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1.
Animal ; 6(6): 902-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22558960

RESUMO

The effects of dietary nucleotide supplementation from 9 days of age until the end of post-weaning on piglets hormonal and immune responses and on growth performance were investigated. During lactation (days 9 to 21) and post-weaning (days 22 to 55) 10 [HBI Fomeva11 × (Large White × Landrace)] litters (n = 108 piglets) had ad libitum access to two standard diets, both supplemented with 0% (T0 group) or 0.1% (T1 group) of yeast extract nucleotides. BW of piglets at days 21 (P < 0.10), 35 and 55 (P < 0.05) was greater in T1 compared with T0. Feed intake was not different between groups (P > 0.05). Cortisol content was lower in T1 than in T0 at days 28 and 35 (P < 0.05), whereas growth hormone was lower at day 35 (P < 0.05). Levels of IGF-1 were similar across groups (P > 0.05). Nucleotide-supplemented diets increased lymphocyte subpopulation CD4-CD8+high at days 21 and 35 (P < 0.05), whereas CD4+CD8- cells were higher in T1 than in T0 at day 21 (P < 0.05). Peripheral blood mononuclear cells cytokine expression was influenced by dietary nucleotide supplementation. At weaning, interleukin (IL)-6 and IL-1ß expression was lower (P < 0.05) in T1 compared with T0, whereas the expression of interferon (IFN)-γ and IL-10 was higher (P < 0.05). At day 28, piglets in T1 showed higher values of tumor necrosis factor (TNF)-α expression than T0 and lower values of IL-10 expression (P < 0.05). Dietary nucleotide supplementation had a suppressive effect on IL-6 and IL-10 expression (P < 0.05) at day 35. On the contrary, the expression of IFN-γ, TNF-α and IL-1ß was enhanced (P < 0.05). In conclusion, these results suggest that starting a dietary nucleotide supplementation before weaning can improve the adaptive capabilities of weaned piglets to the stressors, enhancing the growth performance.


Assuntos
Criação de Animais Domésticos , Animais Lactentes/crescimento & desenvolvimento , Suplementos Nutricionais/análise , Nucleotídeos/administração & dosagem , Sus scrofa/crescimento & desenvolvimento , Leveduras/química , Ração Animal/análise , Animais , Animais Lactentes/imunologia , Animais Lactentes/fisiologia , Feminino , Expressão Gênica , Hormônio do Crescimento/sangue , Hidrocortisona/sangue , Fator de Crescimento Insulin-Like I/análise , Interferon gama/sangue , Interferon gama/metabolismo , Interleucinas/sangue , Interleucinas/metabolismo , Lactação , Masculino , Sus scrofa/imunologia , Sus scrofa/fisiologia , Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismo , Desmame
2.
Neurology ; 55(8): 1207-9, 2000 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-11071501

RESUMO

The authors prospectively studied the natural course of cardiac involvement and its relationship to cytosine-thymine-guanine (CTG) expansion in 50 patients with myotonic dystrophy who were submitted to periodic cardiovascular EKG and EKG-Holter monitoring during a median follow-up of 56 months. Nineteen patients (38%) developed major EKG changes. CTG length was not correlated with the frequency of EKG abnormalities, but was inversely correlated with the age at onset of EKG abnormalities (p < 0.0001). CTG length influences the timing of cardiac complications in myotonic dystrophy.


Assuntos
Cardiopatias/genética , Cardiopatias/fisiopatologia , Distrofia Miotônica/genética , Repetições de Trinucleotídeos/genética , Adolescente , Adulto , Idade de Início , Criança , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
4.
Neuromuscul Disord ; 9(4): 215-9, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10399747

RESUMO

Myotonic dystrophy (DM) is a multisystemic disease caused by expansion of a CTG trinucleotide repeat in the 3' untranslated region of the DMPK protein kinase gene on chromosome 19q13.3. The mechanism by which this expansion causes disease remains unknown. It has been suggested that CTG expansion not only affects the expression of the DMPK gene, but also alters the nuclear RNA metabolism and expression of neighboring genes. DMAHP, which is expressed in various human tissues, including skeletal muscle, heart and brain, is immediately distal to the 3' end of DMPK gene, in a CpG island which contains the CTG repeat. Here we report a 4- to 5-fold reduction of the expression of the DMAHP gene in different brain areas of DM patients. Our results demonstrate that [CTG]n expansion alters the brain DMAHP mRNA expression supporting a dominant-negative effect at the cellular level of DM [CTG]n mutation. The reduced brain expression of DMAHP could explain cerebral impairment in DM patients.


Assuntos
Química Encefálica/fisiologia , Proteínas de Homeodomínio/biossíntese , Distrofia Miotônica/metabolismo , RNA Mensageiro/biossíntese , Química Encefálica/genética , DNA/química , DNA/isolamento & purificação , Primers do DNA , Proteínas de Homeodomínio/genética , Humanos , Masculino , Pessoa de Meia-Idade , Distrofia Miotônica/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Biochim Biophys Acta ; 1419(2): 186-94, 1999 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10407070

RESUMO

We evaluated the transfection efficiency of five different cationic liposome/plasmid DNA complexes, during the in vitro gene transfer into human epithelial tracheal cell lines. A dramatic correlation between the transfection efficiency and the charge ratio (positive charge of liposome to negative charge of DNA) has been found. DC-Chol-DOPE was found to be the most effective liposome formulation. Therefore, a morphological and structural analysis of DC-Chol-DOPE liposomes and DC-Chol-DOPE/DNA complexes, has been performed by transmission electron microscopy (TEM) and by confocal laser scanning microscopy (CLSM), respectively. The process of interaction between DC-Chol-DOPE/DNA complexes and human epithelial tracheal cells has been studied by CLSM. These results raise some issues for in vivo gene therapy.


Assuntos
Colesterol/análogos & derivados , DNA/química , Compostos Orgânicos , Fosfatidiletanolaminas/química , Transfecção/métodos , Benzotiazóis , Linhagem Celular Transformada , Colesterol/química , DNA/farmacologia , Diaminas , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Corantes Fluorescentes , Terapia Genética , Humanos , Lipossomos/ultraestrutura , Microscopia Confocal , Microscopia Eletrônica , Quinolinas , Traqueia/metabolismo
6.
Biochem Mol Biol Int ; 47(2): 337-44, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10205680

RESUMO

The cellular uptake and distribution of cationic liposomes Dc-Chol/DOPECFTR gene complexes were assessed by electronic and confocal laser scanner microscopy (CLSM) for the CFTR gene transfer to human adenocarcinoma and tracheal epithelial cell lines. Cationic lipid forms unilamellar and multilamellar vesicles capable of rapid and efficient transport of gene into target cells. The number of fluorescent complexes was increasing with time in cells up to 6 hours showing a punctate and homogeneous DNA distribution in the cytoplasmatic and nuclear compartments, including the nucleolus. No significant difference in the biochemical and cellular behavior was observed between the investigated system and other systems previously tested. This study adds new insights into the CFTR cationic liposome-mediated gene delivery.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Transfecção/métodos , Linhagem Celular , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Adutos de DNA/química , Técnicas de Transferência de Genes , Terapia Genética/métodos , Humanos , Lipossomos/química , Microscopia Confocal , Microscopia Eletrônica
7.
Diagn Mol Pathol ; 7(3): 135-7, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9836067

RESUMO

The myotonic dystrophy (DM) expansion varies from 50 to 4000 CTG repeats in the 3' untranslated region of the DMPK gene. Direct analysis by Southern blot, after restriction enzyme digestion of genomic DNA, is the method of choice for studying the DM mutation. A long polymerase chain reaction (PCR)-formatted protocol, which involved a single genomic in vitro amplification followed by high concentration agarose gel electrophoresis and oligo-specific hybridization, was used to amplify normal alleles and DM alleles in all examined ranges of expansion (up to 3,700 CTGs) starting from a small amount of genomic DNA (> or = 15 pg). This method is quick, sensitive, and reproducible and reduces the cost of diagnostic laboratory processing.


Assuntos
Alelos , DNA/análise , Distrofia Miotônica/genética , Reação em Cadeia da Polimerase/métodos , Expansão das Repetições de Trinucleotídeos/genética , Primers do DNA/química , Triagem de Portadores Genéticos/métodos , Humanos , Distrofia Miotônica/diagnóstico , Sensibilidade e Especificidade , Repetições de Trinucleotídeos/genética
8.
Cell Biochem Funct ; 16(2): 117-22, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9636999

RESUMO

We tested the hypothesis that the instability of the trinucleotide CTG at the myotonic dystrophy (DM) locus could be an intrinsic DNA damage recognisable by the p53 cell-cycle checkpoint system. p53 mRNA and protein levels were assayed in muscle biopsies and fibroblast cell lines of DM patients and unaffected controls. No differences in mRNA and protein levels were found between patients and controls, regardless of their expansion size. However, in the cells treated with adryamicin, p53 protein levels were comparable in DM and control cells. We conclude that the CTG trinucleotide expansion within the myotonin gene does not activate the p53 surveillance system, at least in adult tissues. The escape of trinucleotide expansion from the p53-mediated DNA repair system could explain some of the biological characteristics of genome instability.


Assuntos
Genes p53 , Genoma Humano , Proteínas Musculares/metabolismo , Distrofia Miotônica/genética , RNA Mensageiro/análise , Proteína Supressora de Tumor p53/genética , Adulto , Biópsia , Western Blotting , Linhagem Celular , Fibroblastos/metabolismo , Humanos , Repetições de Trinucleotídeos , Proteína Supressora de Tumor p53/metabolismo
9.
Biochem Mol Med ; 61(1): 102-6, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9232204

RESUMO

In order to investigate the spinal muscular atrophy (SMA) disease processes, the expression of the survival motor neuron gene (SMN) has been analyzed in human fetal tissues using RT-PCR and in situ hybridization. These studies allowed the detection of SMN RNA in all the examined tissues, with no significant variation between different developmental stages. In particular, SMN mRNA was detected in spinal cord (dorsal and ventral portions), skeletal muscle, lung, heart, kidney, liver, and spleen. Moreover, RT-PCR studies demonstrated that the expression pattern of SMN isoforms was similar to that observed in adult tissues. The present data confirm a housekeeping role for the SMN protein and may have implications on the search for early therapeutic strategies.


Assuntos
Feto/metabolismo , Neurônios Motores/metabolismo , Atrofia Muscular Espinal/embriologia , Atrofia Muscular Espinal/genética , Proteínas do Tecido Nervoso/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Humanos , Hibridização In Situ , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/química , Proteínas de Ligação a RNA , Proteínas do Complexo SMN
10.
J Chromatogr ; 512: 123-9, 1990 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-2229223

RESUMO

Neuramide, a tissue extract having antiviral action against influenza A virus and immunostimulant action, was analyzed by preparative size-exclusion high-performance liquid chromatography (HPLC) and a low-molecular-weight fraction responsible for the antiviral action was isolated after reversed-phase HPLC. Four fractions having immunostimulant activity were also isolated, as evidenced by their potentiating action in the human lymphocyte proliferation induced by phytohaemagglutinin.


Assuntos
Adjuvantes Imunológicos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos , Antivirais/isolamento & purificação , Peptídeos/análise , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Humanos , Técnicas In Vitro , Vírus da Influenza A/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Cloreto de Metileno , Peso Molecular , Peptídeos/química , Peptídeos/farmacologia , Ultrafiltração
11.
J Biol Regul Homeost Agents ; 4(1): 13-8, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2169174

RESUMO

The effects of arachidonic acid metabolites on mitogen-induced interferon (IFN)-gamma production by human peripheral blood mononuclear cells (PBMC) were examined. Both prostaglandins E2 (PGE2) and leukotrienes B4 (LTB4) were produced after macrophage activation stimulated by galactose oxidase (GO) and Staphylococcal enterotoxin B (SEB), two well known inducers of IFN-gamma. To test the involvement of PGE2 and LTB4 in IFN-gamma production, GO- and SEB-activated PBMC were treated with two inhibitors of cyclooxygenase (aspirin and indomethacin) and with an inhibitor of lipoxygenase [nordihydroguaiaretic acid (NDGA)]. The results of these experiments showed that aspirin and indomethacin cause a marked increase of IFN-gamma production by GO- and SEB-activated PBMC. On the contrary, NDGA treatment reduced IFN-gamma production induced by the same agents. Moreover, whereas the addition of exogenous PGE2 reduces IFN gamma production, the addition of exogenous LTB4 does not affect IFN-gamma production. Taken together these findings indicate that arachidonic acid metabolites, produced during mitogenic activation, are involved in the regulation of IFN-gamma production and suggest that, in our system, LTB4 exerts a positive modulating signal while PGE2 represents a negative signal.


Assuntos
Ácidos Araquidônicos/metabolismo , Interferon gama/biossíntese , Ácido 5,8,11,14-Eicosatetrainoico/farmacologia , Ácido Araquidônico , Células Cultivadas , Inibidores de Ciclo-Oxigenase , Dinoprostona/farmacologia , Enterotoxinas/farmacologia , Galactose Oxidase/farmacologia , Humanos , Técnicas In Vitro , Indicadores e Reagentes , Indometacina/farmacologia , Cinética , Leucotrieno B4/farmacologia , Inibidores de Lipoxigenase , Masoprocol/farmacologia
12.
J Interferon Res ; 9 Suppl 1: S33-6, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2681442

RESUMO

Patients receiving large amounts of interferon (IFN), particularly cloned IFN-alpha, have been reported to develop antibodies to IFN-alpha. We used a neutralization technique bioassay to monitor 175 patients undergoing recombinant (r) IFN-alpha 2b therapy in an attempt to correlate antibody production to disease progression. Only 1 patient being treated for chronic myelogenic leukemia produced antibodies. Our findings indicate that rIFN-alpha 2b has minimal antigenicity, even when administered for prolonged periods of time.


Assuntos
Anticorpos/análise , Interferon Tipo I/imunologia , Interferon-alfa/imunologia , Adolescente , Adulto , Idoso , Anticorpos/imunologia , Reações Antígeno-Anticorpo , Feminino , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Itália , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Proteínas Recombinantes
13.
Antiviral Res ; 11(5-6): 299-305, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2802571

RESUMO

Under single growth cycle conditions in C8166 lymphoblastoid cells human immunodeficiency virus shows a replication curve which is completed at 24 h post-infection. At lower multiplicity of infection virus yield peaks at approximately 72 h post-infection but in both cases the titer of the virus released in the medium is negligible with respect to that which remains cell-associated. A method based on back-titration of virus in cryolysates of C8166 cells infected with HIV and treated with antiviral compounds has been used to evaluate HIV sensitivity to such agents. Under single growth cycle conditions dose response curves appear linear and permit rapid and accurate determination of the endpoint activity. Under multiple growth cycle conditions the inhibitory activity may be measured during the exponential growth phase, at 48 h post-infection. This method, which directly measures production of infectious virus rather than indirect probes of viral replication such as reverse transcriptase or antigen production, offers the advantage of a precise determination of the degree of activity of antivirals also acting on viral assembly or release.


Assuntos
Antivirais/farmacologia , HIV/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular , Relação Dose-Resposta a Droga , Estudos de Avaliação como Assunto , HIV/fisiologia , Humanos , Testes de Sensibilidade Microbiana/métodos , Modelos Biológicos , Replicação Viral/efeitos dos fármacos
14.
Ann Ig ; 1(3-4): 647-60, 1989.
Artigo em Italiano | MEDLINE | ID: mdl-2483637

RESUMO

Acquired immunodeficiency syndrome (AIDS) is caused by infection with T-cell tropic retrovirus HIV. The disease is characterized by a profound defect in cell-mediated immunity and a number of serologic abnormalities. Among the serologic abnormalities, the presence of an unusual acid-labile interferon (IFN) has been repeatedly found, and it is considered to be a marker of infection HIV evolving toward illness. Because little is known about the relationships existing between the etiologic agent of AIDS (i.e. HIV) and acid-labile IFN alpha, we approached this problem by testing whether acid-labile IFN alpha is induced in vitro by this virus. In this paper we compared the IFN-inducing activity of free, infectious HIV to that of HIV-infected cells. A number of other enveloped viruses and virus-infected cells were used as controls. Interferon inducing activity by virions as compared to virus-infected cells was determined by incubating human PBMC either with VSV, HSV, and HIV or with cells infected with the same viruses. In this case cells were fixed with glutaraldehyde to prevent virus shedding. While VSV and HSV induced production of acid-stable IFN both as free virions and as virus-infected cells, HIV induced acid-stable IFN when applied as a viral suspension, but it did produce acid-labile IFN when virus-infected cells were used as the inducer. In fact the IFN produced under these circumstances lost more than 80% of its activity when treated to pH2, no matter whether H9/HIV or HIV infected PBMC were used as the inducer. Because acid-lability is a peculiar property of IFN gamma, whereas both native and cloned IFN alpha are completely stable under acid conditions, we compared the IFNs induced by either HIV and HIV-infected cells to standard IFN alpha and gamma preparations with respect to (i) acid stability (ii) neutralization with specific antisera (iii) apparent molecular weight estimated by gel filtration. Results indicate that HIV-induced IFN behaves exactly as standard IFN alpha, as it was completely stable at pH2, totally inactivated by anti-IFN alpha and not by anti-IFN gamma serum, and had apparent molecular weight of 20,000; conversely IFN induced by HIV-infected cells, both H9/HIV and PBMC/HIV, although sharing with IFN alpha both molecular weight and antigenic properties, was inactivated by acid treatment by more than 80%.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Síndrome da Imunodeficiência Adquirida/metabolismo , Interferon Tipo I/metabolismo , Leucócitos Mononucleares/metabolismo , Linhagem Celular , Concentração de Íons de Hidrogênio , Leucócitos Mononucleares/fisiologia
15.
Cell Immunol ; 115(1): 156-64, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3135942

RESUMO

The ability of several monoclonal antibodies (MoAbs) against beta-2-microglobulin (beta 2m) to inhibit interferon-gamma (IFN) production was assayed in peripheral blood mononuclear cells (PBMC). All of them strongly reduce IFN-gamma induction by galactose oxidase (GO), a well-characterized enzyme capable of activating T lymphocytes through mediation of macrophages. In contrast, many MoAbs directed against HLA class I (heavy chain) and class II antigens do not inhibit IFN induction by GO. On the other hand, anti-beta 2m MoAbs do not effectively reduce IFN-gamma induction by A23187, a calcium ionophore that acts on T cells in the absence of accessory cells. Competition experiments demonstrate that (i) the inhibition of anti-beta 2m antibodies was specific for beta 2m protein, and (ii) beta 2m is not itself the site of action of GO. Moreover, it is demonstrated that the addition of beta 2m to oxidated PBMC strongly enhances subsequent IFN-gamma production. Oxidation of galactose residues on glycoproteins of macrophage membrane is an obligate step for IFN-gamma induction whatever the inducer, thus our results suggest that beta 2m is involved in the mechanism of induction of IFN-gamma.


Assuntos
Indutores de Interferon/fisiologia , Interferon gama/biossíntese , Microglobulina beta-2/fisiologia , Anticorpos Monoclonais/fisiologia , Especificidade de Anticorpos , Calcimicina/farmacologia , Relação Dose-Resposta Imunológica , Galactose Oxidase/farmacologia , Humanos , Imunossupressores/fisiologia , Indutores de Interferon/imunologia , Interferon gama/antagonistas & inibidores , Leucócitos Mononucleares/metabolismo , Microglobulina beta-2/imunologia
16.
Cell Immunol ; 113(2): 376-86, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3129197

RESUMO

A novel monokine different from interleukin 1 (IL-1) is secreted from human or murine macrophages stimulated with galactose oxidase, a well-characterized enzyme able to induce marked polyclonal activation of lymphocytes. This monokine, preliminarly termed macrophage-derived blastogenic factor (MBF), stimulates resting T lymphocytes to produce interferon (IFN)-gamma and to proliferate. The apparent MW of MBF ranges between 29,000 and 35,000, although some active fractions show smaller MW ranging from 2000 to 7000, as demonstrated by gel filtration. The biological relationship between MBF and IL-1 was examined and it was found that MBF (1) is able to induce IFN-gamma production and proliferation by T lymphocytes in the absence of other inducers, (2) is not able to activate PHA-stimulated C3H mouse thymocytes, (3) is not able to induce production of IFN-beta by fibroblast cultures, (4) is resistant to proteolytic enzymes, and (5) is not neutralized by antibodies to IL-1. MBF was released in the macrophage supernatants in two waves after the oxidation process, namely, after 15 min and 2.5 hr, and each wave was capable of inducing lymphocyte activation at dilutions up to 1:32. Because the oxidation of galactose residues on cell surface structures is considered a general feature of lymphocyte activation whatever the inducer, it seems that MBF may be a mediator involved in mitogenic activation of T cells leading to IFN-gamma production and proliferation.


Assuntos
Produtos Biológicos/fisiologia , Interferon gama/biossíntese , Ativação Linfocitária , Macrófagos/fisiologia , Animais , Humanos , Técnicas Imunológicas , Técnicas In Vitro , Interferon Tipo I/biossíntese , Interleucina-1/fisiologia , Camundongos , Peso Molecular , Monocinas , Peptídeo Hidrolases/farmacologia , Timo/citologia , Fatores de Tempo
17.
J Interferon Res ; 8(2): 193-200, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3132511

RESUMO

A23187 in combination with phorbol myristate acetate (PMA) strongly induces production of interferon-gamma (IFN-gamma) by human peripheral blood mononuclear cells (PBMC) and even by murine PBMC, which respond poorly to A23187 alone. Macrophage depletion of PBMC strongly reduces IFN-gamma production induced by several mitogens, but does not affect IFN-gamma production induced by A23187 and PMA. In addition the same stimuli are able in combination to induce strong amounts of IFN-gamma, even in the Jurkat T cell line. The protein kinase C inhibitor 1-(5-isoquinolinylsulfonyl)-2-methyl-piperazine (H-7) and the calmodulin antagonist N-(6-aminoehexyl)-5-chloro-1-naphthalenesulfonamide (W-7) were examined for their ability to inhibit IFN-gamma production induced by PMA and A23187. At concentrations near the Ki for protein kinase C, H-7 failed to inhibit PMA- and A23187-induced IFN-gamma production. In contrast, W-7 at low concentrations inhibited IFN-gamma production induced by the same stimuli. In addition OAG, which is known to directly activate protein kinase C, failed to act synergistically with A23187 in the induction of IFN-gamma. On the basis of these results we propose that A23187 and PMA may mimic the early steps of lymphocyte activation, without the requirement of macrophage, bypassing antigen-, or lectin-induced signal. Our results suggest that Ca2+-calmodulin-dependent reactions other than protein kinase C activation may be essential for IFN-gamma production, at least at level of the producing cells.


Assuntos
Cálcio/fisiologia , Calmodulina/fisiologia , Interferon gama/biossíntese , Leucócitos Mononucleares/metabolismo , Proteína Quinase C/fisiologia , Animais , Calcimicina/farmacologia , Células Cultivadas , Humanos , Camundongos , Proteína Quinase C/antagonistas & inibidores , Acetato de Tetradecanoilforbol/farmacologia
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