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1.
Mol Cell ; 78(6): 1207-1223.e8, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32504554

RESUMO

Tumor interferon (IFN) signaling promotes PD-L1 expression to suppress T cell-mediated immunosurveillance. We identify the IFN-stimulated non-coding RNA 1 (INCR1) as a long noncoding RNA (lncRNA) transcribed from the PD-L1 locus and show that INCR1 controls IFNγ signaling in multiple tumor types. Silencing INCR1 decreases the expression of PD-L1, JAK2, and several other IFNγ-stimulated genes. INCR1 knockdown sensitizes tumor cells to cytotoxic T cell-mediated killing, improving CAR T cell therapy. We discover that PD-L1 and JAK2 transcripts are negatively regulated by binding to HNRNPH1, a nuclear ribonucleoprotein. The primary transcript of INCR1 binds HNRNPH1 to block its inhibitory effects on the neighboring genes PD-L1 and JAK2, enabling their expression. These findings introduce a mechanism of tumor IFNγ signaling regulation mediated by the lncRNA INCR1 and suggest a therapeutic target for cancer immunotherapy.


Assuntos
Antígeno B7-H1/genética , Interferon gama/metabolismo , RNA Longo não Codificante/genética , Idoso , Animais , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imunoterapia , Imunoterapia Adotiva/métodos , Interferon gama/genética , Interferons/genética , Interferons/metabolismo , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD , Pessoa de Meia-Idade , Proteína 2 Ligante de Morte Celular Programada 1/genética , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linfócitos T Citotóxicos
2.
Clin Gastroenterol Hepatol ; 21(3): 761-770.e13, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36075499

RESUMO

BACKGROUND & AIMS: Population-based studies have suggested an increased risk of acute arterial events (AAEs) in patients with inflammatory bowel disease (IBD). We aimed to assess the risk of incident AAEs and premature AAEs, adjusted for diet, physical activity, and inflammation biomarkers, in participants with IBD in the UK Biobank (UKB) METHODS: UKB participants with IBD and without prevalent AAEs at enrollment were matched to random non-IBD controls. A Cox regression model, adjusting for baseline cardiovascular and IBD risk factors, diet, physical activity, and high-sensitivity C-reactive protein, estimated adjusted hazard ratios (aHRs) for association between IBD and AAEs or premature AAEs (age, <55 years for men and <65 years for women). Predictors of AAEs within the IBD cohort were identified in a Cox model adjusting for disease severity (IBD-related hospitalizations or surgeries). RESULTS: Among 455,950 UKB participants, 5094 with IBD were matched to 20,376 non-IBD controls. After a median follow-up period of 12.4 years, participants with IBD had a higher incident rate of AAE (924.1 vs 730.9 per 100,000 person years; P < .001), risk of all AAEs (aHR, 1.19; 95% CI, 1.08-1.31; P < .001), and premature AAEs (aHR, 1.38; 95% CI, 1.11-1.72; P = .001). High-sensitivity C-reactive protein levels (highest quartile: aHR, 1.53; 95% CI, 1.15-2.03) and disease severity (aHR, 5.40; 95% CI, 4.03-7.22) were independent predictors of AAE in IBD. CONCLUSIONS: In a prospective cohort, there was an increased risk of incident AAEs and premature AAEs in IBD participants. Beyond traditional AAE risk factors, quantifiable indices of IBD disease activity and severity were independent predictors of AAEs.


Assuntos
Proteína C-Reativa , Doenças Inflamatórias Intestinais , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estudos Prospectivos , Bancos de Espécimes Biológicos , Doenças Inflamatórias Intestinais/complicações , Fatores de Risco , Reino Unido
3.
J Clin Gastroenterol ; 57(7): 707-713, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36730876

RESUMO

GOALS: Examine outcomes among homeless patients admitted with gastrointestinal (GI) bleeding, including all-cause mortality and endoscopic intervention rates. BACKGROUND: Hospitalizations among homeless individuals have increased steadily since at least 2007 but little is known about GI outcomes in these patients. STUDY: The 2010-2014 Healthcare Utilization Project (HCUP) State Inpatient Databases from New York and Florida were used to identify adults admitted with a primary diagnosis of acute upper or lower GI bleed. Homeless patients were 1:3 matched with nonhomeless patients using a propensity-score greedy-matched algorithm. The primary outcome (all-cause in-hospital mortality) and secondary outcomes (30-day readmission rates, endoscopy utilization, length of stay, and total hospitalization costs) were compared. RESULTS: We matched 4074 homeless patients with 12,222 nonhomeless patients. Most hospitalizations for homeless individuals were concentrated in 113 (26.4%) of 428 hospitals. Homeless adults were more likely to be younger, male, African American or Hispanic, and on Medicaid. They experienced significantly higher odds of all-cause inpatient mortality compared with nonhomeless patients admitted with GI bleeding (OR 1.37, 95% CI 1.11-1.69). Endoscopy utilization rates were also lower for both upper (OR 0.62, 95% CI 0.55-0.71) and lower (OR 0.76, 95% CI 0.68-0.85) GI bleeding, though upper endoscopy rates within the first 24 hours were comparable (OR 1.11, 95% CI 1.00-1.23). Total hospitalization costs were lower ($9,715 vs. $12,173, P <0.001) while 30-day all-cause readmission rates were significantly higher in the homeless group (14.9% vs. 18.4%, P <0.001). CONCLUSIONS: Homeless patients hospitalized for GI bleeding face disparities, including higher mortality rates and lower endoscopy utilization.


Assuntos
Disparidades em Assistência à Saúde , Pessoas Mal Alojadas , Adulto , Estados Unidos , Humanos , Masculino , Hospitalização , Readmissão do Paciente , Hemorragia Gastrointestinal/epidemiologia , Hemorragia Gastrointestinal/terapia , Hemorragia Gastrointestinal/etiologia , Estudos Retrospectivos , Tempo de Internação
4.
J Clin Gastroenterol ; 56(7): 576-583, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34319947

RESUMO

GOALS: The aim was to investigate the impact of night-time emergency department (ED) presentation on outcomes of patients admitted for acute upper gastrointestinal hemorrhage (UGIH). BACKGROUND: The relationship between time of ED presentation and outcomes of gastrointestinal hemorrhage is unclear. STUDY: Using the 2016 and 2017 Florida State Inpatient Databases which provide times of ED arrival, we identified and categorized adults hospitalized for UGIH to daytime (07:00 to 18:59 h) and night-time (19:00 to 06:59 h) based on the time of ED presentation. We matched both groups with propensity scores, and assessed their clinical outcomes including all-cause in-hospital mortality, in-hospital endoscopy utilization, length of stay (LOS), total hospitalization costs, and 30-day all-cause readmission rates. RESULTS: Of the identified 38,114 patients with UGIH, 89.4% (n=34,068) had acute nonvariceal hemorrhage (ANVH), while 10.6% (n=4046) had acute variceal hemorrhage (AVH). Compared with daytime patients, ANVH patients admitted at night-time had higher odds of in-hospital mortality (odds ratio: 1.32; 95% confidence interval: 1.06-1.60), lower odds of in-patient endoscopy (odds ratio: 0.83; 95% confidence interval: 0.77-0.90), higher total hospital costs ($9911 vs. $9545, P <0.016), but similar LOS and readmission rates. Night-time AVH patients had a shorter LOS (5.4 vs. 5.8 d, P =0.045) but similar mortality rates, endoscopic utilization, total hospitalization costs, and readmission rates as daytime patients. CONCLUSIONS: Patients arriving in the ED at night-time with ANVH had worse outcomes (mortality, hospitalization costs, and endoscopy utilization) compared with daytime patients. However, those with AVH had comparable outcomes irrespective of ED arrival time.


Assuntos
Serviço Hospitalar de Emergência , Varizes Esofágicas e Gástricas , Hemorragia Gastrointestinal/terapia , Adulto , Serviço Hospitalar de Emergência/economia , Endoscopia Gastrointestinal/estatística & dados numéricos , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/terapia , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologia , Mortalidade Hospitalar , Humanos , Tempo de Internação , Readmissão do Paciente/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
5.
Clin Gastroenterol Hepatol ; 19(10): 2207-2209.e3, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33068786

RESUMO

The safety and efficacy of tofacitinib in Crohn's disease (CD) has been studied in 2 phase II trials in patients with moderate-to-severe CD with no new safety signals observed, but no significant difference from placebo in the primary efficacy endpoint of clinical response.1-3 However, post hoc analyses and smaller studies have observed clinical and biologic response to tofacitinib in patients with CD.2,4,5 There is a paucity of real-world effectiveness and safety data for tofacitinib in non-Food and Drug Administration label usage in patients with CD and patients with inflammatory bowel disease-unclassified (IBD-U).


Assuntos
Doença de Crohn , Doenças Inflamatórias Intestinais , Doença de Crohn/tratamento farmacológico , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Piperidinas , Pirimidinas/efeitos adversos , Pirróis/efeitos adversos
6.
Clin Gastroenterol Hepatol ; 19(8): 1592-1601.e3, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32629130

RESUMO

BACKGROUND & AIMS: Adverse events (AEs) including reactivation of herpes zoster (HZ) and venous thromboembolism (VTE) have been reported from clinical trials of tofacitinib in ulcerative colitis (UC). We investigated the incidence rates of AEs in a real-world study of UC patients given tofacitinib. METHODS: We collected data from 260 patients with UC in the Tofacitinib Real-world Outcomes in Patients with ulceratIve colitis and Crohn's disease consortium study, performed at 6 medical centers in the United States. Patients were followed up for a median of 6 months (interquartile range, 2.7-11.5 mo). AEs were captured using a standardized data collection instrument before study initiation and at weeks 8, 16, 26, 39, and 52. Serious AEs were defined as life-threatening or resulting in a hospitalization, disability, or discontinuation of therapy. Logistic regression was performed to examine risk factors for AEs. RESULTS: AEs occurred in 41 patients (15.7%); most were infections (N = 13; 5.0%). The incidence rate of any AE was 27.2 (95% CI, 24.4-30.7 per 100 patient-years of follow-up evaluation). Fifteen were serious AEs (36.6% of AEs), and tofacitinib was discontinued for 12 patients (4.6% of cohort). The incidence rates of serious AEs was 10.0 (95% CI, 8.9-11.2 per 100 patient-years of follow-up evaluation). Five patients developed HZ infection and 2 developed VTE (all receiving 10 mg tofacitinib, twice per day). CONCLUSIONS: Real-world safety signals for tofacitinib are similar to those for clinical trials, with AEs reported from almost 16% of patients. HZ infection and VTE occurred in patients receiving 10 mg tofacitinib twice per day. These results support dose de-escalation after induction therapy, to reduce the risk of AEs.


Assuntos
Colite Ulcerativa , Colite Ulcerativa/tratamento farmacológico , Humanos , Piperidinas/efeitos adversos , Pirimidinas/efeitos adversos , Pirróis/efeitos adversos
7.
Clin Gastroenterol Hepatol ; 21(7): 1970-1971, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36379400
8.
Endoscopy ; 48(12): 1059-1068, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27617421

RESUMO

Background and study aim: Peroral endoscopic myotomy (POEM) is a relatively novel minimally invasive technique that is used to treat achalasia and other esophageal motility disorders. We systematically reviewed the medical literature in order to evaluate the safety and efficacy of POEM. Methods: We performed a comprehensive review and meta-analysis of studies published up to March 2016 that reported on clinical outcomes of POEM. Five databases were searched: MEDLINE, EMBASE, Ovid, CINAHL, and Cochrane. Results: A total of 36 studies involving 2373 patients were included in the review. Clinical success (Eckardt score ≤ 3) was achieved in 98 % (95 % confidence interval [CI] 97 % - 100 %) of patients after the procedure. The mean Eckardt score decreased from 6.9 ±â€Š0.15 preoperatively to 0.77 ±â€Š0.10, 1.0 ±â€Š0.10, and 1.0 ±â€Š0.08 within 1, 6, and 12 months of treatment. In addition, there were significant decreases in the average lower esophageal sphincter pressure, integrated relaxation pressure, and the average heights of the barium column following a timed barium esophagogram after the procedure. After a mean follow-up of 8 months post-procedure, the rates of symptomatic gastroesophageal reflux, esophagitis on esophagogastroduodenoscopy, and abnormal acid exposure were 8.5 % (95 %CI 4.9 % - 13 %), 13 % (95 %CI 5.0 % - 23 %), and 47 % (95 %CI 21 % - 74 %), respectively. Conclusions: POEM appears to be safe and effective based on the large body of current evidence, and warrants consideration as first-line therapy when an expert operator is available.


Assuntos
Acalasia Esofágica/cirurgia , Esfíncter Esofágico Inferior/cirurgia , Cirurgia Endoscópica por Orifício Natural/métodos , Acalasia Esofágica/fisiopatologia , Esfíncter Esofágico Inferior/fisiopatologia , Esofagite/etiologia , Refluxo Gastroesofágico/etiologia , Humanos , Cirurgia Endoscópica por Orifício Natural/efeitos adversos , Índice de Gravidade de Doença
9.
Oncoimmunology ; 13(1): 2348254, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737793

RESUMO

Metastatic (m) colorectal cancer (CRC) is an incurable disease with a poor prognosis and thus remains an unmet clinical need. Immune checkpoint blockade (ICB)-based immunotherapy is effective for mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) mCRC patients, but it does not benefit the majority of mCRC patients. NK cells are innate lymphoid cells with potent effector responses against a variety of tumor cells but are frequently dysfunctional in cancer patients. Memory-like (ML) NK cells differentiated after IL-12/IL-15/IL-18 activation overcome many challenges to effective NK cell anti-tumor responses, exhibiting enhanced recognition, function, and in vivo persistence. We hypothesized that ML differentiation enhances the NK cell responses to CRC. Compared to conventional (c) NK cells, ML NK cells displayed increased IFN-γ production against both CRC cell lines and primary patient-derived CRC spheroids. ML NK cells also exhibited improved killing of CRC target cells in vitro in short-term and sustained cytotoxicity assays, as well as in vivo in NSG mice. Mechanistically, enhanced ML NK cell responses were dependent on the activating receptor NKG2D as its blockade significantly decreased ML NK cell functions. Compared to cNK cells, ML NK cells exhibited greater antibody-dependent cytotoxicity when targeted against CRC by cetuximab. ML NK cells from healthy donors and mCRC patients exhibited increased anti-CRC responses. Collectively, our findings demonstrate that ML NK cells exhibit enhanced responses against CRC targets, warranting further investigation in clinical trials for mCRC patients, including those who have failed ICB.


Assuntos
Diferenciação Celular , Neoplasias Colorretais , Memória Imunológica , Células Matadoras Naturais , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/tratamento farmacológico , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Humanos , Animais , Camundongos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Interferon gama/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Camundongos Endogâmicos NOD , Feminino
10.
Crohns Colitis 360 ; 4(1): otac002, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35310082

RESUMO

Background: Combining biologics and small molecules could potentially overcome the plateau of drug efficacy in inflammatory bowel disease (IBD). We conducted a systematic review and meta-analysis to assess the safety and effectiveness of dual biologic therapy (DBT), or small molecule combined with a biologic therapy (SBT) in IBD patients. Methods: We searched MEDLINE, EMBASE, Scopus, Web of Science, Cochrane Database of Systematic Reviews, and Clinical trials.gov until November 3, 2020, including studies with 2 or more IBD patients on DBT or SBT. Main outcome was safety assessed as pooled rates of adverse events (AEs) and serious AEs (SAEs) for each combination. Effectiveness was reported as pooled rates of clinical, endoscopic, and/or radiographic response and remission. The certainty of evidence was rated according to the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) framework. Results: Of the 3688 publications identified, 13 studies (1 clinical trial, 12 observational studies) involving 266 patients on 7 different combinations were included. Median number of prior biologics ranged from 0 to 4, and median duration of follow-up was 16-68 weeks. Most common DBT and SBT were vedolizumab (VDZ) with anti-tumor necrosis factor (aTNF, n = 56) or tofacitinib (Tofa, n = 57), respectively. Pooled rates of SAE for these were 9.6% (95% confidence interval [CI], 1.5-21.4) for VDZ-aTNF and 1.0% (95% CI, 0.0-7.6) for Tofa-VDZ. The overall certainty of evidence was very low due to the observational nature of the studies, and very serious imprecision and inconsistency. Conclusions: DBT or SBT appears to be generally safe and may be effective in IBD patients, but the evidence is very uncertain.

11.
Oxf Med Case Reports ; 2021(3): omaa148, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33732477

RESUMO

A 55-year-old male presented to the emergency department with the complaints of chest pain that started 4 h before presentation. Pain was located over the anterior chest, 5 out of 10 intensity, with radiation to the left arm. Chest x-ray on admission showed severe diffuse bilateral pulmonary infiltrates concerning for COVID-19 pneumonia. Electrocardiogram showed inferior and lateral ST-segment elevation compatible with acute inferolateral myocardial infarction. Successful percutaneous coronary intervention (PCI) of the proximal and mid-right coronary artery using the balloon angioplasty and drug-eluting stent was performed. Post-PCI stenosis was 0% with a thrombolysis in myocardial infarction (TIMI) flow of 3. Five-day course of azithromycin and hydroxychloroquine was completed with no improvement overall. Patient received two doses of 400 mg of tocilizumab intravenously on hospital days 5 (HD#5) and #6. The patient was proned, on FiO2 100%, PEEP 15 cm H2O, on epoprostenol sodium and paralytics and eventually received venovenous ECMO, which improved outcome.

12.
Sci Rep ; 10(1): 5095, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32198420

RESUMO

The mode of action for oncolytic viruses (OVs) in cancer treatment is thought to depend on a direct initial cytotoxic effect against infected tumor cells and subsequent activation of immune cell responses directed against the neoplasm. To study both of these effects in a mouse model of glioblastoma (GBM), we employed murine GBM cells engineered to constitutively express the type I Herpes Simplex Virus (HSV1) HSV-1 receptor, nectin-1, to allow for more efficient infection and replication by oncolytic HSV (oHSV). These cells were further engineered with a surrogate tumor antigen to facilitate assays of T cell activity. We utilized MRI-based volumetrics to measure GBM responses after injection with the oHSV and bioluminescent imaging (BLI) to determine oHSV replicative kinetics in the injected tumor mass. We found increased infiltration of both surrogate tumor antigen- and oHSV antigen-specific CD8+ T cells within 7 days after oHSV injection. There was no increase in tumor infiltrating CD8+ T cells expressing "exhaustion" markers, yet oHSV infection led to a reduction in PD-1+ CD8+ T cells in injected GBMs and an increase in IFNγ+ CD8+ T cells. There was a significant direct correlation between oHSV-mediated reduction in GBM volume and increased infiltration of both viral and tumor antigen-specific CD8+ T cells, as well as oHSV intratumoral gene activity. These findings imply that CD8+ T cell cytotoxicity against both tumor and viral antigens as well as intratumoral oHSV gene expression are important in oHSV-mediated GBM therapy.


Assuntos
Antígenos de Neoplasias/imunologia , Antígenos Virais/imunologia , Neoplasias Encefálicas/imunologia , Glioblastoma/imunologia , Terapia Viral Oncolítica/métodos , Linfócitos T Citotóxicos/imunologia , Animais , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Glioblastoma/patologia , Glioblastoma/terapia , Herpesvirus Humano 1/imunologia , Humanos , Interferon gama/imunologia , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Vírus Oncolíticos , Receptores Virais/genética , Receptores Virais/imunologia
14.
Inflamm Bowel Dis ; 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38241516

RESUMO

This study suggests that the current atherosclerotic cardiovascular disease risk prediction models used in clinical practice performed better in the non­inflammatory bowel disease (IBD) cohort compared with IBD, highlighting the need for a more specific risk prediction model tailored to the IBD population.

15.
Sci Rep ; 8(1): 208, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29317703

RESUMO

T cell exhaustion occurs during chronic infection and cancers. Programmed cell death protein-1 (PD-1) is a major inhibitory checkpoint receptor involved in T cell exhaustion. Blocking antibodies (Abs) against PD-1 or its ligand, PD-L1, have been shown to reverse T cell exhaustion during chronic infection and cancers, leading to improved control of persistent antigen. However, modeling tumor-specific T cell responses in mouse has been difficult due to the lack of reagents to detect and phenotype tumor-specific immune responses. We developed a novel mouse glioma model expressing a viral epitope derived from lymphocytic choriomeningitis virus (LCMV), which allowed monitoring of tumor-specific CD8 T-cell responses. These CD8 T cells express high levels of PD-1 and are unable to reject tumors, but this can be reversed by anti-PD-1 treatment. These results suggest the efficacy of PD-1 blockade as a treatment for glioblastoma, an aggressive tumor that results in a uniformly lethal outcome. Importantly, this new syngeneic tumor model may also provide further opportunities to characterize anti-tumor T cell exhaustion and develop novel cancer immunotherapies.


Assuntos
Neoplasias Encefálicas/imunologia , Linfócitos T CD8-Positivos/imunologia , Glioblastoma/imunologia , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Epitopos/imunologia , Vírus da Coriomeningite Linfocítica/genética , Vírus da Coriomeningite Linfocítica/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo
16.
mSphere ; 2(6)2017.
Artigo em Inglês | MEDLINE | ID: mdl-29242831

RESUMO

The unprecedented challenges of developing effective vaccines against intracellular pathogens such as HIV, malaria, and tuberculosis have resulted in more rational approaches to vaccine development. Apart from the recent advances in the design and selection of improved epitopes and adjuvants, there are also ongoing efforts to optimize delivery platforms. Viral vectors are the best-characterized delivery tools because of their intrinsic adjuvant capability, unique cellular tropism, and ability to trigger robust adaptive immune responses. However, a known limitation of viral vectors is preexisting immunity, and ongoing efforts are aimed at developing novel vector platforms with lower seroprevalence. It is also becoming increasingly clear that different vectors, even those derived from phylogenetically similar viruses, can elicit substantially distinct immune responses, in terms of quantity, quality, and location, which can ultimately affect immune protection. This review provides a summary of the status of viral vector development for HIV vaccines, with a particular focus on novel viral vectors and the types of adaptive immune responses that they induce.

17.
Vaccine ; 35(1): 1-9, 2017 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-27899229

RESUMO

An important focus in vaccine research is the design of vaccine vectors with low seroprevalence and high immunogenicity. Replication-incompetent lymphocytic choriomeningitis virus (rLCMV) vectors do not elicit vector-neutralizing antibody responses, and homologous prime-boost regimens with rLCMV vectors induce boostable and protective T cell responses to model antigens in mice. However, cellular and humoral immune responses following homologous rLCMV vaccine regimens have not been rigorously evaluated in non-human primates (NHPs). To test whether rLCMV vectors constitute an effective vaccine platform in NHPs, we developed rLCMV vectors expressing SIVmac239 Env and Gag antigens and assessed their immunogenicity in mice and cynomolgus macaques. Immunization with rLCMV vaccine vectors expressing SIV Env and Gag was effective at generating SIV-specific T cell and antibody responses in both mice and NHPs. Epitope mapping using SIV Env in C57BL/6 mice demonstrated that rLCMV vectors induced sustained poly-functional responses to both dominant and subdominant epitopes. Our results suggest the potential of rLCMV vectors as vaccine candidates. Future SIV challenge experiments in rhesus macaques will be needed to assess immune protection by these vaccine vectors.


Assuntos
Antígenos Virais/imunologia , Portadores de Fármacos , Vírus da Coriomeningite Linfocítica/genética , Vacinas contra a SAIDS/imunologia , Vírus da Imunodeficiência Símia/imunologia , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/genética , Macaca fascicularis , Camundongos Endogâmicos C57BL , Vacinas contra a SAIDS/administração & dosagem , Vacinas contra a SAIDS/genética , Vírus da Imunodeficiência Símia/genética , Linfócitos T/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
19.
Vaccine ; 34(41): 4955-4963, 2016 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-27566899

RESUMO

T cells are an important component of immune responses, and their function is influenced by their expression of inhibitory receptors. Immunization with alternative serotype adenovirus (Ad) vectors induces highly functional T cell responses with lower programmed cell death 1 (PD-1) expression and increased boostability relative to Ad5 vectors. However, a detailed phenotypic characterization of other inhibitory receptors is lacking, and it is unknown whether Ad5-induced CD8 T cells eventually recover function with time. In this report, we measure the expression of various inhibitory receptors and memory markers during early and late time points following vaccination with Ad5 and alternative serotype Ad vectors. CD8 T cells induced by Ad5 exhibited increased expression of the inhibitory receptor Tim-3 and showed decreased central memory differentiation as compared with alternative serotype Ad vectors, even a year following immunization. Moreover, relative to Ad5-primed mice, Ad26-primed mice exhibited substantially improved recall of SIV Gag-specific CD8 T cell responses following heterologous boosting with MVA or Ad35 vectors. We also demonstrate that low doses of Ad5 priming resulted in more boostable immune responses with lower PD-1 expression as compared to high Ad5 doses, suggesting a role for vector dose in influencing immune dysfunction following Ad5 vaccination. These data suggest that Ad5 vectors induce a long-term pattern of immune exhaustion that can be partly overcome by lowering vector dose and modulating inhibitory signals.


Assuntos
Adenoviridae , Linfócitos T CD8-Positivos/imunologia , Vetores Genéticos , Memória Imunológica , Animais , Citocinas/imunologia , Feminino , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Imunização , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1/metabolismo
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