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1.
NPJ Vaccines ; 9(1): 74, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582771

RESUMO

Recombinant native-like HIV-1 envelope glycoprotein (Env) trimers are used in candidate vaccines aimed at inducing broadly neutralizing antibodies. While state-of-the-art SOSIP or single-chain Env designs can be expressed as native-like trimers, undesired monomers, dimers and malformed trimers that elicit non-neutralizing antibodies are also formed, implying that these designs could benefit from further modifications for gene-based vaccination approaches. Here, we describe the triple tandem trimer (TTT) design, in which three Env protomers are genetically linked in a single open reading frame and express as native-like trimers. Viral vectored Env TTT induced similar neutralization titers but with a higher proportion of trimer-specific responses. The TTT design was also applied to generate influenza hemagglutinin (HA) trimers without the need for trimerization domains. Additionally, we used TTT to generate well-folded chimeric Env and HA trimers that harbor protomers from three different strains. In summary, the TTT design is a useful platform for the design of HIV-1 Env and influenza HA immunogens for a multitude of vaccination strategies.

3.
Front Immunol ; 14: 1186478, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37529048

RESUMO

Introduction: The primary goal of this work is to broaden and enhance the options for induction of protective CD8+ T cells against HIV-1 and respiratory pathogens. Methods: We explored the advantages of the parainfluenza virus 5 (PIV5) vector for delivery of pathogen-derived transgenes alone and in combination with the in-human potent regimen of simian adenovirus ChAdOx1 prime-poxvirus MVA boost delivering bi-valent mosaic of HIV-1 conserved regions designated HIVconsvX. Results: We showed in BALB/c mice that the PIV5 vector expressing the HIVconsvX immunogens could be readily incorporated with the other two vaccine modalities into a single regimen and that for specific vector combinations, mucosal CD8+ T-cell induction was enhanced synergistically by a combination of the intranasal and intramuscular routes of administration. Discussion: Encouraging safety and immunogenicity data from phase 1 human trials of ChAdOx1- and MVA-vectored vaccines for HIV-1, and PIV5-vectored vaccines for SARS-CoV-2 and respiratory syncytial virus pave the way for combining these vectors for HIV-1 and other indications in humans.


Assuntos
Adenovirus dos Símios , COVID-19 , HIV-1 , Vírus Sincicial Respiratório Humano , Camundongos , Animais , Humanos , Adenovirus dos Símios/genética , Linfócitos T CD8-Positivos , Vacinas contra COVID-19 , SARS-CoV-2
4.
Vaccines (Basel) ; 11(7)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37515003

RESUMO

We develop candidate HIV-1 vaccines, of which two components, ChAdOx1.tHIVconsv1 (C1) and ChAdOx1.HIVconsv62 (C62), are delivered by the simian adenovirus-derived vaccine vector ChAdOx1. Aberrant adenovirus RNA splicing involving transgene(s) coding for the SARS-CoV-2 spike was suggested as an aetiology of rare adverse events temporarily associated with the initial deployment of adenovirus-vectored vaccines during the COVID-19 pandemic. Here, to eliminate this theoretically plausible splicing phenomenon from the list of possible pathomechanisms for our HIV-1 vaccine candidates, we directly sequenced mRNAs in C1- and C62-infected nonpermissive MRC-5 and A549 and permissive HEK293 human cell lines. Our two main observations in nonpermissive human cells, which are most similar to those which become infected after the intramuscular administration of vaccines into human volunteers, were that (i) the dominant adenovirus vector-derived mRNAs were the expected transcripts coding for the HIVconsvX immunogens and (ii) atypical splicing events within the synthetic open reading frame of the two transgenes are rare. We conclude that inadvertent RNA splicing is not a safety concern for the two tested candidate HIV-1 vaccines.

5.
Australas J Dermatol ; 64(3): 413-416, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37185816

RESUMO

Lymphocytic thrombophilic arteritis and livedoid vasculopathy may both present with livedo racemosa and ulceration. We present 6 cases with features of both conditions, raising the possibility that they are either closely linked or are part of a spectrum of the same condition.


Assuntos
Arterite , Livedo Reticular , Trombofilia , Humanos , Livedo Reticular/etiologia , Arterite/complicações , Trombofilia/complicações , Linfócitos
8.
Nat Med ; 28(12): 2611-2621, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36302893

RESUMO

HIVACAT T-cell immunogen (HTI) is a novel human immunodeficiency virus (HIV) vaccine immunogen designed to elicit cellular immune responses to HIV targets associated with viral control in humans. The AELIX-002 trial was a randomized, placebo-controlled trial to evaluate as a primary objective the safety of a combination of DNA.HTI (D), MVA.HTI (M) and ChAdOx1.HTI (C) vaccines in 45 early-antiretroviral (ART)-treated individuals (44 men, 1 woman; NCT03204617). Secondary objectives included T-cell immunogenicity, the effect on viral rebound and the safety of an antiretroviral treatment interruption (ATI). Adverse events were mostly mild and transient. No related serious adverse events were observed. We show here that HTI vaccines were able to induce strong, polyfunctional and broad CD4 and CD8 T-cell responses. All participants experienced detectable viral rebound during ATI, and resumed ART when plasma HIV-1 viral load reached either >100,000 copies ml-1, >10,000 copies ml-1 for eight consecutive weeks, or after 24 weeks of ATI. In post-hoc analyses, HTI vaccines were associated with a prolonged time off ART in vaccinees without beneficial HLA (human leukocyte antigen) class I alleles. Plasma viral load at the end of ATI and time off ART positively correlated with vaccine-induced HTI-specific T-cell responses at ART cessation. Despite limited efficacy of the vaccines in preventing viral rebound, their ability to elicit robust T-cell responses towards HTI may be beneficial in combination cure strategies, which are currently being tested in clinical trials.


Assuntos
Vacinas contra a AIDS , Infecções por HIV , HIV-1 , Vacinas , Masculino , Feminino , Humanos , Linfócitos T CD8-Positivos , Antirretrovirais/uso terapêutico , Vacinas/uso terapêutico , Antígenos de Histocompatibilidade Classe I , Carga Viral , Linfócitos T CD4-Positivos
9.
Vaccines (Basel) ; 10(6)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35746566

RESUMO

In this study, we invented and construct novel candidate HIV-1 vaccines. Through genetic and protein engineering, we unknowingly constructed an HIV-1-derived transgene with a homopolymeric run of 11 cytidines, which was inserted into an adenovirus vaccine vector. Here, we describe the virus rescue, three rounds of clonal purification and preparation of good manufacturing practise (GMP) starting material assessed for genetic stability in five additional virus passages. Throughout these steps, quality control assays indicated the presence of the transgene in the virus genome, expression of the correct transgene product and immunogenicity in mice. However, DNA sequencing of the transgene revealed additional cytidines inserted into the original 11-cytidine region, and the GMP manufacture had to be aborted. Subsequent analyses indicated that as little as 1/25th of the virus dose used for confirmation of protein expression (106 cells at a multiplicity of infection of 10) and murine immunogenicity (108 infectious units per animal) met the quality acceptance criteria. Similar frameshifts in the expressed proteins were reproduced in a one-reaction in vitro transcription/translation employing phage T7 polymerase and E. coli ribosomes. Thus, the most likely mechanism for addition of extra cytidines into the ChAdOx1.tHIVconsv6 genome is that the adenovirus DNA polymerase lost its fidelity on a stretch of 11 cytidines, which informs future adenovirus vaccine designs.

11.
Cell Rep ; 38(9): 110449, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35235807

RESUMO

Cytotoxic T lymphocyte (CTL) and natural killer (NK) cell responses to a single optimal 10-mer epitope (KK10) in the human immunodeficiency virus type-1 (HIV-1) protein p24Gag are associated with enhanced immune control in patients expressing human leukocyte antigen (HLA)-B∗27:05. We find that proteasomal activity generates multiple length variants of KK10 (4-14 amino acids), which bind TAP and HLA-B∗27:05. However, only epitope forms ≥8 amino acids evoke peptide length-specific and cross-reactive CTL responses. Structural analyses reveal that all epitope forms bind HLA-B∗27:05 via a conserved N-terminal motif, and competition experiments show that the truncated epitope forms outcompete immunogenic epitope forms for binding to HLA-B∗27:05. Common viral escape mutations abolish (L136M) or impair (R132K) production of KK10 and longer epitope forms. Peptide length influences how well the inhibitory NK cell receptor KIR3DL1 binds HLA-B∗27:05 peptide complexes and how intraepitope mutations affect this interaction. These results identify a viral escape mechanism from CTL and NK responses based on differential antigen processing and peptide competition.


Assuntos
Infecções por HIV , HIV-1 , Sequência de Aminoácidos , Aminoácidos , Apresentação de Antígeno , Epitopos de Linfócito T , Antígenos HLA-B/genética , Humanos , Peptídeos
12.
Mol Ther Methods Clin Dev ; 21: 741-753, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34169114

RESUMO

To stop the HIV-1 pandemic, vaccines must induce responses capable of controlling vast HIV-1 variants circulating in the population as well as those evolved in each individual following transmission. Numerous strategies have been proposed, of which the most promising include focusing responses on the vulnerable sites of HIV-1 displaying the least entropy among global isolates and using algorithms that maximize vaccine match to circulating HIV-1 variants by vaccine cocktails of optimized complementing sequences. In this study, we investigated CD8 T cell responses induced by a bi-valent mosaic of highly conserved HIVconsvX regions delivered by a combination of simian adenovirus ChAdOx1 and poxvirus MVA. We compared partially and fully mono- and bi-valent prime-boost regimens and their ability to elicit T cells recognizing natural epitope variants using an interferon-γ enzyme-linked immunospot (ELISPOT) assay. We used 11 well-defined CD8 T cell epitopes in two mouse haplotypes and, for each epitope, assessed recognition of the two vaccine forms together with the other most frequent epitope variants in the HIV-1 database. We conclude that for the magnitude and depth of epitope recognition, CD8 T cell responses benefitted in most comparisons from the combined bi-valent mosaic and envisage the main advantage of the bi-valent vaccine during its deployment to diverse populations.

13.
Age Ageing ; 50(2): 423-430, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32902621

RESUMO

BACKGROUND: Following hip fracture surgery, patients from residential care are frequently excluded from inpatient rehabilitation. We aimed to assess the impact of place of residence and other factors such as frailty on rehabilitation outcomes after hip fracture surgery. METHODS: Retrospective cohort study. Outcome measures included Functional Independence Measure efficiency, discharge destination and recovery of pre-fracture mobility. Univariable and multivariable linear or logistic regression analyses were performed. SETTING: One general rehabilitation and two geriatric evaluation and management wards in a large public tertiary teaching hospital. PARTICIPANTS: A total of 844 patients who underwent inpatient rehabilitation after hip fracture surgery from 2010 to 2018. RESULTS: There were 139 (16%) patients from residential care. Being from residential care was not an independent predictor of poor outcomes. Premorbid frailty (Clinical Frailty Scale) was the strongest independent predictor of poorer Functional Independence Measure efficiency, inability to recover pre-fracture mobility and return to community dwelling. Dementia and delirium were also independently predictive of poor outcomes across all measures. Age > 90 years was independently predictive of inability to recover pre-fracture mobility and return to community dwelling. CONCLUSION: Being from residential care is not independently associated with poor outcomes following inpatient rehabilitation after hip fracture surgery and should not be the basis for excluding these patients from rehabilitation. Major predictors of poorer outcomes include premorbid frailty, dementia, delirium and age > 90 years. If able and motivated, those with potentially reversible functional limitations should be given the opportunity to participate in inpatient rehabilitation as even small gains can have a significant impact on quality of life.


Assuntos
Fragilidade , Fraturas do Quadril , Idoso , Fragilidade/diagnóstico , Fraturas do Quadril/diagnóstico , Fraturas do Quadril/cirurgia , Humanos , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento
14.
Vaccines (Basel) ; 8(3)2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32640600

RESUMO

A vaccine will likely be one of the key tools for ending the HIV-1/AIDS epidemic by preventing HIV-1 spread within uninfected populations and achieving a cure for people living with HIV-1. The currently prevailing view of the vaccine field is to introduce protective antibodies, nevertheless, a vaccine to be effective may need to harness protective T cells. We postulated that focusing a T-cell response on the most vulnerable regions of the HIV-1 proteome while maximizing a perfect match between the vaccine and circulating viruses will control HIV-1 replication. We currently use a combination of replication-deficient simian (chimpanzee) adenovirus and poxvirus modified vaccinia virus Ankara to deliver bivalent conserved-mosaic immunogens to human volunteers. Here, we exploit the mRNA platform by designing tetravalent immunogens designated as HIVconsvM, and demonstrate that mRNA formulated in lipid nanoparticles induces potent, broad and polyfunctional T-cell responses in a pre-clinical model. These results support optimization and further development of this vaccine strategy in experimental medicine trials in humans.

15.
Australas J Dermatol ; 61(4): 312-317, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32363586

RESUMO

BACKGROUND/OBJECTIVES: Acral lentiginous melanoma (ALM) is a melanoma subtype associated with atypical locations on the hands and feet and advanced disease at diagnosis. There is a limited understanding of whether the survival is similar for nail, non-nail, lower limb and upper limb ALM patients. We therefore explored clinicopathologic characteristics and melanoma-specific survival of ALM patients according to tumour location. METHODS: A prospectively collected cohort study was performed of all primary invasive cutaneous acral lentiginous melanomas with known thickness and tumour location reviewed at a tertiary referral centre over 21 years. RESULTS: A total of 101 ALM patients were reviewed from 1994 until 2016. The majority of cases (82/101) occurred on the feet. Hand ALMs were thicker and more likely to be ulcerated than feet ALMs (P = 0.05 and 0.02, respectively); however, survival was not statistically different between these two groups (univariate HR 0.48 P = 0.11, 95% CI, 0.20-1.17; multivariate HR 0.67 P = 0.40, 95% CI, 0.27-1.69, respectively). Non-nail ALM patients had longer survival when compared to nail ALM on univariate analysis (HR 0.40, 95% CI, 0.17 to 0.90) which was accounted for by Breslow thickness and ulceration (multivariate HR 0.56, 95% CI, 0.24 to 1.34). CONCLUSIONS: The reduced melanoma-specific survival in nail ALM patients was likely due to their greater thickness and ulceration. Although hand ALMs are thicker and more frequently ulcerated, this is likely due to the higher proportion of nail ALMs present in this location.


Assuntos
Melanoma/mortalidade , Neoplasias Cutâneas/mortalidade , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , , Mãos , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Neoplasias Cutâneas/patologia , Melanoma Maligno Cutâneo
16.
Front Immunol ; 11: 823, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32435247

RESUMO

Kick&kill strategies combining drugs aiming to reactivate the viral reservoir with therapeutic vaccines to induce effective cytotoxic immune responses hold potential to achieve a functional cure for HIV-1 infection. Here, we report on an open-label, single-arm, phase I clinical trial, enrolling 15 early-treated HIV-1-infected individuals, testing the combination of the histone deacetylase inhibitor romidepsin as a latency-reversing agent and the MVA.HIVconsv vaccine. Romidepsin treatment resulted in increased histone acetylation, cell-associated HIV-1 RNA, and T-cell activation, which were associated with a marginally significant reduction of the viral reservoir. Vaccinations boosted robust and broad HIVconsv-specific T cells, which were strongly refocused toward conserved regions of the HIV-1 proteome. During a monitored ART interruption phase using plasma viral load over 2,000 copies/ml as a criterium for ART resumption, 23% of individuals showed sustained suppression of viremia up to 32 weeks without evidence for reseeding the viral reservoir. Results from this pilot study show that the combined kick&kill intervention was safe and suggest a role for this strategy in achieving an immune-driven durable viremic control.


Assuntos
Vacinas contra a AIDS/imunologia , Antivirais/uso terapêutico , Depsipeptídeos/uso terapêutico , Infecções por HIV/imunologia , HIV-1/fisiologia , Inibidores de Histona Desacetilases/uso terapêutico , Adulto , Reservatórios de Doenças , Quimioterapia Combinada , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Carga Viral , Viremia , Latência Viral
17.
J Am Acad Dermatol ; 83(2): 501-508, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32044177

RESUMO

BACKGROUND: Lymphocytic thrombophilic arteritis (LTA), or macular lymphocytic arteritis, is defined by a primary lymphocytic vasculitis. However, the nosology of LTA has been controversial, with speculation that it may represent an indolent non-nodule-forming variant of cutaneous polyarteritis nodosa (cPAN). OBJECTIVE: This study compares the clinicopathologic features of patients with LTA or cPAN to assess if these conditions should be considered distinct entities. METHODS: This is a cross-sectional study of all LTA and cPAN cases at a single tertiary center using prospectively collected clinical data and blinded histologic assessment. RESULTS: The study included 17 patients with LTA and 13 patients with cPAN. Clinically, cases of LTA were distinguished by a more widespread pattern of livedo racemosa, which was noninfiltrated and asymptomatic. In contrast, cPAN was associated with localized starburst livedo, purpura, and episodic features including nodules, pain, and large inflammatory ulcers. When patients were separated according to the presence (>5%) or paucity (≤5%) of neutrophils on blinded histology review, they had distinct clinical features and differences in disease course. LIMITATIONS: This was a single-center study. CONCLUSION: Our data support the classification of LTA and cPAN as separate entities rather than a spectrum of the same disorder and highlight the importance of clinicopathologic correlation in distinguishing these conditions.


Assuntos
Arterite/diagnóstico , Linfócitos/patologia , Poliarterite Nodosa/diagnóstico , Pele/patologia , Trombofilia/diagnóstico , Adulto , Arterite/sangue , Arterite/complicações , Arterite/patologia , Estudos Transversais , Diagnóstico Diferencial , Progressão da Doença , Feminino , Humanos , Livedo Reticular/etiologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/patologia , Poliarterite Nodosa/complicações , Poliarterite Nodosa/patologia , Estudos Prospectivos , Púrpura/etiologia , Pele/irrigação sanguínea , Pele/citologia , Trombofilia/sangue , Trombofilia/complicações , Trombofilia/patologia , Adulto Jovem
19.
Australas J Dermatol ; 61(2): 125-133, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31880825

RESUMO

BACKGROUND/OBJECTIVES: There is evidence that cutaneous melanomas at different anatomic sites present with distinctive clinicopathologic features. We examined the anatomic distribution of cutaneous melanoma and its variation by patient characteristics, subtype and Breslow thickness, using high-resolution anatomic site data. METHODS: A cross-sectional study was performed of all primary cutaneous melanoma cases managed at a tertiary referral centre, analysing prospectively collected clinical data across 50 anatomic subsites. RESULTS: The study included 5141 in situ or invasive melanomas; most were invasive (76.2%), and the median Breslow thickness of invasive lesions was 1.0 mm. Superficial spreading (57.2%), lentigo maligna (20.8%) and nodular (12.2%) were the most common histopathological subtypes. Sun-exposed sites such as the female nose and cheek, the male ear, as well as the upper back in both sexes had the highest incidence of melanoma per unit area. When compared to the posterior forearm, the scalp, ear, preauricular, perioral, subungual and plantar sites had thicker invasive melanomas (each P < 0.05). The peri-auricular, ear and cheek had the highest incidence of nodular melanoma per unit area. There were subtype-, age- and sex-specific differences in melanoma anatomic distribution. CONCLUSION: Melanoma most commonly arises in sun-exposed facial areas, as well as the upper back. Increased thickness is found for melanoma in acral and many head and neck sites. Nodular melanoma is more likely to occur in head and neck sites including the peri-auricular area, ear and cheek. Clinicians should carefully assess these sites during skin examinations.


Assuntos
Neoplasias Faciais/patologia , Neoplasias de Cabeça e Pescoço/patologia , Melanoma/patologia , Neoplasias Cutâneas/patologia , Bochecha/patologia , Humanos , Invasividade Neoplásica , Estadiamento de Neoplasias , Couro Cabeludo/patologia , Fatores Sexuais , Melanoma Maligno Cutâneo
20.
Mol Ther Methods Clin Dev ; 14: 148-160, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31367651

RESUMO

The aim of this work was to start collecting information on rational combination of antibody (Ab) and T cell vaccines into single regimens. Two promising candidate HIV-1 vaccine strategies, sequential isolates of CH505 virus Envs developed for initiation of broadly neutralizing antibody lineages and conserved-mosaic tHIVconsvX immunogens aiming to induce effective cross-clade T cell responses, were combined to assess vaccine interactions. These immunogens were delivered in heterologous vector/modality regimens consisting of non-replicating simian (chimpanzee) adenovirus ChAdOx1 (C), non-replicating poxvirus MVA (M), and adjuvanted protein (P). Outbred CD1-SWISS mice were vaccinated intramuscularly using either parallel CM8M (tHIVconsvX)/CPPP (CH505) or sequential CM16M (tHIVconsvX)/CPPP (CH505) protocols, the latter of which delivered T cell CM prior to the CH505 Env. CM8M (tHIVconsvX) and CPPP or CMMP (CH505) vaccinations alone were included as comparators. The vaccine-elicited HIV-1-specific trimer-binding and neutralizing Abs and CD8+/CD4+ T cell responses induced by the combined and comparator regimens were not statistically separable among regimens. The Ab-lineage immunogen strategy was particularly suited for combined regimens for its likely less potent induction of Env-specific T cell responses relative to homologous epitope-based vaccine strategies. These results inform design of the first rationally combined Ab and T cell vaccine regimens in human volunteers.

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