RESUMEN
HIV infection is associated with gut dysbiosis, and microbiome variability may affect HIV control when antiretroviral therapy (ART) is stopped. The TLR7 agonist, vesatolimod, was previously associated with a modest delay in viral rebound following analytical treatment interruption in HIV controllers (HCs). Using a retrospective analysis of fecal samples from HCs treated with vesatolimod or placebo (NCT03060447), people with chronic HIV (CH; NCT02858401) or without HIV (PWOH), we examined fecal microbiome profile in HCs before/after treatment, and in CH and PWOH. Microbiome diversity and abundance were compared between groups to investigate the association between specific phyla/species, immune biomarkers, and viral outcomes during treatment interruption. Although there were no significant differences in gut microbiome diversity between people with and without HIV, HCs, and CH shared common features that distinguished them from PWOH. there was a trend toward greater microbiome diversity among HCs. Treatment with vesatolimod reduced dysbiosis in HCs. Firmicutes positively correlated with T-cell activation, while Bacteroidetes and Euryarchaeota inversely correlated with TLR7-mediated immune activation. Specific types of fecal microbiome abundance (e.g. Alistipes putredinis) positively correlated with HIV rebound. In conclusion, variability in the composition of the fecal microbiome is associated with markers of immune activation following vesatolimod treatment and ART interruption.
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Disbiosis , Heces , Microbioma Gastrointestinal , Infecciones por VIH , Humanos , Infecciones por VIH/inmunología , Infecciones por VIH/microbiología , Infecciones por VIH/tratamiento farmacológico , Heces/microbiología , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/inmunología , Masculino , Femenino , Adulto , Disbiosis/microbiología , Disbiosis/inmunología , Persona de Mediana Edad , Estudios Retrospectivos , Carga Viral/efectos de los fármacos , Receptor Toll-Like 7/inmunología , VIH-1/inmunología , PteridinasRESUMEN
BACKGROUND: The diagnosis of infective endocarditis (IE) can be difficult, particularly if blood cultures fail to yield a pathogen. This study evaluates the potential utility of microbial cell-free DNA (mcfDNA) as a tool to identify the microbial etiology of IE. METHODS: Blood samples from patients with suspected IE were serially collected. mcfDNA was extracted from plasma and underwent next-generation sequencing. Reads were aligned against a library containing DNA sequences belonging to >1400 different pathogens. mcfDNA from organisms present above a statistical threshold were reported and quantified in molecules per milliliter (MPM). Additional mcfDNA was collected on each subject every 2-3 days for a total of 7 collections or until discharge. RESULTS: Of 30 enrolled patients with suspected IE, 23 had definite IE, 2 had possible IE, and IE was rejected in 5 patients by modified Duke Criteria. Only the 23 patients with definite IE were included for analysis. Both mcfDNA and blood cultures achieved a sensitivity of 87%. The median duration of positivity from antibiotic treatment initiation was estimated to be approximately 38.1 days for mcfDNA versus 3.7 days for blood culture (proportional odds, 2.952; P = .02771), using a semiparametric survival analysis. mcfDNA (log10) levels significantly declined (-0.3 MPM log10 units, 95% credible interval -0.45 to -0.14) after surgical source control was performed (pre- vs postprocedure, posterior probability >0.99). CONCLUSION: mcfDNA accurately identifies the microbial etiology of IE. Sequential mcfDNA levels may ultimately help to individualize therapy by estimating a patient's burden of infection and response to treatment.
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Ácidos Nucleicos Libres de Células , Endocarditis Bacteriana , Endocarditis , Humanos , Cultivo de Sangre , Antibacterianos/uso terapéutico , Endocarditis Bacteriana/diagnóstico , Endocarditis/diagnóstico , Endocarditis/tratamiento farmacológicoRESUMEN
BACKGROUND: Microbial cell-free DNA (mcfDNA) sequencing of plasma can identify the presence of a pathogen in a host. In this study, we evaluated the duration of pathogen detection by mcfDNA sequencing vs conventional blood culture in patients with bacteremia. METHODS: Blood samples from patients with culture-confirmed bloodstream infection were collected within 24 hours of the index positive blood culture and 48 to 72 hours thereafter. mcfDNA was extracted from plasma, and next-generation sequencing was applied. Reads were aligned against a curated pathogen database. Statistical significance was defined with Bonferroni adjustment for multiple comparisons (Pâ <â .0033). RESULTS: A total of 175 patients with Staphylococcus aureus bacteremia (nâ =â 66), gram-negative bacteremia (nâ =â 74), or noninfected controls (nâ =â 35) were enrolled. The overall sensitivity of mcfDNA sequencing compared with index blood culture was 89.3% (125 of 140), and the specificity was 74.3%. Among patients with bacteremia, pathogen-specific mcfDNA remained detectable for significantly longer than conventional blood cultures (median 15 days vs 2 days; Pâ <â .0001). Each additional day of mcfDNA detection significantly increased the odds of metastatic infection (odds ratio, 2.89; 95% confidence interval, 1.53-5.46; Pâ =â .0011). CONCLUSIONS: Pathogen mcfDNA identified the bacterial etiology of bloodstream infection for a significantly longer interval than conventional cultures, and its duration of detection was associated with increased risk for metastatic infection. mcfDNA could play a role in the diagnosis of partially treated endovascular infections.
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Bacteriemia , Ácidos Nucleicos Libres de Células , Sepsis , Infecciones Estafilocócicas , Bacteriemia/microbiología , Cultivo de Sangre , Humanos , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/genéticaRESUMEN
Background: Antiretroviral therapy (ART) for HIV-1 treatment has improved lifespan but requires lifelong adherence for people living with HIV (PLWH), highlighting the need for a cure. Evaluation of potential cure strategies requires analytic treatment interruption (ATI) with close monitoring of viral rebound. Predictive biomarkers for HIV-1 rebound and/or duration of control during ATI will facilitate these HIV cure trials while minimizing risks. Available evidence suggests that host immune, glycomic, lipid, and metabolic markers of inflammation may be associated with HIV-1 persistence in PLWH who are treated during chronic HIV-1 infection. Methods: We conducted post-hoc analysis of HIV controllers who could maintain low levels of plasma HIV-1 without ART in a phase 1b vesatolimod trial. Baseline and pre-ATI levels of immune, glycomic, lipidomic, and metabolomic markers were tested for association with ATI outcomes (time of HIV-1 rebound to 200 copies/mL and 1,000 copies/mL, duration of HIV-1 RNA ≤400 copies/mL and change in intact proviral HIV-1 DNA during ATI) using Spearman's correlation and Cox proportional hazards model. Results: Higher levels of CD69+CD8+ T-cells were consistently associated with shorter time to HIV-1 rebound at baseline and pre-ATI. With few exceptions, baseline fucosylated, non-galactosylated, non-sialylated, bisecting IgG N-glycans were associated with shorter time to HIV rebound and duration of control as with previous studies. Baseline plasma MPA and HPA binding glycans and non-galactosylated/non-sialylated glycans were associated with longer time to HIV rebound, while baseline multiply-galactosylated glycans and sialylated glycans, GNA-binding glycans, NPA-binding glycans, WGA-binding glycans, and bisecting GlcNAc glycans were associated with shorter time to HIV rebound and duration of control. Fourteen bioactive lipids had significant baseline associations with longer time to rebound and duration of control, and larger intact proviral HIV-1 DNA changes; additionally, three baseline bioactive lipids were associated with shorter time to first rebound and duration of control. Conclusion: Consistent with studies in HIV non-controllers, proinflammatory glycans, lipids, and metabolites were generally associated with shorter duration of HIV-1 control. Notable differences were observed between HIV controllers vs. non-controllers in some specific markers. For the first time, exploratory biomarkers of ATI viral outcomes in HIV-controllers were investigated but require further validation.
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Biomarcadores , Infecciones por VIH , VIH-1 , Carga Viral , Humanos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Infecciones por VIH/sangre , Infecciones por VIH/virología , Biomarcadores/sangre , VIH-1/inmunología , Masculino , Adulto , Femenino , Fármacos Anti-VIH/uso terapéutico , Persona de Mediana Edad , ARN Viral/sangreRESUMEN
Biofilms are structured communities of microbial cells embedded in a self-produced matrix of extracellular polymeric substances. Biofilms are associated with many health issues in humans, including chronic wound infections and tooth decay. Current antimicrobials are often incapable of disrupting the polymeric biofilm matrix and reaching the bacteria within. Alternative approaches are needed. Here, we described a complex structure of a dextran-coated gold-in-gold cage nanoparticle that enabled photoacoustic and photothermal properties for biofilm detection and treatment. Activation of these nanoparticles with a near infrared laser could selectively detect and kill biofilm bacteria with precise spatial control and in a short timeframe. We observed a strong biocidal effect against both Streptococcus mutans and Staphylococcus aureus biofilms in mouse models of oral plaque and wound infections, respectively. These effects were over 100 times greater than those seen with chlorhexidine, a conventional antimicrobial agent. Moreover, this approach did not adversely affect surrounding tissues. We concluded that photothermal ablation using theranostic nanoparticles is a rapid, precise, and nontoxic method to detect and treat biofilm-associated infections.
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Nanopartículas , Técnicas Fotoacústicas , Infección de Heridas , Animales , Ratones , Antibacterianos , Biopelículas , Oro/farmacología , Oro/química , Nanopartículas/química , Medicina de PrecisiónRESUMEN
Biofilms are structured communities of microbial cells embedded in a self-produced matrix of extracellular polymeric substances. Biofilms are associated with many health issues in humans, including chronic wound infections and tooth decay. Current antimicrobials are often incapable of disrupting the polymeric biofilm matrix and reaching the bacteria within. Alternative approaches are needed. Here, we describe a unique structure of dextran coated gold in a gold cage nanoparticle that enables photoacoustic and photothermal properties for biofilm detection and treatment. Activation of these nanoparticles with a near infrared laser can selectively detect and kill biofilm bacteria with precise spatial control and in a short timeframe. We observe a strong biocidal effect against both Streptococcus mutans and Staphylococcus aureus biofilms in mouse models of oral plaque and wound infections respectively. These effects were over 100 times greater than that seen with chlorhexidine, a conventional antimicrobial agent. Moreover, this approach did not adversely affect surrounding tissues. We conclude that photothermal ablation using theranostic nanoparticles is a rapid, precise, and non-toxic method to detect and treat biofilm-associated infections.
RESUMEN
Chronic wounds infected by Pseudomonas aeruginosa (Pa) are characterized by disease progression and increased mortality. We reveal Pf, a bacteriophage produced by Pa that delays healing of chronically infected wounds in human subjects and animal models of disease. Interestingly, impairment of wound closure by Pf is independent of its effects on Pa pathogenesis. Rather, Pf impedes keratinocyte migration, which is essential for wound healing, through direct inhibition of CXCL1 signaling. In support of these findings, a prospective cohort study of 36 human patients with chronic Pa wound infections reveals that wounds infected with Pf-positive strains of Pa are more likely to progress in size compared with wounds infected with Pf-negative strains. Together, these data implicate Pf phage in the delayed wound healing associated with Pa infection through direct manipulation of mammalian cells. These findings suggest Pf may have potential as a biomarker and therapeutic target in chronic wounds.
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Inovirus , Infecciones por Pseudomonas , Infección de Heridas , Animales , Biopelículas , Humanos , Mamíferos , Estudios Prospectivos , Pseudomonas , Infecciones por Pseudomonas/terapia , Pseudomonas aeruginosa , Cicatrización de Heridas , Infección de Heridas/terapiaRESUMEN
Bacteriophages have attracted extensive interest in vaccine design. This includes the use of phage display technology to select antigens, the use of engineered phages displaying target antigens in vaccine formulations, and phage DNA vaccines. However, the development of these approaches is limited in part by uncertainty regarding the underlying mechanisms by which phages elicit immunity. This has stymied the clinical development of this technology. Here we review the immunology of phage vaccines and highlight the gaps in our knowledge regarding the underlying mechanisms. First, we review the basic biology of phages and their use in vaccines. Next we discuss what is known about the mechanisms of immunity against engineered phages and phage DNA. Finally, we highlight the gaps in our understanding regarding the immunogenicity of these preparations. We argue that mechanistic insight into the immunology of phage vaccines is essential for the further development and clinical utility of these technologies.
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Bacteriófagos , Vacunas , Bacteriófagos/genética , Técnicas de Visualización de Superficie CelularRESUMEN
Increasing rates of infection by antibiotic resistant bacteria have led to a resurgence of interest in bacteriophage (phage) therapy. Several phage therapy studies in animals and humans have been completed over the last two decades. We conducted a systematic review of safety and toxicity data associated with phage therapy in both animals and humans reported in English language publications from 2008-2021. Overall, 69 publications met our eligibility criteria including 20 animal studies, 35 clinical case reports or case series, and 14 clinical trials. After summarizing safety and toxicity data from these publications, we discuss potential approaches to optimize safety and toxicity monitoring with the therapeutic use of phage moving forward. In our systematic review of the literature, we found some adverse events associated with phage therapy, but serious events were extremely rare. Comprehensive and standardized reporting of potential toxicities associated with phage therapy has generally been lacking in the published literature. Structured safety and tolerability endpoints are necessary when phages are administered as anti-infective therapeutics.
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Infecciones Bacterianas/terapia , Ensayos Clínicos como Asunto , Terapia de Fagos/efectos adversos , Terapia de Fagos/métodos , Animales , Bacteriófagos/patogenicidad , Modelos Animales de Enfermedad , Humanos , RatonesRESUMEN
Type III interferons have been touted as promising therapeutics in outpatients with coronavirus disease 2019 (COVID-19). We conducted a randomized, single-blind, placebo-controlled trial (NCT04331899) in 120 outpatients with mild to moderate COVID-19 to determine whether a single, 180 mcg subcutaneous dose of Peginterferon Lambda-1a (Lambda) within 72 hours of diagnosis could shorten the duration of viral shedding (primary endpoint) or symptoms (secondary endpoint). In both the 60 patients receiving Lambda and 60 receiving placebo, the median time to cessation of viral shedding was 7 days (hazard ratio [HR] = 0.81; 95% confidence interval [CI] 0.56 to 1.19). Symptoms resolved in 8 and 9 days in Lambda and placebo, respectively, and symptom duration did not differ significantly between groups (HR 0.94; 95% CI 0.64 to 1.39). Both Lambda and placebo were well-tolerated, though liver transaminase elevations were more common in the Lambda vs. placebo arm (15/60 vs 5/60; p = 0.027). In this study, a single dose of subcutaneous Peginterferon Lambda-1a neither shortened the duration of SARS-CoV-2 viral shedding nor improved symptoms in outpatients with uncomplicated COVID-19.
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Antivirales/administración & dosificación , Tratamiento Farmacológico de COVID-19 , Interleucinas/administración & dosificación , Polietilenglicoles/administración & dosificación , Adulto , Anciano , COVID-19/virología , Femenino , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/fisiología , Método Simple Ciego , Insuficiencia del Tratamiento , Esparcimiento de Virus/efectos de los fármacos , Adulto JovenRESUMEN
A coat of pericellular hyaluronan surrounds mature dendritic cells (DC) and contributes to cell-cell interactions. We asked whether 4-methylumbelliferone (4MU), an oral inhibitor of HA synthesis, could inhibit antigen presentation. We find that 4MU treatment reduces pericellular hyaluronan, destabilizes interactions between DC and T-cells, and prevents T-cell proliferation in vitro and in vivo. These effects were observed only when 4MU was added prior to initial antigen presentation but not later, consistent with 4MU-mediated inhibition of de novo antigenic responses. Building on these findings, we find that 4MU delays rejection of allogeneic pancreatic islet transplant and allogeneic cardiac transplants in mice and suppresses allogeneic T-cell activation in human mixed lymphocyte reactions. We conclude that 4MU, an approved drug, may have benefit as an adjunctive agent to delay transplantation rejection.
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Células Dendríticas/citología , Rechazo de Injerto/prevención & control , Ácido Hialurónico/biosíntesis , Himecromona/administración & dosificación , Linfocitos T Reguladores/citología , Animales , Presentación de Antígeno/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Modelos Animales de Enfermedad , Rechazo de Injerto/inmunología , Trasplante de Corazón/efectos adversos , Humanos , Himecromona/farmacología , Leucocitos/citología , Leucocitos/efectos de los fármacos , Leucocitos/inmunología , Ratones , Trasplante de Páncreas/efectos adversos , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/metabolismo , Trasplante HomólogoRESUMEN
Pseudomonas aeruginosa (P. aeruginosa) is a major nosocomial pathogen of increasing relevance to human health and disease, particularly in the setting of chronic wound infections in diabetic and hospitalized patients. There is an urgent need for chronic infection models to aid in the investigation of wound pathogenesis and the development of new therapies against this pathogen. Here, we describe a protocol that uses delayed inoculation 24 hours after full-thickness excisional wounding. The infection of the provisional wound matrix present at this time forestalls either rapid clearance or dissemination of infection and instead establishes chronic infection lasting 7-10 days without the need for implantation of foreign materials or immune suppression. This protocol mimics a typical temporal course of post-operative infection in humans. The use of a luminescent P. aeruginosa strain (PAO1:lux) allows for quantitative daily assessment of bacterial burden for P. aeruginosa wound infections. This novel model may be a useful tool in the investigation of bacterial pathogenesis and the development of new therapies for chronic P. aeruginosa wound infections.
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Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/patogenicidad , Infección de Heridas/microbiología , Animales , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos C57BL , Infecciones por Pseudomonas/patología , Infección de Heridas/patologíaRESUMEN
Pf bacteriophage are temperate phages that infect the bacterium Pseudomonas aeruginosa, a major cause of chronic lung infections in cystic fibrosis (CF) and other settings. Pf and other temperate phages have evolved complex, mutualistic relationships with their bacterial hosts that impact both bacterial phenotypes and chronic infection. We and others have reported that Pf phages are a virulence factor that promote the pathogenesis of P. aeruginosa infections in animal models and are associated with worse skin and lung infections in humans. Here we review the biology of Pf phage and what is known about its contributions to pathogenesis and clinical disease. First, we review the structure, genetics, and epidemiology of Pf phage. Next, we address the diverse and surprising ways that Pf phages contribute to P. aeruginosa phenotypes including effects on biofilm formation, antibiotic resistance, and motility. Then, we cover data indicating that Pf phages suppress mammalian immunity at sites of bacterial infection. Finally, we discuss recent literature implicating Pf in chronic P. aeruginosa infections in CF and other settings. Together, these reports suggest that Pf bacteriophage have direct effects on P. aeruginosa infections and that temperate phages are an exciting frontier in microbiology, immunology, and human health.
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Bacteriófagos/fisiología , Infecciones por Pseudomonas/inmunología , Pseudomonas aeruginosa/fisiología , Animales , Biopelículas , Enfermedad Crónica , Farmacorresistencia Microbiana , Humanos , Mamíferos , Infecciones por Pseudomonas/transmisión , Infecciones por Pseudomonas/virología , VirulenciaRESUMEN
Bacteriophage are abundant at sites of bacterial infection, but their effects on mammalian hosts are unclear. We have identified pathogenic roles for filamentous Pf bacteriophage produced by Pseudomonas aeruginosa (Pa) in suppression of immunity against bacterial infection. Pf promote Pa wound infection in mice and are associated with chronic human Pa wound infections. Murine and human leukocytes endocytose Pf, and internalization of this single-stranded DNA virus results in phage RNA production. This triggers Toll-like receptor 3 (TLR3)- and TIR domain-containing adapter-inducing interferon-ß (TRIF)-dependent type I interferon production, inhibition of tumor necrosis factor (TNF), and the suppression of phagocytosis. Conversely, immunization of mice against Pf prevents Pa wound infection. Thus, Pf triggers maladaptive innate viral pattern-recognition responses, which impair bacterial clearance. Vaccination against phage virions represents a potential strategy to prevent bacterial infection.
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Tolerancia Inmunológica , Fagocitosis/inmunología , Infecciones por Pseudomonas/inmunología , Fagos Pseudomonas/fisiología , Pseudomonas aeruginosa/patogenicidad , Pseudomonas aeruginosa/virología , Infección de Heridas/inmunología , Proteínas Adaptadoras del Transporte Vesicular/genética , Proteínas Adaptadoras del Transporte Vesicular/inmunología , Animales , Anticuerpos Antivirales/inmunología , Humanos , Interferones/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Fagos Pseudomonas/inmunología , Receptor Toll-Like 3/genética , Receptor Toll-Like 3/inmunología , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
CD25CD4 regulatory T cells (Treg) regulate peripheral self-tolerance and possess the ability to suppress antitumor responses, which may explain the poor clinical response of cancer patients undergoing active immunization protocols, and provides the rationale for neutralizing Treg cells in vivo to strengthen local antitumor immune responses. Because interleukin-2 (IL-2) mediates tumor regression in about 15% of treated patients but simultaneously increases Treg cells, we hypothesized that transient elimination of Treg cells will enhance the clinical effectiveness of IL-2 therapy. In the current study, 5 patients with metastatic melanoma who were refractory to prior IL-2 received a lymphodepleting preparative regimen followed by the adoptive transfer of autologous lymphocytes depleted of CD25 Treg cells and high-dose IL-2 administration. CD25 cells were eliminated from patient leukapheresis samples using a clinical-grade, large-scale immunomagnetic system, leaving CD8 and CD25CD4 T cells intact. In the early aftermath of CD25 Treg cell-depleted cell infusion, CD25FOXP3+ CD4 Treg cells rapidly repopulated the peripheral blood of treated patients with 18% to 63% of CD4 T cells expressing FOXP3. Recovering CD25CD4 T cells exhibited suppressive activity against CD25CD4 effector T-cell proliferation in vitro. No patient experienced objective tumor regression or autoimmunity. Our results indicate that in vivo transfer of autologous CD25-depleted mononuclear populations to lymphopenic patients in combination with high-dose IL-2 is not sufficient to mediate prolonged reduction of Treg cells after IL-2 administration.
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Quimioterapia/métodos , Inmunoterapia/métodos , Subunidad alfa del Receptor de Interleucina-2/biosíntesis , Interleucina-2/metabolismo , Leucocitos Mononucleares/metabolismo , Adulto , Antineoplásicos/farmacología , Femenino , Humanos , Leucocitos Mononucleares/inmunología , Masculino , Melanoma/patología , Persona de Mediana Edad , Metástasis de la Neoplasia , Neoplasias Cutáneas/patología , Linfocitos T Reguladores/metabolismoRESUMEN
Through the adoptive transfer of lymphocytes after host immunodepletion, it is possible to mediate objective cancer regression in human patients with metastatic melanoma. However, the generation of tumor-specific T cells in this mode of immunotherapy is often limiting. Here we report the ability to specifically confer tumor recognition by autologous lymphocytes from peripheral blood by using a retrovirus that encodes a T cell receptor. Adoptive transfer of these transduced cells in 15 patients resulted in durable engraftment at levels exceeding 10% of peripheral blood lymphocytes for at least 2 months after the infusion. We observed high sustained levels of circulating, engineered cells at 1 year after infusion in two patients who both demonstrated objective regression of metastatic melanoma lesions. This study suggests the therapeutic potential of genetically engineered cells for the biologic therapy of cancer.