The data obtained show a contribution of Drosophila DNA to the observed effects.

Animals↗
PubMed1980

[Morphologico-genetic study of the enzymology of T4 phage recombination. II. Effect of antimutational T4 DNA-polymerase on correction-type recombination].

Effect of temperature antimutator L42 allele of gene 43 of T4 phage on the parameters of correction-type mechanism of genetic recombination have been studied under permissive conditions. The effect of L42 was found to be marker- as well as distance-dependent, and the pattern of these dependences shows that in the presence of antitumor DNA polymerase the distribution of the length of the repair region becomes more sharp and the mean length of the repair region becomes shorter. From this, it is concluded that T4 DNA polymerase is directly involved in the repair of mismatched region in recombinational intermediates, excising non-matched DNA strand and then filling the gap arisen.

Alleles↗
PubMed1982

[Recombination in bacteriophage T4: the nature of the disturbances introduced into genetic recombination by a region of non-homology].

Effects of a non-homology region associated with a deletion marker on recombination were studied in two-factor crosses between rII mutants of T4 phage. The basic experimental approach consisted of the comparison of a deletion with the point mutation located at one of the borders of the segment deleted in crosses against the same set of the test markers. The results obtained are in good accordance with the predictions of the model of elastic interaction of migrating cross connection with the nonhomology region. This accordance argues strongly in favour of the hybrid region propagation via branch migration in T4 recombination intermediates.

Crossing Over, Genetic↗