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1.
Haemophilia ; 27(3): e331-e339, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33772963

RESUMEN

INTRODUCTION: In patients with haemophilia A undergoing surgery, factor VIII (FVIII) replacement therapy by continuous infusion (CI) may offer an alternative to bolus infusion (BI). AIM: To compare the perioperative haemostatic efficacy and safety of antihaemophilic factor (recombinant) (ADVATE® ; Baxalta US Inc., a Takeda company, Lexington, MA, USA) CI or BI administration. METHODS: In this multicentre, phase III/IV, controlled study (NCT00357656), 60 previously treated adult patients with severe or moderately severe disease undergoing elective unilateral major orthopaedic surgery (knee replacement, n = 48; hip surgery, n = 4; other, n = 8) requiring drain placement were randomized to receive antihaemophilic factor (recombinant) CI (n = 29) or BI (n = 31) through postoperative day 7. Primary outcome measure was cumulative packed red blood cell (PRBC)/blood volume in the drainage fluid within 24 h after surgery, used to establish non-inferiority of CI to BI. RESULTS: CI:BI ratio of cumulative PRBC volume in the 24-h drainage fluid was 0.92 (p-value <.001 for non-inferiority; 95% confidence interval, 0.82-1.05). Total antihaemophilic factor (recombinant) dose per kg body weight received in the combined trans- and postoperative periods was similar with CI and BI to maintain targeted FVIII levels during/after surgery. Treatment-related adverse events (AEs) were reported in five patients treated by CI (eight events) and five treated by BI (six events), including two serious AEs in each arm. CONCLUSION: CI administration of antihaemophilic factor (recombinant) is a viable alternative to BI in patients with haemophilia A undergoing major orthopaedic surgery, providing comparable efficacy and safety.


Asunto(s)
Hemofilia A , Procedimientos Ortopédicos , Adulto , Pruebas de Coagulación Sanguínea , Factor VIII/uso terapéutico , Hemofilia A/tratamiento farmacológico , Hemofilia A/cirugía , Hemostasis , Humanos , Proteínas Recombinantes
2.
Thromb Haemost ; 120(5): 728-736, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32369844

RESUMEN

BACKGROUND: Factor VIII (FVIII) trough levels > 1 IU/dL in patients with severe hemophilia A receiving regular prophylaxis may optimize bleed protection. OBJECTIVES: In this post hoc analysis of patients receiving tertiary prophylaxis for approximately 1 year, the relationship between estimated FVIII levels and reported bleeds was investigated to predict the potential for zero bleeds. METHODS: Sixty-three patients (median [range] age, 28 [7-59] years) with severe hemophilia A (229 bleeds) were included. FVIII levels at time of each bleed were estimated from single-dose individual pharmacokinetics. The highest estimated FVIII level at which patients experienced a bleed was considered the "potentially effective trough level" for that bleed type. Kaplan-Meier estimates of proportions of patients with no bleeds above certain estimated FVIII levels were determined. Those not experiencing a bleed in the trial were assumed to have a bleed at 0 IU/dL (pragmatic approach) or at their median trough level (conservative approach). RESULTS: Kaplan-Meier estimates based on pragmatic approach predicted zero all bleeds, joint bleeds, and spontaneous joint bleeds in 1 year in 40, 43, and 63% of patients, respectively, when the potentially effective trough FVIII level was set at 1 IU/dL. Between 1 and 10 IU/dL, every 1 IU/dL rise in estimated FVIII level was associated with an additional 2% of patients having zero all bleeds. CONCLUSION: This post hoc analysis confirms benefits with trough levels of approximately 1 to 3 IU/dL in most patients starting tertiary prophylaxis; prophylaxis with higher trough levels may help patients to achieve zero bleeds.


Asunto(s)
Factor VIII/farmacocinética , Hemartrosis/prevención & control , Hemofilia A/tratamiento farmacológico , Hemostasis/efectos de los fármacos , Hemostáticos/farmacocinética , Modelos Biológicos , Prevención Terciaria , Adolescente , Adulto , Canadá , Niño , Europa (Continente) , Factor VIII/administración & dosificación , Hemartrosis/sangre , Hemartrosis/diagnóstico , Hemofilia A/sangre , Hemofilia A/diagnóstico , Hemostáticos/administración & dosificación , Hemostáticos/sangre , Humanos , Persona de Mediana Edad , Factores de Riesgo , Índice de Severidad de la Enfermedad , Estados Unidos , Adulto Joven
3.
Haemophilia ; 26(3): 478-486, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32338433

RESUMEN

INTRODUCTION: Antihaemophilic factor (recombinant) (rAHF; ADVATE® ) is approved for prophylaxis and treatment of bleeding in children and adults with haemophilia A. Reconstitution in 2 mL sterile water for injection instead of 5 mL allows for a 60% reduction in infusion volume and administration time, but could increase the likelihood of hypersensitivity and infusion-related reactions, especially in children. AIM: To assess local tolerability, safety and effectiveness of rAHF 2 mL during routine clinical practice factor VIII (FVIII) replacement (on-demand and prophylaxis) in children with severe (FVIII < 1%) or moderately severe (FVIII 1%-2%) haemophilia A. METHODS: This was a prospective, non-interventional, postauthorization safety surveillance study (NCT02093741). Eligible patients were previously treated with rAHF and had a negative inhibitor test result during ≤10 exposure days prior to study entry. RESULTS: Of 65 patients enrolled (0-11 years of age), 54 and 11 had severe and moderately severe haemophilia A, respectively; 56 patients received prophylaxis, and 11 had ≤50 exposure days, of which 4 had ≤4 exposure days. No patients reported local hypersensitivity reactions, treatment-related adverse events or developed inhibitors. Investigators rated overall effectiveness of rAHF 2 mL prophylaxis as excellent or good. Ninety-four bleeding events in 34 patients were treated. Haemostatic effectiveness was rated as excellent or good for 75.8% of bleeds; 86.2% of bleeds required 1 or 2 infusions. CONCLUSION: In children with severe/moderately severe haemophilia A, no hypersensitivity reactions were reported with rAHF 2 mL treatment, and the safety and effectiveness are consistent with data previously reported for rAHF 5 mL.


Asunto(s)
Factor VIII/uso terapéutico , Hemofilia A/tratamiento farmacológico , Agua/química , Niño , Preescolar , Monitoreo Epidemiológico , Factor VIII/farmacología , Femenino , Humanos , Lactante , Recién Nacido , Inyecciones , Masculino
5.
Biologics ; 8: 115-27, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24741292

RESUMEN

Detailed analysis of data from studies of recombinant antihemophilic factor produced using a plasma/albumin-free method (rAHF-PFM) in previously treated patients showed a substantial level of interpatient variation in pharmacokinetics (PKs), factor VIII dosing, and annualized bleed rate (ABR), suggesting that individual patient characteristics contributed to outcome. For example, plasma half-life (t1/2), recovery, and clearance appeared to differ between patients aged <6 years and 10-65 years. Prophylaxis resulted in lower ABRs than episodic treatment in both age groups; better adherence to the prophylactic regimen resulted in a lower ABR in patients aged 10-65 years. The weekly frequency of dosing and adherence to dosing were both significantly and inversely related to the rate of bleeding (young children, P<0.0001 for both all bleeds and joint bleeds; older patients, P<0.0001 for all bleeds and P<0.05 for joint bleeds), as was adherence to dosing frequency (P<0.0001 for all comparisons). A post-marketing randomized study of prophylaxis demonstrated that a PK-guided dosing regimen, based on an individual patient's rAHF-PFM PK (infusion interval, estimated t1/2, and recovery), was as effective as standard prophylaxis and that both prophylactic regimens were superior to episodic treatment with respect to ABR and quality of life measures. Thus, compared with standard prophylaxis, the PK-guided regimen achieved comparable efficacy with fewer weekly infusions. A two-compartment population PK model describes the PK data across the entire age range and forms the basis for future PK-guided therapy with rAHF-PFM. The model confirmed a shorter t1/2 and faster clearance of rAHF-PFM in children <6 years of age versus patients ≥10 years and predicted similar PK parameters with either a full or reduced blood sampling schedule, offering the potential for the use of PK-guided, individualized treatment in the routine clinical care setting.

6.
J Virol ; 87(11): 6073-80, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23536679

RESUMEN

APOBEC3 proteins mediate potent antiretroviral activity by hypermutating the retroviral genome during reverse transcription. To counteract APOBEC3 and gain a replicative advantage, lentiviruses such as human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency virus (SIV) have evolved the Vif protein, which targets APOBEC3 proteins for proteasomal degradation. However, the proteasome plays a critical role in the generation of T cell peptide epitopes. Whether Vif-mediated destruction of APOBEC3 proteins leads to the generation and presentation of APOBEC3-derived T cell epitopes on the surfaces of lentivirus-infected cells remains unknown. Here, using peptides derived from multiple Vif-sensitive APOBEC3 proteins, we identified APOBEC3-specific T cell responses in both HIV-1-infected patients and SIV-infected rhesus macaques. These results raise the possibility that these T cell responses may be part of the larger antiretroviral immune response.


Asunto(s)
Linfocitos T CD8-positivos/virología , Citidina Desaminasa/inmunología , Citosina Desaminasa/inmunología , Infecciones por VIH/enzimología , VIH-1/fisiología , Síndrome de Inmunodeficiencia Adquirida del Simio/enzimología , Virus de la Inmunodeficiencia de los Simios/fisiología , Desaminasa APOBEC-3G , Adulto , Animales , Linfocitos T CD8-positivos/inmunología , Citidina Desaminasa/genética , Citosina Desaminasa/genética , Femenino , Productos del Gen vif/genética , Productos del Gen vif/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/genética , VIH-1/inmunología , Humanos , Macaca mulatta , Masculino , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/genética , Virus de la Inmunodeficiencia de los Simios/inmunología
7.
Ann Hematol ; 92(5): 689-98, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23324986

RESUMEN

Antihemophilic factor (recombinant), plasma/albumin-free method (rAHF-PFM) was evaluated during routine practice in Germany, among consenting subjects of any age with hemophilia A (HA) and no prior exposure to rAHF-PFM. The treating physician chose the dosing and inhibitor testing frequency. Data were captured for 12 months/subject from diaries and clinic records. Of 152 subjects, 69 % had severe HA, and 89 % had >150 exposure 6 days (ED) at baseline. The majority of subjects (63 %) were treated by continuous prophylaxis (CP). Assignment to CP was more likely for subjects ≥2 years of age and for those with FVIII ≤ 2 %. Median FVIII consumption was 3,548 IU/kg/year for CP and 999 IU/kg/year for continuous on-demand (OD) therapy. Median annual bleed rate was 0.82 for CP and 4.06 for OD. Of 1,218 bleeds, 97 % were home-treated and 68 % of evaluable bleeds involved joints. Based on evaluable subjects' worst ratings, 83/91 (91 %) on CP had a rating of excellent/good for all prophylactic assessments, 55/59 (93 %) on CP and 41/42 (98 %) on OD had a rating of excellent/good for all bleeding assessments. The de novo high-titer FVIII inhibitor rate in subjects with >50 ED at baseline was 1/144 (0.69 %; 95 % CI, 0.02 % to 3.81 %). No high-titer inhibitor occurred in patients with severe HA and >50 ED at baseline. Reduced HRQOL physical scores were predicted by older age (p < 0.0001), HIV positivity (p = 0.02), and presence of ≥1 target joint (p = 0.003). ADVATE rAHF-PFM is safe and efficacious for routine CP or OD management of patients with HA.


Asunto(s)
Quimioprevención , Factor VIII/administración & dosificación , Hemofilia A/tratamiento farmacológico , Vigilancia de Productos Comercializados , Calidad de Vida , Adolescente , Adulto , Quimioprevención/métodos , Niño , Preescolar , Aprobación de Drogas , Alemania , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , Proteínas Recombinantes/administración & dosificación , Albúmina Sérica/administración & dosificación , Adulto Joven
8.
PLoS One ; 7(6): e39311, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22768072

RESUMEN

BACKGROUND: Translational errors can result in bypassing of the main viral protein reading frames and the production of alternate reading frame (ARF) or cryptic peptides. Within HIV, there are many such ARFs in both sense and the antisense directions of transcription. These ARFs have the potential to generate immunogenic peptides called cryptic epitopes (CE). Both antiretroviral drug therapy and the immune system exert a mutational pressure on HIV-1. Immune pressure exerted by ARF CD8(+) T cells on the virus has already been observed in vitro. HAART has also been described to select HIV-1 variants for drug escape mutations. Since the mutational pressure exerted on one location of the HIV-1 genome can potentially affect the 3 reading frames, we hypothesized that ARF responses would be affected by this drug pressure in vivo. METHODOLOGY/PRINCIPAL FINDINGS: In this study we identified new ARFs derived from sense and antisense transcription of HIV-1. Many of these ARFs are detectable in circulating viral proteins. They are predominantly found in the HIV-1 env nucleotide region. We measured T cell responses to 199 HIV-1 CE encoded within 13 sense and 34 antisense HIV-1 ARFs. We were able to observe that these ARF responses are more frequent and of greater magnitude in chronically infected individuals compared to acutely infected patients, and in patients on HAART, the breadth of ARF responses increased. CONCLUSIONS/SIGNIFICANCE: These results have implications for vaccine design and unveil the existence of potential new epitopes that could be included as vaccine targets.


Asunto(s)
Terapia Antirretroviral Altamente Activa , Progresión de la Enfermedad , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , VIH-1/genética , VIH-1/inmunología , Sistemas de Lectura/inmunología , Enfermedad Aguda , Adulto , Secuencia de Aminoácidos , Secuencia de Bases , Enfermedad Crónica , Genoma Viral/genética , Geografía , Infecciones por VIH/genética , Humanos , Datos de Secuencia Molecular , Nucleótidos/genética , Péptidos/química , Péptidos/inmunología , Sistemas de Lectura/genética , Recombinación Genética/genética , Eliminación de Secuencia , Linfocitos T/inmunología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/química , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética
9.
Blood ; 119(2): 612-8, 2012 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-22042695

RESUMEN

Comparison of the pharmacokinetics (PK) of a coagulation factor between groups of patients can be biased by differences in study protocols, in particular between blood sampling schedules. This could affect clinical dose tailoring, especially in children. The aim of this study was to describe the relationships of the PK of factor VIII (FVIII) with age and body weight by a population PK model. The potential to reduce blood sampling was also explored. A model was built for FVIII PK from 236 infusions of recombinant FVIII in 152 patients (1-65 years of age) with severe hemophilia A. The PK of FVIII over the entire age range was well described by a 2-compartment model and a previously reported problem, resulting from differences in blood sampling, to compare findings from children and adults was practically abolished. The decline in FVIII clearance and increase in half-life with age could be described as continuous functions. Retrospective reduction of blood sampling from 11 to 5 samples made no important difference to the estimates of PK parameters. The obtained findings can be used as a basis for PK-based dose tailoring of FVIII in clinical practice, in all age groups, with minimal blood sampling.


Asunto(s)
Factor VIII/administración & dosificación , Factor VIII/farmacocinética , Hemofilia A/prevención & control , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacocinética , Adolescente , Adulto , Factores de Edad , Anciano , Peso Corporal , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Femenino , Hemofilia A/sangre , Hemofilia A/epidemiología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Modelos Teóricos , Pronóstico , Estudios Retrospectivos , Distribución Tisular , Estados Unidos/epidemiología , Adulto Joven
10.
J Virol ; 85(14): 6977-85, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21525339

RESUMEN

Eight percent of the human genome is composed of human endogenous retroviruses (HERVs), which are thought to be inactive remnants of ancient infections. Previously, we showed that individuals with early HIV-1 infection have stronger anti-HERV T cell responses than uninfected controls. In this study, we investigated whether these responses persist in chronic HIV-1 infection and whether they have a role in the control of HIV-1. Peripheral blood mononuclear cells (PBMCs) from 88 subjects diagnosed with HIV-1 infection for at least 1 year (median duration of diagnosis, 13 years) were tested for responses against HERV peptides in gamma interferon (IFN-γ) enzyme immunospot (ELISPOT) assays. Individuals who control HIV-1 viremia without highly active antiretroviral therapy (HAART) had stronger and broader HERV-specific T cell responses than HAART-suppressed patients, virologic noncontrollers, immunologic progressors, and uninfected controls (P < 0.05 for each pairwise comparison). In addition, the magnitude of the anti-HERV T cell response was inversely correlated with HIV-1 viral load (r(2) = 0.197, P = 0.0002) and associated with higher CD4(+) T cell counts (r(2) = 0.072, P = 0.027) in untreated patients. Flow cytometric analyses of an HLA-B51-restricted CD8(+) HERV response in one HIV-1-infected individual revealed a less activated and more differentiated phenotype than that stimulated by a homologous HIV-1 peptide. HLA-B51 tetramer dual staining within this individual confirmed two different T cell populations corresponding to these HERV and HIV-1 epitopes, ruling out cross-reactivity. These findings suggest a possible role for anti-HERV immunity in the control of chronic HIV-1 infection and provide support for a larger effort to design an HIV-1 vaccine that targets conserved antigens such as HERV.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Retrovirus Endógenos/inmunología , Infecciones por VIH/inmunología , VIH-1/fisiología , Terapia Antirretroviral Altamente Activa , Enfermedad Crónica , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Productos del Gen env/inmunología , Productos del Gen gag/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Humanos , Inmunofenotipificación , Masculino
11.
PLoS One ; 5(4): e10249, 2010 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-20422053

RESUMEN

BACKGROUND: The HLA-B*35-Px allele has been associated with rapid disease progression in HIV-1 infection, in contrast to the HLA-B*35-Py allele. METHODOLOGY/PRINCIPAL FINDINGS: Immune responses to two HLA-B*35 restricted HIV-1 specific CTL epitopes and their variants were followed longitudinally during early HIV-1 infection in 16 HLA-B*35+ individuals. Subjects expressing HLA-B*35-Px alleles showed no difference in response to the consensus epitopes compared to individuals with HLA-B*35-Py alleles. Surprisingly, all the HLA-B*35-Px+ individuals responded to epitope-variants even in the absence of a consensus response. Sequencing of the viral population revealed no evidence of variant virus in any of the individuals. CONCLUSIONS/SIGNIFICANCE: This demonstrates a novel phenomenon that distinguishes individuals with the HLA-B*35-Px rapid progressing allele and those with the HLA-B*35-Py slower progressing allele.


Asunto(s)
Alelos , Linfocitos T CD8-positivos/inmunología , Epítopos de Linfocito T/inmunología , VIH-1/inmunología , Antígeno HLA-B35/genética , Linfocitos T Citotóxicos/inmunología , Recuento de Linfocito CD4 , Progresión de la Enfermedad , Epítopos de Linfocito T/genética , Variación Genética , Infecciones por VIH/sangre , Infecciones por VIH/diagnóstico , Infecciones por VIH/inmunología , Humanos , Estudios Longitudinales , Especificidad del Receptor de Antígeno de Linfocitos T , Carga Viral
12.
J Acquir Immune Defic Syndr ; 53(1): 36-46, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19910798

RESUMEN

We analyzed immune responses in chronically HIV-infected individuals who took part in a treatment interruption (TI) trial designed for patients who initiated antiretroviral therapy within 6 months of seroconversion. In the 2 subjects who exhibited the best viral control, we detected CD8(+) T-cell responses against 1-2 Gag epitopes during the early weeks of TI and a subsequent increase in the number of epitopes recognized by the later time points. Each of these subjects developed mutations within the epitopes targeted by the highest magnitude responses. In the subject with the worst viral control, we detected responses against 2 Gag epitopes throughout the entire TI and no Gag mutations. The magnitude of these responses increased dramatically with time, greatly exceeding those detected in the virologic controllers. The highest levels of contemporaneous autologous neutralizing antibody activity were detected in the virologic controllers, and a subsequent escape mutation developed within the envelope gene of one controller that abrogated the response. These data suggest that immune escape mutations are a sign of viral control during TI, and that the absence of immune escape mutations in the presence of high levels of viral replication indicates the lack of an effective host immune response.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Epítopos/inmunología , Infecciones por VIH/inmunología , VIH-1/genética , VIH-1/inmunología , Privación de Tratamiento , Anticuerpos Neutralizantes/sangre , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/virología , Epítopos/genética , Proteínas gp160 de Envoltorio del VIH/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Humanos , Interferón gamma/biosíntesis , Interferón gamma/inmunología , Estudios Longitudinales , Mutación , Pruebas de Neutralización , Carga Viral , Replicación Viral/genética , Replicación Viral/inmunología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología
13.
J Exp Med ; 205(12): 2763-79, 2008 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-19001139

RESUMEN

Progressive loss of T cell functionality is a hallmark of chronic infection with human immunodeficiency virus 1 (HIV-1). We have identified a novel population of dysfunctional T cells marked by surface expression of the glycoprotein Tim-3. The frequency of this population was increased in HIV-1-infected individuals to a mean of 49.4 +/- SD 12.9% of CD8(+) T cells expressing Tim-3 in HIV-1-infected chronic progressors versus 28.5 +/- 6.8% in HIV-1-uninfected individuals. Levels of Tim-3 expression on T cells from HIV-1-infected inviduals correlated positively with HIV-1 viral load and CD38 expression and inversely with CD4(+) T cell count. In progressive HIV-1 infection, Tim-3 expression was up-regulated on HIV-1-specific CD8(+) T cells. Tim-3-expressing T cells failed to produce cytokine or proliferate in response to antigen and exhibited impaired Stat5, Erk1/2, and p38 signaling. Blocking the Tim-3 signaling pathway restored proliferation and enhanced cytokine production in HIV-1-specific T cells. Thus, Tim-3 represents a novel target for the therapeutic reversal of HIV-1-associated T cell dysfunction.


Asunto(s)
Infecciones por VIH/inmunología , VIH-1/inmunología , Proteínas de la Membrana/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos T/inmunología , Animales , Antígenos CD/genética , Antígenos CD/inmunología , Terapia Antirretroviral Altamente Activa , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/inmunología , Progresión de la Enfermedad , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/inmunología , Factor de Transcripción GATA3/genética , Factor de Transcripción GATA3/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/patología , Infecciones por VIH/fisiopatología , VIH-1/patogenicidad , Antígenos HLA , Receptor 2 Celular del Virus de la Hepatitis A , Humanos , Proteínas de la Membrana/genética , Fenotipo , Receptor de Muerte Celular Programada 1 , Factor de Transcripción STAT5/genética , Factor de Transcripción STAT5/inmunología , Transducción de Señal/inmunología , Proteínas de Dominio T Box/genética , Proteínas de Dominio T Box/inmunología , Subgrupos de Linfocitos T/citología , Linfocitos T/citología , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/inmunología
14.
J Infect Dis ; 197(1): 117-25, 2008 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18171294

RESUMEN

Natural killer (NK) cells are believed to play a role in human immunodeficiency virus type 1 (HIV-1) disease progression, and NK cell levels are reduced in individuals with chronic HIV-1 infection. Interleukin (IL)-2 therapy results in an expansion of CD4(+) T cells as well as NK cells; however, little is known about the detailed effects of IL-2 therapy on NK cells in HIV-1 infection in general and in early infection in particular. Here, we investigated the effects of combined IL-2 therapy and antiretroviral therapy (ART) on the number, frequency, phenotype, and interferon (IFN)-gamma production of NK cells in individuals with early HIV-1 infection. Patients randomized to receive combined ART and IL-2 therapy predominantly expanded CD56(dim) NK cells, and the expansion was greater than in patients randomized to receive ART alone. Importantly, NK cell receptor expression and IFN-gamma production were maintained over time. This reconstitution of NK cells may be useful in helping contain viremia if patients discontinue therapy or develop drug resistance.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Antígeno CD56/inmunología , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Interleucina-2/farmacología , Células Asesinas Naturales/efectos de los fármacos , Adulto , Antirretrovirales/uso terapéutico , Quimioterapia Combinada , Femenino , Infecciones por VIH/inmunología , VIH-1/inmunología , Humanos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/virología , Masculino , Estudios Prospectivos
15.
J Leukoc Biol ; 83(2): 254-62, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17982112

RESUMEN

During the course of HIV-1 infection, the status of immune activation has been determined to be a powerful indicator of disease progression. The immune system has adopted self-regulatory mechanisms to counterbalance undesirable immune responses. CD25+CD4+ T regulatory (Treg) cells that express the transcription regulator, forkhead box P3 (FOXP3), play an important role in this immunosuppression. Using a combination of Treg cell discriminatory markers (FOXP3, CD25, CD127), we predicted that an expansion of Treg cell subsets would negatively correlate with immune activation during the early stages of HIV-1 infection. We report that FOXP3+CD127lo expressing CD4+ T cells increases in primary HIV-1 infection over time. Furthermore, the FOXP3+CD127lo CD4+ T cells may, in fact, reduce the levels of T cell activation following primary infection. It is interesting that the positive correlation between FOXP3+CD127lo CD4+ and CD25+CD127lo CD4+ T cells noted in HIV-uninfected persons is not only lost but may also be reversed in early, chronic HIV-1 infection. Unlike FOXP3+CD127lo CD4+, the level of FOXP3+CD25+CD127lo CD4+ T cells did not correlate with T cell activation, suggesting that these cells were not effective in reducing T cell activation. These observations suggest that different Treg populations may have different effects on reducing immune activation in HIV-1 infection and that the FOXP3+CD127lo CD4+ T cell population may be particularly important in limiting immune activation.


Asunto(s)
ADP-Ribosil Ciclasa 1/análisis , Linfocitos T CD8-positivos/inmunología , Factores de Transcripción Forkhead/análisis , Infecciones por VIH/inmunología , VIH-1 , Subunidad alfa del Receptor de Interleucina-7/análisis , Glicoproteínas de Membrana/análisis , Subgrupos de Linfocitos T/inmunología , Linfocitos T Reguladores/inmunología , Recuento de Linfocito CD4 , División Celular , Progresión de la Enfermedad , Humanos , Inmunofenotipificación , Subunidad alfa del Receptor de Interleucina-2/análisis , Activación de Linfocitos
16.
PLoS Pathog ; 3(11): e165, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17997601

RESUMEN

Human endogenous retroviruses (HERVs) are remnants of ancient infectious agents that have integrated into the human genome. Under normal circumstances, HERVs are functionally defective or controlled by host factors. In HIV-1-infected individuals, intracellular defense mechanisms are compromised. We hypothesized that HIV-1 infection would remove or alter controls on HERV activity. Expression of HERV could potentially stimulate a T cell response to HERV antigens, and in regions of HIV-1/HERV similarity, these T cells could be cross-reactive. We determined that the levels of HERV production in HIV-1-positive individuals exceed those of HIV-1-negative controls. To investigate the impact of HERV activity on specific immunity, we examined T cell responses to HERV peptides in 29 HIV-1-positive and 13 HIV-1-negative study participants. We report T cell responses to peptides derived from regions of HERV detected by ELISPOT analysis in the HIV-1-positive study participants. We show an inverse correlation between anti-HERV T cell responses and HIV-1 plasma viral load. In HIV-1-positive individuals, we demonstrate that HERV-specific T cells are capable of killing cells presenting their cognate peptide. These data indicate that HIV-1 infection leads to HERV expression and stimulation of a HERV-specific CD8+ T cell response. HERV-specific CD8+ T cells have characteristics consistent with an important role in the response to HIV-1 infection: a phenotype similar to that of T cells responding to an effectively controlled virus (cytomegalovirus), an inverse correlation with HIV-1 plasma viral load, and the ability to lyse cells presenting their target peptide. These characteristics suggest that elicitation of anti-HERV-specific immune responses is a novel approach to immunotherapeutic vaccination. As endogenous retroviral sequences are fixed in the human genome, they provide a stable target, and HERV-specific T cells could recognize a cell infected by any HIV-1 viral variant. HERV-specific immunity is an important new avenue for investigation in HIV-1 pathogenesis and vaccine design.


Asunto(s)
Antígenos Virales/inmunología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Retrovirus Endógenos/inmunología , Infecciones por VIH/virología , Estudios de Cohortes , Estudios Transversales , Citometría de Flujo , Infecciones por VIH/inmunología , VIH-1 , Humanos , ARN Viral/sangre , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Carga Viral
17.
J Virol ; 81(11): 5759-65, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17376902

RESUMEN

CD8(+) T cells are believed to play an important role in the control of human immunodeficiency virus type 1 (HIV-1) infection. However, despite intensive efforts, it has not been possible to consistently link the overall magnitude of the CD8(+) T-cell response with control of HIV-1. Here, we have investigated the association of different CD8(+) memory T-cell subsets responding to HIV-1 in early infection with future control of HIV-1 viremia. Our results demonstrate that both a larger proportion and an absolute number of HIV-1-specific CD8(+) CCR7(-) CD45RA(+) effector memory T cells (T(EMRA) cells) were associated with a lower future viral load set point. In contrast, a larger absolute number of HIV-1-specific CD8(+) CCR7(-) CD45RA(-) effector memory T cells (T(EM)) was not related to the viral load set point. Overall, the findings suggest that CD8(+) T(EMRA) cells have superior antiviral activity and indicate that both qualitative and quantitative aspects of the CD8(+) T-cell response need to be considered when defining the characteristics of protective immunity to HIV-1.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Epítopos de Linfocito T/inmunología , Infecciones por VIH/virología , VIH-1/inmunología , Subgrupos de Linfocitos T/inmunología , Carga Viral , Viremia/inmunología , Viremia/virología , Adulto , Linfocitos T CD8-positivos/virología , Células Cultivadas , Femenino , Productos del Gen gag/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/patología , Humanos , Memoria Inmunológica , Inmunofenotipificación , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Subgrupos de Linfocitos T/patología , Subgrupos de Linfocitos T/virología , Viremia/patología
18.
PLoS One ; 2(2): e225, 2007 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-17311088

RESUMEN

BACKGROUND: Antigen-specific CTL responses are thought to play a central role in containment of HIV-1 infection, but no consistent correlation has been found between the magnitude and/or breadth of response and viral load changes during disease progression. METHODS AND FINDINGS: We undertook a detailed investigation of longitudinal CTL responses and HIV-1 evolution beginning with primary infection in 11 untreated HLA-A2 positive individuals. A subset of patients developed broad responses, which selected for consensus B epitope variants in Gag, Pol, and Nef, suggesting CTL-induced adaptation of HIV-1 at the population level. The patients who developed viral escape mutations and broad autologous CTL responses over time had a significantly higher increase in viral load during the first year of infection compared to those who did not develop viral escape mutations. CONCLUSIONS: A continuous dynamic development of CTL responses was associated with viral escape from temporarily effective immune responses. Our results suggest that broad CTL responses often represent footprints left by viral CTL escape rather than effective immune control, and help explain earlier findings that fail to show an association between breadth of CTL responses and viral load. Our results also demonstrate that CTL pressures help to maintain certain elements of consensus viral sequence, which likely represent viral escape from common HLA-restricted CTL responses. The ability of HIV to evolve to escape CTL responses restricted by a common HLA type highlights the challenges posed to development of an effective CTL-based vaccine.


Asunto(s)
Antígenos VIH/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , Evasión Inmune , Linfocitos T Citotóxicos/inmunología , Sustitución de Aminoácidos , Secuencia de Bases , Secuencia de Consenso , Progresión de la Enfermedad , Epítopos/genética , Epítopos/inmunología , Evolución Molecular , Femenino , Antígenos VIH/genética , VIH-1/genética , Antígeno HLA-A2/inmunología , Humanos , Evasión Inmune/genética , Interferón gamma/sangre , Masculino , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia , Homología de Secuencia de Ácido Nucleico , Factor de Necrosis Tumoral alfa/análisis , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen nef del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen nef del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/inmunología
19.
AIDS ; 21(2): 239-41, 2007 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-17197817

RESUMEN

We determined whether methamphetamine use is associated with the increased prevalence of primary HIV drug resistance among a cohort of men who have sex with men recently infected with HIV. In multivariate analysis, we found that frequent methamphetamine use was strongly associated with primary non-nucleoside reverse transcriptase inhibitor resistance, but not with protease inhibitor or nucleoside reverse transcriptase inhibitor resistance. We postulate that this association may be caused by methamphetamine-associated treatment interruptions among source partners.


Asunto(s)
Fármacos Anti-VIH/farmacología , Farmacorresistencia Viral , VIH-1/efectos de los fármacos , Metanfetamina , Trastornos Relacionados con Sustancias/complicaciones , Adulto , Estudios Transversales , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/transmisión , Infecciones por VIH/virología , Homosexualidad Masculina , Humanos , Masculino , Inhibidores de la Transcriptasa Inversa/farmacología
20.
AIDS Res Hum Retroviruses ; 22(8): 757-62, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16910831

RESUMEN

Perturbations of plasma IL-10, IL-12, IL-13, TNF-alpha, and IFN-gamma were measured longitudinally in HIV-1 seroconverting plasma donors and were compared to subjects with symptomatic primary HIV-1 infection. Control groups included uninfected patients with symptoms and risks for primary HIV-1, healthy controls, and asymptomatic plasma donors with primary HCV. IL-10, TNF-alpha, and IFN-gamma rapidly rose in acute HIV-1 infection, while IL-13 predominated in acute HCV. Subjects with symptomatic primary HIV-1 had higher cytokine levels than asymptomatic subjects, statistically significant for TNF-alpha. Cytokine alterations occurred within 7 days of detectable HIV-1 viremia, emphasizing the need to study the earliest events of infection.


Asunto(s)
Citocinas/sangre , Infecciones por VIH/inmunología , VIH-1/inmunología , Biomarcadores/sangre , Donantes de Sangre , Femenino , Infecciones por VIH/sangre , Hepacivirus/inmunología , Hepatitis C/sangre , Hepatitis C/inmunología , Humanos , Interferón-alfa/sangre , Masculino , Plasmaféresis , Factor de Necrosis Tumoral alfa/metabolismo , Carga Viral
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