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1.
J Infect Dis ; 219(11): 1749-1754, 2019 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-30715363

RESUMEN

Disease progression of human immunodeficiency virus type 1 (HIV-1) is delayed by HIV type 2 (HIV-2) in individuals with dual HIV-1/HIV-2 infection. The protective mechanisms, however, are still to be revealed. In the current study we examined type-specific and cross-reactive antibody-dependent cellular cytotoxicity (ADCC) in HIV-1 and HIV-2 monoinfection or dual infection. Of note, intertype cross-reactive antibodies that mediated HIV-1 envelope glycoprotein (Env)-targeted ADCC were frequently identified in HIV-2-infected individuals. Furthermore, the magnitude of HIV-1 cross-reactive ADCC activity during HIV-2 infections depended on the HIV-1 Env origin and was associated with the duration of infection. These results suggest that preexisting antibodies against HIV-2, which mediate intertype ADCC, might contribute to control of HIV-1 during dual infection.


Asunto(s)
Citotoxicidad Celular Dependiente de Anticuerpos/inmunología , Reacciones Cruzadas/inmunología , Glicoproteínas/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , VIH-2/inmunología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Anticuerpos Neutralizantes/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/virología , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/virología , Humanos
2.
Retrovirology ; 7: 46, 2010 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-20482865

RESUMEN

BACKGROUND: There have been no previous studies of the long-term survival and temporal changes in plasma viral load among HIV-2 infected subjects. METHODS: 133 HIV-2 infected and 158 HIV-uninfected subjects from a rural area in North-west Guinea-Bissau, West Africa were enrolled into a prospective cohort study in 1991 and followed-up to mid-2009. Data were collected on four occasions during that period on HIV antibodies, CD4% and HIV-2 plasma viral load. RESULTS: Median age (interquartile range [IQR]) of HIV-2 infected subjects at time of enrollment was 47 (36, 60) years, similar to that of HIV-uninfected control subjects, 49 (38, 62) (p = 0.4). Median (IQR) plasma viral load and CD4 percentage were 347 (50, 4,300) copies/ml and 29 (22, 35) respectively.Overall loss to follow-up to assess vital status was small, at 6.7% and 6.3% for HIV-2 infected and uninfected subjects respectively. An additional 17 (12.8%) and 16 (10.1%) of HIV-2 infected and uninfected subjects respectively were censored during follow-up due to infection with HIV-1. The mortality rate per 100 person-years (95% CI) was 4.5 (3.6, 5.8) among HIV-2 infected subjects compared to 2.1 (1.6, 2.9) among HIV-uninfected (age-sex adjusted rate ratio 1.9 (1.3, 2.8, p < 0.001) representing a 2-fold excess mortality rate associated with HIV-2 infection.Viral load measurements were available for 98%, 78%, 77% and 61% HIV-2 infected subjects who were alive and had not become super-infected with HIV-1, in 1991, 1996, 2003 and 2006 respectively. Median plasma viral load (RNA copies per ml) (IQR) did not change significantly over time, being 150 (50, 1,554; n = 77) in 1996, 203 (50, 2,837; n = 47) in 2003 and 171 (50, 497; n = 31) in 2006. Thirty seven percent of HIV-2 subjects had undetectable viraemia (<100 copies/ml) at baseline: strikingly, mortality in this group was similar to that of the general population. CONCLUSIONS: A substantial proportion of HIV-2 infected subjects in this cohort have stable plasma viral load, and those with an undetectable viral load (37%) at study entry had a normal survival rate. However, the sequential laboratory findings need to be interpreted with caution given the number of individuals who could not be re-examined.


Asunto(s)
Infecciones por VIH/mortalidad , Infecciones por VIH/virología , VIH-2/aislamiento & purificación , Plasma/virología , Carga Viral , Adulto , Animales , Recuento de Linfocito CD4 , Estudios de Cohortes , Femenino , Guinea Bissau , Anticuerpos Anti-VIH/sangre , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Análisis de Supervivencia
3.
Trans R Soc Trop Med Hyg ; 112(4): 175-180, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29733405

RESUMEN

Background: Human T-cell leukaemia/lymphoma virus type 1 (HTLV-1) was the first human retrovirus discovered and there is an estimate of 15-20 million infected worldwide. Endemic areas are Japan, West Africa, Central Africa, South America, the Caribbean, Middle East, Australia and the Pacific Islands. In Guinea-Bissau, adult HTLV-1 prevalence is 2-3%, and higher among HIV-infected patients. Materials and methods: Blood samples were collected in a recent HIV/HTLV survey in Bissau, the capital of Guinea-Bissau. Initially, participants were tested for HTLV serologically. The p24 and LTR regions of the proviral genome were then attempted sequenced. Sequences were analysed phylogenetically and compared with reference sequences for HTLV-1. Results: A total of 3% (78/2583) participants were positive on chemiluminesent assay, six additional samples came from another study. Of the 84 seropositive participants we successfully performed sequencing on samples, from 66 participants, 17 were positive for LTR only, one for p24 only and 48 for both. Sequences were in subgroup D of HTLV-1a cosmopolitan, while HTLV-1g was present in one participant. Conclusion: HTLV-1a subgroup D and, to a lesser extent HTLV-1g, is present in Guinea-Bissau and sequences are very similar, especially within households. Presence of HTLV-1g indicates monkey-to-man zoonotic events and at least two circulating HTLV strains in Guinea-Bissau. New sequences accession numbers: MG387979-MG388043 for LTR and MG388044-MG388092 for p24.


Asunto(s)
Infecciones por Deltaretrovirus/transmisión , Anticuerpos Anti-HTLV-I/inmunología , Infecciones por HTLV-I/transmisión , Virus Linfotrópico T Tipo 1 Humano/genética , Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Virus Linfotrópico T Tipo 1 de los Simios/genética , Zoonosis/epidemiología , Adolescente , Adulto , Animales , Portador Sano , Niño , Infecciones por Deltaretrovirus/genética , Infecciones por Deltaretrovirus/inmunología , Femenino , Variación Genética , Guinea Bissau/epidemiología , Infecciones por HTLV-I/genética , Infecciones por HTLV-I/inmunología , Haplorrinos , Humanos , Masculino , Persona de Mediana Edad , Filogenia , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Estudios Seroepidemiológicos , Carga Viral , Adulto Joven , Zoonosis/genética , Zoonosis/inmunología
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