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1.
J Virol ; 89(11): 5772-87, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25833047

RESUMO

UNLABELLED: A number of men receiving prolonged suppressive highly active antiretroviral therapy (HAART) still shed human immunodeficiency virus (HIV) in semen. To investigate whether this seminal shedding may be due to poor drug penetration and/or viral production by long-lived cells within male genital tissues, we analyzed semen and reproductive tissues from macaques chronically infected with simian immunodeficiency virus mac251 (SIVmac251) who were treated for 4 months with HAART, which was intensified over the last 7 weeks with an integrase inhibitor. We showed that a subset of treated animals continued shedding SIV in semen despite efficient HAART. This shedding was not associated with low antiretroviral drug concentrations in semen or in testis, epididymis, seminal vesicles, and prostate. HAART had no significant impact on SIV RNA in the urethra, whereas it drastically reduced SIV RNA levels in the prostate and vas deferens and to a lesser extent in the epididymis and seminal vesicle. The only detectable SIV RNA-positive cells within the male genital tract after HAART were urethral macrophages. SIV DNA levels in genital tissues were not decreased by HAART, suggesting the presence throughout the male genital tract of nonproductively infected cells. In conclusion, our results demonstrate that 4 months of HAART induced variable and limited control of viral infection in the male reproductive organs, particularly in the urethra, and suggest that infected long-lived cells in the male genital tract may be involved in persistent seminal shedding during HAART. These results pave the way for further investigations of male genital organ infection in long-term-treated infected individuals. IMPORTANCE: A substantial subset of men receiving prolonged HAART suppressing viral loads in the blood still harbor HIV in semen, and cases of sexual transmission have been reported. To understand the origin of this persistence, we analyzed the semen and male reproductive tissues from SIV-infected macaques treated with HAART. We demonstrated that persistent seminal shedding was not linked to poor drug penetration in semen or semen-producing prostate, seminal vesicle, epididymis, and testis. We revealed that HAART decreased SIV RNA to various extents in all male genital organs, with the exception of the urethra, in which SIV RNA(+) macrophages were observed despite HAART. Importantly, HAART did not impact SIV DNA levels in the male genital organs. These results suggest that infection of male genital organs, and particularly the urethra, could be involved in the release of virus in semen during HAART.


Assuntos
Terapia Antirretroviral de Alta Atividade , Genitália Masculina/virologia , Sêmen/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/isolamento & purificação , Uretra/virologia , Animais , Antirretrovirais/administração & dosagem , Antirretrovirais/farmacocinética , Macaca , Masculino , Eliminação de Partículas Virais
2.
Hum Reprod ; 23(9): 2095-103, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18567898

RESUMO

BACKGROUND: The immuno-privileged status of the testis is essential to the maintenance of its functions, and innate immunity is likely to play a key role in limiting harmful viral infections, as demonstrated in the rat. In men mumps virus infects Leydig cells and has deleterious effects on testosterone production and spermatogenesis. The aim of this study was to test whether mumps virus infection of isolated human Leydig cells was associated with an inhibition of their innate antiviral defences. METHODS: Leydig cell production of mRNA and protein for interferons (IFNs) and of three antiviral proteins-2'5' oligoadenylate synthetase (2'5'OAS), double-stranded RNA-activated protein kinase (PKR) and MxA-was investigated, in the absence or presence of mumps virus or viral stimuli including poly I:C, a mimetic of RNA viruses replication product. RESULTS: Stimulated or not, human Leydig cells appeared unable to produce routinely detectable IFNs alpha, beta and gamma. Although the level of PKR remained unchanged after stimulation, the expression of 2'5'OAS and MxA was enhanced following either mumps virus or poly I:C exposure (P < 0.05 versus control). CONCLUSIONS: Overall, our results demonstrate that mumps virus replication in human Leydig cells is not associated with a specific inhibition of IFNs or 2'5'OAS, MxA and PKR production and that these cells display relatively weak endogenous antiviral abilities, as opposed to their rat counterparts.


Assuntos
Antivirais/farmacologia , Imunidade Inata/fisiologia , Indutores de Interferon/farmacologia , Células Intersticiais do Testículo/virologia , Vírus da Caxumba/imunologia , Poli I-C/farmacologia , 2',5'-Oligoadenilato Sintetase/metabolismo , Células Cultivadas , Proteínas de Ligação ao GTP/metabolismo , Humanos , Interferons/metabolismo , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/imunologia , Masculino , Vírus da Caxumba/patogenicidade , Proteínas de Resistência a Myxovirus , Replicação Viral/imunologia , eIF-2 Quinase/metabolismo
3.
Hum Reprod ; 21(6): 1564-75, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16497692

RESUMO

BACKGROUND: Over recent decades, recurring efforts have been devoted to developing testicular cell or tissue cultures for basic and clinical research. However, there remains much confusion, particularly concerning the fate of human germ cells in culture. OBJECTIVE: To reassess the status of human testicular cell types as well as the ability of germ cells to divide and differentiate in organotypic culture. METHODS: Human testicular fragments were maintained for 2 weeks in culture. The viability and functionality of testicular cells were assessed using light and electronic microscopy, apoptotic cell labelling, 5-bromo-2'-deoxyuridine (BrdU) incorporation, immunohistochemistry and quantitative PCR against specific cell markers. RESULTS: A gradual loss of meiotic and post-meiotic germ cells occurred throughout the culture period, irrespective of the presence of gonadotrophins. However, all germ cell types remained traceable for up to 16 days, some still dividing and differentiating at a rate compatible with the in vivo situation. Good maintenance of the general architecture of the explants associated with clearly quantifiable levels of several somatic cell markers was observed. CONCLUSION: Although this culture model is clearly unsuitable for preparing germ cells for therapeutic purposes, it does represent a most valuable tool for testing the effects of biological and chemical agents on testicular tissue.


Assuntos
Técnicas de Cultura de Órgãos/métodos , Testículo/patologia , Testículo/ultraestrutura , Bromodesoxiuridina/farmacologia , Diferenciação Celular , AMP Cíclico/metabolismo , Fragmentação do DNA , Células Germinativas/metabolismo , Gonadotropinas/metabolismo , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Meiose , Testículo/metabolismo , Fatores de Tempo
4.
Cancer ; 92(11): 2778-85, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11753951

RESUMO

BACKGROUND: Testicular germ cell tumors are the most common malignancy in young males, and the frequency of these tumors has risen dramatically over the last century. Because it is known that the MAGE genes are expressed in a wide variety of tumors but are expressed only in the mitotic spermatogonia (germ cells) and in the primary spermatocytes in the normal testis, the authors screened the expression of MAGE-A4 in a panel of testicular germ cell tumors. METHODS: Monoclonal antibody 57B raised against MAGE-A4 was tested immunohistochemically on 12 classical seminomas, 5 anaplastic seminomas, 10 various specimens of nonseminomatous germ cell tumors (NSGCTs), 2 combined tumors containing seminoma components, 1 Sertoli cell tumor, 2 Leydig cell tumors, and 15 carcinomas in situ (CIS). In addition, monoclonal antibody 57B was tested on embryonic gonad (age 8 weeks) and fetal gonads (ages 15 weeks, 17 weeks, and 28 weeks). RESULTS: Classical seminomas uniformly and specifically expressed MAGE-A4 compared with anaplastic seminomas and NSGCTs, which were negative for this antigen. Specific expression of MAGE-A4 also was seen in subpopulations of CIS cells, providing additional evidence for heterogeneity of the phenotype of these cells, in which it is believed that differentiation and proliferation generate seminomas and NSGCTs. Finally, MAGE-A4 was expressed in the fetal precursors of the stem germ cells from 17 weeks of gestation onward, in accordance the fact that CIS can arise from prespermatogonia in the fetus. CONCLUSIONS: MAGE-A4 can be considered a potential specific marker for normal premeiotic germ cells and germ cell tumors and can be used to characterize classical seminomas.


Assuntos
Antígenos de Neoplasias/análise , Biomarcadores Tumorais/análise , Gônadas/metabolismo , Proteínas de Neoplasias , Neoplasias Testiculares/metabolismo , Testículo/metabolismo , Antígenos de Neoplasias/imunologia , Biomarcadores Tumorais/imunologia , Gônadas/embriologia , Humanos , Imuno-Histoquímica , Masculino , Prognóstico , Neoplasias Testiculares/diagnóstico
5.
Eur Cytokine Netw ; 11(4): 690-8, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11125315

RESUMO

Testicular inflammation is classically observed in the pathogenesis of viral and bacterial infection or tumoral invasion. In these situations, leukocyte infiltration is generally encountered. GRO/KC (growth-related oncogene) and IP-10/mob-1 (IFN-gamma-inducible protein) are two CXC-chemokines which attract neutrophils and activated T lymphocytes, respectively, have been studied for their ability to participate to testicular inflammation (orchitis). In the present work, using Northern blot and immunocytochemistry, we aimed to investigate whether GRO/KC and IP-10/mob-1 are produced within the seminiferous tubules of the testis and if these chemokines are induced by a number of pro-inflammatory cytokines and lipopolysaccharides (LPS). Our results show that GRO/KC and IP-10/mob-1 mRNAs were never found in germ cells, whether they were stimulated or not. In contrast, GRO/KC mRNA was expressed by isolated peritubular cells when stimulated by interleukin-1 alpha and beta (IL-1 alpha and IL-1 beta) or LPS and to a lesser extent by tumor necrosis factor-alpha (TNF-alpha) and by Sertoli cells when the latter were stimulated by rIL-alpha and rIL-1 beta and to a lesser extent by TNF-alpha and LPS. Moreover, IP10/mob-1 transcripts were strongly induced in peritubular cells by interferon-alpha (IFN-alpha) and IFN-gamma, whereas, in isolated Sertoli cells, INF-alpha and TNF-alpha were the only potent inducers. The kinetics of GRO/KC and IP-10/mob-1 mRNA expression by peritubular and Sertoli cells (significant stimulation as early as 1 hour and 4 hours post-exposure to the stimuli, respectively) are compatible with the hypothesis of a rapid mobilisation of these cells in an inflammatory process. Moreover, the dose-dependent effects of pro-inflammatory cytokines to induce a chemokine response were compatible with a high sensitivity of peritubular and Sertoli cells in orchitis. In conclusion, this present study shows that 2 CXC-chemokines, GRO/KC and IP10/mob-1, are produced by testicular somatic cells of seminiferous tubules, strongly indicating a likely role of these chemokines in the accumulation of neutrophils and T lymphocytes during orchitis of various origins.


Assuntos
Quimiocinas CXC/genética , Citocinas/genética , Túbulos Seminíferos/imunologia , Animais , Northern Blotting , Células Cultivadas , Quimiocina CXCL10 , Quimiocinas , Quimiocinas CXC/biossíntese , Citocinas/biossíntese , Citocinas/farmacologia , Relação Dose-Resposta Imunológica , Células Germinativas/imunologia , Imuno-Histoquímica , Cinética , Masculino , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Túbulos Seminíferos/citologia , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/imunologia , Espermatogônias/imunologia , Ativação Transcricional
6.
Biol Reprod ; 62(5): 1427-35, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10775197

RESUMO

Testicular inflammation is classically observed in pathogenesis caused by infectious agents, environmental toxins, trauma, or autoimmune reactions and can lead to transitory or even permanent sterility. In these situations, a leukocyte infiltration is generally encountered. Macrophage inflammatory proteins (MIP)-1alpha and -1beta and monocyte chemoattractant protein-1 (MCP-1) are CC-chemokines involved in macrophage and lymphocyte chemoattraction. In the present study, using reverse transcription-polymerase chain reaction, Northern blot, and a specific ELISA, we investigated whether or not these chemokines are present within the testis and whether they are induced by a number of proinflammatory cytokines and lipopolysaccharides (LPS). MIP-1alpha and MIP-1beta were not detected in Sertoli cells, germ cells, peritubular cells, or Leydig cells. In contrast, MCP-1 mRNA and protein were found to be expressed by control isolated peritubular cells, and expression was markedly stimulated by interleukin-1alpha and-1beta (IL-1alpha and IL-1beta), tumor necrosis factor alpha (TNF-alpha), interferon gamma, and LPS. Leydig cells expressed MCP-1 when stimulated by IL-1beta. In contrast, MCP-1 was not found to be produced by Sertoli cells or germ cells as established by Northern blot and ELISA techniques. The kinetics of MCP-1 production by peritubular cells, as demonstrated by expression as early as 8 h poststimulation, are compatible with there being a rapid mobilization of these cells and this chemokine in an inflammatory process. Moreover, MCP-1 production by peritubular cells after half-maximal stimulation by LPS, TNF-alpha, and IL-1beta (2 pg/ml-0.9 ng/ml) is also compatible with the physiologic concentrations of the proinflammatory cytokines generally found in an inflammatory site. It is concluded that MCP-1 is produced by Leydig cells and peritubular cells and that it could be involved in the mobilization and migration of leukocytes observed during testicular inflammation.


Assuntos
Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Proteínas Inflamatórias de Macrófagos/genética , Proteínas Inflamatórias de Macrófagos/metabolismo , Testículo/metabolismo , Animais , Northern Blotting , Células Cultivadas , Quimiocina CCL3 , Quimiocina CCL4 , Regulação da Expressão Gênica , Interleucina-1/farmacologia , Células Intersticiais do Testículo/fisiologia , Lipopolissacarídeos/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley , Células de Sertoli/fisiologia , Espermatozoides/fisiologia , Testículo/citologia , Testículo/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia
7.
J Hepatol ; 13 Suppl 3: S41-7, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1667668

RESUMO

Alterations in extracellular matrix occur in many chronic liver diseases leading to the formation of hepatic fibrosis. We have studied the effects of the putative hepatoselective fibrosuppressive compound HOE 077, a proinhibitor of prolyl 4-hydroxylase, on normal adult human and rat hepatocytes in primary culture. In human hepatocyte cultures, the cytotoxicity of HOE 077 was assessed after a 20-h treatment at concentrations ranging from 0.125 to 2 mg/ml of medium. No significant change was found in cell morphology, neutral red uptake, red oil staining, lactate dehydrogenase release, tetrazolium salt reduction, ethoxyresorufin O-deethylase activity and protein synthesis; however, HOE 077 slightly decreased DNA synthesis at 2 mg/ml. In rat hepatocyte cultures, the cytotoxicity of the compound was assessed by testing the same parameters after a daily exposure of cultures for 2 days or 4 days, at concentrations ranging from 0.25 to 4.5 mg/ml of medium. Whatever the concentration, the compound had no obvious morphological effect. However, hepatocytes were less spread at the concentration of 4.5 mg/ml. HOE 077 at 2 mg/ml slightly decreased neutral red uptake but was without obvious effect on protein synthesis after 2 days. By contrast, on day 4, protein synthesis was markedly reduced in hepatocyte cultures exposed to HOE 077 at 4.5 mg/ml. Hydroxyproline content determination in media from 4-day-old hepatocyte cultures incubated with HOE 077 at 0.5 to 4.5 mg/ml, showed a dose-dependent decrease in the hydroxyproline/proline ratio in acetic acid soluble material. By indirect immunoperoxidase, intracellular collagen IV was found to be inhibited in hepatocyte cultures after 4 days of exposure to 4.5 mg/ml HOE 077.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Fígado/efeitos dos fármacos , Pró-Colágeno-Prolina Dioxigenase/antagonistas & inibidores , Piridinas/farmacologia , Animais , Radioisótopos de Carbono , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Replicação do DNA/efeitos dos fármacos , Feminino , Humanos , Leucina/metabolismo , Fígado/citologia , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Biossíntese de Proteínas , Ratos , Ratos Endogâmicos , Timidina/metabolismo , Trítio
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