RESUMEN
BACKGROUND: Epstein-Barr Virus (EBV) is involved in a wide range of malignancies, particularly in immunocompromised subjects. In Africa, EBV primary infection occurs during early childhood, but little is known about the EBV load in Human Immunodeficiency Virus type 1 (HIV-1)-infected children. METHODS: Blood samples from 213 HIV-1-infected children, 140 of whom were receiving antiretroviral therapy (ART), were collected at the Nsambya Hospital in Kampala, Uganda, and obtained for dried blood spot analysis. Nucleic acids were extracted and analyzed for quantification of EBV types 1 and 2; 16S ribosomal DNA (rDNA), a marker of microbial translocation; and HIV-1 RNA. RESULTS: Ninety-two of 140 children (66%) receiving ART and 57 of 73 ART-naive children (78%) had detectable EBV DNA levels. Coinfection with both EBV types was less frequent in ART-treated children than in ART-naive children (odds ratio, 0.54 [95% confidence interval {CI}, .30-.98]; P = .042). Mean EBV DNA levels (±standard deviation) were lower in the former (3.99 ± 0.59 vs 4.22 ± 0.54 log10 copies/mL; P = .006) and tended to be inversely associated with ART duration. EBV DNA levels were higher in children with an HIV-1 RNA load of > 3 log10 copies/mL of blood (regression coefficient, 0.32 [95% CI, .05-.59]; P = .020) and correlated with circulating 16S rDNA levels (rs = 0.25 [95% CI, .02-.46]; P = .031). CONCLUSIONS: These findings suggest that ART, by limiting HIV-1 replication, microbial translocation, and related immune activation, prevents superinfection with both EBV types and keeps EBV viremia down, thus potentially reducing the risk of EBV-associated lymphomas.
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Infecciones por Virus de Epstein-Barr/virología , Infecciones por VIH/complicaciones , VIH-1/aislamiento & purificación , Herpesvirus Humano 4/aislamiento & purificación , Carga Viral , Adolescente , Fármacos Anti-VIH/uso terapéutico , Niño , Preescolar , ADN Viral/aislamiento & purificación , Femenino , Infecciones por VIH/sangre , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Lactante , MasculinoRESUMEN
Correlations between clinical/immunological treatment failure and viral load (VL) detected by dried blood spot (DBS) sampling were explored in HIV-1-infected children in Uganda. Of 104 children on combined antiretroviral treatment (cART), 12.5% experienced clinical and/or immunological failure, while 28.8%, 44.2%, and 26.9% had VLs of <1,000, 1,000 to 5,000, and >5,000 copies/ml, respectively. Clinical/immunological failure poorly predicted virological failure.
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Sangre/virología , Desecación/métodos , Infecciones por VIH/virología , VIH-1/aislamiento & purificación , Manejo de Especímenes/métodos , Carga Viral/métodos , Antirretrovirales/uso terapéutico , Terapia Antirretroviral Altamente Activa , Niño , Preescolar , Estudios de Cohortes , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Humanos , Masculino , Sensibilidad y Especificidad , Insuficiencia del Tratamiento , UgandaRESUMEN
Variability in the susceptibility to HIV-1 infection and disease progression depends on both virus and host determinants. Some exposed individuals remain HIV-1-uninfected and HIV-1-infected subjects develop disease at varying intervals with a small percentage remaining long-term non-progressors. As innate immunity is the earliest response to microbial entry and injury, host factors that impact innate immunity may play a role in viral infectivity and pathogenesis. In the pediatric population the interactions between the virus and the host may be of particular relevance due to the still developing adaptive immune system. Data indicate that genetic variants of defensins and Toll-Like Receptors (TLRs), key elements of innate immunity, play a role in mother-to-child transmission (MTCT) of HIV-1, and in the outcome of pediatric HIV-1 disease. Although the mechanisms by which these genetic variants influence HIV-1 interactions with the host are still largely unknown, defensins and TLRs, along with their link with regulatory T cells (Tregs), may play a critical role in the onset and persistence of immune activation, a hallmark of HIV-1 disease.
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Progresión de la Enfermedad , Infecciones por VIH/inmunología , VIH-1/inmunología , Interacciones Huésped-Patógeno , Inmunidad Innata , Niño , Susceptibilidad a Enfermedades/inmunología , Infecciones por VIH/transmisión , Infecciones por VIH/virología , VIH-1/patogenicidad , Humanos , Polimorfismo de Nucleótido Simple , Linfocitos T Reguladores/inmunología , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/inmunología , beta-Defensinas/genética , beta-Defensinas/inmunologíaRESUMEN
Background: The immune response plays a pivotal role in dictating the clinical outcome in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected adults, but it is still poorly investigated in the pediatric population. Methods: Of 209 enrolled subjects, 155 patients were confirmed by PCR and/or serology as having coronavirus disease 2019 (COVID-19). Blood samples were obtained at a median of 2.8 (interquartile, 2.1-3.7) and 6.1 (5.3-7.2) months after baseline (symptom onset and/or first positive virus detection). The immune profiles of activation, senescence, exhaustion, and regulatory cells were analyzed by flow cytometry. Neutralizing antibodies (nAbs) were detected by a plaque reduction neutralization test. In available nasopharyngeal swabs at baseline, SARS-CoV-2 levels were quantified by digital droplet PCR (ddPCR). Results: Overall, COVID-19 patients had higher levels of immune activation, exhaustion, and regulatory cells compared to non-COVID-19 subjects. Within the COVID-19 group, activated and senescent cells were higher in adults than in children and inversely correlated with the nAbs levels. Conversely, Tregs and Bregs regulatory cells were higher in COVID-19 children compared to adults and positively correlated with nAbs. Higher immune activation still persisted in adults after 6 months of infection, while children maintained higher levels of regulatory cells. SARS-CoV-2 levels did not differ among age classes. Conclusions: Adults displayed higher immune activation and lower production of anti-SARS-CoV-2 nAbs than children. The different immune response was not related to different viral load. The higher expression of regulatory cells in children may contribute to reduce the immune activation, thus leading to a greater specific response against the virus.
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Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Infecciones Asintomáticas , Linfocitos B Reguladores/inmunología , COVID-19/patología , Linfocitos T Reguladores/inmunología , Adulto , Niño , Preescolar , Citocinas/sangre , Femenino , Humanos , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Moléculas de Patrón Molecular Asociado a Patógenos/sangre , Estudios Prospectivos , SARS-CoV-2/inmunología , Índice de Severidad de la Enfermedad , Carga Viral/inmunologíaRESUMEN
BACKGROUND: Toll-like receptors (TLRs) recognize pathogen-associated molecular patterns and play a crucial role in the host's innate immune response. Genetic variations in TLR genes may influence host-viral interactions and might impact upon the risk of mother-to-child transmission (MTCT) of Human Immunodeficiency Virus type 1 (HIV-1). The aim of this study was to investigate the influence of genetic variants of TLR 9 gene on MTCT. METHODS: Three hundred children (118 HIV-1-infected and 182 HIV-1-uninfected) born to HIV-1-infected mothers were studied. Single nucleotide polymorphisms (SNPs) NM_017442.2: c.4-44G > A (rs352139) and c.1635A > G (rs352140) of the TLR9 gene were genotyped by TaqMan allelic discrimination assay. Statistical analyses were performed using SNPStats program. RESULTS: When considered separately, neither of the two SNPs was significantly associated with risk of HIV-1 infection. However, the [A;A] and [G;G] haplotypes were associated with a higher risk of HIV-1 infection compared to the prevalent [G;A] haplotype [odds ratio (OR) = 3.16, 95% confidence interval (CI) 1.24-8.03, p = 0.016, and OR = 5.54, 95% CI 1.76-17.50, p = 0.004, respectively]. CONCLUSIONS: Overall, results demonstrate a significant correlation between specific genetic variants of the TLR9 gene and risk of MTCT of HIV-1, thus confirming a critical role of innate immunity in perinatal HIV-1 infection. Strategies aimed at modulating innate immunity might be useful for future treatment of pediatric HIV-1 infection and AIDS.
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Infecciones por VIH/genética , Infecciones por VIH/transmisión , VIH-1/fisiología , Transmisión Vertical de Enfermedad Infecciosa , Polimorfismo de Nucleótido Simple/genética , Receptor Toll-Like 9/genética , Femenino , Frecuencia de los Genes/genética , Predisposición Genética a la Enfermedad , Haplotipos/genética , HumanosRESUMEN
Despite the widespread use of molecular biology techniques, standardized methods for the measurement of HIV-1 proviral DNA are currently lacking and several discordant results are still present in different studies. To assess the clinical meaning of the proviral DNA load, a study group comprising seven different laboratories was set up to standardize a HIV-1 proviral DNA quantification method able to assess the DNA proviral load of the most relevant circulating HIV-1 subtypes. Reference samples (24 cellular samples infected with HIV-1 clade B, and 40 samples of peripheral blood mononuclear cells containing different concentrations of plasmids expressing different HIV-1 clades) were distributed and tested blindly. All laboratories employed hTERT gene as housekeeping gene and primers within the gag gene to quantify different HIV-1 clades. Inter-laboratory results did not differ statistically but showed only minor variations concerning HIV-1 DNA amounts and different HIV clades, with a good agreement among the laboratories participating in the study. Since test standardization represents a key step for future application in clinical practice, further studies of the patients' samples are in progress to establish the real meaning and utility of the proviral DNA load for clinical management of HIV-1 infected patients.
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ADN Viral/análisis , Infecciones por VIH/virología , VIH-1/aislamiento & purificación , Reacción en Cadena de la Polimerasa/normas , Provirus/aislamiento & purificación , Carga Viral/normas , Línea Celular , VIH-1/genética , Humanos , Italia , Provirus/genética , Sensibilidad y Especificidad , Telomerasa/genética , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/genéticaRESUMEN
Chronic HIV-infected children suffer from premature aging and aging-related diseases. Viral replication induces an ongoing inflammation process, with the release of pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs), the activation of the immune system, and the production of proinflammatory cytokines. Although combined highly active antiretroviral therapy (ART) has significantly modified the natural course of HIV infection, normalization of T and B cell phenotype is not completely achievable; thus, many HIV-infected children display several phenotypical alterations, including higher percentages of activated cells, that favor an accelerated telomere attrition, and higher percentages of exhausted and senescent cells. All these features ultimately lead to the clinical manifestations related to premature aging and comorbidities typically observed in older general population, including non-AIDS-related malignancies. Therefore, even under effective treatment, the premature aging process of HIV-infected children negatively impacts their quality and length of life. This review examines the available data on the impact of HIV and ART on immune and biological senescence of HIV-infected children.
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Envejecimiento/inmunología , Senescencia Celular/inmunología , Infecciones por VIH/fisiopatología , VIH-1/fisiología , Efectos Tardíos de la Exposición Prenatal , Terapia Antirretroviral Altamente Activa , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , EmbarazoRESUMEN
In our previous study, we found that low thymic output and short telomere length were associated with a higher risk of tumor in elderly cancer patients. Here, we aimed to examine in depth the impact of immunological and biological senescence and immune activation on disease outcome in elderly patients with colorectal cancer (CRC).Peripheral blood samples from 81 CRC patients were studied for immune activation, immune senescence and recent thymic emigrant(RTE) CD4 and CD8 cells by flow cytometry. T-cell receptor rearrangement excision circle (TREC) levels and telomere lengths were measured by real-time PCR. Plasma levels of microbial translocation markers, LPS and sCD14, were quantified by ELISA. While TREC levels and telomere length were not prognostic of disease outcome, high percentages of immune senescent and immune activated CD8 cells were associated with a higher risk of a negative event (relapse, progression, or death) in all studied patients and disease relapse in I-III staged patients. Levels of sCD14 and LPS were higher in patients who will experience a negative event than in patients who will not. In conclusion, in elderly CRC patients higher immunological senescence and immune activation negatively impact the disease outcome; how these characteristics influence the antineoplastic treatments remains to be investigated.
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Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Neoplasias Colorrectales/inmunología , Anciano , Anciano de 80 o más Años , Biomarcadores , Femenino , Citometría de Flujo , Humanos , Masculino , TelómeroRESUMEN
BACKGROUND: Perinatal HIV-1 infection is acquired in the milieu of a developing immune system, leading to high levels of uncontrolled viral replication. Few data have been reported that address the viral dynamics and immunological response in infants who initiated aggressive antiretroviral therapy (ART) shortly after birth. METHODS: Six HIV-1-infected infants who started ART within 3 months of age were studied. The median followup was 61 months. Plasma HIV-1 RNA, cell-associated HIV-1 DNA, unspliced and multiply spliced HIV-1 mRNAs, HIV-1 antibodies, and CD4+ and CD8+ T-cell subsets were assessed in sequential peripheral blood samples. HIV-1 cellular immune response was measured by EliSpot assay. RESULTS: All children showed a decline in plasma viraemia to undetectable levels. HIV-1 DNA persisted in four children, but only two of these had detectable HIV-1 mRNA. All viral parameters remained persistently negative in two children. Only two children produced HIV-1 antibodies, while the others, after having lost maternal antibodies, remained seronegative. No HIV-1 cellular immune response was observed in any child. Therapy interruption was performed in two children: one HIV-1-seropositive and one HIV-1-seronegative with persistently undetectable levels of all viral parameters. Rebound of HIV-1 plasma viraemia in the seronegative child was more rapid and higher than that observed in the seropositive child. CONCLUSIONS: Early ART treatment in infants modifies the natural course of infection by controlling HIV-1 replication and reducing viral load to below the threshold levels required for onset of HIV-1 immune response, but does not prevent the establishment of a reservoir of latently infected cells that precludes virus eradication.
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Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , VIH-1/efectos de los fármacos , VIH-1/inmunología , Fármacos Anti-VIH/administración & dosificación , Linfocitos T CD4-Positivos , Preescolar , Infecciones por VIH/virología , VIH-1/fisiología , Humanos , Lactante , Transmisión Vertical de Enfermedad Infecciosa , ARN Mensajero/aislamiento & purificación , ARN Viral/sangreRESUMEN
OBJECTIVES: Although monotherapy (mART) effectiveness in maintaining viral suppression and CD4 cell count has been extensively examined in HIV-1-infected patients, its impact on HIV-1 reservoir, immune activation, microbial translocation and co-infection with Epstein-Barr Virus (EBV) is unclear. METHODS: This retrospective study involved 32 patients who switched to mART; patients were studied at baseline, 48 and 96 weeks after mART initiation. Thirty-two patients who continued combined antiretroviral therapy (cART) over the same period of time were included in the study. Markers of HIV-1 reservoir (HIV-1 DNA and intracellular HIV-1 RNA) were quantified by real-time PCR. Markers of T-(CD3+CD8+CD38+) and B-(CD19+CD80/86+ and CD19+CD10-CD21lowCD27+) cell activation were evaluated by flow cytometry. Plasma levels of microbial translocation markers were quantified by real-time PCR (16S ribosomal DNA and mitochondrial [mt]DNA) or by ELISA (LPS and sCD14). EBV was typed and quantified by multiplex real-time PCR. RESULTS: At baseline, no differences were found between mART and cART groups. Three (10%) mART-treated patients had a virological failure vs none in the cART group. Levels of HIV-1 DNA, intracellular HIV-1 RNA and EBV-DNA remained stable in the mART group, while decreased significantly in the cART group. Percentages of T- and B-activated cells significantly increased in the mART-treated patients, while remained at low levels in the cART-treated ones (p = 0.014 and p<0.001, respectively). Notably, levels of mtDNA remained stable in the cART group, but significantly rose in the mART one (p<0.001). CONCLUSIONS: Long-term mART is associated with higher levels of T- and B-cell activation and, conversely to cART, does not reduce the size of HIV-1 reservoir and EBV co-infection.
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Fármacos Anti-VIH/uso terapéutico , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por VIH/tratamiento farmacológico , Adulto , Terapia Antirretroviral Altamente Activa , Linfocitos B/citología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Coinfección/patología , Coinfección/virología , ADN Mitocondrial/metabolismo , ADN Viral/análisis , ADN Viral/metabolismo , Infecciones por Virus de Epstein-Barr/inmunología , Infecciones por Virus de Epstein-Barr/virología , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/genética , VIH-1/aislamiento & purificación , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Leucocitos Mononucleares/virología , Activación de Linfocitos , Masculino , Persona de Mediana Edad , ARN Viral/análisis , ARN Viral/metabolismo , Estudios Retrospectivos , Linfocitos T/citología , Linfocitos T/inmunología , Linfocitos T/metabolismoRESUMEN
OBJECTIVE: Several pieces of evidence indicate that HIV-infected adults undergo premature aging. The effect of HIV and antiretroviral therapy (ART) exposure on the aging process of HIV-infected children may be more deleterious since their immune system coevolves from birth with HIV. DESIGN: Seventy-one HIV-infected (HIV+), 65 HIV-exposed-uninfected (HEU), and 56 HIV-unexposed-uninfected (HUU) children, all aged 0-5 years, were studied for biological aging and immune senescence. METHODS: Telomere length and T-cell receptor rearrangement excision circle levels were quantified in peripheral blood cells by real-time PCR. CD4 and CD8 cells were analysed for differentiation, senescence, and activation/exhaustion markers by flow cytometry. RESULTS: Telomere lengths were significantly shorter in HIV+ than in HEU and HUU children (overall, Pâ<â0.001 adjusted for age); HIV+ ART-naive (42%) children had shorter telomere length compared with children on ART (Pâ=â0.003 adjusted for age). T-cell receptor rearrangement excision circle levels and CD8 recent thymic emigrant cells (CD45RACD31) were significantly lower in the HIV+ than in control groups (overall, Pâ=â0.025 and Pâ=â0.005, respectively). Percentages of senescent (CD28CD57), activated (CD38HLA-DR), and exhausted (PD1) CD8 cells were significantly higher in HIV+ than in HEU and HUU children (Pâ=â0.004, Pâ<â0.001, and Pâ<â0.001, respectively). Within the CD4 cell subset, the percentage of senescent cells did not differ between HIV+ and controls, but programmed cell death receptor-1 expression was upregulated in the former. CONCLUSIONS: HIV-infected children exhibit premature biological aging with accelerated immune senescence, which particularly affects the CD8 cell subset. HIV infection per se seems to influence the aging process, rather than exposure to ART for prophylaxis or treatment.
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Envejecimiento Prematuro , Infecciones por VIH/patología , Fenómenos del Sistema Inmunológico , Biomarcadores/análisis , Linfocitos T CD4-Positivos/química , Linfocitos T CD4-Positivos/fisiología , Linfocitos T CD8-positivos/química , Linfocitos T CD8-positivos/fisiología , Diferenciación Celular , Senescencia Celular , Preescolar , Femenino , Reordenamiento Génico , Humanos , Lactante , Leucocitos Mononucleares/fisiología , Masculino , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Antígenos de Linfocitos T/genética , Acortamiento del TelómeroRESUMEN
The long-term impact of highly active antiretroviral therapy (HAART) in AIDS patients with Kaposi's sarcoma (KS) was evaluated in 22 consecutive, HAART-naïve KS patients attending a single Italian referral centre for HIV/AIDS. Clinical, virologic and immunologic responses to HAART were assessed at baseline and every three months during the follow-up. Peripheral blood mononuclear cell (PBMC)-associated human herpesvirus 8 (HHV-8) load was also evaluated by real-time PCR in 13 patients with durable clinical KS complete response (CR). In a median follow-up of 40 months (range 17-78), the KS overall clinical response rate was 91%: 18 complete and 2 partial responses were achieved, and two patients experienced disease progression. CR persisted in all 18 patients, including the 5 poor-risk KS patients in whom CR lasted for > 60 months, and was significantly linked to an increase in CD4+ cell counts and a drop in HIV-1-RNA copies. Compared to baseline levels, a decrease in PBMC HHV-8 load was observed at CR, and a significant further reduction was found at the end of follow-up. In this monocentric study, AIDS-KS patients treated with HAART showed high clinical response rate. Patients with CR showed a prolonged remission, lasting more than 5 years in a group of poor-risk patients, and a persistent reduction in circulating HHV-8-infected cells. These findings highlight that HAART deeply modifies the natural history of this tumour in AIDS patients, and that this long-lasting approach may be considered a first-line treatment for the majority of HIV-1-infected patients developing KS.
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Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa , Sarcoma de Kaposi/tratamiento farmacológico , Adulto , Recuento de Linfocito CD4 , ADN Viral/sangre , Estudios de Seguimiento , VIH-1/efectos de los fármacos , VIH-1/genética , Herpesvirus Humano 8/efectos de los fármacos , Herpesvirus Humano 8/genética , Humanos , Masculino , Persona de Mediana Edad , ARN Viral/sangre , Factores de Tiempo , Resultado del TratamientoRESUMEN
A body of evidence indicates that a threshold level of the virus is required to establish systemic and persistent HIV infection in the host and that this level depends on virus-host interactions. Mother-to-child transmission (MTCT) of HIV is the main source of paediatric HIV infection and occurs when the host's immune system is still developing. Thus, innate resistance and immunity, rather than adaptive immune response, may be the main drivers in restricting the establishment of HIV reservoirs and the long-lived persistence of HIV infection in infants. Genetic variations in HIV co-receptors and their ligands, as well as in Toll-like receptors and defensins, key elements of innate immunity, have been demonstrated to influence the risk of perinatal HIV infection and disease progression in HIV-infected infants. Early treatments with combined antiretroviral therapy (cART) restrict paediatric infection by reducing the level of the transmitted/infecting virus to below the threshold required for the onset of immune response to the virus and also significantly reduce HIV reservoirs. However, despite long periods with no signs and symptoms of HIV infection, all early cART-treated children who later discontinued cART had a rebound of HIV, except for one case in whom a period of viral remission occurred. Which parameters predict viral remission or viral rebound after cART discontinuation? Could early cART prevent rather than just reduce the establishment of viral reservoirs? And, if so, how? Answers to these questions are also important in order to optimise the use of early cART in infants at high risk of HIV infection.
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OBJECTIVE: Patients infected with HIV-1 are at high risk of developing Epstein-Barr virus (EBV)-associated lymphoproliferative disorders. This study evaluated the impact of highly active antiretroviral therapy (HAART) on EBV infection. METHODS: To measure EBV content in peripheral blood lymphocytes (PBL) and in plasma, we set up a quantitative analysis using the real-time PCR. EBV latent membrane protein 1 (LMP1) expression was determined by reverse transcriptase-PCR. RESULTS: EBV levels were determined in 33 HIV-1- and EBV-coinfected patients at the start of HAART, and during therapy. At baseline, EBV content in PBL samples ranged from 8 to 14 532 copies/microg DNA. EBV levels transiently increased in nine out of 17 patients in whom HIV-1 plasmaviraemia declined to undetectable levels (virological response) and CD4 cell counts increased (immunological response), while they remained fairly stable or decreased in the other eight virological and immunological responders, and in seven patients who showed a virological response only. Of interest, a significant increase in EBV load was observed in five out of nine patients who showed an increase in CD4 cell counts but lack of HIV-1 suppression during HAART. This EBV increase was accompanied by the detection of both LMP1 transcripts in PBL and EBV DNA in plasma, and was paralleled by an increase in immunoglobulin levels, a marker of B-cell stimulation. CONCLUSIONS: These findings suggest that peripheral immune reconstitution during HAART without a reduction in HIV-1 replication may increase B-cell stimulation and the number of EBV-infected B cells.
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Terapia Antirretroviral Altamente Activa , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Herpesvirus Humano 4/fisiología , Carga Viral , Adulto , Anciano , Anticuerpos Antivirales/sangre , Recuento de Linfocito CD4 , ADN Viral/sangre , Infecciones por Virus de Epstein-Barr/tratamiento farmacológico , Infecciones por Virus de Epstein-Barr/virología , Femenino , Infecciones por VIH/inmunología , VIH-1/aislamiento & purificación , VIH-1/fisiología , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Leucocitos Mononucleares/virología , Masculino , Persona de Mediana Edad , Proteínas de la Matriz Viral/genética , Proteínas de la Matriz Viral/metabolismoRESUMEN
The entry of the human immunodeficiency virus type 1 (HIV-1) into target cells requires the interaction of viral envelope glycoprotein, gp120, with the human CD4 glycoprotein and a chemokine receptor, usually CCR5 or CXCR4. The natural ligand for CXCR4 is the chemokine SDF-1 that inhibits entry and replication of X4 HIV-1 strains. SDF-1 is produced in two forms, SDF-1alpha (68 residues) and SDF-1beta (72 residues); the difference between them lies in the additional four C-terminal amino acids in the SDF-1beta sequence. Despite the relevance of the N-terminal site in determining the SDF anti HIV-1 activity, SDF-1beta has a stronger activity than SDF-1alpha. Here we demonstrate that a synthetic peptide mapped on the C-terminus of SDF-1beta presents inhibitory activity, whereas an analogue reproducing the C-terminal trait of SDF-1alpha does not show any activity. The opposite biological effect of the two peptides correlates with the type of interaction they each have with heparin and chondroitin sulfate.
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Fármacos Anti-VIH/síntesis química , Quimiocinas CXC/química , Citocinas/química , Péptidos/síntesis química , Secuencia de Aminoácidos , Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacología , Línea Celular Tumoral , Quimiocina CXCL12 , Sulfatos de Condroitina/química , Dicroismo Circular , VIH/efectos de los fármacos , Heparina/química , Humanos , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Péptidos/química , Péptidos/farmacología , Relación Estructura-ActividadRESUMEN
Epstein-Barr virus (EBV) is a ubiquitous human γ-herpes virus which establishes a life-long asymptomatic infection in immunocompetent hosts. In human immunodeficiency virus type 1 (HIV-1) infected patients, the impaired immunosurveillance against EBV may favor the development of EBV-related diseases, ranging from lymphoproliferative disorders to B cell non-Hodgkin's lymphomas (NHL). Antiretroviral therapy (ART) has significantly modified the natural course of HIV-1 infection, resulting in decreased HIV-1 plasmaviremia, increased CD4 lymphocytes, and decreased opportunistic infections, indicating a restoration of immune functions. However, the impact of ART appears to be less favorable on EBV-related malignancies than on other AIDS-defining tumors, such as Kaposi's sarcoma, and NHL remains the most common cancer during the ART era. EBV-driven tumors are associated with selective expression of latent oncogenic proteins, but uncontrolled lytic cycle with virus replication and/or reactivation may favor cell transformation, at least in the early phases. Several host's factors may promote EBV reactivation and replication; besides immunodepression, inflammation/chronic immune stimulation may play an important role. Microbial pathogen-associated molecular patterns and endogenous damage-associated molecular patterns, through Toll-like receptors, activate the immune system and may promote EBV reactivation and/or polyclonal expansion of EBV-infected cells. A body of evidence suggests that chronic immune stimulation is a hallmark of HIV-1 pathogenesis and may persist even in ART-treated patients. This review focuses on lymphomagenesis driven by EBV both in the context of the natural history of HIV-1 infection and in ART-treated patients. Understanding the mechanisms involved in the expansion of EBV-infected cells is a premise for the identification of prognostic markers of EBV-associated malignancies.
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Molecular methods are important tools for diagnosis and monitoring of many lymphoproliferative disorders. The reliability of lymphoma diagnoses is strikingly different between developed and developing countries, partly due to lack of access to these advanced molecular analyses. To overcome these problems, we propose a new application of dried blood spots (DBS) for detecting clonal B-cell populations in peripheral blood (PB). We ensured that the DBS contained sufficient lymphocytes to perform a PCR-based clonality assay without producing false positives. Using the Namalwa B-cell line, we established that the assay is sensitive enough to detect 200 clonal cells in the analyzed sample. Very similar clonal results were obtained between DNA from DBS and fresh whole blood from patients with B-cell chronic lymphocytic leukemia. B-cell clonality can also be detected in DBS from African children with EBV-associated diseases. This is the first study demonstrating that clonality testing can be performed on DBS samples, thus improving the diagnostic and monitoring options for lymphoproliferative diseases in resource-limited settings.
Asunto(s)
Recolección de Muestras de Sangre/métodos , Reordenamiento Génico de Linfocito B , Genes de Inmunoglobulinas , Linfocitos B/metabolismo , Linfocitos B/patología , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/genética , Linfoma no Hodgkin/diagnóstico , Linfoma no Hodgkin/genética , Reacción en Cadena de la Polimerasa/métodosRESUMEN
OBJECTIVES: To evaluate the immunological and viral consequences of planned treatment interruptions (PTI) in children with HIV. DESIGN: This was an immunological and virological sub-study of the Paediatric European Network for Treatment of AIDS (PENTA) 11 trial, which compared CD4-guided PTI of antiretroviral therapy (ART) with continuous therapy (CT) in children. METHODS: HIV-1 RNA and lymphocyte subsets, including CD4 and CD8 cells, were quantified on fresh samples collected during the study; CD45RA, CD45RO and CD31 subpopulations were evaluated in some centres. For 36 (18 PTI, 18 CT) children, immunophenotyping was performed and cell-associated HIV-1 DNA analysed on stored samples to 48 weeks. RESULTS: In the PTI group, CD4 cell count fell rapidly in the first 12 weeks off ART, with decreases in both naïve and memory cells. However, the proportion of CD4 cells expressing CD45RA and CD45RO remained constant in both groups. The increase in CD8 cells in the first 12 weeks off ART in the PTI group was predominantly due to increases in RO-expressing cells. PTI was associated with a rapid and sustained increase in CD4 cells expressing Ki67 and HLA-DR, and increased levels of HIV-1 DNA. CONCLUSIONS: PTI in children is associated with rapid changes in CD4 and CD8 cells, likely due to increased cell turnover and immune activation. However, children off treatment may be able to maintain stable levels of naïve CD4 cells, at least in proportion to the memory cell pool, which may in part explain the observed excellent CD4 cell recovery with re-introduction of ART.
Asunto(s)
Antirretrovirales/uso terapéutico , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Adolescente , Antirretrovirales/administración & dosificación , Niño , Preescolar , Esquema de Medicación , Infecciones por VIH/virología , Humanos , Inmunofenotipificación , Recuento de Linfocitos , Factores de Tiempo , Resultado del Tratamiento , Carga ViralRESUMEN
BACKGROUND: The challenge of immune senescence has never been addressed in elderly cancer patients. This study compares the thymic output and peripheral blood telomere length in ≥70year old cancer patients. PATIENTS AND METHODS: Fifty-two elderly cancer patients and 39 age-matched controls without personal history of cancer were enrolled. All patients underwent a Comprehensive Geriatric Assessment (CGA), from which a multidimensional prognostic index (MPI) score was calculated. Peripheral blood samples were studied for naïve and recent thymic emigrant (RTE) CD4(+) and CD8(+) cells by flow cytometry. T-cell receptor rearrangement excision circle (TREC) levels, telomere length and telomerase activity in peripheral blood cells were quantified by real-time PCR. RESULTS: The percentages of CD8(+) naïve and CD8(+) RTE cells and TREC levels were significantly lower in cancer patients than in controls (p=0.003, p=0.004, p=0.031, respectively). Telomere lengths in peripheral blood cells were significantly shorter in cancer patients than in controls (p=0.046) and did not correlate with age in patients, whereas it did in controls (r=-0.354, p=0.031). Short telomere (≤median)/low TREC (≤median) profile was associated with higher risk of cancer (OR=3.68 [95% CI 1.22-11.11]; p=0.021). Neither unfitness on CGA nor MPI score were significantly related to thymic output or telomere length in either group. CONCLUSIONS: Immune senescence is significantly worse in elderly cancer patients than in age-matched controls. The low thymic output and the shorter telomeres in peripheral blood cells of cancer patients may reflect a pre-existing condition which facilitates the onset of malignancies in elderly people.
Asunto(s)
Envejecimiento/inmunología , Neoplasias de la Mama/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Neoplasias Colorrectales/inmunología , Timo/inmunología , Factores de Edad , Anciano , Anciano de 80 o más Años , Envejecimiento/sangre , Envejecimiento/genética , Biomarcadores/sangre , Neoplasias de la Mama/sangre , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/metabolismo , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Femenino , Citometría de Flujo , Reordenamiento Génico de Linfocito T , Evaluación Geriátrica , Humanos , Modelos Logísticos , Masculino , Oportunidad Relativa , Reacción en Cadena de la Polimerasa , Estudios Prospectivos , Factores de Riesgo , Telomerasa/metabolismo , Acortamiento del Telómero , Timo/metabolismoRESUMEN
Stromal cell-Derived Factor 1 (SDF1) is the natural ligand of CXCR4, the coreceptor of HIV-1 X4 viruses. This study investigated the role of the single nucleotide polymorphism (SNP) rs1801157 (NM_000609.5:c.*519G>A) of the SDF1 gene in the natural history of mother-to-child transmission of HIV-1 and disease progression of HIV-1-infected children. The study was conducted in 428 children born to HIV-1-seropositive mothers, who had not undergone antiretroviral therapy (ART) during pregnancy, and in 120 HIV-1-infected children for whom the end-point was the onset of AIDS or the initiation of ART; 16 children developed early AIDS (<24 months of life), 13 from 24 to 84 months of age, and 14 had late AIDS (>84 months). The rs1801157 SNP was not associated with risk of perinatal infection in any genetic models tested. By contrast, this SNP influenced disease progression in a time-dependent manner. rs1801157 GA heterozygous children had a higher risk of late AIDS (HR = 6.3, 95%CI 1.9-20.7, p = 0.002) than children with the rs1801157 GG genotype. Children were studied for viral coreceptor usage at birth, after 84 months of age and/or at AIDS onset. While R5 viruses using CCR5 coreceptor were predominant at birth (94%) and at early AIDS (85%), viruses using CXCR4 coreceptor emerged during the course of infection and were detected in 49% of children older than 84 months and in 62% of late AIDS. The rs1801157 SNP did not influence the emergence of R5X4 viruses, but children with the rs1801157 GA genotype and R5X4 viruses were at significantly higher risk of late AIDS than children with rs1801157 GG genotype (OR = 8.0, 95% CI 1.2-52.2, p = 0.029). Our results indicate that the rs1801157 SNP does not influence perinatal infection, but impacts disease progression. This effect is time-dependent and linked to the coreceptor-usage of viral variants that undergo evolution during the course of HIV-1 infection.