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2.
J Infect Dis ; 204(10): 1541-9, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21940420

RESUMO

BACKGROUND: To investigate the potential immunostimulatory effect of interleukin (IL) 2 as a human immunodeficiency virus type 1 (HIV-1) vaccine adjuvant, we conducted a study of a plasmid coding for a fusion protein of IL-2 and immunoglobulin (IL-2/Ig). METHODS: This phase I trial evaluated an HIV-1 DNA vaccine with the plasmid cytokine adjuvant (IL-2/Ig) in 70 HIV-negative adults. Subjects received placebo (group C), adjuvant alone (group A), vaccine alone (group D), increasing doses of adjuvant concurrent with vaccine (groups T1-T4), or adjuvant given 2 days after vaccine (group T5). RESULTS: No significant differences in adverse events were observed between treatment groups. Cellular immune responses to envelope protein EnvA peptides were detected by interferon (IFN) γ and IL-2 enzyme-linked immunospot (ELISPOT) assays in 50% and 40% of subjects, respectively, in T4, and in 100% and 80% in T5. The median responses for groups T4 and T5, respectively, were 90 and 193 spot-forming cells (SFCs)/106 peripheral blood mononuclear cells (P = .004; T4 vs T5) for the IL-2 ELISPOT assay and 103 and 380 SFCs/106 PBMCs (P = .003; T4 vs T5) for the IFN-γ ELISPOT assay. A trend to more durable cellular immune responses in T5 was observed at 1 year (T5 vs T4/D; P = .07). Higher anti-Env antibody responses were detected with T5 than with T4. CONCLUSIONS: Plasmid IL-2/Ig significantly increased immune responses when administered 2 days after the DNA vaccine, compared with simultaneous administration. These observations have important implications for the development of cytokine augmentation strategies. CLINICAL TRIALS REGISTRATION: NCT00069030.


Assuntos
Vacinas contra a AIDS/imunologia , Adjuvantes Imunológicos/administração & dosagem , Soronegatividade para HIV/imunologia , HIV-1/imunologia , Interleucina-2/administração & dosagem , Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/efeitos adversos , Adolescente , Adulto , Anticorpos Antivirais/análise , Método Duplo-Cego , Ensaio de Imunoadsorção Enzimática , ELISPOT , Feminino , Humanos , Interleucina-2/imunologia , Masculino , Plasmídeos/administração & dosagem , Linfócitos T/imunologia , Linfócitos T/metabolismo , Vacinas de DNA/administração & dosagem , Vacinas de DNA/efeitos adversos , Vacinas de DNA/imunologia , Proteínas do Envelope Viral/análise , Adulto Jovem
3.
AIMS Public Health ; 9(2): 342-356, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634028

RESUMO

Healthcare workers are at a high risk of violence all over the world. The hostility toward nurses, physicians, and hospital staff has reached the point that it can be considered a public health problem. In this paper, we focus on the harassment, aggression, and violence that many healthcare workers have encountered while treating unstable psychiatric patients in the middle of the COVID-19 pandemic. We present a case with a history of violence toward mental health workers, review psychopathological and clinical aspects, and discuss how both the COVID-19 pandemic and current challenges in psychiatric hospital settings increase the frequency and severity of these attacks and how this affects the team on inpatient psychiatric units. We used the CARE guidelines to provide the most accurate and transparent information about the patient and relevant psychosocial aspects. We also pooled more than 20 unique sources to cover all aspects of violent behaviors in all psychiatric settings for all age groups. We concluded that a lack of nursing staff, the mental burden imposed by difficult patients, and poor communication between team members are some of the factors contributing to patient violence. An incomplete understanding of the problem creates barriers to change on both personal and systematic levels. Constant violence and abuse against healthcare workers cause stress, decreased productivity, and work dissatisfaction. To improve the safety of healthcare professionals, especially in inpatient psychiatric settings, several system-based changes should be implemented.

4.
Psychiatry J ; 2022: 3884317, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35495616

RESUMO

Malingering is the intentional production of false or grossly exaggerated physical or psychological symptoms motivated by external incentives. Although the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) does not list malingering in its diagnostic section and therefore does not identify it as a formal mental disorder, malingering and verified mental illness commonly coexist. Some subtypes of feigning behaviors, such as partial or pure malingering, dissimulation, and false imputation, can be suspected when patients have marked discrepancies between reported stressors and objective findings. The article discusses these three theoretical concepts with their possible clinical aspects, illustrating each phenomenon by clinical case with self-reported and/or observed psychotic symptoms. We summarized relevant findings and provided a review of clinical considerations that physicians can use to aid in the evaluation of psychotic symptoms in the context of those three concepts.

5.
World J Oncol ; 12(5): 137-148, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34804276

RESUMO

In this review, we first present a case of chronic myeloid leukemia with acute psychosis, and then we will discuss the incidence of cancer in patients with psychotic disorders, the manifestations of new-onset psychosis, and the prevalence of preexisting psychosis in cancer patients, coupled with their impact on the treatment, diagnosis, and prognosis of cancer. This was a case that presented with acute psychosis and was found to have an elevated white blood cell count upon admission to an inpatient psychiatric unit. He was diagnosed with chronic myeloid leukemia and successfully managed with imatinib/dasatinib therapy. Psychiatrically, he was stabilized on two long-acting injectable medications to help maintain adherence. We were able to eliminate his active psychotic symptoms and return him to normal functioning in affect and thinking, achieving sustained compliance with treatment. We identified multiple inconsistencies in screening for cancer of all types in these patients, masking of signs and symptoms that would typically clue physicians to the presence of cancers, underreporting of symptoms, and disparate access to healthcare resources in patients with mental disorders when compared to the general population. Treatment of cancer in these patients as compared to the general population has also been shown to be incongruent, which will be elaborated upon. Psychiatric interventions, as well as supportive measures, for treating patients who are facing challenges during active cancer treatment will be discussed.

7.
Contemp Clin Trials ; 27(2): 147-60, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16426900

RESUMO

The HIV pandemic is a pressing threat to global public health; HIV vaccine development is critical. Clinical evaluation of HIV vaccine candidates differs from the standard therapeutics trial framework primarily due to the fact that healthy individuals are studied. We present an early stage evaluation program developed for the HIV Vaccine Trials Network (HVTN) motivated by characteristics unique to the vaccine setting. The program consists of 3 prototypical stages (Phase I, Ib, II) that provide a unified yet flexible approach to the safety and immunogenicity evaluation of diverse vaccine regimens. The goal of these early trials is to narrow the number of candidate vaccines to the most promising candidates worthy of further study in efficacy trials.


Assuntos
Vacinas contra a AIDS/uso terapêutico , Ensaios Clínicos Fase I como Assunto/métodos , Ensaios Clínicos Fase II como Assunto/métodos , Interpretação Estatística de Dados , Vacinas contra a AIDS/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Anticorpos Anti-HIV/sangue , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Humanos , Linfócitos T/imunologia
8.
Curr Opin HIV AIDS ; 11(6): 614-619, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27636503

RESUMO

PURPOSE OF REVIEW: The purpose of review is to provide an overview of the Pox-Protein Public Private Partnership (P5) and highlight the progress of the P5 program, including an upcoming HIV vaccine efficacy trial in South Africa. RECENT FINDINGS: The RV144 Thai vaccine efficacy trial was the first to demonstrate that an HIV-1 vaccine can prevent HIV acquisition. The P5 vaccine regimen uses an ALVAC prime and protein boost modeled after the RV144 vaccine and adapted for the subtype C virus predominant in the southern African region. This regimen was recently tested in the HIV Vaccine Trials Network 100 phase 1/2a study in South Africa. Based on prospectively defined immunogenicity thresholds, criteria were met to support the launch of an efficacy study in late 2016. The aim of this phase 2b/3 trial will be to improve upon the results of RV144, with increased and more durable vaccine efficacy, to accelerate the potential licensure of a preventive vaccine in southern Africa. SUMMARY: The planned P5 efficacy trial, HIV Vaccine Trials Network 702, is designed to test and prospectively define correlates of protection, if efficacious. A vaccine with modest efficacy, vaccine efficacy at least 50%, could have substantial public health impact and significantly decrease the incidence of new infections in heavily burdened areas of the world.


Assuntos
Vacinas contra a AIDS/imunologia , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Infecções por HIV/prevenção & controle , Parcerias Público-Privadas , Vacinas contra a AIDS/administração & dosagem , Biomarcadores , HIV-1/imunologia , Humanos , África do Sul , Resultado do Tratamento
10.
J Immunol Methods ; 288(1-2): 19-34, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15183082

RESUMO

Effector T lymphocyte responses are considered critical for controlling human immunodeficiency virus type-1 (HIV-1) infection. The enzyme-linked immunospot (ELISpot) assay has emerged as a primary means of assessing HIV-specific T cell responses, and the development of objective methods that distinguish positive and negative ELISpot responses while properly controlling the rate of false positives is critical. In this paper, we consider several statistical methods that are helpful in defining such a positive criterion. Simulation results under a variety of scenarios suggest that a permutation-based criterion using a resampling adjustment for multiple comparisons yields the desired false positive rate while remaining competitive with other potential criteria in terms of sensitivity. These results also provide guidance on the effect of the number of experimental and negative control replicate wells on assay sensitivity. Application of different potential positive criteria using ELISpot assay results from IFN-gamma-secreting T cells of HIV-1 seropositive and seronegative donors confirmed several of the results obtained under simulation. Our findings support the application of statistically-based positive criteria such as the permutation-based resampling approach in assessing HIV vaccine-induced T cell responses. Moreover, the proposed methods have potential utility in related HIV immunopathogenesis studies and in non-HIV clinical vaccine trials.


Assuntos
Sorodiagnóstico da AIDS/métodos , Vacinas contra a AIDS/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Anticorpos Anti-HIV/análise , HIV-1/imunologia , Interpretação Estatística de Dados , Anticorpos Anti-HIV/imunologia , Humanos
11.
AIDS Res Hum Retroviruses ; 30(11): 1017-22, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24857015

RESUMO

Empirical testing of candidate vaccines has led to the successful development of a number of lifesaving vaccines. The advent of new tools to manipulate antigens and new methods and vectors for vaccine delivery has led to a veritable explosion of potential vaccine designs. As a result, selection of candidate vaccines suitable for large-scale efficacy testing has become more challenging. This is especially true for diseases such as dengue, HIV, and tuberculosis where there is no validated animal model or correlate of immune protection. Establishing guidelines for the selection of vaccine candidates for advanced testing has become a necessity. A number of factors could be considered in making these decisions, including, for example, safety in animal and human studies, immune profile, protection in animal studies, production processes with product quality and stability, availability of resources, and estimated cost of goods. The "immune space template" proposed here provides a standardized approach by which the quality, level, and durability of immune responses elicited in early human trials by a candidate vaccine can be described. The immune response profile will demonstrate if and how the candidate is unique relative to other candidates, especially those that have preceded it into efficacy testing and, thus, what new information concerning potential immune correlates could be learned from an efficacy trial. A thorough characterization of immune responses should also provide insight into a developer's rationale for the vaccine's proposed mechanism of action. HIV vaccine researchers plan to include this general approach in up-selecting candidates for the next large efficacy trial. This "immune space" approach may also be applicable to other vaccine development endeavors where correlates of vaccine-induced immune protection remain unknown.


Assuntos
Doenças Transmissíveis/epidemiologia , Descoberta de Drogas/métodos , Descoberta de Drogas/normas , Vacinas/imunologia , Vacinas/isolamento & purificação , Animais , Ensaios Clínicos como Assunto , Humanos , Vacinação/métodos , Vacinas/efeitos adversos
12.
Clin Vaccine Immunol ; 21(11): 1589-99, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25253665

RESUMO

Finding an effective human immunodeficiency virus type 1 (HIV-1) vaccine remains a major global health priority. In a phase I/II, placebo-controlled trial, healthy, HIV-1-negative adults were randomized to receive one of 5 vaccine regimens: LIPO-5 (combination of 5 lipopeptides) alone (250 µg), ALVAC-HIV (vCP1452) alone, or 3 groups of ALVAC-HIV (vCP1452) followed by ALVAC-HIV (vCP1452) plus LIPO-5 (250, 750, and 2,500 µg). Only 73/174 participants (42%) received all four vaccinations due to a study halt related to myelitis. There were no significant differences in systemic reactions between groups or in local reactogenicity between groups receiving ALVAC-HIV (vCP1452). Significant differences in local reactogenicity occurred between groups receiving LIPO-5 (P ≤ 0.05). Gag and Env antibodies were undetectable by ELISA 2 weeks after the fourth vaccination for all but one recipient. Antibodies to Gag and Env were present in 32% and 24% of recipients of ALVAC-HIV (vCP1452) alone and in 47% and 35% of ALVAC-HIV (vCP1452)+LIPO recipients, respectively. Coadministration of LIPO-5 did not significantly increase the response rate compared to ALVAC-HIV (vCP1452) alone, nor was there a significant relationship between dose and antibody responses among ALVAC-HIV (vCP1452)+LIPO groups. Over 90% of study participants had no positive gamma interferon (IFN-γ) enzyme-linked immunosorbent spot assay (ELISpot) responses to any peptide pool at any time point. The study was halted due to a case of myelitis possibly related to the LIPO-5 vaccine; this case of myelitis remains an isolated event. In general, there was no appreciable cell-mediated immunity detected in response to the vaccines used in this study, and antibody responses were limited. The clinical trial is registered on ClinicalTrials.gov with registry number NCT00076063.


Assuntos
Vacinas contra a AIDS/efeitos adversos , Vacinas contra a AIDS/imunologia , Síndrome da Imunodeficiência Adquirida/prevenção & controle , HIV-1/imunologia , Vacinação/efeitos adversos , Vacinação/métodos , Vacinas contra a AIDS/administração & dosagem , Adolescente , Adulto , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Ensaio de Imunoadsorção Enzimática , ELISPOT , Feminino , Anticorpos Anti-HIV/sangue , Humanos , Interferon gama/metabolismo , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Resultado do Tratamento , Adulto Jovem
13.
Curr Opin HIV AIDS ; 8(5): 421-31, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23743791

RESUMO

PURPOSE OF REVIEW: Considerable HIV-1 vaccine development efforts have been deployed over the past decade. Put into perspective, the results from efficacy trials and the identification of correlates of risk have opened large and unforeseen avenues for vaccine development. RECENT FINDINGS: The Thai efficacy trial, RV144, provided the first evidence that HIV-1 vaccine protection against HIV-1 acquisition could be achieved. The correlate of risk analysis showed that IgG antibodies against the gp120 V2 loop inversely correlated with a decreased risk of infection, whereas Env-specific IgA directly correlated with risk. Further clinical trials will focus on testing new envelope subunit proteins formulated with adjuvants capable of inducing higher and more durable functional antibody responses (both binding and broadly neutralizing antibodies). Moreover, vector-based vaccine regimens that can induce cell-mediated immune responses in addition to humoral responses remain a priority. SUMMARY: Future efficacy trials will focus on prevention of HIV-1 transmission in heterosexual population in Africa and MSM in Asia. The recent successes leading to novel directions in HIV-1 vaccine development are a result of collaboration and commitment among vaccine manufacturers, funders, scientists and civil society stakeholders. Sustained and broad collaborative efforts are required to advance new vaccine strategies for higher levels of efficacy.


Assuntos
Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/imunologia , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Vacinas contra a AIDS/efeitos adversos , Vacinas contra a AIDS/genética , África , Ásia , Ensaios Clínicos como Assunto , Anticorpos Anti-HIV/sangue , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/genética , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia
14.
Vaccine ; 31 Suppl 2: B204-8, 2013 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-23598483

RESUMO

Human immunodeficiency virus (HIV), the etiologic agent that causes AIDS, is the fourth largest killer in the world today. Despite the remarkable achievements in development of anti-retroviral therapies against HIV, and the recent advances in new prevention technologies, the rate of new HIV infections continue to outpace efforts on HIV prevention and control. Thus, the development of a safe and effective vaccine for prevention and control of AIDS remains a global public health priority and the greatest opportunity to eventually end the AIDS pandemic. Currently, there is a renaissance in HIV vaccine development, due in large part to the first demonstration of vaccine induced protection, albeit modest, in human efficacy trials, a generation of improved vaccine candidates advancing in the clinical pipeline, and newly defined targets on HIV for broadly neutralizing antibodies. The main barriers to HIV vaccine development include the global variability of HIV, lack of a validated animal model, lack of correlates of protective immunity, lack of natural protective immune responses against HIV, and the reservoir of infected cells conferred by integration of HIV's genome into the host. Some of these barriers are not unique to HIV, but generic to other variable viral pathogens such as hepatitis C and pandemic influenza. Recommendations to overcome these barriers are presented in this document, including but not limited to expansion of efforts to design immunogens capable of eliciting broadly neutralizing antibodies against HIV, expansion of clinical research capabilities to assess multiple immunogens concurrently with comprehensive immune monitoring, increased support for translational vaccine research, and engaging industry as full partners in vaccine discovery and development.


Assuntos
Vacinas contra a AIDS/uso terapêutico , Pesquisa Biomédica/tendências , Infecções por HIV/prevenção & controle , Anticorpos Neutralizantes/imunologia , Saúde Global , Anticorpos Anti-HIV/imunologia , Humanos
15.
Vaccine ; 28(30): 4786-97, 2010 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-20471439

RESUMO

An effective HIV vaccine will be essential for the control of the HIV pandemic. This study evaluated the potential global market size and value of a hypothetical HIV vaccine and considered clade diversity, disease burden, partial prevention of acquisition, impact of a reduction in viral load resulting in a decrease in transmission and delay to treatment, health care system differences regarding access, and HIV screening and vaccination, across all public and private markets. Vaccine product profiles varied from a vaccine that would have no effect on preventing infection to a vaccine that would effectively prevent infection and reduce viral load. High disease burden countries (HDBC; HIV prevalence > or = 1%) were assumed to routinely vaccinate pre-sexually active adolescents (10 years old), whereas low disease burden countries (LDBC; HIV prevalence rate <1%) were assumed to routinely vaccinate higher risk populations only. At steady state, routine vaccination demand for vaccines that would prevent infection only was 22-61 million annual doses with a potential market value of $210 million to $2.7 billion, depending on the vaccine product profile. If one-time catch-up campaigns were included (11-14 years old for HDBC and higher risk groups for LDBC), the additional cumulative approximately 70-237 million doses were needed over a 10-year period with a potential market value of approximately $695 million to $13.4 billion, depending on the vaccine product profile. Market size and value varied across market segments with the majority of the value in high income countries and the majority of the demand in low income countries. However, the value of the potential market in low income countries is still significant with up to $550 million annually for routine vaccination only and up to $1.7 billion for a one-time only catch-up campaign in 11-14 years old. In the most detail to date, this study evaluated market size and value of a potential multi-clade HIV vaccine, accounting for differences in disease burden, product profile and health care complexities. These findings provide donors and suppliers highly credible new data to consider in their continued efforts to develop an HIV-1 vaccine to address the worldwide disease burden.


Assuntos
Vacinas contra a AIDS/economia , Vacinas contra a AIDS/uso terapêutico , Infecções por HIV/economia , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Setor de Assistência à Saúde/estatística & dados numéricos , Saúde Pública , Adolescente , Adulto , Criança , Países em Desenvolvimento , Custos de Medicamentos , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Vacinação , Carga Viral , Adulto Jovem
16.
PLoS One ; 5(10): e13579, 2010 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-21048953

RESUMO

BACKGROUND: Individuals without prior immunity to a vaccine vector may be more sensitive to reactions following injection, but may also show optimal immune responses to vaccine antigens. To assess safety and maximal tolerated dose of an adenoviral vaccine vector in volunteers without prior immunity, we evaluated a recombinant replication-defective adenovirus type 5 (rAd5) vaccine expressing HIV-1 Gag, Pol, and multiclade Env proteins, VRC-HIVADV014-00-VP, in a randomized, double-blind, dose-escalation, multicenter trial (HVTN study 054) in HIV-1-seronegative participants without detectable neutralizing antibodies (nAb) to the vector. As secondary outcomes, we also assessed T-cell and antibody responses. METHODOLOGY/PRINCIPAL FINDINGS: Volunteers received one dose of vaccine at either 10(10) or 10(11) adenovector particle units, or placebo. T-cell responses were measured against pools of global potential T-cell epitope peptides. HIV-1 binding and neutralizing antibodies were assessed. Systemic reactogenicity was greater at the higher dose, but the vaccine was well tolerated at both doses. Although no HIV infections occurred, commercial diagnostic assays were positive in 87% of vaccinees one year after vaccination. More than 85% of vaccinees developed HIV-1-specific T-cell responses detected by IFN-γ ELISpot and ICS assays at day 28. T-cell responses were: CD8-biased; evenly distributed across the three HIV-1 antigens; not substantially increased at the higher dose; and detected at similar frequencies one year following injection. The vaccine induced binding antibodies against at least one HIV-1 Env antigen in all recipients. CONCLUSIONS/SIGNIFICANCE: This vaccine appeared safe and was highly immunogenic following a single dose in human volunteers without prior nAb against the vector. TRIAL REGISTRATION: ClinicalTrials.gov NCT00119873.


Assuntos
Vacinas contra a AIDS/efeitos adversos , Adenoviridae/imunologia , Vírus Defeituosos/imunologia , Adulto , Anticorpos Neutralizantes/imunologia , Método Duplo-Cego , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Placebos , Linfócitos T/imunologia
17.
Vaccine ; 26(2): 215-23, 2008 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-18055072

RESUMO

We evaluated EP HIV-1090 vaccine, a DNA plasmid encoding 21 cytotoxic T-lymphocyte (CTL) epitopes of human immunodeficiency virus type 1 (HIV-1) and the pan-DR helper T-lymphocyte epitope (PADRE), in a dose escalation, randomized, double-blinded, placebo-controlled Phase 1 trial. Vaccine, at 0.5, 2.0, or 4.0mg doses, or placebo was injected four times over 6 months. Forty-two healthy, HIV-1-uninfected adults were enrolled. Using an interferon-gamma ELISPOT assay, a response to PADRE was detected in one vaccine recipient. Three vaccine recipients raised anti-HIV-1 CD8+ CTL measured by chromium-release assay. The vaccine was safe and well-tolerated, but only weakly immunogenic.


Assuntos
Vacinas contra a AIDS/efeitos adversos , Vacinas contra a AIDS/imunologia , Epitopos de Linfócito T/imunologia , Vacinas de DNA/efeitos adversos , Vacinas de DNA/imunologia , Vacinas contra a AIDS/genética , Adolescente , Adulto , Células Cultivadas , Testes Imunológicos de Citotoxicidade , Método Duplo-Cego , Epitopos de Linfócito T/genética , Feminino , Infecções por HIV/prevenção & controle , HIV-1/genética , HIV-1/imunologia , Humanos , Interferon gama/biossíntese , Leucócitos Mononucleares/imunologia , Masculino , Plasmídeos/administração & dosagem , Linfócitos T Citotóxicos/imunologia , Vacinas de DNA/genética
18.
J Acquir Immune Defic Syndr ; 44(2): 203-12, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17106277

RESUMO

BACKGROUND: A goal of T-cell HIV vaccines is to define the correlation between a vaccine-induced immune response and protection from HIV infection. We conducted a phase 2 trial to determine if a canarypox vaccine candidate (vCP1452) administered with rgp120 subunit protein would "qualify" for a trial to define a correlate of efficacy. METHODS: A total of 330 healthy volunteers were enrolled into 4 groups: 120 received vCP1452 alone (0, 1, 3, and 6 months), 120 received vCP1452 with 2 different regimens of rgp120 coadministration, and 90 received placebo. HIV-specific antibody responses were measured by enzyme-linked immunoassay (ELISA) and neutralizing activity. T-cell responses were measured by chromium release and interferon-gamma (IFNgamma) enzyme-linked immunospot (ELISpot) assay. RESULTS: Significant neutralizing antibody responses to the HIV MN strain were detected in all vaccine groups, with net responses ranging from 57% (95% confidence interval [CI]: 40% to 71%) to 94% (95% CI: 85% to 99%). Net cumulative HIV-specific CD8 IFNgamma ELISpot assay responses were 13% (95% CI: -1% to 26%) for recipients of vCP1452 alone and 16% (95% CI: 2% to 29%) for recipients of vCP1452 plus rgp120. CONCLUSIONS: Overall, the HIV-specific CD8 cytotoxic T lymphocyte (CTL) response was not sufficient to qualify the regimen for a subsequent trial designed to detect an immune correlate of protection requiring a minimum CD8 CTL frequency of 30%.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Anti-HIV/sangue , Proteína gp120 do Envelope de HIV/imunologia , HIV-1/imunologia , Linfócitos T Citotóxicos/imunologia , Vacinas contra a AIDS/efeitos adversos , Adolescente , Adulto , Linfócitos T CD4-Positivos/imunologia , Vírus da Varíola dos Canários/genética , Cromo/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Vetores Genéticos , Humanos , Interferon gama/biossíntese , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , Vacinas de Subunidades Antigênicas/imunologia , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/imunologia
19.
J Infect Dis ; 187(2): 226-42, 2003 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-12552447

RESUMO

There is evidence in both simian immunodeficiency virus and human immunodeficiency virus (HIV) type 1 infection that class I major histocompatibility complex-restricted CD8(+) cytotoxic T lymphocytes play a pivotal role in controlling infection and, potentially, in protecting by immunization. Progress has been made in designing strategies to elicit these responses with HIV-1 vaccines, but methods to reproducibly quantify them have posed difficulties. An interferon-gamma enzyme-linked immunospot assay, using peptide pools spanning the HIV-1 genes, was developed and standardized. This method is rapid (2 days), sensitive (threshold of detection, > or =0.005%), quantitative, feasible using cryopreserved cells, and able to define epitope specificities. When this assay was applied to 36 HIV-1-seropositive and 10 HIV-1-seronegative subjects, it proved to be robust (specificity, 100%). When responses in natural infection were compared with vaccine-induced responses, vaccine recipient responses were > or =1 log lower, which confirms the importance of using this sensitive assay as an initial screen in vaccine protocols.


Assuntos
Vacinas contra a AIDS/imunologia , Linfócitos T CD8-Positivos/imunologia , HIV-1/imunologia , Células Cultivadas , Ensaios Clínicos como Assunto , Relação Dose-Resposta Imunológica , Epitopos de Linfócito T/imunologia , Antígenos HIV/química , Antígenos HIV/imunologia , Humanos , Interferon gama/imunologia , Ativação Linfocitária , Peptídeos/química , Peptídeos/imunologia , Fatores de Tempo
20.
J Infect Dis ; 190(9): 1692-6, 2004 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-15478077

RESUMO

ELISpot and intracellular cytokine staining are replacing the traditional cytolytic ((51)Cr release) assay method in vaccine trials using human immunodeficiency virus (HIV)-1, and it is widely assumed that the number of interferon (IFN)- gamma -secreting T cells is a surrogate for the level of cytolytic activity. Thus, we sought to determine whether the detection of IFN- gamma in CD8(+) T cells correlates with cytolytic ability in vitro. In 29 (69.0%) of 42 HIV-1-seronegative immunocompetent individuals (22 unvaccinated and 20 vaccinated), virus-specific T cell responses recognizing cytomegalovirus, Epstein-Barr virus, and influenza and HIV-1 Gag epitopes were detected by at least 1 assay method (ELISpot, intracellular cytokine staining, and/or (51)Cr release), and 18 (62.1%) of these 29 demonstrated both IFN- gamma secretion and cytolysis. There was strong correlation between the results of IFN- gamma ELISpot and those of IFN- gamma intracellular cytokine staining ( rho =0.88) and between the results of (51)Cr release and those of intracellular cytokine staining ( rho =0.81); although the correlation is not absolute, intracellular cytokine staining can be used--and is superior to ELISpot--as a surrogate for cytolytic assays.


Assuntos
Citotoxicidade Imunológica , Memória Imunológica , Interferon gama/análise , Linfócitos T Citotóxicos/imunologia , Antígenos Virais/imunologia , Biomarcadores/análise , Citomegalovirus/imunologia , Testes Imunológicos de Citotoxicidade , HIV/imunologia , Herpesvirus Humano 4/imunologia , Humanos , Interferon gama/metabolismo , Orthomyxoviridae/imunologia , Coloração e Rotulagem/métodos
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