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1.
Nat Med ; 30(4): 1013-1022, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38538867

RESUMEN

Therapeutic vaccines that elicit cytotoxic T cell responses targeting tumor-specific neoantigens hold promise for providing long-term clinical benefit to patients with cancer. Here we evaluated safety and tolerability of a therapeutic vaccine encoding 20 shared neoantigens derived from selected common oncogenic driver mutations as primary endpoints in an ongoing phase 1/2 study in patients with advanced/metastatic solid tumors. Secondary endpoints included immunogenicity, overall response rate, progression-free survival and overall survival. Eligible patients were selected if their tumors expressed one of the human leukocyte antigen-matched tumor mutations included in the vaccine, with the majority of patients (18/19) harboring a mutation in KRAS. The vaccine regimen, consisting of a chimp adenovirus (ChAd68) and self-amplifying mRNA (samRNA) in combination with the immune checkpoint inhibitors ipilimumab and nivolumab, was shown to be well tolerated, with observed treatment-related adverse events consistent with acute inflammation expected with viral vector-based vaccines and immune checkpoint blockade, the majority grade 1/2. Two patients experienced grade 3/4 serious treatment-related adverse events that were also dose-limiting toxicities. The overall response rate was 0%, and median progression-free survival and overall survival were 1.9 months and 7.9 months, respectively. T cell responses were biased toward human leukocyte antigen-matched TP53 neoantigens encoded in the vaccine relative to KRAS neoantigens expressed by the patients' tumors, indicating a previously unknown hierarchy of neoantigen immunodominance that may impact the therapeutic efficacy of multiepitope shared neoantigen vaccines. These data led to the development of an optimized vaccine exclusively targeting KRAS-derived neoantigens that is being evaluated in a subset of patients in phase 2 of the clinical study. ClinicalTrials.gov registration: NCT03953235 .


Asunto(s)
Vacunas contra el Cáncer , Neoplasias , Vacunas , Humanos , Antígenos de Neoplasias , Vacunas contra el Cáncer/efectos adversos , Antígenos HLA , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Proteínas Proto-Oncogénicas p21(ras)/genética , Vacunas/uso terapéutico
2.
Nat Commun ; 14(1): 3274, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-37280238

RESUMEN

SARS-CoV-2 has resulted in high levels of morbidity and mortality world-wide, and severe complications can occur in older populations. Humoral immunity induced by authorized vaccines wanes within 6 months, and frequent boosts may only offer transient protection. GRT-R910 is an investigational self-amplifying mRNA (samRNA)-based SARS-CoV-2 vaccine delivering full-length Spike and selected conserved non-Spike T cell epitopes. This study reports interim analyses for a phase I open-label dose-escalation trial evaluating GRT-R910 in previously vaccinated healthy older adults (NCT05148962). Primary endpoints of safety and tolerability were assessed. Most solicited local and systemic adverse events (AEs) following GRT-R910 dosing were mild to moderate and transient, and no treatment-related serious AEs were observed. The secondary endpoint of immunogenicity was assessed via IgG binding assays, neutralization assays, interferon-gamma ELISpot, and intracellular cytokine staining. Neutralizing antibody titers against ancestral Spike and variants of concern were boosted or induced by GRT-R910 and, contrasting to authorized vaccines, persisted through at least 6 months after the booster dose. GRT-R910 increased and/or broadened functional Spike-specific T cell responses and primed functional T cell responses to conserved non-Spike epitopes. This study is limited due to small sample size, and additional data from ongoing studies will be required to corroborate these interim findings.


Asunto(s)
COVID-19 , ARN Mensajero/genética , COVID-19/prevención & control , Humanos , Anciano , Masculino , Femenino , Persona de Mediana Edad , Anciano de 80 o más Años , Ensayos Clínicos como Asunto , Anticuerpos Antivirales/inmunología , Anticuerpos Neutralizantes/inmunología , Linfocitos T/inmunología
3.
Int J Nurs Pract ; 29(5): e13120, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36502807

RESUMEN

BACKGROUND: Performing cardiopulmonary resuscitation in non-critical care hospital wards is a stressful event for the registered nurse; stress may negatively affect performance. Delays in initiating basic life support and following current basic life support algorithms have been reported globally. AIM: The aim of this review was to investigate factors that can affect registered nurses' experiences of performing basic life support. METHODS: Using the five-step integrative literature review method from Whittemore and Knafl, this review searched articles published between January 2000 and June 2022 for qualitative and quantitative primary studies from the databases CINAHL Complete (EBSCO), Medline (Web of Science), Scopus and PubMed. RESULTS: Nine studies from eight countries met the inclusion criteria and were appraised here. Five themes relating to factors affecting the performance of basic life support were found during this review: staff interaction issues, confidence concerns, fear of harm and potential litigation, defibrillation concerns and basic life support training issues. CONCLUSIONS: This review revealed several concerns experienced by registered nurses in performing basic life support and highlights a lack of research. Factors affecting nurses' experiences need to be understood. This will allow education to focus on consideration of human factors, or non-technical skills during basic life support training, as well as technical skills, to improve outcomes for patients experiencing an in-hospital cardiopulmonary arrest.


Asunto(s)
Competencia Clínica , Enfermeras y Enfermeros , Humanos , Hospitales , Escolaridad
4.
Nat Med ; 28(8): 1619-1629, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35970920

RESUMEN

Checkpoint inhibitor (CPI) therapies provide limited benefit to patients with tumors of low immune reactivity. T cell-inducing vaccines hold promise to exert long-lasting disease control in combination with CPI therapy. Safety, tolerability and recommended phase 2 dose (RP2D) of an individualized, heterologous chimpanzee adenovirus (ChAd68) and self-amplifying mRNA (samRNA)-based neoantigen vaccine in combination with nivolumab and ipilimumab were assessed as primary endpoints in an ongoing phase 1/2 study in patients with advanced metastatic solid tumors (NCT03639714). The individualized vaccine regimen was safe and well tolerated, with no dose-limiting toxicities. Treatment-related adverse events (TRAEs) >10% included pyrexia, fatigue, musculoskeletal and injection site pain and diarrhea. Serious TRAEs included one count each of pyrexia, duodenitis, increased transaminases and hyperthyroidism. The RP2D was 1012 viral particles (VP) ChAd68 and 30 µg samRNA. Secondary endpoints included immunogenicity, feasibility of manufacturing and overall survival (OS). Vaccine manufacturing was feasible, with vaccination inducing long-lasting neoantigen-specific CD8 T cell responses. Several patients with microsatellite-stable colorectal cancer (MSS-CRC) had improved OS. Exploratory biomarker analyses showed decreased circulating tumor DNA (ctDNA) in patients with prolonged OS. Although small study size limits statistical and translational analyses, the increased OS observed in MSS-CRC warrants further exploration in larger randomized studies.


Asunto(s)
Neoplasias Colorrectales , Pan troglodytes , Adenoviridae/genética , Animales , Neoplasias Colorrectales/tratamiento farmacológico , Fiebre , Humanos , ARN Mensajero/uso terapéutico
5.
Diversity (Basel) ; 14(2)2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35369669

RESUMEN

Many well-studied animal species use conspicuous, repetitive signals that attract both mates and predators. Orthopterans (crickets, katydids, and grasshoppers) are renowned for their acoustic signals. In Neotropical forests, however, many katydid species produce extremely short signals, totaling only a few seconds of sound per night, likely in response to predation by acoustically orienting predators. The rare signals of these katydid species raises the question of how they find conspecific mates in a structurally complex rainforest. While acoustic mechanisms, such as duetting, likely facilitate mate finding, we test the hypothesis that mate finding is further facilitated by colocalization on particular host plant species. DNA barcoding allows us to identify recently consumed plants from katydid stomach contents. We use DNA barcoding to test the prediction that katydids of the same species will have closely related plant species in their stomach. We do not find evidence for dietary specialization. Instead, katydids consumed a wide mix of plants within and across the flowering plants (27 species in 22 genera, 16 families, and 12 orders) with particular representation in the orders Fabales and Laurales. Some evidence indicates that katydids may gather on plants during a narrow window of rapid leaf out, but additional investigations are required to determine whether katydid mate finding is facilitated by gathering at transient food resources.

6.
Diabetes Ther ; 13(2): 355-365, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35103935

RESUMEN

INTRODUCTION: Adolescence and young adulthood is a challenging period, particularly for those living with chronic disease such as type 1 diabetes (T1D). Effective professional support is associated with better diabetes outcomes, but little is known about what determines healthcare professionals' decision-making for therapeutic intervention, and how to support this. Our study aimed to determine healthcare professionals' (HCPs) self-rated awareness, capability, opportunity and motivation to provide support for psychosocial issues in the management of T1D with adolescents and young adults; and to identify factors independently predictive of HCPs' perceptions of their confidence in, and perceived importance of, addressing psychosocial issues in this population. METHODS: Survey design was used, and data collected using an anonymous web-based questionnaire based on the Capability-Opportunity-Motivation Behaviour (COM-B) framework. The study was advertised to members of the Australian Diabetes Society, and National Association of Diabetes Centres. RESULTS: Of 98 respondents, 57 (58.2%) were female. Confidence and perceived importance summary scores were not significantly associated with demographic characteristics. HCPs agreed that both diabetes-dependent and external non-diabetes-specific influences were important components of psychosocial management, but self-rated themselves as less confident in their ability to provide care for these aspects. Few respondents regularly encountered psychosocial issues that they believed would lead to improved outcomes if addressed and not all HCPs knew how to access psychosocial support for their adolescent patients. CONCLUSION: Our findings indicate discrepancies between HCPs' self-rated capability and perceived motivation to provide support relating to psychosocial issues in the management of T1D for adolescents and young adults. Equitable opportunities are needed for training and support, to increase HCPs' understanding and hence their perceptions of the importance and of their confidence in addressing psychosocial issues, especially considering the high levels of risk of these young people for such problems.

7.
G3 (Bethesda) ; 10(11): 4103-4114, 2020 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-32988993

RESUMEN

The shade avoidance response is a set of developmental changes exhibited by plants to avoid shading by competitors, and is an important model of adaptive plant plasticity. While the mechanisms of sensing shading by other plants are well-known and appear conserved across plants, less is known about the developmental mechanisms that result in the diverse array of morphological and phenological responses to shading. This is particularly true for traits that appear later in plant development. Here we use a nested association mapping (NAM) population of Arabidopsis thaliana to decipher the genetic architecture of the shade avoidance response in late-vegetative and reproductive plants. We focused on four traits: bolting time, rosette size, inflorescence growth rate, and inflorescence size, found plasticity in each trait in response to shade, and detected 17 total QTL; at least one of which is a novel locus not previously identified for shade responses in Arabidopsis Using path analysis, we dissected each colocalizing QTL into direct effects on each trait and indirect effects transmitted through direct effects on earlier developmental traits. Doing this separately for each of the seven NAM populations in each environment, we discovered considerable heterogeneity among the QTL effects across populations, suggesting allelic series at multiple QTL or interactions between QTL and the genetic background or the environment. Our results provide insight into the development and variation in shade avoidance responses in Arabidopsis, and emphasize the value of directly modeling the relationships among traits when studying the genetics of complex developmental syndromes.


Asunto(s)
Arabidopsis , Alelos , Arabidopsis/genética , Inflorescencia , Fenotipo , Sitios de Carácter Cuantitativo
8.
J Psychiatr Ment Health Nurs ; 27(3): 205-210, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31793122

RESUMEN

WHAT IS KNOWN ON THIS SUBJECT?: Domestic and family violence contributes to mental distress and the development of mental illness and can reverberate throughout a person's life. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: Therapeutic work with people who experience domestic and family violence needs to take considerable time to allow the process to unfold. Understanding the triggers that cause past traumas to be re-experienced helps people to recognize and change their conditioned emotional responses. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Time needs to be invested to develop a secure and trusting relationship to enable a person to work through childhood experiences that have the potential to overwhelm. It is important for adults who have experienced childhood trauma to have an opportunity to process the abuse to help minimize its intrusion in their lives.


Asunto(s)
Adultos Sobrevivientes de Eventos Adversos Infantiles , Violencia Doméstica , Enfermería Psiquiátrica , Trauma Psicológico/terapia , Psicoterapia , Femenino , Humanos , Persona de Mediana Edad
9.
Artículo en Inglés | MEDLINE | ID: mdl-31552195

RESUMEN

Background: Trachoma, a neglected tropical disease, is the leading infectious cause of blindness and visual impairment worldwide. Host responses to ocular chlamydial infection resulting in chronic inflammation and expansion of non-chlamydial bacteria are hypothesized risk factors for development of active trachoma and conjunctival scarring. Methods: Ocular swabs from trachoma endemic populations in The Gambia were selected from archived samples for 16S sequencing and host conjunctival gene expression. We recruited children with active trachoma and adults with conjunctival scarring, alongside corresponding matched controls. Findings: In children, active trachoma was not associated with significant changes in the ocular microbiome. Haemophilus enrichment was associated with antimicrobial responses but not linked to active trachoma. Adults with scarring trachoma had a reduced ocular bacterial diversity compared to controls, with increased relative abundance of Corynebacterium. Increased abundance of Corynebacterium in scarring disease was associated with innate immune responses to the microbiota, dominated by altered mucin expression and increased matrix adhesion. Interpretation: In the absence of current Chlamydia trachomatis infection, changes in the ocular microbiome associate with differential expression of antimicrobial and inflammatory genes that impair epithelial cell health. In scarring trachoma, expansion of non-pathogenic bacteria such as Corynebacterium and innate responses are coincident, warranting further investigation of this relationship. Comparisons between active and scarring trachoma supported the relative absence of type-2 interferon responses in scarring, whilst highlighting a common suppression of re-epithelialization with altered epithelial and bacterial adhesion, likely contributing to development of scarring pathology.


Asunto(s)
Conjuntiva/microbiología , Células Epiteliales/microbiología , Microbiota , Tracoma/inmunología , Tracoma/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Bacterias/clasificación , Bacterias/efectos de los fármacos , Bacterias/genética , Estudios de Casos y Controles , Niño , Preescolar , Chlamydia trachomatis , Cicatriz/genética , Enfermedades de la Conjuntiva/inmunología , Enfermedades de la Conjuntiva/microbiología , Femenino , Gambia , Expresión Génica , Interacciones Microbiota-Huesped/efectos de los fármacos , Interacciones Microbiota-Huesped/genética , Interacciones Microbiota-Huesped/inmunología , Humanos , Inmunidad Innata , Lactante , Interferón gamma , Masculino , Microbiota/efectos de los fármacos , Microbiota/genética , Microbiota/inmunología , Persona de Mediana Edad , Tracoma/tratamiento farmacológico , Tracoma/genética , Adulto Joven
10.
PLoS Pathog ; 15(8): e1007981, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31449552

RESUMEN

Despite extensive research on the mechanisms of HLA-mediated immune control of HIV-1 pathogenesis, it is clear that much remains to be discovered, as exemplified by protective HLA alleles like HLA-B*81 which are associated with profound protection from CD4+ T cell decline without robust control of early plasma viremia. Here, we report on additional HLA class I (B*1401, B*57, B*5801, as well as B*81), and HLA class II (DQB1*02 and DRB1*15) alleles that display discordant virological and immunological phenotypes in a Zambian early infection cohort. HLA class I alleles of this nature were also associated with enhanced immune responses to conserved epitopes in Gag. Furthermore, these HLA class I alleles were associated with reduced levels of lipopolysaccharide (LPS) in the plasma during acute infection. Elevated LPS levels measured early in infection predicted accelerated CD4+ T cell decline, as well as immune activation and exhaustion. Taken together, these data suggest novel mechanisms for HLA-mediated immune control of HIV-1 pathogenesis that do not necessarily involve significant control of early viremia and point to microbial translocation as a direct driver of HIV-1 pathogenesis rather than simply a consequence.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Genes MHC Clase I/genética , Infecciones por VIH/inmunología , VIH-1/inmunología , VIH-1/patogenicidad , Lipopolisacáridos/deficiencia , Replicación Viral/inmunología , Alelos , Estudios de Cohortes , Femenino , Infecciones por VIH/genética , Infecciones por VIH/virología , VIH-1/genética , Humanos , Masculino , Linfocitos T Citotóxicos/inmunología , Carga Viral , Replicación Viral/genética
11.
PeerJ ; 7: e6808, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31110919

RESUMEN

BACKGROUND: Feeding habits are central to animal ecology, but it is often difficult to characterize the diet of organisms that are arboreal, nocturnal, rare, or highly mobile. Genetic analysis of gut contents is a promising approach for expanding our understanding of animal feeding habits. Here, we adapt a laboratory protocol for extracting and sequencing plant material from gut contents and apply it to Neotropical forest katydids (Orthoptera: Tettigoniidae) on Barro Colorado Island (BCI) in Panama. METHODS: Our approach uses three chloroplast primer sets that were previously developed to identify vegetation on BCI. We describe the utility and success rate of each primer set. We then test whether there is a significant difference in the amplification and sequencing success of gut contents based on the size or sex of the katydid, the time of day that it was caught, and the color of the extracted gut contents. RESULTS: We find that there is a significant difference in sequencing success as a function of gut color. When extracts were yellow, green, or colorless the likelihood of successfully amplifying DNA ranged from ~30-60%. When gut extracts were red, orange, or brown, amplification success was exceptionally low (0-8%). Amplification success was also higher for smaller katydids and tended to be more successful in katydids that were captured earlier in the night. Strength of the amplified product was indicative of the likelihood of sequencing success, with strong bands having a high likelihood of success. By anticipating which samples are most likely to succeed, we provide information useful for estimating the number of katydids that need to be collected and minimizing the costs of purifying, amplifying, and sequencing samples that are unlikely to succeed. This approach makes it possible to understand the herbivory patterns of these trophically important katydids and can be applied more broadly to understand the diet of other tropical herbivores.

13.
Nat Biotechnol ; 2018 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-30556813

RESUMEN

Neoantigens, which are expressed on tumor cells, are one of the main targets of an effective antitumor T-cell response. Cancer immunotherapies to target neoantigens are of growing interest and are in early human trials, but methods to identify neoantigens either require invasive or difficult-to-obtain clinical specimens, require the screening of hundreds to thousands of synthetic peptides or tandem minigenes, or are only relevant to specific human leukocyte antigen (HLA) alleles. We apply deep learning to a large (N = 74 patients) HLA peptide and genomic dataset from various human tumors to create a computational model of antigen presentation for neoantigen prediction. We show that our model, named EDGE, increases the positive predictive value of HLA antigen prediction by up to ninefold. We apply EDGE to enable identification of neoantigens and neoantigen-reactive T cells using routine clinical specimens and small numbers of synthetic peptides for most common HLA alleles. EDGE could enable an improved ability to develop neoantigen-targeted immunotherapies for cancer patients.

15.
Int J Ment Health Nurs ; 27(6): 1729-1741, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29762891

RESUMEN

Nursing students, regardless of setting, require skills in working with people with mental health issues. One way to provide students with learning opportunities within the context of limited undergraduate mental health content and lack of mental health placements is through employment as assistants in nursing (AIN). The purpose of the study was to investigate the use of AINs employed in an emergency department in South Australia to supervise (continuous observation) mental health consumers on inpatient treatment orders. Twenty-four participants took part in the study, with AINs (n = 8, all studying in an undergraduate nursing programme), nurse managers (n = 5), and nurses (n = 11) participating in semi-structured interviews. Data were analysed using thematic analysis. Themes focused on (i) the AIN role, their practice, boundaries or restrictions of their role, and the image consumers have of AINs; (ii) learning through experience, where the AIN role was a practical opportunity to learn and apply knowledge obtained through university studies; and (iii) support, which focused on how AINs worked with nursing staff as part of the healthcare team. Overall, participants believed that AINs played an important role in the ED in supervising consumers on involuntary mental health treatment orders, where their unique role was seen to facilitate more positive consumer experiences. The AIN role is one way for nursing students to develop skills in working with people with mental health issues.


Asunto(s)
Servicio de Urgencia en Hospital , Asistentes de Enfermería , Enfermería Psiquiátrica/educación , Estudiantes de Enfermería , Adulto , Servicio de Urgencia en Hospital/organización & administración , Femenino , Humanos , Masculino , Adulto Joven
16.
PLoS One ; 13(5): e0197298, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29746555

RESUMEN

BACKGROUND: Human Herpes Virus 8 (HHV8) can cause Kaposi's Sarcoma (KS) in immunosuppressed individuals. However, little is known about the association between chemotherapy or hematopoietic stem cell transplantation (HSCT), circulating HHV8 DNA levels, and clinical KS in HIV-1-infected individuals with various malignancies. Therefore, we examined the associations between various malignancies, systemic cancer chemotherapy, T cell phenotypes, and circulating HHV8 DNA in 29 HIV-1-infected participants with concomitant KS or other cancer diagnoses. METHODS: We quantified HHV8 plasma viral loads and cell-associated HHV8 DNA and determined the relationship between circulating HHV8 DNA and lymphocyte counts, and markers of early and late lymphocyte activation, proliferation and exhaustion. RESULTS: There were no significant differences in plasma HHV8 DNA levels between baseline and post-chemotherapy time points or with the presence or absence of clinical KS. However, in two participants circulating HHV8 DNA increased following treatment for KS or HSCT for lymphoma,. We observed an approximately 2-log10 reduction in plasma HHV8 DNA in an individual with KS and multicentric Castleman disease following rituximab monotherapy. Although individuals with clinical KS had lower mean CD4+ T cell counts and percentages as expected, there were no significant associations with these factors and plasma HHV8 levels. We identified increased proportions of CD8+ and CD4+ T cells expressing CD69 (P = 0.01 & P = 0.04 respectively), and increased CD57 expression on CD4+ T cells (P = 0.003) in participants with detectable HHV8. CONCLUSION: These results suggest there is a complex relationship between circulating HHV8 DNA and tissue-based disease in HIV-1 and HHV8 co-infected individuals with various malignancies.


Asunto(s)
Infecciones por VIH/complicaciones , Herpesvirus Humano 8/fisiología , Neoplasias/complicaciones , Neoplasias/terapia , Sarcoma de Kaposi/complicaciones , Sarcoma de Kaposi/terapia , Antineoplásicos/uso terapéutico , Enfermedad de Castleman/complicaciones , Enfermedad de Castleman/terapia , Enfermedad de Castleman/virología , Terapia Combinada , ADN Viral/sangre , Femenino , Infecciones por VIH/virología , Humanos , Recuento de Linfocitos , Masculino , Neoplasias/virología , Sarcoma de Kaposi/virología , Trasplante de Células Madre , Carga Viral
17.
PLoS One ; 12(10): e0184496, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29020090

RESUMEN

Antigen-specific T-cells are highly variable, spanning potent antiviral efficacy and damaging auto-reactivity. In virus infections, identifying the most efficacious responses is critical to vaccine design. However, current methods depend on indirect measures or on ex vivo expanded CTL clones. We here describe a novel application of cytotoxic saporin-conjugated tetramers to kill antigen-specific T-cells without significant off-target effects. The relative efficacy of distinct antiviral CD8+ T-cell specificity can be directly assessed via antigen-specific CD8+ T-cell depletion. The utility of these reagents is demonstrated here in identifying the CD8+ T-cell specificity most effective in preventing HIV progression in HIV-infected HLA-B*27-positive immune controllers.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Multimerización de Proteína , Proteínas Inactivadoras de Ribosomas Tipo 1/uso terapéutico , Antivirales/farmacología , Linfocitos T CD8-positivos/efectos de los fármacos , Endocitosis/efectos de los fármacos , Humanos , Depleción Linfocítica , Saporinas
18.
J Infect Dis ; 216(2): 254-262, 2017 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-28838149

RESUMEN

Background: Systemic chemotherapies for various malignancies have been shown to significantly, yet transiently, decrease numbers of CD4+ T lymphocytes, a major reservoir for human immunodeficiency virus type 1 (HIV-1) infection. However, little is known about the impact of cytoreductive chemotherapy on HIV-1 reservoir dynamics, persistence, and immune responses. Methods: We investigated the changes in peripheral CD4+ T-cell-associated HIV-1 DNA and RNA levels, lymphocyte activation, viral population structure, and virus-specific immune responses in a longitudinal cohort of 15 HIV-1-infected individuals receiving systemic chemotherapy or subsequent autologous stem cell transplantation for treatment of hematological malignancies and solid tumors. Results: Despite a transient reduction in CD4+ T cells capable of harboring HIV-1, a 1.7- and 3.3-fold increase in mean CD4+ T-cell-associated HIV-1 RNA and DNA, respectively, were observed months following completion of chemotherapy in individuals on antiretroviral therapy. We also observed changes in CD4+ T-cell population diversity and clonal viral sequence expansion during CD4+ T-cell reconstitution following chemotherapy cessation. Finally, HIV-1 DNA was preferentially, and in some cases exclusively, detected in cytomegalovirus (CMV)- and Epstein-Barr virus (EBV)-responsive CD4+ T cells following chemotherapy. Conclusions: Expansion of HIV-infected CMV/EBV-specific CD4 + T cells may contribute to maintenance of the HIV DNA reservoir following chemotherapy.


Asunto(s)
Terapia Antirretroviral Altamente Activa , Linfocitos T CD4-Positivos/inmunología , Infecciones por VIH/tratamiento farmacológico , Neoplasias/complicaciones , Citomegalovirus , Infecciones por Citomegalovirus , ADN Viral/análisis , Quimioterapia , Femenino , VIH-1 , Herpesvirus Humano 4 , Humanos , Activación de Linfocitos , Masculino , Neoplasias/terapia , Neoplasias/virología , Estudios Prospectivos , ARN Viral/análisis , Trasplante de Células Madre , Carga Viral , Replicación Viral
19.
Front Med (Lausanne) ; 4: 251, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29410954

RESUMEN

BACKGROUND: Several non-chlamydial microbial pathogens are associated with clinical signs of active trachoma in trachoma-endemic communities with a low prevalence of ocular Chlamydia trachomatis (Ct) infection. In the Solomon Islands, the prevalence of Ct among children is low despite the prevalence of active trachoma being moderate. Therefore, we set out to investigate whether active trachoma was associated with a common non-chlamydial infection or with a dominant polymicrobial community dysbiosis in the Solomon Islands. METHODS: We studied DNA from conjunctival swabs collected from 257 Solomon Islanders with active trachoma and matched controls. Droplet digital PCR was used to test for pathogens suspected to be able to induce follicular conjunctivitis. Polymicrobial community diversity and composition were studied by sequencing of hypervariable regions of the 16S ribosomal ribonucleic acid gene in a subset of 54 cases and 53 controls. RESULTS: Although Ct was associated with active trachoma, the number of infections was low (cases, 3.9%; controls, 0.4%). Estimated prevalence (cases and controls, respectively) of each non-chlamydial infection was as follows: Staphylococcus aureus: 1.9 and 1.9%, Adenoviridae: 1.2 and 1.2%, coagulase-negative Staphylococcus: 5.8 and 4.3%, Haemophilus influenzae: 7.4 and 11.7%, Moraxella catarrhalis: 2.3 and 4.7%, and Streptococcus pneumoniae: 7.0 and 6.2%. There was no statistically significant association between the clinical signs of trachoma and the presence or load of any of the non-Ct infections that were assayed. Interindividual variations in the conjunctival microbiome were characterized by differences in the levels of Corynebacterium, Propionibacterium, Helicobacter, and Paracoccus, but diversity and relative abundance of these specific genera did not differ significantly between cases and controls. DISCUSSION: It is unlikely that the prevalent trachoma-like follicular conjunctivitis in this region of the Solomon Islands has a dominant bacterial etiology. Before implementing community-wide azithromycin distribution for trachoma, policy makers should consider that clinical signs of trachoma can be observed in the absence of any detectable azithromycin-susceptible organism.

20.
J Int AIDS Soc ; 19(1): 21136, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27938646

RESUMEN

INTRODUCTION: An effective prophylactic vaccine against HIV will need to elicit antibody responses capable of recognizing and neutralizing rapidly evolving antigenic regions. The immunologic milieu associated with development of neutralizing antibody breadth remains to be fully defined. In this study, we sought to identify immunological signatures associated with neutralization breadth in HIV controllers. We applied an immune monitoring approach to analyze markers of T cell and myeloid cell activation by flow cytometry, comparing broad neutralizers with low- and non-neutralizers using multivariate and univariate analyses. METHODS: Antibody neutralization breadth was determined, and cryopreserved peripheral blood mononuclear cells were stained for T cell and myeloid cell activation markers. Subjects were grouped according to neutralization breadth, and T cell and myeloid cell activation was analyzed by partial least squares discriminant analysis to determine immune signatures associated with high neutralization breadth. RESULTS: We show that neutralization breadth in HIV viraemic controllers (VC) was strongly associated with increased frequencies of CD8+CD57+ T cells and that this association was independent of viral load, CD4 count and time since HIV diagnosis. CONCLUSIONS: Our data show elevated frequencies of CD8+CD57+ T cells in VC who develop neutralization breadth against HIV. This immune signature could serve as a potential biomarker of neutralization breadth and should be further investigated in other HIV-positive cohorts and in HIV vaccine trials.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Linfocitos T CD8-positivos/inmunología , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/inmunología , Vacunas contra el SIDA/inmunología , Adulto , Anticuerpos Neutralizantes/sangre , Recuento de Linfocito CD4 , Antígenos CD57 , Femenino , Anticuerpos Anti-VIH/sangre , Infecciones por VIH/virología , Humanos , Inmunogenicidad Vacunal , Leucocitos Mononucleares , Masculino , Persona de Mediana Edad , Carga Viral , Viremia/inmunología
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