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1.
Sci Rep ; 13(1): 14908, 2023 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689795

RESUMO

HBV/HCV co-infection is common in HIV-1-infected prisoners. To investigate the characteristics of HIV co-infections, and to evaluate the molecular heterogeneity of HIV, HBV and HCV in prisoners, we carried-out a multicenter cross-sectional study, including 65 HIV-1-infected inmates enrolled in 5 Italian detention centers during the period 2017-2019. HIV-1 subtyping showed that 77.1% of inmates were infected with B subtype and 22.9% with non-B subtypes. Italian nationals were all infected with subtype B (93.1%), except two individuals, one infected with the recombinant form CRF72_BF1, and the other with the HIV-1 sub-subtype A6, both previously not identified in inmates of Italian nationality. Non-Italian nationals were infected with subtype B (52.6%), CRFs (36.8%) and sub-subtypes A1 and A3 (5.2%). HIV variants carrying resistance mutations to NRTI, NNRTI, PI and InSTI were found in 7 inmates, 4 of which were never exposed to the relevant classes of drugs associated with these mutations. HBV and/or HCV co-infections markers were found in 49/65 (75.4%) inmates, while 27/65 (41.5%) showed markers of both HBV and HCV coinfection. Further, Italian nationals showed a significant higher presence of HCV markers as compared to non-Italian nationals (p = 0.0001). Finally, HCV phylogenetic analysis performed in 18 inmates revealed the presence of HCV subtypes 1a, 3a, 4d (66.6%, 16.7% and 16.7%, respectively). Our data suggest the need to monitor HIV, HBV and HCV infections in prisons in order to prevent spreading of these viruses both in jails and in the general population, and to implement effective public health programs that limit the circulation of different genetic forms as well as of viral variants with mutations conferring resistance to treatment.


Assuntos
Coinfecção , Soropositividade para HIV , HIV-1 , Hepatite C , Humanos , Estudos Transversais , HIV-1/genética , Vírus da Hepatite B/genética , Coinfecção/epidemiologia , Filogenia , Hepatite C/complicações , Hepatite C/epidemiologia , Itália/epidemiologia
2.
Tissue Antigens ; 80(1): 36-45, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22494179

RESUMO

Mauritian cynomolgus macaques (MCM) are widely used in human immunodeficiency virus research because of their restricted major histocompatibility complex (MHC) diversity which provides the opportunity to address the influence of host factors on vaccine studies. We herein report the impact of MHC haplotype on the outcome of 21 MCM infections with the CCR5-tropic simian/human immunodeficiency virus (SHIV)(SF162P4cy). MCM were susceptible to SHIV(SF162P4cy) infection as shown by viremia and loss of CD4+ T cells. A significant association between haplotype M7 (class IA, IB, II) and persistent viremia was observed in chronic phase, whereas recombinant class IA haplotype was associated with a reduction of viral RNA during acute infection. Class IB M4 haplotype displayed significantly lower acute phase provirus copy numbers. In addition, statistical analysis indicated a detrimental effect of haplotype M4 (class IA, IB) on the course of infection as indicated by lower CD4+ T-cell levels during chronic infection. A decrease in post-acute phase CD4+ T-cell numbers was also observed in haplotype M2 animals. This is the first report that documents the effects of host MHC class I and II molecules on the SHIV(SF162P4cy) infection in MCM, particularly with regard to the association between recombinant class IA, M4, and M7 haplotypes and the dynamic of viral replication and level of CD4+ T cells.


Assuntos
Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe I/genética , Síndrome de Imunodeficiência Adquirida dos Símios/genética , Vírus da Imunodeficiência Símia/fisiologia , Animais , Linfócitos T CD4-Positivos/patologia , Contagem de Células , Progressão da Doença , Infecções por HIV/genética , Infecções por HIV/imunologia , Haplótipos , Humanos , Macaca fascicularis , Modelos Animais , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/fisiopatologia , Replicação Viral/genética , Replicação Viral/imunologia
3.
Nat Med ; 5(6): 643-50, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10371502

RESUMO

Vaccine strategies aimed at blocking virus entry have so far failed to induce protection against heterologous viruses. Thus, the control of viral infection and the block of disease onset may represent a more achievable goal of human immunodeficiency virus (HIV) vaccine strategies. Here we show that vaccination of cynomolgus monkeys with a biologically active HIV-1 Tat protein is safe, elicits a broad (humoral and cellular) specific immune response and reduces infection with the highly pathogenic simian-human immunodeficiency virus (SHIV)-89.6P to undetectable levels, preventing the CD4+ T-cell decrease. These results may provide new opportunities for the development of a vaccine against AIDS.


Assuntos
Vacinas contra a AIDS/imunologia , Produtos do Gene tat/imunologia , HIV-1/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/terapia , Vacinas contra a AIDS/genética , Animais , Formação de Anticorpos , Linfócitos T CD4-Positivos/virologia , Imunidade Celular , Macaca fascicularis , Vírus da Imunodeficiência Símia/imunologia , Vírus da Imunodeficiência Símia/patogenicidade , Resultado do Tratamento , Fator de Necrose Tumoral alfa/metabolismo , Vacinação , Replicação Viral/imunologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana
4.
Int J Immunopathol Pharmacol ; 21(4): 999-1006, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19144286

RESUMO

Primary effusion lymphomas (PELs) are invariably infected by the human herpesvirus 8 (HHV8)that is present in most PEL cells as latent virus but replicates in a subset of permissive cells to produce infectious progeny. Here we show that productively infected PEL cells release C-type retrovirus-like particles encoding an Mn++-dependent RT activity, which is typical of endogenous retroviruses. Strikingly, C-type particles are produced only in cells showing advanced HHV8 morphogenesis. Phorbol esters, which induce productive HHV8 replication and morphogenesis in PEL cells, increase RLP production. Phosphonoacetic acid, a blocker of HHV8 late gene expression, inhibits the production of C-type particles, whereas neutralizing anti-alphaIFN antibodies, which are known to increase HHV8 assembly, increases C-type particle production. These data suggest that factors expressed in advanced stages of HHV8 reactivation support endogenous C-type particle morphogenesis in PEL cells.


Assuntos
Herpesvirus Humano 8/isolamento & purificação , Linfoma de Efusão Primária/virologia , Vírion , Linhagem Celular , Imunofluorescência , Herpesvirus Humano 8/fisiologia , Humanos , Linfoma de Efusão Primária/patologia , Microscopia Eletrônica de Varredura , Retroviridae/crescimento & desenvolvimento , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Replicação Viral
5.
Clin Exp Rheumatol ; 7(2): 197-202, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2736834

RESUMO

Fifty-six subjects (46 females and 10 males) with signs of Sjögren's Syndrome (SS) have been evaluated for clinical and serological parameters. In 12 subjects such clinical signs were associated with a definite connective tissue disease (secondary SS): Rheumatoid Arthritis (2 cases), Systemic Lupus Erythematosus (4 cases), Progressive Systemic Sclerosis (4 cases), Essential Mixed Cryoglobulinemia (2 cases). All patients underwent a lip biopsy which was evaluated according to the Chisholm-Mason scale. Six out of 56 subjects (10.7%) had a normal salivary gland with few lymphocytes (class I); 5 (10%) had a scattered lymphoid infiltrate containing less than 1 focus/4 mm2 (class II); 36 (64.3%) had one focus/4 mm2 (class III) and, finally, 9 (16%) had more than 1 focus/4 mm2 (class IV). The great majority (91%) of the patients had some abnormalities at the ophthalmological examination (Schirmer test, Break up times, van Bijsterveld score): even those with a class I lip biopsy. Xerostomia was present in 69% of the patients, xerophthalmia in 78%, arthralgias in 78%, parotid swelling in 19%, Raynaud's phenomenon in 16%, recurrent abortion in 9 patients. The prevalence of autoantibodies in the group of primary SS was high: ANA 43.2%, anti-Ha 40%, anti-Ro 12%, anti-phospholipids 52.2%, rheumatoid factor (RF) 45.7%. A decrease of lysozyme concentration in tears and saliva has been demonstrated and a correlation between level of lysozyme and lip-biopsy has been observed.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Autoanticorpos/análise , Síndrome de Sjogren/imunologia , Adulto , Idoso , Cardiolipinas/imunologia , Feminino , Humanos , Imunoglobulina A/análise , Masculino , Pessoa de Meia-Idade , Fator Reumatoide/análise , Glândulas Salivares Menores/imunologia , Glândulas Salivares Menores/patologia , Síndrome de Sjogren/complicações , Síndrome de Sjogren/patologia
6.
Minerva Stomatol ; 26(1): 17-24, 1977.
Artigo em Italiano | MEDLINE | ID: mdl-267801

RESUMO

Defects of the bone margin requiring ostectomy and osteoplasty include hyperostotic processes, formations which, while recalling palatine and mandibular tori, have their own nosological slot. Hyperostosis is characterized by thickening of the cervical margin and is linked by a narrow isthmus to the underlying bone plane; it occurs with greatest frequency in the vestibular region. The personal case, in a man of 52, presented two sausage-shaped protuberances located apically at the alveolar margin in the two left arches. Their removal presented no problem of surgical technique as the hyperostosis had no close links with the underlying bone planes. Histological examination of the fragments showed that the hyperostotic tissue consisted of fascicular bone with an intima vascular component. Two years after the operation, the patient presents no signs of relapse and would appear to be completely cured.


Assuntos
Processo Alveolar/cirurgia , Exostose/cirurgia , Humanos , Masculino , Mandíbula/cirurgia , Maxila/cirurgia , Pessoa de Meia-Idade
9.
Arch Virol ; 153(3): 463-72, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18080858

RESUMO

Simian-human immunodeficiency virus (SHIV) 89.6P is considered to be one of the most pathogenic chimeric viruses in rhesus macaques. However, when crossing from one to another species of monkeys the pathogenicity of this virus may be affected. By using SHIV-89.6P(cy243), a virus obtained by passaging SHIV-89.6P in cynomolgus macaques, we investigated the dynamics of viral replication and the impact of the inoculum size (from 10 up to 50 monkey infectious dose) on the progression of the infection in 22 cynomolgus macaques. SHIV-89.6P(cy243 )caused massive depletion of CD4+ T-cells within 4 weeks of the inoculum, followed by an irreversible immune deficiency in a high proportion of the infected monkeys. This study demonstrates that SHIV-89.6P(cy243) is pathogenic in cynomolgus macaques and that the dynamics of the viral replication and the rate of clinical progression depend on the size of the inoculum. Our findings provide unique and relevant data, particularly with regard to the value of the in vivo titration used to select the most appropriate infectious dose to study the "virus-host" interplay.


Assuntos
HIV/genética , Macaca fascicularis/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/genética , Animais , Contagem de Linfócito CD4 , Progressão da Doença , Genoma Viral , HIV/isolamento & purificação , HIV/patogenicidade , HIV/fisiologia , Humanos , Estimativa de Kaplan-Meier , Mutação , Vírus da Imunodeficiência Símia/isolamento & purificação , Vírus da Imunodeficiência Símia/patogenicidade , Vírus da Imunodeficiência Símia/fisiologia , Carga Viral , Replicação Viral
10.
J Assoc Off Anal Chem ; 67(2): 275-7, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6725196

RESUMO

A method is described for the determination of pentachlorophenol (PCP) in gelatin. The method employs acid and heat to hydrolyze the gelatin matrix, a base partition and wash for separation and cleanup, and a reacidification and extraction with hexane for direct determination of PCP, without preparation of a derivative, using gas chromatography (GC) with a 1% SP- 124ODA liquid phase and a 63Ni electron capture detector. Recoveries averaged 106% for fortifications between 0.02 and 1.0 ppm. The limit of quantitation is 20 ppb. The limit of detection is 4-6 ppb. The method, which has undergone a successful intralaboratory trial, is simple and rapid, and requires only general laboratory reagents and equipment. GC of the acetate derivative of PCP is used for confirmation of identity.


Assuntos
Clorofenóis/análise , Gelatina/análise , Pentaclorofenol/análise , Cromatografia Gasosa/métodos , Contaminação de Alimentos , Pentaclorofenol/isolamento & purificação
11.
J Assoc Off Anal Chem ; 61(4): 877-83, 1978 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-79570

RESUMO

Finfish, shellfish, and crustacean samples are extracted with isopropanol and benzene; the extract is filtered and then concentrated. The extract, dissolved in hexane, is treated with oleum and extracted with aqueous alkali. The aqueous phase is acidified and extracted with petroleum ether-ethyl ether (1 + 1). The Kepone residue is determined by electron capture gas-liquid chromatography (GLC). Recoveries obtained by 8 laboratories from 15 species of finfish fortified at 0.02-0.23 ppm ranged from 37 to 107% with a mean +/- relative standard deviation of 79.4 +/- 14.5%. For oysters fortified at 0.01-0.10 ppm, recoveries range from 63 to 129% with a mean of 78.8 +/- 20.8%. For crustaceans fortified at 0.05-0.26 ppm, recoveries ranged from 52 to 110% with a mean of 78 +/- 16.4%. The approximate limits of quantitation for finfish and for shellfish and crustaceans are 0.02 and 0.05 ppm, respectively, under the GLC conditions used in this study.


Assuntos
Clordecona/análise , Peixes , Inseticidas/análise , Resíduos de Praguicidas/análise , Frutos do Mar/análise , Animais , Cromatografia Gasosa , Cromatografia Líquida , Produtos Pesqueiros/análise
12.
J Virol ; 72(11): 9313-7, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9765481

RESUMO

Human immunodeficiency virus type 1 particle assembly is directed by the Gag polyprotein Pr55(gag), the precursor for the matrix (MA), capsid (CA), and nucleocapsid proteins of the mature virion. We now show that CA sequences N terminal to the major homology region (MHR), which form a distinct domain, are dispensable for particle formation. However, slightly larger deletions which extend into the MHR severely impair particle production. Remarkably, a deletion which removed essentially all MA and CA sequences between the N-terminal myristyl anchor and the MHR reduced the yield of extracellular particles only moderately. Particle formation even exceeded wild-type levels when additional MA sequences, either from the N or the C terminus of the domain, were retained. We conclude that no distinct region between the myristyl anchor and the MHR is required for efficient particle assembly or release.


Assuntos
Produtos do Gene gag/fisiologia , HIV-1/crescimento & desenvolvimento , HIV-1/fisiologia , Fragmentos de Peptídeos/fisiologia , Precursores de Proteínas/fisiologia , Produtos do Gene gag/química , Produtos do Gene gag/genética , HIV-1/genética , Células HeLa , Humanos , Microscopia Eletrônica , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Precursores de Proteínas/química , Precursores de Proteínas/genética , Deleção de Sequência , Transfecção , Replicação Viral/genética , Replicação Viral/fisiologia
13.
J Virol ; 74(14): 6689-94, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10864687

RESUMO

The infection of CD4-negative cells by variants of tissue culture-adapted human immunodeficiency virus type 1 (HIV-1) or HIV-2 strains has been shown to be mediated by the CXCR4 coreceptor. Here we show that two in vitro-established CD4(-)/CCR5(-)/CXCR4(+) human pre-T-cell lines (A3 and A5) can be productively infected by wild-type laboratory-adapted T-cell-tropic HIV-1 and HIV-2 strains in a CD4-independent, CXCR4-dependent fashion. Despite the absence of CCR5 expression, A3 and A5 cells were susceptible to infection by the simian immunodeficiency viruses SIVmac239 and SIVmac316. Thus, at least in A3 and A5 cells, one or more of the chemokine receptors can efficiently support the entry of HIV and SIV isolates in the absence of CD4. These findings suggest that to infect cells of different compartments, HIV and SIV could have evolved in vivo to bypass CD4 and to interact directly with an alternative receptor.


Assuntos
Antígenos CD4/metabolismo , HIV-1/patogenicidade , HIV-2/patogenicidade , Receptores CCR5/metabolismo , Receptores CXCR4/metabolismo , Vírus da Imunodeficiência Símia/patogenicidade , Linfócitos T/virologia , Acetilação , Linhagem Celular , Proteína gp120 do Envelope de HIV/metabolismo , HIV-1/metabolismo , HIV-2/metabolismo , Humanos , Vírus da Imunodeficiência Símia/metabolismo , Linfócitos T/metabolismo
14.
J Virol ; 71(9): 7110-3, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9261445

RESUMO

Human immunodeficiency virus type 1 (HIV-1) incorporates the cellular peptidyl-prolyl cis-trans isomerase cyclophilin A (CyPA), the cytosolic receptor for the immunosuppressant cyclosporin A (CsA). CsA inhibits the incorporation of CyPA and reduces HIV-1 virion infectivity but is inactive against closely related primate lentiviruses that do not interact with CyPA. The incorporation of CyPA into HIV-1 virions is mediated by a specific interaction with a proline-containing, solvent-exposed loop in the capsid (CA) domain of the Gag polyprotein. CsA, which disrupts the interaction with CA, binds at the active site of CyPA. To test whether active-site residues are also involved in the interaction with HIV-1 CA, we used a panel of previously characterized active-site mutants of human CyPA. Expression vectors for epitope-tagged wild-type and mutant CyPA were transfected into COS-gamma cells along with HIV-1 proviral DNA, and the virions produced were analyzed for the presence of tagged proteins. Cotransfection of the wild-type expression vector led to the incorporation of readily detectable amounts of epitope-tagged CyPA into HIV-1 virions. One CyPA mutant with a substantially decreased sensitivity to CsA was incorporated with wild-type efficiency, demonstrating that the requirements for binding to CsA and to HIV-1 CA are not identical. The remaining six CyPA mutants were incorporated with markedly reduced efficiency, providing in vivo evidence that HIV-1 CA interacts with the active site of CyPA.


Assuntos
Isomerases de Aminoácido/metabolismo , Proteínas de Transporte/metabolismo , HIV-1/metabolismo , Isomerases de Aminoácido/química , Isomerases de Aminoácido/genética , Animais , Sítios de Ligação , Células COS , Proteínas de Transporte/química , Proteínas de Transporte/genética , Humanos , Estrutura Molecular , Mutação , Peptidilprolil Isomerase , Vírion/metabolismo
15.
J Virol ; 72(7): 5441-8, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9620999

RESUMO

Inactivation of progeny virions with chimeric virion-associated proteins represents a novel therapeutic approach against human immunodeficiency virus (HIV) replication. The HIV type 1 (HIV-1) Vpr gene product, which is packaged into virions, is an attractive candidate for such a strategy. In this study, we developed Vpr-based fusion proteins that could be specifically targeted into mature HIV-1 virions to affect their structural organization and/or functional integrity. Two Vpr fusion proteins were constructed by fusing to the first 88 amino acids of HIV-1 Vpr the chloramphenicol acetyltransferase enzyme (VprCAT) or the last 18 C-terminal amino acids of the HIV-1 Vpu protein (VprIE). These Vpr fusion proteins were initially designed to quantify their efficiency of incorporation into HIV-1 virions when produced in cis from the provirus. Subsequently, CD4+ Jurkat T-cell lines constitutively expressing the VprCAT or the VprIE fusion protein were generated with retroviral vectors. Expression of the VprCAT or the VprIE fusion protein in CD4+ Jurkat T cells did not interfere with cellular viability or growth but conferred substantial resistance to HIV replication. The resistance to HIV replication was more pronounced in Jurkat-VprIE cells than in Jurkat-VprCAT cells. Moreover, the antiviral effect mediated by VprIE was dependent on an intact p6(gag) domain, indicating that the impairment of HIV-1 replication required the specific incorporation of Vpr fusion protein into virions. Gene expression, assembly, or release was not affected upon expression of these Vpr fusion proteins. Indeed, the VprIE and VprCAT fusion proteins were shown to affect the infectivity of progeny virus, since HIV virions containing the VprCAT or the VprIE fusion proteins were, respectively, 2 to 3 times and 10 to 30 times less infectious than the wild-type virus. Overall, this study demonstrated the successful transfer of resistance to HIV replication in tissue cultures by use of Vpr-based antiviral genes.


Assuntos
Produtos do Gene vpr/fisiologia , HIV-1/fisiologia , Proteínas Recombinantes de Fusão/fisiologia , Vírion/fisiologia , Humanos , Células Jurkat , Replicação Viral , Produtos do Gene vpr do Vírus da Imunodeficiência Humana
16.
J Med Primatol ; 22(2-3): 110-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8411103

RESUMO

In cynomolgus monkeys, we compared two human-derived SIVmac251 whole virus vaccines, a long vs short immunization schedule, and two different challenge viruses. Both vaccines induced protection after challenge with human-derived SIVmac251/32H. There was no difference between the two schedules of immunization. Seven monkeys, five of which were protected following the first challenge, were reboosted and rechallenged with monkey-derived SIVmac251, but no protection was observed. The titers of anti-human cell or -SIV neutralizing antibodies were not related to protection.


Assuntos
Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vírus da Imunodeficiência Símia/imunologia , Vacinas Virais/farmacologia , Animais , Anticorpos Antivirais/biossíntese , Sequência de Bases , Linhagem Celular , DNA Viral/genética , Feminino , Humanos , Esquemas de Imunização , Técnicas In Vitro , Macaca fascicularis , Masculino , Dados de Sequência Molecular , Testes de Neutralização , Gravidez , Provírus/genética , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/genética , Vírus da Imunodeficiência Símia/crescimento & desenvolvimento , Vacinas de Produtos Inativados/isolamento & purificação , Vacinas de Produtos Inativados/farmacologia , Vacinas Virais/isolamento & purificação , Cultura de Vírus
17.
J Med Primatol ; 21(2-3): 91-8, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1433272

RESUMO

Five pregnant (two to three and one-half months) Macaca fascicularis seroconverted following immunization with sucrose-gradient purified and formalin-inactivated whole simian immunodeficiency virus (SIVmac251). No untoward effects on fetal maturation were observed during the immunization of the mothers. Antibodies to SIVmac251 (also those with in vitro neutralizing activity) were passively transferred to the offspring but disappeared within two to six months after birth. Antibodies to env glycoprotein (gp130) lasted longer than those against viral gag proteins (p26,p60).


Assuntos
Anticorpos Antivirais/biossíntese , Imunidade Materno-Adquirida , Macaca fascicularis , Vírus da Imunodeficiência Símia/imunologia , Vacinas Virais/imunologia , Animais , Desenvolvimento Embrionário e Fetal , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Imunização Secundária/veterinária , Gravidez , Complicações Infecciosas na Gravidez/prevenção & controle , Complicações Infecciosas na Gravidez/veterinária , Resultado da Gravidez/veterinária , Ensaio de Radioimunoprecipitação , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vacinação/veterinária , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Vacinas Virais/efeitos adversos
18.
J Gen Virol ; 73 ( Pt 12): 3087-97, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1335022

RESUMO

Two immature T cell lines (FT1 and FT4) were established after in vitro cloning of peripheral blood lymphocytes (PBLs) from an asymptomatic human immunodeficiency virus type 1 (HIV-1) seropositive, human T cell-lymphotropic virus type 1 seronegative homosexual subject. Although derived from a limiting dilution cell cloning assay, these cell lines were not recloned for this study. Their growth was independent of exogenous interleukin-2. Both cell lines were able to form colonies when cloned in agar, but failed to form solid tumours when injected into nude mice. FT lines belong to the very immature T cell lineage as they exhibit rearranged TCR genes but no expression of T cell membrane antigens, including CD2, CD3, CD4, CD6, CD7 and CD8. They also contain an HIV-1 genome that was detected only in an extra-chromosomal DNA form, even after several passages in vitro. The presence of unintegrated viral DNA was also detected by polymerase chain reaction analysis in the same sample of fresh uncultured PBLs. Furthermore, despite the absence of CD4 expression, both T cell lines were susceptible to CD4-independent HIV-1 superinfection (lack of superinfection inhibition in the presence of OKT4A monoclonal antibodies).


Assuntos
DNA Viral/genética , HIV-1/genética , Linfócitos T/microbiologia , Adulto , Sequência de Bases , Antígenos CD4/análise , Herança Extracromossômica , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Rearranjo Gênico do Linfócito T , Genes , Soropositividade para HIV/genética , Soropositividade para HIV/microbiologia , Herpesvirus Humano 4/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Interleucina-2/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos/química , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/citologia
19.
J Virol ; 72(2): 1652-6, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9445072

RESUMO

The human CXCR-4 molecule serves as a second receptor for primary, T-cell-tropic, and laboratory-adapted human immunodeficiency virus type 1 (HIV-1) isolates. Here we show that murine CXCR-4 can support the entry of some of these HIV-1 isolates. Differences between mouse and human CXCR-4 in the ability to function as an HIV-1 receptor are determined by sequences in the second extracellular loop of the CXCR-4 protein.


Assuntos
HIV-1/fisiologia , Receptores de Quimiocinas/fisiologia , Receptores Virais/fisiologia , Linfócitos T/virologia , Animais , Humanos , Camundongos , Receptores CCR4 , Replicação Viral
20.
Clin Exp Immunol ; 127(2): 321-30, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11876757

RESUMO

In this paper we addressed the expression of the HIV co-receptors CXCR-4 and CCR-5 in human thymocytes by phenotypic, molecular and functional approaches. Cytofluorimetric analysis disclosed that CXCR-4 was constitutively expressed by freshly isolated thymocytes (~10 000 molecules/cell in about 30% of thymocytes); the receptor was endowed with functional activity, as it mediated polarization, migration and intracellular Ca2+ increase in response to its ligand, SDF-1. On the contrary, CCR-5 expression in freshly isolated thymocytes was significantly lower (<4000 molecules/cell in less than 5% of the cells), and no functional response to CCR-5 agonists could be documented. Northern blot analysis of freshly isolated thymocytes showed high CXCR-4 mRNA levels, whereas the message for CCR-5 was barely detectable. On the other hand, a modest increase in the expression of CCR-5 was associated with in vitro thymocyte stimulation, and CCR-5 density at the cell surface attained CXCR-4 figures in most cases. None the less, no functional response to CCR-5 agonists could be documented in in vitro stimulated thymocytes. In vitro infection of thymocytes by CAT-expressing recombinant HIV bearing the envelope glycoproteins from different isolates showed that T-tropic strains, which use CXCR-4 as a co-receptor, were more efficient in infecting thymocytes than M-tropic strains, which preferentially use CCR-5. Altogether, these data indicate that expression of the major co-receptors involved in infection by M-tropic HIV strains is very poor in human thymocytes, and would suggest that thymocyte infection by M-tropic HIV strains may be a rare event in vivo.


Assuntos
Receptores CCR5/biossíntese , Receptores CXCR4/biossíntese , Receptores de HIV/biossíntese , Subpopulações de Linfócitos T/efeitos dos fármacos , Northern Blotting , Cálcio/metabolismo , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/imunologia , Células Cultivadas/metabolismo , Quimiocina CCL4 , Quimiocina CCL5/farmacologia , Quimiocina CXCL12 , Quimiocinas CXC/farmacologia , Pré-Escolar , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína gp120 do Envelope de HIV/metabolismo , HIV-1/classificação , HIV-1/fisiologia , Humanos , Imunofenotipagem , Lactente , Recém-Nascido , Transporte de Íons/efeitos dos fármacos , Ativação Linfocitária , Proteínas Inflamatórias de Macrófagos/farmacologia , Masculino , Receptores CCR5/efeitos dos fármacos , Receptores CCR5/genética , Receptores CCR5/fisiologia , Receptores CXCR4/efeitos dos fármacos , Receptores CXCR4/genética , Receptores CXCR4/fisiologia , Receptores de HIV/efeitos dos fármacos , Receptores de HIV/genética , Receptores de HIV/fisiologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Timo/citologia
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