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1.
Virology ; 255(2): 285-93, 1999 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10069954

RESUMO

Primary infection of macaques with pathogenic isolates of simian immunodeficiency virus (SIV) (as a model of HIV infection in humans) represents a unique opportunity to study early lentivirus/host interactions. We sought to determine whether there is a temporal relationship linking SIV replication and dissemination and the expression of the chemokine RANTES (regulated upon activation normal T cell expressed and secreted) and the SIV/HIV coreceptor CCR5 in different tissues during acute SIV infection of macaques. Four cynomolgus macaques were inoculated intravenously with a pathogenic primary isolate of SIVmac251. RT-PCR was used to monitor the expression of RANTES and CCR5 mRNA in fresh isolated mononuclear cells from blood, lymph node, and bronchoalveolar lavages. These expressions were compared to those of IFN-gamma as an indicator of the development of the immune response and to another receptor for RANTES, CCR1, which is not described as a coreceptor for SIV/HIV-1 entry. An enhancement of CCR1/CCR5 mRNA expression was noticed during primary SIVmac251 infection of macaques, mainly in tissue. In the three different compartments investigated, IFN-gamma and RANTES overexpression was noticed by the time of systemic viral replication containment. Our results put CCR5 and RANTES mRNA expression back in the context of inflammatory and immune responses to SIV primary infection.


Assuntos
Quimiocina CCL5/genética , Regulação da Expressão Gênica , Interferon gama/genética , Receptores CCR5/genética , Receptores de Quimiocinas/genética , Síndrome de Imunodeficiência Adquirida dos Símios , Animais , Lavagem Broncoalveolar , Feminino , Seguimentos , Cinética , Leucócitos Mononucleares , Linfonodos , Macaca fascicularis , RNA Mensageiro , Receptores CCR1 , Síndrome de Imunodeficiência Adquirida dos Símios/fisiopatologia , Vírus da Imunodeficiência Símia , Subpopulações de Linfócitos T
2.
Hum Gene Ther ; 10(3): 429-40, 1999 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-10048395

RESUMO

We are developing a method of gene therapy of HIV infection based on the low constitutive expression of an interferon beta (IFN-beta) gene in HIV target cells. Herein we report the first step in the development of a relevant animal model, provided by the macaque (Macaca fascicularis) infected with a pathogenic SIVmac251 isolate. To avoid the possibility of in vivo rejection of macaque lymphocytes expressing Hu IFN-beta, we have PCR-amplified and sequenced the Ma IFN-beta-coding sequence, and placed it under the control of a PstI-NruI 0.6-kb fragment of the murine H-2Kb gene promoter in the MFG-K(b)MaIFNbeta retroviral vector. Lymphocytic CEMX174 cells, transduced by coculture on packaging cells with this construct, harbored a mean of 0.07 to 1.2 copies of the IFN-beta transgene per cell, and were characterized by an IFN production ranging from 75 to 750 units per 5 x 10(5) cells per 3 days. The IFN-beta-transduced populations displayed an enhanced resistance against the pathogenic SIVmac251 isolate. Control experiments showed that the enhanced resistance could not be ascribed to the Ma IFN-beta released during the 3 days of coculture by the packaging cells, or to the mere transduction with a retroviral vector. Macaque lymphocytes transduced by the MFG-K(b)MaIFNbeta retroviral vector by coculture on packaging cells, acquired a mean number of IFN-beta transgene copies per cell ranging from 0.03 to 0.1. Such transduction led to the release of IFN-beta into the culture medium, ranging from 10 to 20 units per 5 x 10(5) cells per 3 days. This increased the anti-SIV resistance of the lymphocytes, as demonstrated by a decreased p27 antigen release into the culture medium, without affecting lymphocyte proliferation.


Assuntos
Imunidade Celular , Interferon beta/genética , Linfócitos/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Células 3T3 , Animais , Sequência de Bases , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Produtos do Gene rex/análise , Terapia Genética , Vetores Genéticos , Humanos , Interferon beta/biossíntese , Macaca fascicularis , Camundongos , Dados de Sequência Molecular , Fenótipo , Retroviridae , Homologia de Sequência de Aminoácidos , Vírus da Imunodeficiência Símia/imunologia , Fatores de Tempo , Transdução Genética
3.
Virology ; 243(1): 12-20, 1998 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-9527911

RESUMO

Sexual transmission is the major cause of the AIDS epidemic. For the development of new antiviral and vaccine strategies, we therefore need to understand the mechanisms by which lentiviruses cross the mucosal barrier and the subsequent pathogenic consequences. For this purpose, experimental approaches are greatly facilitated by the development of relevant animal models. In this study, macaques were inoculated intravenously, intrarectally, or intravaginally with a pathogenic cell-free isolate of SIVmac251. Patterns of virological and immunological events significantly differed between vaginally (transient viremia, late seroconversion) and intravenously or intrarectally inoculated monkeys (persistent viremia and early seroconversion). Two weeks after infection, analysis of the env gene nucleotide sequences of proviruses recovered from PBMCs demonstrated that most of the differences were observed in the V1 loop. Three viral variants were specifically associated with vaginal transmission, whereas no such selection was evidenced after intravenous or intrarectal transmissions. These results are in favor of specific mechanisms associated with vaginal transmission, implicating viral envelope structure.


Assuntos
Proteína gp120 do Envelope de HIV/fisiologia , Mucosa Intestinal/virologia , Glicoproteínas de Membrana , Síndrome de Imunodeficiência Adquirida dos Símios/transmissão , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/fisiologia , Vagina/virologia , Proteínas do Envelope Viral , Sequência de Aminoácidos , Animais , Feminino , Macaca , Dados de Sequência Molecular , Filogenia , Viremia , Replicação Viral
4.
Res Virol ; 149(1): 53-68, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9561564

RESUMO

We developed an animal model for the male-to-female transmission of human immunodeficiency virus, consisting of an atraumatic vaginal application of simian immunodeficiency virus onto the intact vaginal mucosa of cynomolgus macaques. Different doses of a pathogenic isolate of SIVmac251, with or without seminal plasma, were infused into the vaginas of female macaques. Infection of macaques could be achieved after a single exposure to the virus. Two patterns of infection were underscored with no relation to the virus dose inoculated: in 50% of the monkeys, SIV was persistently recovered and a strong antibody response to SIV was evidenced in blood and vaginal secretions. In the other infected animals, SIV infection was only transiently evidenced and a weak systemic antibody response was detected. It appeared that the presence of seminal plasma may be implicated in this variability only when low doses of virus are inoculated. Sequence analysis of the env gene of SIV revealed that most of the persistently viraemic animals were infected with a viral variant different from that of transiently viraemic macaques.


Assuntos
Infecções por HIV/transmissão , Síndrome de Imunodeficiência Adquirida dos Símios/transmissão , Vírus da Imunodeficiência Símia/imunologia , Vírus da Imunodeficiência Símia/isolamento & purificação , Vagina/virologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/análise , Anticorpos Antivirais/sangue , Contagem de Linfócito CD4 , Modelos Animais de Doenças , Feminino , Humanos , Leucócitos Mononucleares/virologia , Macaca fascicularis , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Alinhamento de Sequência , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/genética , Descarga Vaginal/virologia , Viremia
5.
Res Virol ; 149(6): 341-54, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9923010

RESUMO

This study evaluates the consequences of antiretroviral treatment of the acute simian immunodeficiency virus (SIV) primary infection on virus load and cytokine responses. Four cynomolgus macaques were inoculated intravenously with a pathogenic primary isolate (SIVmac251). Animals were pretreated with 10.8 mg/kg/day of dideoxyinosine (ddI) from 4 days before inoculation, and treatment was continued for 28 days. Proinflammatory (IL6, IL1 beta and TNF alpha) and antiinflammatory (IL10) cytokine and lymphokine (IL2, IL4 and IFN gamma) polymerase chain reaction (PCR) ratios were monitored in unmanipulated peripheral blood mononuclear cells (PBMCs) during acute infection by using a semiquantitative reverse transcription (RT)-PCR method. PBMC-associated virus loads were dramatically reduced compared to those of placebo-treated macaques. Nevertheless, a transient rise in IL6, IL1 beta, TNF alpha and IL10 mRNA expression was observed in PBMCs. IL2, IL4 and IFN gamma mRNAs were either undetectable or weakly detectable throughout the study, with no major changes. Despite a dramatic reduction in the acute viral loads in ddI-treated monkeys, early cytokine mRNA profiles were comparable to those of untreated SIVmac251-infected monkeys. Contrary to what was previously evidenced during primary infection with an attenuated SIV clone, no increase in IL2 and IL4 mRNA was detected in PBMCs of the ddI-treated monkeys, although these monkeys exhibited virus loads similar to those evidenced in macaques infected by attenuated SIV. These data indicate that differential lymphokine expression patterns found in pathogenic and Nef-truncated SIV-infected monkeys may not be strictly dependent on virus load levels.


Assuntos
Antivirais/uso terapêutico , Citocinas/imunologia , Didanosina/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Carga Viral , Doença Aguda , Animais , Anticorpos Antivirais/imunologia , Citocinas/genética , Seguimentos , Hematologia , Leucócitos Mononucleares , Macaca fascicularis , Reação em Cadeia da Polimerase , Síndrome de Imunodeficiência Adquirida dos Símios/virologia
6.
J Med Primatol ; 26(1-2): 19-26, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9271185

RESUMO

We have used semiquantitative RT-PCR to monitor the expression of mRNA encoding chemoattractant factors IP-10, MIP-1alpha, and IL-16 in freshly isolated peripheral blood mononuclear cells (PBMCs), lymph node mononuclear cells (LNMCs), and mononuclear cells obtained after bronchoalveolar lavages (BALMCs) of two cynomolgus macaques inoculated intravenously with a pathogenic isolate of simian immunodeficiency virus, SIVmac251. Concomitant with the peak of systemic viral replication (two weeks after experimental inoculation) and proinflammatory cytokine IL-6 mRNA expression, high levels of MIP-1alpha and IP-10 mRNA were produced in LNMCs and BALMCs. In BALMCs, in which we have reported a marked progressive overexpression of IFN-gamma mRNA coinciding with an increase in the CD8+ lymphocyte percentages, we noticed a progressive overexpression of IL-16 mRNA. Our results suggest the role of chemokines IP-10, MIP-1alpha, and IL-16 in the development of inflammatory and immune responses during the early stages of lentiviral infection.


Assuntos
Quimiocinas CXC , Quimiocinas/biossíntese , Interleucina-16/biossíntese , Proteínas Inflamatórias de Macrófagos/biossíntese , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Animais , Quimiocina CCL3 , Quimiocina CCL4 , Quimiocina CXCL10 , Imunidade Celular , Inflamação/imunologia , Leucócitos Mononucleares/virologia , Linfonodos/citologia , Macaca fascicularis , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese , Vírus da Imunodeficiência Símia/genética
7.
AIDS Res Hum Retroviruses ; 12(13): 1263-72, 1996 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-8870848

RESUMO

We used semiquantitative RT-PCR to monitor the expression of mRNA encoding cytokines (IL-1 beta, IL-6, TNF-alpha, and IL-10) and IFN-gamma in fresh isolated peripheral blood mononuclear cells (PBMCs), lymph node mononuclear cells (LNMCs), and mononuclear cells obtained after bronchoalveolar lavages (BALMCs), of four cynomolgus macaques inoculated intravenously with a pathogenic isolate of simian immunodeficiency virus (SIVmac251). To investigate the effects of the viral load on the expression of the cytokines, two monkeys received 30 mg kg-1 day-1 of didanosine (ddI). The two nontreated monkeys became infected and seroconverted, whereas the ddI-treated monkeys were completely protected as demonstrated by all criteria of diagnosis of SIV infection. Concomitant with the peak of viral replication (2 weeks after the experimental inoculation), high levels of IL-6 mRNA were produced in PBMCs, LNMCs, and BALMCs of the two placebotreated infected monkeys. Overexpression of TNF-alpha and IL-10 mRNAs was sometimes observed in LNMCs and BALMCs. A progressive overexpression of IFN-gamma mRNA, starting 2 weeks after experimental inoculation, was observed in BALMCs from infected animals. Concurrently, a marked increase in the CD8+ lymphocyte percentage in the BAL fluids was detected by FACS analysis. Thus, our results emphasize the importance of a comparative study of the expression of cytokines in different tissues. They suggest the interactions of monocyte/macrophage monokine production with viral replication, as well as the role of IFN-gamma in the development of lung cellular immunity to SIV infection.


Assuntos
Citocinas/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Doença Aguda , Animais , Anticorpos Antivirais/sangue , Antivirais/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular , Citocinas/genética , Didanosina/uso terapêutico , Feminino , Seguimentos , Expressão Gênica , Proteína do Núcleo p24 do HIV/imunologia , Interferon gama/genética , Interferon gama/imunologia , Interleucina-1/genética , Interleucina-1/imunologia , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Leucócitos Mononucleares/imunologia , Macaca fascicularis , Masculino , RNA Mensageiro , Síndrome de Imunodeficiência Adquirida dos Símios/sangue , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
8.
Virology ; 221(2): 260-70, 1996 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-8661436

RESUMO

To test the protection afforded by a weakly pathogenic HIV-2 isolate against the superinfection or development of SIV-induced disease, we intrarectally challenged six HIV-2-preinfected rhesus monkeys with a pathogenic isolate of SIVmac251. At the time of SIV challenge, none of these HIV-2-infected animals was positive for virus isolation, p27-Gag antigenemia, or HIV-2 provirus detection in PBMCs or peripheral lymph nodes. However, all monkeys exhibited anti-HIV-2 antibody titers ranging from 10(2) to 10(3). Neutralizing antibodies against the challenge SIV strain were also detected in two animals. After rectal exposure to SIVmac251, five of the six HIV-2-preinfected macaques were superinfected. SIVmac251 DNA sequences were detected repeatedly in the PBMCs of the five superinfected animals and the two controls, whereas no HIV-2 provirus was detected for 14 months postchallenge. The one monkey that resisted superinfection was negative for all SIV infection criteria. This monkey exhibited the highest anti-SIV ELISA and cross-neutralizing antibody titers on the day of SIV challenge. Preinfection with a weakly pathogenic HIV-2 ROD isolate protected one of six macaques from infection with the closely related pathogenic SIVmac251 isolate, but no protection from the progression of disease was evidenced in the other five.


Assuntos
Infecções por HIV/imunologia , HIV-2/imunologia , Vírus da Imunodeficiência Símia/imunologia , Superinfecção/virologia , Vacinas contra a AIDS/imunologia , Animais , Sequência de Bases , Linhagem Celular , Células Cultivadas , DNA Viral/análise , Feminino , Anticorpos Anti-HIV/sangue , Anticorpos Anti-HIV/imunologia , Infecções por HIV/prevenção & controle , Humanos , Leucócitos Mononucleares/virologia , Macaca , Masculino , Dados de Sequência Molecular , Reto , Superinfecção/imunologia , Subpopulações de Linfócitos T/imunologia
9.
Proc Natl Acad Sci U S A ; 93(8): 3658-63, 1996 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-8622992

RESUMO

Comparison of immune responses to infection by a pathogenic or a nonpathogenic immunodeficiency virus in macaques may provide insights into pathogenetic events leading to simian AIDS. This work is aimed at exploring cytokine expression during infection by simian immunodeficiency virus (SIV). We used semiquantitative reverse transcription-PCR to monitor interleukin (IL)-2/interferon (IFN)-gamma (Th1-like), and IL-4/IL-10 (Th2-like) expression in unmanipulated peripheral blood mononuclear cells (PBMCs), during the acute phase of infection of eight cynomolgus macaques (Macaca fascicularis) with a pathogenic primary isolate of SIVmac251 (full-length nef), and of four other cynomolgus macaques by an attenuated molecular clone of SIVmac251 (nef-truncated). All the monkeys became infected, as clearly shown by the presence of infected PBMCs and by seroconversion. Nevertheless, PBMC-associated virus loads and p27 antigenemia in monkeys infected by the attenuated virus clone remained lower than those observed in animals infected with the pathogenic SIVmac251 isolate. A rise of IL-10 mRNA expression occurred in both groups of monkeys coincident with the peak of viral replication. In monkeys infected with the pathogenic SIVmac251, IL-2, IL-4, and IFN-gamma mRNAs were either weakly detectable or undetectable. On the contrary, animals infected by the attenuated virus exhibited an overexpression of these cytokine mRNAs during the first weeks after inoculation. The lack of expression of these cytokines in monkeys infected with the pathogenic primary isolate may reflect early immunodeficiency.


Assuntos
Citocinas/genética , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia , Doença Aguda , Animais , Anticorpos Antivirais/sangue , Relação CD4-CD8 , Expressão Gênica , Genes nef , Interferon gama/genética , Interleucina-10/genética , Interleucina-2/genética , Interleucina-4/genética , Leucócitos Mononucleares/imunologia , Macaca fascicularis , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/genética , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/genética , Vírus da Imunodeficiência Símia/imunologia , Vírus da Imunodeficiência Símia/patogenicidade , Subpopulações de Linfócitos T/imunologia
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