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1.
Bioconjug Chem ; 29(12): 4127-4139, 2018 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-30525485

RESUMEN

Antimicrobial peptides (AMPs) exhibit a wide spectrum of actions, ranging from a direct bactericidal effect to multifunctional activities as immune effector molecules. The aim of this study was to examine the anti-inflammatory properties of a DAL-PEG-DK5 conjugate composed of a lysine-rich derivative of amphibian temporin-1CEb (DK5) and dalargin (DAL), the synthetic Leu-enkephalin analogue. Detailed study of the endotoxin-neutralizing activity of the peptide revealed that DAL-PEG-DK5 interacts with LPS and the LPS binding protein (LBP). Moreover, DAL-PEG-DK5 prevented dimerization of TLR4 at the macrophage surface upon LPS stimulation. This inhibited activation of the NF-κB signaling pathway and markedly reduced pro-inflammatory cytokine production. Finally, we showed that aggregation of DAL-PEG-DK5 into amyloid-like structures induced by LPS neutralized the endotoxin proinflammatory activity. Consequently, DAL-PEG-DK5 reduced morbidity and mortality in vivo, in a mouse model of endotoxin-induced septic shock. Collectively, the data suggest that DAL-PEG-DK5 is a promising therapeutic compound for sepsis.


Asunto(s)
Encefalinas/química , Encefalinas/uso terapéutico , Péptidos/química , Péptidos/uso terapéutico , Proteínas/química , Proteínas/uso terapéutico , Sepsis/tratamiento farmacológico , Animales , Péptidos Catiónicos Antimicrobianos , Membrana Celular/metabolismo , Dimerización , Encefalinas/farmacología , Humanos , Lipopolisacáridos/metabolismo , Lipopolisacáridos/farmacología , Activación de Macrófagos/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Péptidos/farmacología , Proteínas/farmacología , Células RAW 264.7 , Transducción de Señal/efectos de los fármacos , Receptor Toll-Like 4/metabolismo
2.
Neoplasma ; 65(6): 993-997, 2018 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29940768

RESUMEN

The incorporation of pegylated asparaginase (PEG-ASP) in pediatric and adult acute lymphoblastic leukemia (ALL) protocols remains a worldwide therapeutic approach. However the safety profile remains a challenge, and herein we report the toxicity of an intravenous single dose of 1000 IU/m2 PEG-ASP administered in remission induction for adult ALL patients. Thirty-two patients at median diagnostic age of 32 years (median of 19-65) were included in this analysis. Most patients had B-cell lymphoblastic leukemia (n=26; 78%) and 81% of cases were <55 years at study entry. 75% of patients had <30x109/l leukocyte count at diagnosis and median follow-up was 14 months (range 0.8-69). All grade 3/4 adverse events (AEs) after PEG-ASP administration were observed in 24 patients (75%). The most common grade 3/4 AEs were: decreased fibrinogen (58%), increased bilirubin (31%) and increased GGTP (27%). Clinical manifestations related to PEG-ASP were seen in 9 patients and included: abdominal pain (n=6), thrombosis (n=2), diarrhea (n=1) and pancreatitis (n=1). The median time from PEG-ASP administration to first toxic symptoms was 7 days (range 1-19), and there were also 4 (13%) early induction deaths. All deaths were observed in ≥50-year-old patients after a median of 5 days following PEG-ASP (range 1-9). Three of these four patients had massive obesity. While all expired patients had grade 4 neutropenia and thrombocytopenia at the time of death, sepsis was not present. Administration of PEG-ASP in induction remission for ALL patients resulted in a significant, but mostly reversible hepatotoxicity. This PEG-ASP treatment should be administered with caution for older, obese patients.


Asunto(s)
Antineoplásicos/uso terapéutico , Asparaginasa/uso terapéutico , Polietilenglicoles/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica , Humanos , Persona de Mediana Edad , Inducción de Remisión , Adulto Joven
3.
Sci Rep ; 14(1): 13185, 2024 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-38851838

RESUMEN

Delivery of active protein especially enzyme is one of the major therapeutic challenge. Replacing or substituted invalid/improper acting protein offer fast and effective treatment of disease. Herein, we describe the synthesis and properties of biotinylated peptidomimetics consisting of oxoacid-modified 2,3, L-diaminopropionic acid residues with guanidine groups on its side chains. Electrophoretic analysis showed that the obtained compounds interact with FITC-labeled streptavidin or a streptavidin-ß-galactosidase hybrid in an efficient manner. Complexes formed by the abovementioned molecules are able to cross the cell membranes of cancer or healthy cells and show promising compatibility with live cells. Analysis of ß-galactosidase activity inside the cells revealed surprisingly high levels of active enzyme in complex-treated cells compared to controls. This observation was confirmed by immunochemical studies in which the presence of ß-galactosidase was detected in the membrane and vesicles of the cells.


Asunto(s)
beta-Alanina , beta-Galactosidasa , Humanos , beta-Alanina/análogos & derivados , beta-Alanina/química , beta-Alanina/metabolismo , beta-Galactosidasa/metabolismo , Polímeros/química , Peptidomiméticos/química , Estreptavidina/química , Estreptavidina/metabolismo , Membrana Celular/metabolismo
4.
Anal Biochem ; 442(1): 75-82, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-23911525

RESUMEN

We report the synthesis and enzymatic studies on a new proteinase 3 intermolecular quenched substrate with enhanced selectivity over neutrophil elastase. Using combinatorial chemistry methods, we were able to synthesize the hexapeptide library with the general formula ABZ-Tyr-Tyr-Abu-X1'-X2'-X3'-Tyr(3-NO2)-NH2 using the mix and split method. The iterative deconvolution of such a library allowed us to obtain the sequence ABZ-Tyr-Tyr-Abu-Asn-Glu-Pro-Tyr(3-NO2)-NH2 with a high specificity constant (kcat/KM=1534×10(3)M(-1)s(-1)) and superior selectivity over neutrophil elastase and other neutrophil-derived serine proteases. Moreover, using the obtained substrate, we were able to detect a picomolar concentration of proteinase 3 (PR3). Incubation of the above-mentioned substrate with neutrophil lysate resulted in a strong fluorescent signal that was significantly reduced in the presence of a PR3 selective inhibitor.


Asunto(s)
Elastasa de Leucocito/metabolismo , Mieloblastina/metabolismo , Oligopéptidos/síntesis química , Oligopéptidos/metabolismo , Técnicas Químicas Combinatorias , Humanos , Oligopéptidos/química , Especificidad por Sustrato
5.
Biopolymers ; 100(2): 154-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23616099

RESUMEN

A series of compounds containing either non-proteinogenic ß-/γ-amino acids or N-substituted ß-alanine residues (ß-peptoid units) in P1 specificity position were synthesized based on the structure of sunflower trypsin inhibitor 1 (SFTI-1). The compounds were synthesized on a solid support; the N-substituted ß-alanines (ßNhlys and ßNhphe) were introduced into a peptidomimetic chain via a two-step approach using acryloyl chloride and an appropriate primary amine. The inhibitory activities were characterized in vitro against bovine α-chymotrypsin or bovine ß-trypsin. Three analogues displayed activity comparable to fully proteinogenic counterparts-monocyclic SFTI-1 and [Phe(5)]SFTI-1. Moreover, all active peptidomimetics were resistant toward proteolytic degradation, even after 24-h incubation at room temperature.


Asunto(s)
Aminoácidos , beta-Alanina , Aminoácidos/química , Animales , Peptoides , Tripsina/química , Inhibidores de Tripsina/química
6.
J Exp Med ; 188(9): 1603-10, 1998 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-9802972

RESUMEN

Recombinant interleukin 12 (IL-12) can profoundly suppress cellular immune responses in mice. To define the underlying mechanism, recombinant murine (rm)IL-12 was given to C57BL/6 mice undergoing alloimmunization and found to transiently but profoundly suppress in vivo and in vitro allogeneic responses and in vitro splenocyte mitogenic responses. Use of neutralizing antibodies and genetically deficient mice showed that IFN-gamma (but not TNF-alpha) mediated rmIL-12-induced immune suppression. Splenocyte fractionation studies revealed that adherent cells from rmIL-12-treated mice suppressed the mitogenic response of normal nonadherent cells to concanavalin A and IL-2. Addition of an inhibitor of nitric oxide synthase (NOS) restored mitogenic responses, and inducible (i)NOS-/- mice were not immunosuppressed by rmIL-12. These results support the view that suppression of T cell responses is due to NO produced by macrophages responding to the high levels of IFN-gamma induced by rmIL-12. When a NOS inhibitor was given with rmIL-12 during vaccination of A/J mice with irradiated SCK tumor cells, immunosuppression was averted and the extent of rmIL-12's ability to enhance induction of protective antitumor immunity was revealed. This demonstrates that rmIL-12 is an effective vaccine adjuvant whose efficacy may be masked by its transient immunosuppressive effect.


Asunto(s)
Tolerancia Inmunológica/efectos de los fármacos , Interferón gamma/metabolismo , Interleucina-12/farmacología , Óxido Nítrico Sintasa/biosíntesis , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/farmacología , Animales , Inducción Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Femenino , Inmunosupresores/administración & dosificación , Inmunosupresores/farmacología , Interferón gamma/genética , Interleucina-12/administración & dosificación , Activación de Linfocitos/efectos de los fármacos , Ratones , Ratones Endogámicos A , Ratones Endogámicos C57BL , Ratones Noqueados , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico/inmunología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa de Tipo II , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacología , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Vacunas/administración & dosificación
7.
J Exp Med ; 180(3): 907-15, 1994 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-7914909

RESUMEN

The Shwartzman reaction is elicited by two injections of lipopolysaccharide (LPS) in mice. The priming LPS injection is given in the footpad, whereas the lethal LPS challenge is given intravenously 24 h later. The injection of interferon gamma (IFN-gamma) or interleukin 12 (IL-12) instead of the LPS priming injection induced the lethal reaction in mice further challenged with LPS. Antibodies against IFN-gamma when given together with the priming agent, prevented the lethal reaction in mice primed with either LPS, IL-12, or IFN-gamma. Antibodies against IL-12, when given together with the priming agent, prevented the lethal reaction in mice primed with either LPS or IL-12 but not with IFN-gamma. These results strongly suggest that LPS induces the release of IL-12, that IL-12 induces the production of IFN-gamma, and that IFN-gamma is the cytokine that primes macrophages and other cell types. Upon LPS challenge, the lethal Shwartzman reaction is induced by a massive production of inflammatory cytokines that act on the target sites already sensitized by IFN-gamma. If mixtures of TNF and IL-1 or mixtures of TNF and IFN-gamma are used to challenge mice previously primed with IFN-gamma or IL-12, mortality is induced. In the same conditions, the individual cytokines or a mixture of IL-1 and IFN-gamma do not replace the LPS challenge. When the mice are primed with LPS, the combination of TNF, IL-1, and IFN-gamma induced only a partial mortality incidence suggesting that the involvement of other LPS-induced factors.


Asunto(s)
Interferón gamma/fisiología , Interleucinas/fisiología , Fenómeno de Shwartzman/etiología , Factor de Necrosis Tumoral alfa/fisiología , Animales , Anticuerpos Monoclonales/inmunología , Femenino , Interferón gamma/toxicidad , Interleucina-1/biosíntesis , Interleucina-12 , Interleucina-6/biosíntesis , Interleucinas/toxicidad , Lipopolisacáridos/toxicidad , Ratones , Ratas , Factor de Necrosis Tumoral alfa/toxicidad
8.
J Exp Med ; 180(1): 223-31, 1994 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-7516409

RESUMEN

We have previously shown that dendritic cells isolated after overnight culture, which can express B7 and are potent stimulators of naive T cell proliferation, are relatively poor at inducing the proliferation of a panel of murine T helper 1 (Th1) clones. Maximal stimulation of Th1 clones was achieved using unseparated splenic antigen presenting cells (APC). An explanation for these findings is provided in the present study where we show that FcR+ L cells transfected with B7 stimulate minimal proliferation of Th1 clones in response to anti-CD3 antibodies, in contrast to induction of significant proliferation of naive T cells. However, addition of interleukin 12 (IL-12) to cultures of Th1 cells stimulated with anti-CD3 and FcR+ B7 transfectants resulted in a very pronounced increase in proliferation and interferon gamma (IFN-gamma) production. Exogenous IL-12 did not affect the B7-induced proliferation of naive T cells. This showed that whereas costimulatory signals delivered via B7-CD28 interaction are sufficient to induce significant proliferation of naive T cells activated through occupancy of the T cell receptor, Th1 T cell clones require cooperative costimulation by B7 and IL-12. This costimulation was shown to be specific by inhibition of proliferation and IFN-gamma production using chimeric soluble cytolytic T lymphocyte-associated antigen 4-human IgG1Fc (CTLA4-Ig) and anti-IL-12 antibodies. Furthermore, the significant antigen specific proliferation and IFN-gamma production by Th1 clones observed when splenocytes were used as APC was almost completely abrogated using CTLA4-Ig and anti-IL-12 antibodies. Thus two costimulatory signals, B7 and IL-12, account for the ability of splenic APC to induce maximal stimulation of Th1 clones. IL-10 downregulates the expression of IL-12 by IFN-gamma-stimulated macrophages and this may account largely for t the ability of IL-10 to inhibit APC function of splenic and macrophage APC for the induction of Th1 cell proliferation and IFN-gamma production. Indeed we show that IL-12 can overcome the inhibitory effect of IL-10 for the APC-dependent induction of proliferation and IFN-gamma production by Th1 clones. These results suggest that proliferation by terminally differentiated Th1 clones, in contrast to naive T cells, requires stimulation via membrane-bound B7 and a cytokine, IL-12. It is possible that these signals may result in the activation of unresponsive T cells during an inflammatory response. IL-10, by its role in regulating such innate inflammatory responses, may thus help to maintain these T cells in an unresponsive state.


Asunto(s)
Antígeno B7-1/fisiología , Inmunoconjugados , Interferón gamma/biosíntesis , Interleucinas/fisiología , Activación de Linfocitos , Linfocitos T Colaboradores-Inductores/fisiología , Abatacept , Animales , Células Presentadoras de Antígenos/fisiología , Antígenos CD , Antígenos de Diferenciación/fisiología , Secuencia de Bases , Antígeno CTLA-4 , Línea Celular , Células Clonales , Femenino , Interleucina-10/farmacología , Interleucina-12 , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Datos de Secuencia Molecular
9.
Bioorg Med Chem ; 18(15): 5504-9, 2010 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-20620066

RESUMEN

Human airway trypsin-like protease (HAT), also referred to as TMPRSS11D, is an important physiological enzyme with the main activity pronounced in an airway. In this work we have described the substrate specificity and selectivity study of the protease, performed by the combinatorial approach. Fluorogenic/chromogenic tetrapeptide library was used for this purpose. The most efficiently hydrolyzed substrates' sequences that we selected were ABZ-Arg-Gln-Asp-Arg(Lys)-ANB-NH(2). The most active inhibitor with C-terminal Arg residue underwent detectable proteolysis action in the presence of 35pM of HAT. Based on the selected sequences the two peptide aldehydes were synthesized and (Abz-Arg-Gln-Asp-Arg(Lys)-H) were found to be an effective HAT inhibitor, working in nanomolar range with inhibition constant 54nM and 112nM, respectively.


Asunto(s)
Péptidos/química , Serina Endopeptidasas/química , Inhibidores de Serina Proteinasa/química , Secuencia de Aminoácidos , Técnicas Químicas Combinatorias , Transferencia Resonante de Energía de Fluorescencia , Colorantes Fluorescentes/química , Humanos , Cinética , Biblioteca de Péptidos , Péptidos/síntesis química , Péptidos/farmacología , Serina Endopeptidasas/metabolismo , Inhibidores de Serina Proteinasa/síntesis química , Inhibidores de Serina Proteinasa/farmacología , Especificidad por Sustrato
11.
Science ; 263(5144): 235-7, 1994 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-7904381

RESUMEN

Protection induced by vaccination depends on the capacity of the vaccine to elicit an appropriate immune response. In leishmaniasis, protection requires leishmanial-specific CD4+ T helper (TH) cells. Vaccination of BALB/c mice with leishmanial antigens and interleukin-12 (IL-12) promoted the development of leishmanial-specific CD4+ TH1 cells. These mice were resistant to subsequent infection with Leishmania major. Thus, IL-12 is an effective adjuvant for the initiation of protective cell-mediated immunity against leishmaniasis and may be an important component in other vaccines that need to induce cell-mediated immunity.


Asunto(s)
Adyuvantes Inmunológicos , Interleucinas/inmunología , Leishmania major/inmunología , Leishmaniasis Cutánea/prevención & control , Vacunas Antiprotozoos/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Antígenos de Protozoos/inmunología , Citotoxicidad Inmunológica , Interferón gamma/biosíntesis , Interleucina-12 , Interleucina-4/biosíntesis , Células Asesinas Naturales/inmunología , Leishmaniasis Cutánea/inmunología , Ganglios Linfáticos/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Bazo/inmunología
12.
Science ; 273(5272): 228-31, 1996 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-8662504

RESUMEN

The mechanisms underlying the profound suppression of cell-mediated immunity (CMI) accompanying measles are unclear. Interleukin-12 (IL-12), derived principally from monocytes and macrophages, is critical for the generation of CMI. Measles virus (MV) infection of primary human monocytes specifically down-regulated IL-12 production. Cross-linking of CD46, a complement regulatory protein that is the cellular receptor for MV, with antibody or with the complement activation product C3b similarly inhibited monocyte IL-12 production, providing a plausible mechanism for MV-induced immunosuppression. CD46 provides a regulatory link between the complement system and cellular immune responses.


Asunto(s)
Antígenos CD/fisiología , Tolerancia Inmunológica , Interleucina-12/biosíntesis , Virus del Sarampión/inmunología , Glicoproteínas de Membrana/fisiología , Monocitos/inmunología , Monocitos/virología , Receptores Virales/fisiología , Anticuerpos Monoclonales , Antígenos CD/inmunología , Sitios de Unión , Células Cultivadas , Quimiocinas/biosíntesis , Complemento C3b/inmunología , Complemento C3b/fisiología , Citocinas/biosíntesis , Regulación hacia Abajo , Humanos , Interleucina-10/fisiología , Virus del Sarampión/metabolismo , Proteína Cofactora de Membrana , Glicoproteínas de Membrana/inmunología , Receptores Virales/inmunología
13.
Eur Rev Med Pharmacol Sci ; 22(21): 7379-7384, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30468484

RESUMEN

OBJECTIVE: Scarce clinical and experimental studies suggest that hepcidin can be a protein participating in the development of metabolic disorders, while its synthesis and concentration in the circulation outside of the iron metabolism parameters can be influenced by hormones. The aim of the present study was to determine the correlation between the concentration of hepcidin in serum and the occurrence of insulin resistance and hyperandrogenemia in women with PCOS. PATIENTS AND METHODS: Five groups of women with PCOS were divided based on: correct body mass (17 without hyperandrogenemia and insulin resistance - G1; 17 with hyperandrogenemia and without insulin resistance - G2; 11 without hyperandrogenemia and with insulin resistance - G3; 10 with hyperandrogenemia and insulin resistance - G4), metabolic and hormonal parameters and selected markers of iron metabolism. RESULTS: Serum glucose levels were significantly higher in the group G3 than G1 and in the group G4 than G1 and G2. Serum insulin levels and HOMA-IR values were significantly higher in the groups G3 and G4 than G1 and G2. Serum androstenedione levels were significantly higher in the group G2 than G1 and G3 than G2. Serum transferrin levels were significantly lower in the group G1 than in the reaming study groups. CONCLUSIONS: It has been demonstrated that insulin resistance and hyperandrogenemia appear to be the factors decreasing the concentration of transferrin circulation, but not the remaining parameters of the iron metabolism in the studied women. No relationship between the concentration of hepcidin circulation and other studied parameters of the iron metabolism and the parameters of the carbohydrate metabolism was discovered. Androstenedione can stimulate hepcidin synthesis in women with PCOS with correct body mass.


Asunto(s)
Hepcidinas/sangre , Hiperandrogenismo/sangre , Hiperandrogenismo/epidemiología , Resistencia a la Insulina , Síndrome del Ovario Poliquístico/sangre , Síndrome del Ovario Poliquístico/complicaciones , Adolescente , Adulto , Glucemia/análisis , Índice de Masa Corporal , Femenino , Humanos , Hierro/metabolismo , Transferrina/análisis , Adulto Joven
14.
Eur Rev Med Pharmacol Sci ; 22(11): 3586-3594, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29917213

RESUMEN

OBJECTIVE: The first report concerning methotrexate (MTX) in the treatment of Mycosis fungoides (MF) was published in 1964 by Wright. The mechanism of MTX action in the treatment of primary cutaneous T-cell lymphoma (CTCL) has been not explained in detail yet (the anti-inflammatory, immunomodulating, immunosuppressive, and cytostatic actions have been under discussion). PATIENTS AND METHODS: This is a retrospective analysis of 79 MF patients in 4 dermatology clinical centers in Poland. Data are presented in terms of the duration, use of MTX, the effectiveness of treatment with MTX in terms of time required to achieve remission, the disease stage, route of administration, age at diagnosis and the dosage. Moreover, the occurrence of side effects depending on the route of administration and duration of therapy with MTX was analyzed. RESULTS: The analysis has revealed that 56 patients (70,9%) had achieved remission on the MTX. The remission began in the 1st month of therapy in 20% of patients, lasted 4 to 6 months in 50% of cases. At least 12 months' remission was confirmed in 25% of patients (2-year-long only in 10% and 3-year-long in 5% of patients). The time to remission was related to the stage of disease at diagnosis as well as to minimal and maximal dose of MTX. The total therapeutic dose of MTX was found important for the course of the disease: higher total dose had prolonged the remission. CONCLUSIONS: Despite the common use of MTX in MF patients, relatively few clinical studies have been published. The response of MF subjects to MTX seems to depend on the stage and, more importantly, the dose of MTX treatment. Methotrexate appears to be an effective treatment at every stage of MF; however, it is not devoided of side effects such as infections and elevated level of aminotransferases, which are most common.


Asunto(s)
Inmunosupresores/uso terapéutico , Metotrexato/uso terapéutico , Micosis Fungoide/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Micosis Fungoide/mortalidad , Micosis Fungoide/patología , Polonia , Inducción de Remisión , Estudios Retrospectivos , Resultado del Tratamiento
15.
J Clin Invest ; 101(6): 1441-52, 1998 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-9502787

RESUMEN

The antitumor effect and mechanisms activated by murine IL-12 and IL-18, cytokines that induce IFN-gamma production, were studied using engineered SCK murine mammary carcinoma cells. In syngeneic A/J mice, SCK cells expressing mIL-12 or mIL-18 were less tumorigenic and formed tumors more slowly than control cells. Neither SCK.12 nor SCK.18 cells protected significantly against tumorigenesis by distant SCK cells. However, inoculation of the two cell types together synergistically protected 70% of mice from concurrently injected distant SCK cells and 30% of mice from SCK cells established 3 d earlier. Antibody neutralization studies revealed that the antitumor effects of secreted mIL-12 and mIL-18 required IFN-gamma. Interestingly, half the survivors of SCK.12 and/or SCK.18 cells developed protective immunity suggesting that anti-SCK immunity is unlikely to be responsible for protection. Instead, angiogenesis inhibition, assayed by Matrigel implants, appeared to be a property of both SCK.12 and SCK.18 cells and the two cell types together produced significantly greater systemic inhibition of angiogenesis. This suggests that inhibition of tumor angiogenesis is an important part of the systemic antitumor effect produced by mIL-12 and mIL-18.


Asunto(s)
Citocinas/inmunología , Interleucina-12/inmunología , Neoplasias Experimentales/irrigación sanguínea , Neoplasias Experimentales/inmunología , Neovascularización Patológica/inmunología , Animales , Anticuerpos Bloqueadores/inmunología , Citocinas/genética , Citocinas/metabolismo , Pruebas Inmunológicas de Citotoxicidad , Femenino , Expresión Génica , Vectores Genéticos , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucina-12/genética , Interleucina-12/metabolismo , Interleucina-18 , Ratones , Ratones SCID , Trasplante de Neoplasias/inmunología , Neoplasias Experimentales/patología , Neovascularización Patológica/patología , Pruebas de Neutralización , Bazo/citología , Bazo/inmunología , Transducción Genética , Células Tumorales Cultivadas/metabolismo
16.
Radiat Prot Dosimetry ; 177(1-2): 164-167, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29036377

RESUMEN

The article presents the advantages of the radon chamber with volume of 17 m3, that belongs to Silesian Centre for Environmental Radioactivity and its applicability for calibration of equipment designed to measure the radon concentration and its short-lived decay products. The chamber can be operated under controlled conditions in the range from -20 to 60°C and relative humidity from 20 to 90%. There is also discussed the influence of aerosol concentration and their size distribution on the calibration results. When calibrating the measuring devices in an atmosphere with a large contribution of ultrafine particles that are defined as particles with diameter <0.1 µm, their sensitivity may decrease by tens of percent.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Minería , Exposición Profesional/análisis , Monitoreo de Radiación/instrumentación , Radón/análisis , Calibración , Diseño de Equipo , Humanos , Tamaño de la Partícula , Polonia , Hijas del Radón/análisis
17.
Radiat Prot Dosimetry ; 177(1-2): 45-48, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29036704

RESUMEN

Liquid scintillation counting (LSC) is a measuring technique, broadly applied in environmental monitoring of radionuclides. One of the possible applications of LSC is the measurement of radon and thoron decay products. But this method is suitable only for grab sampling. For long-term measurements a different technique can be applied-monitors of potential alpha energy concentration (PAEC) with thermoluminescent detectors (TLD). In these devices, called Alfa-2000 sampling probe, TL detectors (CaSO4:Dy) are applied for alpha particles counting. Three independent heads are placed over the membrane filter in a dust sampler's microcyclone. Such solution enables simultaneous measurements of PAEC and dust content. Moreover, the information which is stored in TLD chips is the energy of alpha particles, not the number of counted particles. Therefore, the readout of TL detector shows directly potential alpha energy, with no dependence on equilibrium factor, etc. This technique, which had been used only for radon decay products measurements, was modified by author to allow simultaneous measurements of radon and thoron PAEC. The LSC method can be used for calibration of portable radon decay products monitors. The LSC method has the advantage to be an absolute one, the TLD method to measure directly the (dose relevant) deposited energy.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Contaminación del Aire Interior/análisis , Monitoreo de Radiación/instrumentación , Hijas del Radón/análisis , Radón/análisis , Conteo por Cintilación/métodos , Dosimetría Termoluminiscente/métodos , Partículas alfa , Calibración , Polvo
18.
Cancer Res ; 57(12): 2460-7, 1997 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-9192826

RESUMEN

Use of the cytokine interleukin 12 (IL-12) has been shown to enhance the rejection of a variety of murine tumors, but preclinical and clinical studies have revealed that recombinant IL-12 (rlL-12) can produce severe toxicity. In an effort to improve the tolerance and therapeutic effectiveness of this cytokine, we investigated the influence of giving a single dose of recombinant murine IL-12 (rmIL-12) a week prior to daily cytokine administration (predosing) on its toxic and antitumor effects. These studies were performed in C3H/HeN mice, in which a course of rmIL-12 at standard doses without predosing induced rejection of syngeneic K1735 melanomas in 33%, and in A/J mice, in which treatment induced rejection of syngeneic B7-1+ SCK (SCK.B7-1) mammary carcinomas in 63%. Administration of a predose of rmIL-12 markedly reduced cytokine toxicity in a dose-dependent manner and allowed safe administration of up to 8-fold higher doses of daily rmIL-12 in C3H/HeN mice and 4-fold higher doses of rmIL-12 in A/J mice. Predosing followed by either standard or high daily doses of rmIL-12 did not significantly alter most end points of rmIL-12 treatment of K1735 or SCK.B7-1 tumors (survival, death from tumor, development of protective immunity, and so on), but they appeared to attenuate early control of tumorigenesis by rmIL-12. Evidence for the latter comes from a shortening of the characteristic rmIL-12-induced delay in tumor appearance and in the frequent appearance of tumors that subsequently regress. However, higher doses appear to produce better therapeutic results than standard doses of rmIL-12 after predosing. Predosing severely blunted induction of serum IFN-gamma levels by rmIL-12, which probably accounts for many of the effects of predosing on rmIL-12 toxicity and efficacy. Thus, predosing desensitizes mice to the toxic effects of rIL-12 and allows much higher doses to be given but, despite this, it does not improve and, by some criteria, it attenuates rIL-12 therapeutic outcome. Our results do not support the use of predosing as a way to enhance the effectiveness of rIL-12 in cancer clinical trials.


Asunto(s)
Antineoplásicos/toxicidad , Interleucina-12/administración & dosificación , Interleucina-12/toxicidad , Proteínas Recombinantes/administración & dosificación , Animales , Antineoplásicos/administración & dosificación , Femenino , Interferón gamma/sangre , Interleucina-12/sangre , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Melanoma/tratamiento farmacológico , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos , Trasplante de Neoplasias , Proteínas Recombinantes/sangre , Proteínas Recombinantes/toxicidad , Células Tumorales Cultivadas
19.
Cancer Res ; 55(21): 4980-7, 1995 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-7585539

RESUMEN

Enhanced host rejection of tumor cells is the primary goal of cancer immunotherapy and, in many murine tumor models, has been accomplished by engineering cells to express B7 costimulatory molecules or creating an environment rich in certain cytokines. We examined the effect of tumor cell B7-1 expression and administered recombinant interleukin 12 (IL-12) on the syngeneic host response to rapidly growing, poorly immunogenic SCK mammary carcinoma cells and to more slowly growing, immunogenic K1735 melanoma cells. Whereas B7-1 expression induced rejection of K1735 cells in 78% of mice, and IL-12 induced rejection in 38%, B7-1 expression induced rejection of SCK cells in only 28% of mice, and IL-12 induced rejection in none. The relative ineffectiveness of either B7-1 or IL-12 alone to induce rejection of SCK cells led us to combine the two manipulations. This resulted in rejection of SCK cells in 74% of mice and dramatically delayed tumor development in the remainder. Tumor rechallenge studies indicated that the surviving mice developed specific immunity to wild-type SCK cells. Lymphocyte subset ablation and IFN-gamma depletion studies indicated that rejection of SCK tumor cells brought about by the synergistic effects of B7-1 and IL-12 is mediated by a rapidly developing, systemic antitumor immune response that is dependent on the presence of both CD8+ and CD4+ T cells and involves IFN-gamma. Additionally, the synergistic effect of B7-1 expression and IL-12 administration is capable of inducing rejection of control SCK tumors simultaneously established in the opposite flank. The efficacy of B7-1 and IL-12 in inducing protective immunity against a poorly immunogenic, aggressive murine tumor indicates that this combination is particularly effective at producing a potent antitumor immune response that may be of therapeutic benefit.


Asunto(s)
Antígeno B7-1/uso terapéutico , Interleucina-12/uso terapéutico , Neoplasias Mamarias Experimentales/inmunología , Neoplasias Mamarias Experimentales/prevención & control , Melanoma Experimental/inmunología , Melanoma Experimental/prevención & control , Trasplante de Neoplasias/inmunología , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Sinergismo Farmacológico , Femenino , Rechazo de Injerto/inmunología , Inmunidad Innata , Inmunoterapia , Interferón gamma/biosíntesis , Neoplasias Mamarias Experimentales/terapia , Ratones , Ratones Endogámicos A , Ratones Endogámicos C3H , Sensibilidad y Especificidad
20.
Cancer Res ; 58(3): 491-9, 1998 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-9458095

RESUMEN

Adjuvant use of recombinant murine IL-12 (rmIL-12) was examined in mice vaccinated with irradiated syngeneic tumor or allogeneic cells. rmIL-12 given to A/J mice vaccinated with irradiated SCK tumor cells engineered to secrete granulocyte/macrophage-colony-stimulating factor resulted in significantly better protection from tumor challenges 28 days after vaccination but, unexpectedly, severely compromised host protection 14 days after vaccination. Immune suppression was rmIL-12 dose dependent and manifested as reduced splenic CTL activity, stimulated cytokine release and ability to reject SCK cells. Transient immune suppression was also seen with rmIL-12 given during vaccination of C3H/HeN mice with irradiated K1735 melanoma cells and of C57BL/6 mice with irradiated allogeneic HKB cells. The period of suppression coincided with transiently reduced splenic T-cell mitogenic responses to concanavalin A and IL-2, suggesting that they may be causally related. Suppression appears to be due to impaired immune effector mechanisms rather than impaired host immunization, which is actually enhanced as evidenced by the enhanced reaction to immunogens when hosts are challenged later after rmIL-12 administration. Demonstration that rmIL-12, as it is frequently used, induces a transient period of impaired immune response that can compromise host protection suggests that the unquestioned effectiveness of rmIL-12 against murine tumors is primarily due to activation of mechanisms other than antigen-specific tumor immunity (e.g., antiangiogenic effects) and that use of human IL-12 should be monitored for similar effects.


Asunto(s)
Inmunidad Celular/efectos de los fármacos , Terapia de Inmunosupresión , Interleucina-12/farmacología , Vacunación , Animales , Vacunas contra el Cáncer/inmunología , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Interferón gamma/metabolismo , Interleucina-4/metabolismo , Ganglios Linfáticos/inmunología , Neoplasias Mamarias Experimentales/inmunología , Neoplasias Mamarias Experimentales/prevención & control , Melanoma Experimental/inmunología , Melanoma Experimental/prevención & control , Ratones , Ratones Endogámicos A , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Trasplante de Neoplasias/inmunología , Proteínas Recombinantes de Fusión/farmacología , Especificidad de la Especie , Bazo/inmunología , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/inmunología , Factores de Tiempo
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