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1.
Acad Psychiatry ; 47(1): 48-52, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35918600

RESUMO

OBJECTIVE: During the COVID-19 pandemic, psychiatry programs have administered the Clinical Skills Evaluation (CSE) through videoconferencing. The authors evaluated the feasibility and appropriateness of administering virtual CSEs. METHODS: Virtual CSEs were administered to 11 general psychiatry residents on March 16, 2021. Teleconference software was used to connect faculty at work sites, residents at a simulation center, and volunteer patients at home. Before and after the CSE, residents and faculty were surveyed with Likert scale questions to evaluate their perceptions and experience. RESULTS: All virtual CSEs were completed successfully. Nine residents (82%) and 12 faculty (92%) responded to both surveys. Most participants (range, 67-83%) indicated that the virtual CSE was appropriate for assessing patient health and resident skills. Most participants (range, 56-100%) reported that the opening and closing of the interview, informational and affective cues, and rapport were adequately assessed. All participants agreed that suicidal and homicidal risks could be adequately assessed. Most faculty and residents (76%) believed that unique skills were required for telehealth interviews. Before the CSE, more faculty than residents believed that they received adequate training for the virtual CSE (P=.02); afterward, most participants thought that training was adequate (P=.46). More faculty than residents reported increased convenience with virtual assessments (both surveys, P<.01). CONCLUSION: Virtual CSEs were deemed feasible and appropriate. Further research is needed to identify the specific skills required to perform a virtual CSE and to clarify the potential limitations and benefits of this format.


Assuntos
COVID-19 , Internato e Residência , Psiquiatria , Humanos , Competência Clínica , Pandemias , Psiquiatria/educação , Docentes de Medicina
2.
PLoS One ; 7(1): e30229, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22279573

RESUMO

BACKGROUND: Using in vivo mouse models, the mechanisms of CD4+ T cell help have been intensively investigated. However, a mechanistic analysis of human CD4+ T cell help is largely lacking. Our goal was to elucidate the mechanisms of human CD4+ T cell help of CD8+ T cell proliferation using a novel in vitro model. METHODS/PRINCIPAL FINDINGS: We developed a genetically engineered novel human cell-based artificial APC, aAPC/mOKT3, which expresses a membranous form of the anti-CD3 monoclonal antibody OKT3 as well as other immune accessory molecules. Without requiring the addition of allogeneic feeder cells, aAPC/mOKT3 enabled the expansion of both peripheral and tumor-infiltrating T cells, regardless of HLA-restriction. Stimulation with aAPC/mOKT3 did not expand Foxp3+ regulatory T cells, and expanded tumor infiltrating lymphocytes predominantly secreted Th1-type cytokines, interferon-γ and IL-2. In this aAPC-based system, the presence of autologous CD4+ T cells was associated with significantly improved CD8+ T cell expansion in vitro. The CD4+ T cell derived cytokines IL-2 and IL-21 were necessary but not sufficient for this effect. However, CD4+ T cell help of CD8+ T cell proliferation was partially recapitulated by both adding IL-2/IL-21 and by upregulation of IL-21 receptor on CD8+ T cells. CONCLUSIONS: We have developed an in vitro model that advances our understanding of the immunobiology of human CD4+ T cell help of CD8+ T cells. Our data suggests that human CD4+ T cell help can be leveraged to expand CD8+ T cells in vitro.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Complexo CD3/imunologia , Complexo CD3/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Células Cultivadas , Técnicas de Cocultura , Citocinas/imunologia , Citocinas/metabolismo , Citometria de Fluxo , Humanos , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-2/imunologia , Interleucina-2/metabolismo , Interleucina-2/farmacologia , Interleucinas/imunologia , Interleucinas/metabolismo , Interleucinas/farmacologia , Células K562 , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Muromonab-CD3/imunologia , Muromonab-CD3/metabolismo , Muromonab-CD3/farmacologia , Receptores de Interleucina-21/imunologia , Receptores de Interleucina-21/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Regulação para Cima/efeitos dos fármacos
3.
Sci Transl Med ; 3(80): 80ra34, 2011 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-21525398

RESUMO

Although advanced-stage melanoma patients have a median survival of less than a year, adoptive T cell therapy can induce durable clinical responses in some patients. Successful adoptive T cell therapy to treat cancer requires engraftment of antitumor T lymphocytes that not only retain specificity and function in vivo but also display an intrinsic capacity to survive. To date, adoptively transferred antitumor CD8(+) T lymphocytes (CTLs) have had limited life spans unless the host has been manipulated. To generate CTLs that have an intrinsic capacity to persist in vivo, we developed a human artificial antigen-presenting cell system that can educate antitumor CTLs to acquire both a central memory and an effector memory phenotype as well as the capacity to survive in culture for prolonged periods of time. We examined whether antitumor CTLs generated using this system could function and persist in patients. We showed that MART1-specific CTLs, educated and expanded using our artificial antigen-presenting cell system, could survive for prolonged periods in advanced-stage melanoma patients without previous conditioning or cytokine treatment. Moreover, these CTLs trafficked to the tumor, mediated biological and clinical responses, and established antitumor immunologic memory. Therefore, this approach may broaden the availability of adoptive cell therapy to patients both alone and in combination with other therapeutic modalities.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Memória Imunológica/imunologia , Melanoma/imunologia , Transferência Adotiva , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/uso terapêutico , Células Apresentadoras de Antígenos/efeitos dos fármacos , Células Apresentadoras de Antígenos/imunologia , Antígenos CD/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Antígeno CTLA-4 , Movimento Celular/efeitos dos fármacos , Epitopos/imunologia , Feminino , Humanos , Tolerância Imunológica/efeitos dos fármacos , Tolerância Imunológica/imunologia , Memória Imunológica/efeitos dos fármacos , Interleucina-15/administração & dosagem , Interleucina-15/farmacologia , Interleucina-2/administração & dosagem , Interleucina-2/farmacologia , Antígeno MART-1/imunologia , Masculino , Melanoma/tratamento farmacológico , Pessoa de Meia-Idade , Fenótipo , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/transplante , Fatores de Tempo
4.
Clin Cancer Res ; 14(19): 6125-36, 2008 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-18829491

RESUMO

PURPOSE: Interleukin 21 (IL-21) is a promising new cytokine, which is undergoing clinical testing as an anticancer agent. Although IL-21 provides potent stimulation of CD8(+) T cells, it has also been suggested that IL-21 is immunosuppressive by counteracting the maturation of dendritic cells. The dissociation of these two opposing effects may enhance the utility of IL-21 as an immunotherapeutic. In this study, we used a cell-based artificial antigen-presenting cell (aAPC) lacking a functional IL-21 receptor (IL-21R) to investigate the immunostimulatory properties of IL-21. EXPERIMENTAL DESIGN: The immunosuppressive activity of IL-21 was studied using human IL-21R(+) dendritic cells. Antigen-specific CD8(+) T cells stimulated with human cell-based IL-21R(-)aAPC were used to isolate the T-cell immunostimulatory effects of IL-21. The functional outcomes, including phenotype, cytokine production, proliferation, and cytotoxicity were evaluated. RESULTS: IL-21 limits the immune response by maintaining immunologically immature dendritic cells. However, stimulation of CD8(+) T cells with IL-21R(-) aAPC, which secrete IL-21, results in significant expansion. Although priming in the presence of IL-21 temporarily modulated the T-cell phenotype, chronic stimulation abrogated these differences. Importantly, exposure to IL-21 during restimulation promoted the enrichment and expansion of antigen-specific CD8(+) T cells that maintained IL-2 secretion and gained enhanced IFN-gamma secretion. Tumor antigen-specific CTL generated in the presence of IL-21 recognized tumor cells efficiently, demonstrating potent effector functions. CONCLUSIONS: IL-21 induces opposing effects on antigen-presenting cells and CD8(+) T cells. Strategic application of IL-21 is required to induce optimal clinical effects and may enable the generation of large numbers of highly avid tumor-specific CTL for adoptive immunotherapy.


Assuntos
Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/citologia , Interleucinas/metabolismo , Receptores de Interleucina-21/metabolismo , Células Apresentadoras de Antígenos/metabolismo , Proliferação de Células , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Antígenos de Histocompatibilidade Classe I/química , Humanos , Imunoterapia Adotiva/métodos , Fenótipo , Receptores de Interleucina-21/genética , Linfócitos T/imunologia , Fatores de Tempo , Resultado do Tratamento
5.
Clin Cancer Res ; 13(6): 1857-67, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-17363542

RESUMO

PURPOSE: Antitumor lymphocytes can be generated ex vivo unencumbered by immunoregulation found in vivo. Adoptive transfer of these cells is a promising therapeutic modality that could establish long-term antitumor immunity. However, the widespread use of adoptive therapy has been hampered by the difficulty of consistently generating potent antitumor lymphocytes in a timely manner for every patient. To overcome this, we sought to establish a clinical grade culture system that can reproducibly generate antigen-specific cytotoxic T lymphocytes (CTL). EXPERIMENTAL DESIGN: We created an off-the-shelf, standardized, and renewable artificial antigen-presenting cell (aAPC) line that coexpresses HLA class I, CD54, CD58, CD80, and the dendritic cell maturation marker CD83. We tested the ability of aAPC to generate tumor antigen-specific CTL under optimal culture conditions. The number, phenotype, effector function, and in vitro longevity of generated CTL were determined. RESULTS: Stimulation of CD8(+) T cells with peptide-pulsed aAPC generated large numbers of functional CTL that recognized a variety of tumor antigens. These CTLs, which possess a phenotype consistent with in vivo persistence, survived ex vivo for prolonged periods of time. Clinical grade aAPC(33), produced under current Good Manufacturing Practices guidelines, generated sufficient numbers of CTL within a short period of time. These CTL specifically lysed a variety of melanoma tumor lines naturally expressing a target melanoma antigen. Furthermore, antitumor CTL were easily generated in all melanoma patients examined. CONCLUSIONS: With clinical grade aAPC(33) in hand, we are now poised for clinical translation of ex vivo generated antitumor CTL for adoptive cell transfer.


Assuntos
Células Apresentadoras de Antígenos/transplante , Biomimética/métodos , Linfócitos T CD8-Positivos/transplante , Imunoterapia Adotiva , Melanoma/terapia , Apresentação de Antígeno/imunologia , Células Apresentadoras de Antígenos/imunologia , Antígenos de Neoplasias/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células/efeitos dos fármacos , Meia-Vida , Humanos , Interferon gama/metabolismo , Interleucina-15/farmacologia , Células K562 , Antígeno MART-1 , Melanoma/imunologia , Melanoma/metabolismo , Melanoma/patologia , Proteínas de Neoplasias/metabolismo , Células Tumorais Cultivadas
6.
Blood ; 108(8): 2662-8, 2006 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-16778141

RESUMO

Juvenile myelomonocytic leukemia (JMML) is a rare clonal myeloproliferative disorder. Although allogeneic stem cell transplantation can induce long-term remissions, relapse rates remain high and innovative approaches are needed. Since donor lymphocyte infusions have clinical activity in JMML, T-cell-mediated immunotherapy could provide a nonredundant treatment approach to compliment current therapies. Gamma-globin, an oncofetal protein overexpressed by clonogenic JMML cells, may serve as a target of an antitumor immune response. We predicted 5 gamma-globin-derived peptides as potential human leukocyte antigen (HLA)-A2 restricted cytotoxic T lymphocyte (CTL) epitopes and showed that 4 (g031, g071, g105, and g106) bind A2 molecules in vitro. Using an artificial antigen-presenting cell (aAPC) that can process both the N- and C-termini of endogenously expressed proteins, we biochemically confirmed that g105 is naturally processed and presented by cell surface A2. Furthermore, g105-specific CD8(+) CTLs generated from A2-positive healthy donors were able to specifically cytolyze gamma-globin(+), but not gamma-globin(-) JMML cells in an A2-restricted manner. These results suggest that this aAPC-based approach enables the biochemical identification of CD8(+) T-cell epitopes that are processed and presented by intact cells, and that CTL immunotherapy of JMML could be directed against the gamma-globin-derived epitope g105.


Assuntos
Antígenos de Neoplasias/isolamento & purificação , Linfócitos T CD8-Positivos/imunologia , Globinas/imunologia , Leucemia Mielomonocítica Aguda/imunologia , Células Apresentadoras de Antígenos/imunologia , Antígenos de Neoplasias/genética , Criança , Epitopos/isolamento & purificação , Antígeno HLA-A2/metabolismo , Humanos , Técnicas In Vitro , Leucemia Mielomonocítica Aguda/genética
7.
Clin Cancer Res ; 12(10): 2967-75, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16707591

RESUMO

Appropriate presentation of tumor-associated antigens (TAA) by antigen-presenting cells (APC) is required for the development of clinically relevant antitumor T-cell responses. One common approach, which uses APC pulsed with synthetic peptides, can sometimes generate ineffective immune responses. This failure may, in part, be attributed to the formation of HLA/synthetic pulsed peptide complexes that possess different conformations compared with those of endogenously presented peptides. In addition, endogenous peptides may undergo post-translational modifications, which do not occur with synthetic peptides. Because our goal is to induce immunity that can recognize TAA that are endogenously presented by tumors, we designed an APC that would not only express the required immunoaccessory molecules but also naturally process and present target antigenic peptides. In this study, we generated an artificial APC (aAPC) that can endogenously present any chosen HLA-A*0201 (A2)-restricted peptide by processing a fusion protein that contains a unique "LTK" sequence linked to the antigenic peptide. Proteasome-dependent processing is so effective that the presented peptide can be directly eluted from the cell surface and identified by biochemical methods. Furthermore, we found that aAPC, engineered to endogenously present peptide derived from the melanoma antigen MART1, can be used to prime and expand antitumor CTL that target MART1-expressing tumor cells in a HLA-A2-restricted manner. Our engineered aAPC could serve as an "off-the-shelf" APC designed to constitutively express class I-restricted TAA peptides and could be used to generate effective T-cell responses to treat human disease.


Assuntos
Apresentação de Antígeno , Células Apresentadoras de Antígenos/imunologia , Antígenos HLA-A/imunologia , Antígenos de Neoplasias , Antígeno HLA-A2 , Humanos , Imunoterapia/métodos , Antígeno MART-1 , Proteínas de Neoplasias/imunologia , Neoplasias/imunologia , Neoplasias/terapia , Fragmentos de Peptídeos , Proteínas da Gravidez/imunologia , Linfócitos T Citotóxicos/imunologia
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