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1.
Nat Immunol ; 21(3): 309-320, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31953534

RESUMEN

Tissue-resident memory T cells (TRM cells) are critical for cellular immunity to respiratory pathogens and reside in both the airways and the interstitium. In the present study, we found that the airway environment drove transcriptional and epigenetic changes that specifically regulated the cytolytic functions of airway TRM cells and promoted apoptosis due to amino acid starvation and activation of the integrated stress response. Comparison of airway TRM cells and splenic effector-memory T cells transferred into the airways indicated that the environment was necessary to activate these pathways, but did not induce TRM cell lineage reprogramming. Importantly, activation of the integrated stress response was reversed in airway TRM cells placed in a nutrient-rich environment. Our data defined the genetic programs of distinct lung TRM cell populations and show that local environmental cues altered airway TRM cells to limit cytolytic function and promote cell death, which ultimately leads to fewer TRM cells in the lung.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Reprogramación Celular/genética , Reprogramación Celular/inmunología , Epigénesis Genética/inmunología , Memoria Inmunológica/genética , Pulmón/inmunología , Animales , Apoptosis/inmunología , Linfocitos T CD8-positivos/citología , Supervivencia Celular/genética , Supervivencia Celular/inmunología , Microambiente Celular/genética , Microambiente Celular/inmunología , Femenino , Pulmón/citología , Masculino , Ratones , Ratones Endogámicos C57BL , Infecciones por Orthomyxoviridae/genética , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/patología
2.
Immunity ; 45(3): 656-668, 2016 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-27653601

RESUMEN

Infection with HIV persists despite suppressive antiretroviral therapy (ART), and treatment interruption results in rapid viral rebound. Antibody-mediated CD8(+) lymphocyte depletion in simian immunodeficiency virus (SIV)-infected rhesus macaques (RMs) shows that these cells contribute to viral control in untreated animals. However, the contribution of CD8(+) lymphocytes to maintaining viral suppression under ART remains unknown. Here, we have shown that in SIV-infected RMs treated with short-term (i.e., 8-32 week) ART, depletion of CD8(+) lymphocytes resulted in increased plasma viremia in all animals and that repopulation of CD8(+) T cells was associated with prompt reestablishment of virus control. Although the number of SIV-DNA-positive cells remained unchanged after CD8 depletion and reconstitution, the frequency of SIV-infected CD4(+) T cells before depletion positively correlated with both the peak and area under the curve of viremia after depletion. These results suggest a role for CD8(+) T cells in controlling viral production during ART, thus providing a rationale for exploring immunotherapeutic approaches in ART-treated HIV-infected individuals.


Asunto(s)
Antirretrovirales/farmacología , Linfocitos T CD8-positivos/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Animales , Anticuerpos Antivirales/inmunología , Terapia Antirretroviral Altamente Activa/métodos , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Femenino , Depleción Linfocítica/métodos , Macaca mulatta , Masculino , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/efectos de los fármacos , Carga Viral/efectos de los fármacos , Carga Viral/inmunología , Viremia/tratamiento farmacológico , Viremia/inmunología , Viremia/virología , Replicación Viral/efectos de los fármacos , Replicación Viral/inmunología
3.
J Infect Dis ; 229(Supplement_2): S234-S242, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38001044

RESUMEN

BACKGROUND: In the Southeastern United States, the 2022 mpox outbreak disproportionately impacted people who are black and people with HIV (PWH). METHODS: We analyzed a cohort of 395 individuals diagnosed with mpox across 3 health care systems in Atlanta, Georgia between 1 June 2022 and 7 October 2022. We present demographic and clinical characteristics and use multivariable logistic regression analyses to evaluate the association between HIV status and severe mpox (per the US Centers for Disease Control and Prevention definition) and, among PWH, the associations between CD4+ T-cell count and HIV load with severe mpox. RESULTS: Of 395 people diagnosed with mpox, 384 (97.2%) were cisgender men, 335 (84.8%) identified as black, and 324 (82.0%) were PWH. Of 257 PWH with a known HIV load, 90 (35.0%) had > 200 copies/mL. Severe mpox occurred in 77 (19.5%) individuals and there was 1 (0.3%) death. Tecovirimat was prescribed to 112 (28.4%) people, including 56 (72.7%) people with severe mpox. In the multivariable analysis of the total population, PWH had 2.52 times higher odds of severe mpox (95% confidence interval [CI], 1.01-6.27) compared with people without HIV. In the multivariable analysis of PWH, individuals with HIV load > 200 copies/mL had 2.10 (95% CI, 1.00-4.39) times higher odds of severe mpox than PWH who were virologically suppressed. Lower CD4+ T-cell count showed a significant univariate association with severe mpox but was not found to be significantly associated with severe mpox in multivariable analysis. CONCLUSIONS: PWH with nonsuppressed HIV loads had more mpox complications, hospitalizations, and protracted disease courses than people without HIV or PWH with suppressed viral loads. PWH with nonsuppressed HIV loads who are diagnosed with mpox warrant particularly aggressive monitoring and treatment.


Asunto(s)
Infecciones por VIH , Mpox , Estados Unidos , Masculino , Humanos , Benzamidas , Recuento de Linfocito CD4 , Centers for Disease Control and Prevention, U.S.
4.
Clin Infect Dis ; 78(6): 1571-1579, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38279939

RESUMEN

BACKGROUND: Estimated hepatitis C prevalence within the Veterans Health Administration is higher than the general population and is a risk factor for advanced liver disease and subsequent complications. We describe the hepatitis C care continuum within the Veterans Health Administration 1 January 2014 to 31 December 2022. METHODS: We included individuals in Veterans Health Administration care 2021-2022 who were eligible for direct-acting antiviral treatment 1 January 2014 to 31 December 2022. We evaluated the proportion of Veterans who progressed through each step of the hepatitis C care continuum, and identified factors associated with initiating direct-acting antivirals, achieving sustained virologic response, and repeat hepatitis C viremia. RESULTS: We identified 133 732 Veterans with hepatitis C viremia. Hepatitis C treatment was initiated in 107 134 (80.1%), with sustained virologic response achieved in 98 136 (91.6%). In those who achieved sustained virologic response, 1097 (1.1%) had repeat viremia and 579 (52.8%) were retreated for hepatitis C. Veterans of younger ages were less likely to initiate treatment and achieve sustained virologic response, and more likely to have repeat viremia. Stimulant use and unstable housing were negatively associated with each step of the hepatitis C care continuum. CONCLUSIONS: The Veterans Health Administration has treated 80% of Veterans with hepatitis C in care 2021-2022 and achieved sustained virologic response in more than 90% of those treated. Repeat viremia is rare and is associated with younger age, unstable housing, opioid use, and stimulant use. Ongoing efforts are needed to reach younger Veterans, and Veterans with unstable housing or substance use disorders.


Asunto(s)
Antivirales , Continuidad de la Atención al Paciente , Hepatitis C , Respuesta Virológica Sostenida , United States Department of Veterans Affairs , Veteranos , Humanos , Masculino , Estados Unidos/epidemiología , Femenino , Persona de Mediana Edad , Antivirales/uso terapéutico , Veteranos/estadística & datos numéricos , Hepatitis C/tratamiento farmacológico , Hepatitis C/epidemiología , Anciano , Hepacivirus/efectos de los fármacos , Viremia/tratamiento farmacológico , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/epidemiología , Adulto , Salud de los Veteranos
5.
Emerg Infect Dis ; 30(13): S80-S87, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38561831

RESUMEN

Incarcerated persons are infected with hepatitis C virus (HCV) at rates ≈10 times higher than that of the general population in the United States. To achieve national hepatitis C elimination goals, the diagnosis and treatment of hepatitis C in incarcerated persons must be prioritized. In 2022, the Centers for Disease Control and Prevention recommended that all persons receive opt-out HCV screening upon entry into a carceral setting. We review recommendations, treatments, and policy strategies used to promote HCV opt-out universal HCV screening and treatment in incarcerated populations in the United States. Treatment of hepatitis C in carceral settings has increased but varies by jurisdiction and is not sufficient to achieve HCV elimination. Strengthening universal HCV screening and treatment of HCV-infected incarcerated persons is necessary for HCV elimination nationwide.


Asunto(s)
Hepacivirus , Hepatitis C , Humanos , Estados Unidos/epidemiología , Hepacivirus/genética , Antivirales/uso terapéutico , Hepatitis C/diagnóstico , Hepatitis C/tratamiento farmacológico , Hepatitis C/epidemiología , Tamizaje Masivo
6.
PLoS Pathog ; 18(2): e1009831, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35130312

RESUMEN

During chronic human immunodeficiency virus (HIV) or simian immunodeficiency virus (SIV) infection prior to AIDS progression, the vast majority of viral replication is concentrated within B cell follicles of secondary lymphoid tissues. We investigated whether infusion of T cells expressing an SIV-specific chimeric antigen receptor (CAR) and the follicular homing receptor, CXCR5, could successfully kill viral-RNA+ cells in targeted lymphoid follicles in SIV-infected rhesus macaques. In this study, CD4 and CD8 T cells from rhesus macaques were genetically modified to express antiviral CAR and CXCR5 moieties (generating CAR/CXCR5-T cells) and autologously infused into a chronically infected animal. At 2 days post-treatment, the CAR/CXCR5-T cells were located primarily in spleen and lymph nodes both inside and outside of lymphoid follicles. Few CAR/CXCR5-T cells were detected in the ileum, rectum, and lung, and no cells were detected in the bone marrow, liver, or brain. Within follicles, CAR/CXCR5-T cells were found in direct contact with SIV-viral RNA+ cells. We next infused CAR/CXCR5-T cells into ART-suppressed SIV-infected rhesus macaques, in which the animals were released from ART at the time of infusion. These CAR/CXCR5-T cells replicated in vivo within both the extrafollicular and follicular regions of lymph nodes and accumulated within lymphoid follicles. CAR/CXR5-T cell concentrations in follicles peaked during the first week post-infusion but declined to undetectable levels after 2 to 4 weeks. Overall, CAR/CXCR5-T cell-treated animals maintained lower viral loads and follicular viral RNA levels than untreated control animals, and no outstanding adverse reactions were noted. These findings indicate that CAR/CXCR5-T cell treatment is safe and holds promise as a future treatment for the durable remission of HIV.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Receptores CXCR5/inmunología , Receptores Quiméricos de Antígenos/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/terapia , Virus de la Inmunodeficiencia de los Simios/inmunología , Animales , Linfocitos B/inmunología , Centro Germinal/inmunología , Humanos , Inmunoterapia , Ganglios Linfáticos/inmunología , Macaca mulatta , ARN Viral , Receptores CXCR5/metabolismo , Receptores Quiméricos de Antígenos/metabolismo , Carga Viral
7.
J Infect Dis ; 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37739791

RESUMEN

An estimated 2.4 million people in the United States are living with hepatitis C virus (HCV) infection. In 2020, the Centers for Disease Control and Prevention updated hepatitis C screening recommendations to test adults aged ≥ 18 years at least once in a lifetime and pregnant persons during each pregnancy. For those with ongoing exposure to HCV, periodic testing is recommended. The recommended testing sequence is to obtain an HCV antibody test and, when positive, perform an HCV RNA test. Examination of HCV care cascades has found incomplete HCV testing occurs when a separate visit is required to obtain the HCV RNA test. Hepatitis C core antigen (HCVcAg) testing has been shown to be a useful tool for diagnosing current HCV infection is some settings. Hepatitis C testing that is completed, accurate, and efficient is necessary to achieve hepatitis C elimination goals.

8.
Am J Public Health ; 113(2): 162-165, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36480765

RESUMEN

To determine whether the Veterans Health Administration's (VHA) hepatitis C (HCV) treatment campaign reached marginalized populations, we compared HCV care by previous incarceration status with Veterans Aging Cohort Study data. Of those with and those without previous incarceration, respectively, 40% and 21% had detectable HCV, 59% and 65% underwent treatment (P = .07); 92% and 94% of those who completed treatment achieved sustained virologic response. The VHA HCV treatment effort was successful and other systems should replicate those efforts. (Am J Public Health. 2023;113(2):162-165. https://doi.org/10.2105/AJPH.2022.307152).


Asunto(s)
Hepatitis C , Veteranos , Estados Unidos/epidemiología , Humanos , Salud de los Veteranos , Estudios de Cohortes , United States Department of Veterans Affairs , Hepatitis C/tratamiento farmacológico , Hepacivirus , Antivirales/uso terapéutico
9.
MMWR Morb Mortal Wkly Rep ; 72(28): 766-768, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37440452

RESUMEN

Current hepatitis C virus (HCV) testing guidance recommends a two-step testing sequence for diagnosis of HCV infection. Performing an HCV RNA test whenever an HCV antibody test is reactive (complete testing) is critical to achieve national HCV elimination goals. When an HCV antibody test is reactive and no HCV RNA test is performed, testing is considered incomplete. Historically, approximately one third of patients have incomplete testing. This update clarifies that all sites performing HCV screening should ensure single-visit sample collection. This approach allows for automatic HCV RNA testing when an HCV antibody test is reactive to avoid incomplete testing. Use of strategies that require multiple visits to collect HCV testing samples should be discontinued. Automatic HCV RNA testing on all HCV antibody reactive samples will increase the percentage of patients with current HCV infection who are linked to care and receive curative antiviral therapy.


Asunto(s)
Hepacivirus , Hepatitis C , Estados Unidos , Humanos , Hepacivirus/genética , Hepatitis C/diagnóstico , Hepatitis C/prevención & control , Centers for Disease Control and Prevention, U.S. , Tamizaje Masivo , ARN , Anticuerpos contra la Hepatitis C
10.
J Viral Hepat ; 29(12): 1073-1078, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36103593

RESUMEN

Treatment for hepatitis C virus (HCV) with direct-acting antivirals (DAA) is advantageous over previous treatment options due to high efficacy, short treatment duration, and relatively few drug interactions. Similarly, direct oral anticoagulants (DOAC) are generally preferred over warfarin for the management of thrombosis and atrial fibrillation due to a favourable safety profile. Direct-acting antivirals inhibit DOAC transport through P-glycoprotein inhibition leading to a theoretical increase in bleeding risk. We evaluated the incidence of bleeding in patients who received concurrent DAA and DOAC therapy and stratified the analysis based on the patient's cirrhosis status. We conducted a multicenter, retrospective cohort study to evaluate bleeding in patients with HCV and cirrhosis compared to patients with HCV without cirrhosis. Patients receiving at least 1 month of overlapping DAA and DOAC therapy between May 2017 and August 2020 at 11 medical centers in the United Kingdom and three medical centers in the United States were included. Charts were manually reviewed to identify baseline characteristics as well as thromboembolic or bleeding events. Bleeding events were categorized as major bleeding (MB) and clinically relevant non-major bleeding (CRNMB). Of 204 total patients, 36 patients (18%) had cirrhosis and 168 patients (82%) did not have cirrhosis. The majority of patients were male (79%) and Caucasian (75%). Sofosbuvir/velpatasvir (32%) and rivaroxaban (57%) were the most commonly prescribed DAA and DOAC, respectively. Leading indications for anticoagulation included thrombosis (75%) and atrial fibrillation (21%). There were three MB events (1.5%) all of which occurred in patients with additional risk factors (age over 65 and on antiplatelet therapy) and no CRNMB occurred while on DOAC and DAA therapy. Of the three MB, one occurred in a patient with cirrhosis and two in patients without cirrhosis, RR 1.23 (0.56-2.76). In conclusion, in this multicenter cohort study of concurrent DAA and DOAC use, MB was uncommon and there was no CRNMB. There was no significant difference in bleeding events among patients with cirrhosis compared to those without cirrhosis. These findings support the use of DAA among patients requiring DOAC.


Asunto(s)
Fibrilación Atrial , Hepatitis C Crónica , Trombosis , Humanos , Masculino , Femenino , Antivirales/efectos adversos , Hepacivirus , Fibrilación Atrial/inducido químicamente , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/epidemiología , Estudios de Cohortes , Estudios Retrospectivos , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Administración Oral , Anticoagulantes/efectos adversos , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Hemorragia/tratamiento farmacológico , Cirrosis Hepática/tratamiento farmacológico , Trombosis/inducido químicamente , Trombosis/tratamiento farmacológico
11.
PLoS Pathog ; 14(10): e1007350, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30308068

RESUMEN

CD8+ lymphocytes play an important role in suppressing in vivo viral replication in HIV infection. However, both the extent to which and the mechanisms by which CD8+ lymphocytes contribute to viral control are not completely understood. A recent experiment depleted CD8+ lymphocytes in simian immunodeficiency virus (SIV)-infected rhesus macaques (RMs) on antiretroviral treatment (ART) to study the role of CD8+ lymphocytes. CD8+ lymphocytes depletion resulted in temporary plasma viremia in all studied RMs. Viral control was restored when CD8+ lymphocytes repopulated. We developed a viral dynamic model to fit the viral load (VL) data from the CD8 depletion experiment. We explicitly modeled the dynamics of the latent reservoir and the SIV-specific effector cell population including their exhaustion and their potential cytolytic and noncytolytic functions. We found that the latent reservoir significantly contributes to the size of the peak VL after CD8 depletion, while drug efficacy plays a lesser role. Our model suggests that the overall CD8+ lymphocyte cytolytic killing rate is dynamically changing depending on the levels of antigen-induced effector cell activation and exhaustion. Based on estimated parameters, our model suggests that before ART or without ART the overall CD8 cytolytic killing rate is small due to exhaustion. However, after the start of ART, the overall CD8 cytolytic killing rate increases due to an expansion of SIV-specific CD8 effector cells. Further, we estimate that the cytolytic killing rate can be significantly larger than the cytopathic death rate in some animals during the second phase of ART-induced viral decay. Lastly, our model provides a new explanation for the puzzling findings by Klatt et al. and Wong et al. that CD8 depletion done immediately before ART has no noticeable effect on the first phase viral decay slope seen after ART initiation Overall, by incorporating effector cells and their exhaustion, our model can explain the effects of CD8 depletion on VL during ART, reveals a detailed dynamic role of CD8+ lymphocytes in controlling viral infection, and provides a unified explanation for CD8 depletion experimental data.


Asunto(s)
Antirretrovirales/farmacología , Linfocitos T CD8-positivos/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Viremia/veterinaria , Replicación Viral , Animales , Linfocitos T CD8-positivos/efectos de los fármacos , Depleción Linfocítica , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/efectos de los fármacos , Virus de la Inmunodeficiencia de los Simios/crecimiento & desarrollo , Carga Viral , Viremia/inmunología , Viremia/virología
12.
Int J Mol Sci ; 20(20)2019 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-31635220

RESUMEN

The development of in situ major histocompatibility complex (MHC) tetramer (IST) staining to detect antigen (Ag)-specific T cells in tissues has radically revolutionized our knowledge of the local cellular immune response to viral and bacterial infections, cancers, and autoimmunity. IST combined with immunohistochemistry (IHC) enables determination of the location, abundance, and phenotype of T cells, as well as the characterization of Ag-specific T cells in a 3-dimensional space with respect to neighboring cells and specific tissue locations. In this review, we discuss the history of the development of IST combined with IHC. We describe various methods used for IST staining, including direct and indirect IST and IST performed on fresh, lightly fixed, frozen, and fresh then frozen tissue. We also describe current applications for IST in viral and bacterial infections, cancer, and autoimmunity. IST combined with IHC provides a valuable tool for studying and tracking the Ag-specific T cell immune response in tissues.


Asunto(s)
Epítopos de Linfocito T/inmunología , Complejo Mayor de Histocompatibilidad , Multimerización de Proteína , Especificidad del Receptor de Antígeno de Linfocitos T , Linfocitos T/inmunología , Linfocitos T/metabolismo , Humanos , Inmunohistoquímica , Sensibilidad y Especificidad , Coloración y Etiquetado
13.
J Virol ; 90(15): 6699-6708, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27170752

RESUMEN

UNLABELLED: Treatment of human immunodeficiency virus (HIV) infection with antiretroviral therapy (ART) has significantly improved prognosis. Unfortunately, interruption of ART almost invariably results in viral rebound, attributed to a pool of long-lived, latently infected cells. Based on their longevity and proliferative potential, CD4(+) T memory stem cells (TSCM) have been proposed as an important site of HIV persistence. In a previous study, we found that in simian immunodeficiency virus (SIV)-infected rhesus macaques (RM), CD4(+) TSCM are preserved in number but show (i) a decrease in the frequency of CCR5(+) cells, (ii) an expansion of the fraction of proliferating Ki-67(+) cells, and (iii) high levels of SIV DNA. To understand the impact of ART on both CD4(+) TSCM homeostasis and virus persistence, we conducted a longitudinal analysis of these cells in the blood and lymph nodes of 25 SIV-infected RM. We found that ART induced a significant restoration of CD4(+) CCR5(+) TSCM both in blood and in lymph nodes and a reduction in the fraction of proliferating CD4(+) Ki-67(+) TSCM in blood (but not lymph nodes). Importantly, we found that the level of SIV DNA in CD4(+) transitional memory (TTM) and effector memory (TEM) T cells declined ∼100-fold after ART in both blood and lymph nodes, while the level of SIV DNA in CD4(+) TSCM and central memory T cells (TCM-) did not significantly change. These data suggest that ART is effective at partially restoring CD4(+) TSCM homeostasis, and the observed stable level of virus in TSCM supports the hypothesis that these cells are a critical contributor to SIV persistence. IMPORTANCE: Understanding the roles of various CD4(+) T cell memory subsets in immune homeostasis and HIV/SIV persistence during antiretroviral therapy (ART) is critical to effectively treat and cure HIV infection. T memory stem cells (TSCM) are a unique memory T cell subset with enhanced self-renewal capacity and the ability to differentiate into other memory T cell subsets, such as central and transitional memory T cells (TCM and TTM, respectively). CD4(+) TSCM are disrupted but not depleted during pathogenic SIV infection. We find that ART is partially effective at restoring CD4(+) TSCM homeostasis and that SIV DNA harbored within this subset contracts more slowly than virus harbored in shorter-lived subsets, such as TTM and effector memory (TEM). Because of their ability to persist long-term in an individual, understanding the dynamics of virally infected CD4(+) TSCM during suppressive ART is important for future therapeutic interventions aimed at modulating immune activation and purging the HIV reservoir.


Asunto(s)
Antirretrovirales/uso terapéutico , Linfocitos T CD4-Positivos/inmunología , Homeostasis/fisiología , Memoria Inmunológica/inmunología , Enfermedades de los Primates/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Replicación Viral/efectos de los fármacos , Animales , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/virología , ADN Viral/genética , Humanos , Memoria Inmunológica/efectos de los fármacos , Macaca mulatta , Enfermedades de los Primates/inmunología , Enfermedades de los Primates/virología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios , Células Madre/efectos de los fármacos , Células Madre/inmunología , Células Madre/virología , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/virología , Carga Viral
14.
J Virol ; 89(13): 6918-27, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25903334

RESUMEN

UNLABELLED: Human immunodeficiency virus (HIV) in humans and simian immunodeficiency virus (SIV) in macaques (MAC) lead to chronic inflammation and AIDS. Natural hosts, such as African green monkeys (AGM) and sooty mangabeys (SM), are protected against SIV-induced chronic inflammation and AIDS. Here, we report that AGM plasmacytoid dendritic cells (pDC) express extremely low levels of CD4, unlike MAC and human pDC. Despite this, AGM pDC efficiently sensed SIVagm, but not heterologous HIV/SIV isolates, indicating a virus-host adaptation. Moreover, both AGM and SM pDC were found to be, in contrast to MAC pDC, predominantly negative for CCR5. Despite such limited CD4 and CCR5 expression, lymphoid tissue pDC were infected to a degree similar to that seen with CD4(+) T cells in both MAC and AGM. Altogether, our finding of efficient pDC infection by SIV in vivo identifies pDC as a potential viral reservoir in lymphoid tissues. We discovered low expression of CD4 on AGM pDC, which did not preclude efficient sensing of host-adapted viruses. Therefore, pDC infection and efficient sensing are not prerequisites for chronic inflammation. The high level of pDC infection by SIVagm suggests that if CCR5 paucity on immune cells is important for nonpathogenesis of natural hosts, it is possibly not due to its role as a coreceptor. IMPORTANCE: The ability of certain key immune cell subsets to resist infection might contribute to the asymptomatic nature of simian immunodeficiency virus (SIV) infection in its natural hosts, such as African green monkeys (AGM) and sooty mangabeys (SM). This relative resistance to infection has been correlated with reduced expression of CD4 and/or CCR5. We show that plasmacytoid dendritic cells (pDC) of natural hosts display reduced CD4 and/or CCR5 expression, unlike macaque pDC. Surprisingly, this did not protect AGM pDC, as infection levels were similar to those found in MAC pDC. Furthermore, we show that AGM pDC did not consistently produce type I interferon (IFN-I) upon heterologous SIVmac/HIV type 1 (HIV-1) encounter, while they sensed autologous SIVagm isolates. Pseudotyping SIVmac/HIV-1 overcame this deficiency, suggesting that reduced uptake of heterologous viral strains underlays this lack of sensing. The distinct IFN-I responses depending on host species and HIV/SIV isolates reveal the host/virus species specificity of pDC sensing.


Asunto(s)
Células Dendríticas/inmunología , Células Dendríticas/virología , Virus de la Inmunodeficiencia de los Simios/inmunología , Virus de la Inmunodeficiencia de los Simios/fisiología , Internalización del Virus , Animales , Antígenos CD4/análisis , Cercocebus atys , Chlorocebus aethiops , Células Dendríticas/química , Receptores CCR5/análisis
15.
PLoS Pathog ; 10(3): e1003958, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24604066

RESUMEN

Mother-to-infant transmission (MTIT) of HIV is a serious global health concern, with over 300,000 children newly infected in 2011. SIV infection of rhesus macaques (RMs) results in similar rates of MTIT to that of HIV in humans. In contrast, SIV infection of sooty mangabeys (SMs) rarely results in MTIT. The mechanisms underlying protection from MTIT in SMs are unknown. In this study we tested the hypotheses that breast milk factors and/or target cell availability dictate the rate of MTIT in RMs (transmitters) and SMs (non-transmitters). We measured viral loads (cell-free and cell-associated), levels of immune mediators, and the ability to inhibit SIV infection in vitro in milk obtained from lactating RMs and SMs. In addition, we assessed the levels of target cells (CD4+CCR5+ T cells) in gastrointestinal and lymphoid tissues, including those relevant to breastfeeding transmission, as well as peripheral blood from uninfected RM and SM infants. We found that frequently-transmitting RMs did not have higher levels of cell-free or cell-associated viral loads in milk compared to rarely-transmitting SMs. Milk from both RMs and SMs moderately inhibited in vitro SIV infection, and presence of the examined immune mediators in these two species did not readily explain the differential rates of transmission. Importantly, we found that the percentage of CD4+CCR5+ T cells was significantly lower in all tissues in infant SMs as compared to infant RMs despite robust levels of CD4+ T cell proliferation in both species. The difference between the frequently-transmitting RMs and rarely-transmitting SMs was most pronounced in CD4+ memory T cells in the spleen, jejunum, and colon as well as in central and effector memory CD4+ T cells in the peripheral blood. We propose that limited availability of SIV target cells in infant SMs represents a key evolutionary adaptation to reduce the risk of MTIT in SIV-infected SMs.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Cercocebus atys/inmunología , Macaca mulatta/inmunología , Leche/virología , Síndrome de Inmunodeficiencia Adquirida del Simio/transmisión , Animales , Cercocebus atys/virología , Femenino , Lactancia , Macaca mulatta/virología , Embarazo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología
16.
J Immunol ; 192(10): 4666-73, 2014 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-24729621

RESUMEN

Recent studies have identified a subset of memory T cells with stem cell-like properties (T(SCM)) that include increased longevity and proliferative potential. In this study, we examined the dynamics of CD4(+) T(SCM) during pathogenic SIV infection of rhesus macaques (RM) and nonpathogenic SIV infection of sooty mangabeys (SM). Whereas SIV-infected RM show selective numeric preservation of CD4(+) T(SCM), SIV infection induced a complex perturbation of these cells defined by depletion of CD4(+)CCR5(+) T(SCM), increased rates of CD4(+) T(SCM) proliferation, and high levels of direct virus infection. The increased rates of CD4(+) T(SCM) proliferation in SIV-infected RM correlated inversely with the levels of central memory CD4(+) T cells. In contrast, nonpathogenic SIV infection of SM evidenced preservation of both CD4(+) T(SCM) and CD4(+) central memory T cells, with normal levels of CD4(+) T(SCM) proliferation, and lack of selective depletion of CD4(+)CCR5(+) T(SCM). Importantly, SIV DNA was below the detectable limit in CD4(+) T(SCM) from 8 of 10 SIV-infected SM. We propose that increased proliferation and infection of CD4(+) T(SCM) may contribute to the pathogenesis of SIV infection in RM.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Memoria Inmunológica , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Animales , Linfocitos T CD4-Positivos/patología , Cercocebus atys , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio/patología , Factores de Tiempo
17.
Clin Infect Dis ; 61(8): 1304-6, 2015 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-26082511

RESUMEN

Treatment of hepatitis C virus with potent, interferon-free, direct-acting antiviral regimens with no activity against hepatitis B virus (HBV) may increase the risk for HBV reactivation in coinfected patients. We present 2 cases of HBV reactivation during treatment with an all-oral regimen of simeprevir and sofosbuvir and discuss strategies to prevent HBV flare.


Asunto(s)
Antivirales/uso terapéutico , Coinfección , Virus de la Hepatitis B/fisiología , Hepatitis B/complicaciones , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Simeprevir/uso terapéutico , Sofosbuvir/uso terapéutico , Administración Oral , Antivirales/administración & dosificación , Quimioterapia Combinada , Hepatitis B/virología , Hepatitis C Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Simeprevir/administración & dosificación , Sofosbuvir/administración & dosificación
18.
Public Health Rep ; 139(1): 94-101, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37924253

RESUMEN

OBJECTIVE: Inpatient vaccination is an opportunity to increase vaccine uptake among patients at high risk for severe COVID-19 illness. We designed and implemented a hospital-based COVID-19 vaccination program with the aim of increasing documentation of vaccine eligibility and COVID-19 vaccination to eligible inpatients before discharge. METHODS: We integrated a templated note into the electronic medical records and trained health care personnel to screen inpatients and document COVID-19 vaccine eligibility at the Atlanta Veterans Affairs Medical Center. Vaccination staff deployed to inpatient wards administered the vaccine to eligible and consenting patients at the bedside. We calculated the number of inpatients whose vaccine eligibility was assessed and documented during a 4-week period after health care personnel were trained. We used the Wald χ2 test to compare the proportion of eligible patients who were vaccinated before discharge 4 weeks before (March 29-April 23, 2021) and 4 weeks after (May 3-28, 2021) the training period. RESULTS: During the 4 weeks before the training period, COVID-19 vaccine eligibility was not routinely assessed and documented. Of 793 inpatients discharged during the 4 weeks after the training period, 470 (59%) had COVID-19 vaccine eligibility documented. Of 86 patients who were eligible for vaccination, 61 (71%) received COVID-19 vaccination before discharge. COVID-19 vaccination rates during hospitalization increased significantly from 16 of 769 inpatients (2%) during the 4 weeks before training to 61 of 793 inpatients (8%) during the 4 weeks after training (P < .001). CONCLUSION: An inpatient vaccination program that integrated COVID-19 vaccination into discharge planning increased vaccine screening and uptake. Future studies are needed to identify barriers to vaccination and strategies to increase vaccine uptake among those who are hesitant.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Veteranos , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19/administración & dosificación , Georgia , Hospitales , Pacientes Internos , Vacunación/estadística & datos numéricos
19.
J Womens Health (Larchmt) ; 33(6): 695-701, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38476092

RESUMEN

New U.S. Centers for Disease Control and Prevention (CDC) guidelines for hepatitis C virus (HCV) testing of perinatally exposed infants and children released in 2023 recommend a nucleic acid test (NAT) for detection of HCV ribonucleic acid (i.e., NAT for HCV RNA) at 2-6 months of age to facilitate early identification and linkage to care for children with perinatally acquired HCV infection. Untreated hepatitis C can lead to cirrhosis, liver cancer, and premature death and is caused by HCV, a blood-borne virus transmitted most often among adults through injection drug use in the United States. Perinatal exposure from a birth parent with HCV infection is the most frequent mode of HCV transmission among infants and children. New HCV infections have been increasing since 2010, with the highest rates of infection among people aged 20-39 years, leading to an increasing prevalence of HCV infection during pregnancy. In 2020, the CDC recommended one-time HCV screening for all adults aged 18 years and older and for all pregnant persons during each pregnancy. Detecting HCV infection during pregnancy is key for the identification of pregnant persons, linkage to care for postpartum treatment, and identification of infants with perinatal exposure for HCV testing. It was previously recommended that children who were exposed to HCV during pregnancy receive an antibody to HCV (anti-HCV) test at 18 months of age; however, most children were lost to follow-up before testing occurred, leaving children with perinatal infection undiagnosed. The new strategy of testing perinatally exposed children at age 2-6 months was found to be cost-effective in increasing the identification of infants who might develop chronic hepatitis C. This report describes the current perinatal HCV testing recommendations and how they advance national hepatitis C elimination efforts by improving the health of pregnant and postpartum people and their children.


Asunto(s)
Centers for Disease Control and Prevention, U.S. , Hepacivirus , Hepatitis C , Transmisión Vertical de Enfermedad Infecciosa , Tamizaje Masivo , Complicaciones Infecciosas del Embarazo , Humanos , Estados Unidos/epidemiología , Femenino , Hepatitis C/diagnóstico , Hepatitis C/transmisión , Hepatitis C/prevención & control , Embarazo , Lactante , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/prevención & control , Hepacivirus/aislamiento & purificación , Hepacivirus/genética , Niño , Tamizaje Masivo/métodos , Recién Nacido , Adulto , Guías de Práctica Clínica como Asunto , Preescolar
20.
PLoS One ; 19(7): e0306224, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39052561

RESUMEN

The development and use of virtual laboratories to augment traditional in-person skills training continues to grow. Virtual labs have been implemented in a number of diverse educational settings, which have many purported benefits including their adaptability, accessibility, and repeatability. However, few studies have evaluated the impact of virtual laboratories outside of academic achievement and skills competencies, especially in biotechnology. In this study, an interdisciplinary team of content experts, video game researchers, instructional designers, and assessment experts developed a 3D immersive simulation designed to teach novice scientists the technical skills necessary to perform sterile mammalian cell culture technique. Unique to the simulation development process is the recreation of an immersive experience through the capture of details in the real-world lab where participants have the freedom of choice in their actions, while receiving immediate feedback on their technical skills as well as procedural execution. However, unlike an in-person laboratory course, students are able to iterate and practice their skills outside of class time and learn from their mistakes. Over the course of two semesters, we used a mixed-methods study design to evaluate student attitudes towards the simulation and their science motivational beliefs. Students' self-efficacy and science identity were assessed after engaging with the simulation prior to the physical laboratory. Our results show that students' science identity remained unchanged while their science self-efficacy increased. Furthermore, students had positive perceptions of the benefits of the virtual simulation. These data suggest that the virtual cell culture simulation can be a useful pedagogical training tool to support students' motivational beliefs that is both accessible and easy to implement.


Asunto(s)
Biotecnología , Motivación , Estudiantes , Humanos , Estudiantes/psicología , Biotecnología/educación , Biotecnología/métodos , Masculino , Femenino , Realidad Virtual , Adulto Joven , Adulto , Simulación por Computador
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