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1.
Immunity ; 45(2): 358-73, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27496729

RESUMO

Dynamic reprogramming of metabolism is essential for T cell effector function and memory formation. However, the regulation of metabolism in exhausted CD8(+) T (Tex) cells is poorly understood. We found that during the first week of chronic lymphocytic choriomeningitis virus (LCMV) infection, before severe dysfunction develops, virus-specific CD8(+) T cells were already unable to match the bioenergetics of effector T cells generated during acute infection. Suppression of T cell bioenergetics involved restricted glucose uptake and use, despite persisting mechanistic target of rapamycin (mTOR) signaling and upregulation of many anabolic pathways. PD-1 regulated early glycolytic and mitochondrial alterations and repressed transcriptional coactivator PGC-1α. Improving bioenergetics by overexpression of PGC-1α enhanced function in developing Tex cells. Therapeutic reinvigoration by anti-PD-L1 reprogrammed metabolism in a subset of Tex cells. These data highlight a key metabolic control event early in exhaustion and suggest that manipulating glycolytic and mitochondrial metabolism might enhance checkpoint blockade outcomes.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Animais , Anticorpos Neutralizantes/farmacologia , Antígeno B7-H1/imunologia , Células Cultivadas , Reprogramação Celular , Senescência Celular , Metabolismo Energético , Glucose/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Receptor de Morte Celular Programada 1/genética , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
2.
Nat Immunol ; 10(12): 1283-91, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19898472

RESUMO

To identify genes and mechanisms involved in humoral immunity, we did a mouse genetic screen for mutations that do not affect the first wave of antibody to immunization but disrupt response maturation and persistence. The first two mutants identified had loss-of-function mutations in the gene encoding a previously obscure member of a family of Rho-Rac GTP-exchange factors, DOCK8. DOCK8-mutant B cells were unable to form marginal zone B cells or to persist in germinal centers and undergo affinity maturation. Dock8 mutations disrupted accumulation of the integrin ligand ICAM-1 in the B cell immunological synapse but did not alter other aspects of B cell antigen receptor signaling. Humoral immunodeficiency due to Dock8 mutation provides evidence that organization of the immunological synapse is critical for signaling the survival of B cell subsets required for long-lasting immunity.


Assuntos
Formação de Anticorpos , Linfócitos B/imunologia , Centro Germinativo/imunologia , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/imunologia , Mutação , Sinapses/imunologia , Sequência de Aminoácidos , Animais , Linfócitos B/metabolismo , Sequência de Bases , Centro Germinativo/metabolismo , Fatores de Troca do Nucleotídeo Guanina/química , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Quaternária de Proteína , Alinhamento de Sequência
3.
Nat Immunol ; 10(8): 831-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19597497

RESUMO

T cell antigen receptor (TCR) signaling in CD4(+)CD8(+) double-positive thymocytes determines cell survival and lineage commitment, but the genetic and molecular basis of this process is poorly defined. To address this issue, we used ethylnitrosourea mutagenesis to identify a previously unknown T lineage-specific gene, Themis, which is critical for the completion of positive selection. Themis contains a tandem repeat of a unique globular domain (called 'CABIT' here) that includes a cysteine motif that defines a family of five uncharacterized vertebrate proteins with orthologs in most animal species. Themis-deficient thymocytes showed no substantial impairment in early TCR signaling but did show altered expression of genes involved in the cell cycle and survival before and during positive selection. Our data suggest a unique function for Themis in sustaining positive selection.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Linhagem da Célula/fisiologia , Proteínas/fisiologia , Receptores de Antígenos de Linfócitos T/fisiologia , Sequência de Aminoácidos , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Diferenciação Celular , Linhagem Celular , Sobrevivência Celular/fisiologia , Etilnitrosoureia/farmacologia , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Camundongos , Dados de Sequência Molecular , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas/genética , Proteínas/imunologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais
4.
J Immunol ; 192(8): 3607-17, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24646739

RESUMO

High-affinity class-switched Abs and memory B cells are products of the germinal center (GC). The CD4+ T cell help required for the development and maintenance of the GC is delivered by follicular Th cells (T(FH)), a CD4+ Th cell subset characterized by expression of Bcl-6 and secretion of IL-21. The cellular interactions that mediate differentiation of TFH and GC B cells remain an important area of investigation. We previously showed that MHC class II (MHCII)-dependent dendritic cell Ag presentation is sufficient for the differentiation of a T(FH) intermediate (termed pre-T(FH)), characterized by Bcl-6 expression but lacking IL-21 secretion. In this article, we examine the contributions of MHCII Ag presentation by B cells to T(FH) differentiation and GC responses in several contexts. B cells alone do not efficiently prime naive CD4+ T cells or induce T(FH) after protein immunization; however, during lymphocytic choriomeningitis virus infection, B cells induce T(FH) differentiation despite the lack of effector CD4+ T cell generation. Still, MHCII+ dendritic cells and B cells cooperate for optimal T(FH) and GC B cell differentiation in response to both model Ags and viral infection. This study highlights the roles for B cells in both CD4+ T cell priming and T(FH) differentiation, and demonstrates that different APC subsets work in tandem to mediate the GC response.


Assuntos
Apresentação de Antígeno/imunologia , Linfócitos B/imunologia , Diferenciação Celular/imunologia , Centro Germinativo/imunologia , Centro Germinativo/metabolismo , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Antígenos/imunologia , Linfócitos B/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular/genética , Células Dendríticas/imunologia , Antígenos H-2/genética , Antígenos H-2/imunologia , Antígenos H-2/metabolismo , Imunização , Camundongos , Camundongos Knockout , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Viroses/imunologia , Viroses/metabolismo
5.
J Adv Pract Oncol ; 15(4): 245-252, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-39301102

RESUMO

Many targeted therapies to treat genetic mutations in non-small cell lung cancer (NSCLC) have been developed. Amivantamab (Rybrevant), a bispecific antibody targeting the epidermal growth factor receptor (EGFR) and mesenchymal-epithelial transition factor, was approved by the US Food and Drug Administration in 2021 for the treatment of adult patients with locally advanced or metastatic NSCLC EGFR exon 20 insertions, whose disease progressed on or after platinum-based chemotherapy. Amivantamab is administered intravenously weekly for 4 weeks, then every 2 weeks starting at Week 5, as 1,050 mg (body weight [BW] < 80 kg) or 1,400 mg (BW ≥ 80 kg), with the first dose split over 2 days. Infusion-related reactions (IRRs) are common with amivantamab and may present as chills, dyspnea, nausea, chest discomfort, and vomiting. To aid in the prevention, diagnosis, and treatment of IRRs, we evaluated infusion duration, IRR timing, and IRR severity in this post hoc analysis of patients who received amivantamab in CHRYSALIS. Infusion duration decreased over time, with a median infusion time at Cycle 1 Day 1 (C1D1) of 4.70 hours (1,050 mg) and 5.08 hours (1,400 mg), decreasing to 2.20 and 2.25 hours, respectively, by C1D22. Of the 273 IRRs, 98% occurred on C1D1 or C1D2, with median onset and time to resolution of 60 minutes. Most IRRs occurred during the infusion, were low grade, and were manageable with intervention strategies or treatment modifications. Advanced practitioners are critical in preventing, diagnosing, and managing IRRs, including educating patients and families, accurately administering infusions, prescribing premedications, and closely monitoring for IRRs.

6.
Eur J Immunol ; 41(12): 3423-35, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21969276

RESUMO

Deficiency in the guanine nucleotide exchange factor dedicator of cytokinesis 8 (DOCK8) causes a human immunodeficiency syndrome associated with recurrent sinopulmonary and viral infections. We have recently identified a DOCK8-deficient mouse strain, carrying an ethylnitrosourea-induced splice-site mutation that shows a failure to mature a humoral immune response due to the loss of germinal centre B cells. In this study, we turned to T-cell immunity to investigate further the human immunodeficiency syndrome and its association with decreased peripheral CD4(+) and CD8(+) T cells. Characterisation of the DOCK8-deficient mouse revealed T-cell lymphopenia, with increased T-cell turnover and decreased survival. Egress of mature CD4(+) thymocytes was reduced with increased migration of these cells to the chemokine CXCL12. However, despite the two-fold reduction in peripheral naïve T cells, the DOCK8-deficient mice generated a normal primary CD8(+) immune response and were able to survive acute influenza virus infection. The limiting effect of DOCK8 was in the normal survival of CD8(+) memory T cells after infection. These findings help to explain why DOCK8-deficient patients are susceptible to recurrent infections and provide new insights into how T-cell memory is sustained.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Fatores de Troca do Nucleotídeo Guanina/deficiência , Fatores de Troca do Nucleotídeo Guanina/imunologia , Memória Imunológica/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Movimento Celular/imunologia , Sobrevivência Celular/imunologia , Células Cultivadas , Quimiocina CXCL12/imunologia , Humanos , Síndromes de Imunodeficiência/imunologia , Ativação Linfocitária/imunologia , Linfoma de Células T/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/imunologia
7.
Am Psychol ; 74(2): 259, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30762397

RESUMO

Presents an obituary for Carole A. Rayburn (1938-2017). A feminist, activist, therapist, and researcher, Rayburn authored or coauthored several copyrighted psychological inventories and dozens of book chapters and journal articles and wrote or edited at least nine books. On the national level, she was active in multiple divisions of the American Psychological Association (APA) and was elected to fellow status in at least 10 of them. Courageously speaking truth to power, Rayburn wrote clearly and directly about the oppression of women through misogynistic, sexist, and patriarchal attitudes and systems that permeate society. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

8.
Int J Nurs Knowl ; 24(1): 15-24, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23413930

RESUMO

PURPOSE: To reveal hidden patterns and knowledge present in nursing care information documented with standardized nursing terminologies on end-of-life (EOL) hospitalized patients. METHOD: 596 episodes of care that included pain as a problem on a patient's care plan were examined using statistical and data mining tools. The data were extracted from the Hands-On Automated Nursing Data System database of nursing care plan episodes (n = 40,747) coded with NANDA-I, Nursing Outcomes Classification, and Nursing Intervention Classification (NNN) terminologies. System episode data (episode = care plans updated at every hand-off on a patient while staying on a hospital unit) had been previously gathered in eight units located in four different healthcare facilities (total episodes = 40,747; EOL episodes = 1,425) over 2 years and anonymized prior to this analyses. RESULTS: Results show multiple discoveries, including EOL patients with hospital stays (<72 hr) are less likely (p < .005) to meet the pain relief goals compared with EOL patients with longer hospital stays. CONCLUSIONS: The study demonstrates some major benefits of systematically integrating NNN into electronic health records.


Assuntos
Tomada de Decisões Gerenciais , Armazenamento e Recuperação da Informação , Cuidados de Enfermagem , Planejamento de Assistência ao Paciente , Assistência Terminal , Automação
9.
Nat Med ; 18(6): 980-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22561687

RESUMO

T cell immunity can potentially eradicate malignant cells and lead to clinical remission in a minority of patients with cancer. In the majority of these individuals, however, there is a failure of the specific T cell receptor (TCR)­mediated immune recognition and activation process. Here we describe the engineering and characterization of new reagents termed immune-mobilizing monoclonal TCRs against cancer (ImmTACs). Four such ImmTACs, each comprising a distinct tumor-associated epitope-specific monoclonal TCR with picomolar affinity fused to a humanized cluster of differentiation 3 (CD3)-specific single-chain antibody fragment (scFv), effectively redirected T cells to kill cancer cells expressing extremely low surface epitope densities. Furthermore, these reagents potently suppressed tumor growth in vivo. Thus, ImmTACs overcome immune tolerance to cancer and represent a new approach to tumor immunotherapy.


Assuntos
Citotoxicidade Imunológica , Neoplasias Experimentais/terapia , Receptores de Antígenos de Linfócitos T/fisiologia , Animais , Linfócitos T CD8-Positivos/imunologia , Humanos , Memória Imunológica , Imunoterapia , Interferon gama/biossíntese , Ativação Linfocitária , Camundongos , Camundongos SCID , Neoplasias Experimentais/imunologia
10.
Protein Cell ; 1(12): 1118-27, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21213105

RESUMO

Using directed mutagenesis and phage display on a soluble fragment of the human immunoglobulin super-family receptor ILT2 (synonyms: LIR1, MIR7, CD85j), we have selected a range of mutants with binding affinities enhanced by up to 168,000-fold towards the conserved region of major histocompatibility complex (MHC) class I molecules. Produced in a dimeric form, either by chemical cross-linking with bivalent polyethylene glycol (PEG) derivatives or as a genetic fusion with human IgG Fc-fragment, the mutants exhibited a further increase in ligand-binding strength due to the avidity effect, with resident half-times (t(1/2)) on the surface of MHC I-positive cells of many hours. The novel compounds antagonized the interaction of CD8 co-receptor with MHC I in vitro without affecting the peptide-specific binding of T-cell receptors (TCRs). In both cytokine-release assays and cell-killing experiments the engineered receptors inhibited the activation of CD8(+) cytotoxic T lymphocytes (CTLs) in the presence of their target cells, with subnanomolar potency and in a dose-dependent manner. As a selective inhibitor of CD8(+) CTL responses, the engineered high affinity ILT2 receptor presents a new tool for studying the activation mechanism of different subsets of CTLs and could have potential for the development of novel autoimmunity therapies.


Assuntos
Antígenos CD/genética , Antígenos CD/farmacologia , Fatores Imunológicos/genética , Fatores Imunológicos/farmacologia , Ativação Linfocitária/imunologia , Receptores Imunológicos/genética , Sequência de Aminoácidos , Antígenos CD/química , Autoimunidade , Bioensaio , Linhagem Celular , Citotoxicidade Imunológica/genética , Citotoxicidade Imunológica/imunologia , Relação Dose-Resposta Imunológica , Humanos , Imunoglobulinas/imunologia , Imunoglobulinas/metabolismo , Fatores Imunológicos/química , Cinética , Receptor B1 de Leucócitos Semelhante a Imunoglobulina , Ativação Linfocitária/genética , Complexo Principal de Histocompatibilidade/genética , Complexo Principal de Histocompatibilidade/imunologia , Dados de Sequência Molecular , Terapia de Alvo Molecular , Mutagênese Sítio-Dirigida , Biblioteca de Peptídeos , Polietilenoglicóis , Ligação Proteica/genética , Ligação Proteica/imunologia , Receptores Imunológicos/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo
12.
Vaccine ; 27(24): 3195-200, 2009 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-19446191

RESUMO

Telephone interviews of health department personnel in six states and review of an immunization database from one state were conducted to assess human papillomavirus (HPV) vaccine availability, recommendations, cost, policies, and educational materials in health departments in seven Appalachian states. Most (99.1%) health departments (n=234) reported receiving patient requests for the HPV vaccine, and only two (1%) health departments reported that they did not provide the vaccine for patients. HPV vaccine supply was reported to not meet the demand in 10.5% (24/228) of health departments due to high costs. Level (state, region, county) at which policy about the HPV vaccine was determined, vaccine recommendations, costs, and available educational materials varied among states. This study documented variation in vaccine availability, recommendations, cost, policies, and educational materials in Appalachian health departments that could significantly affect vaccine distribution. Findings highlight the need for more comprehensive and consistent policies that maximize accessibility of the HPV vaccine to women, especially those in underserved areas.


Assuntos
Vacinas contra Papillomavirus/imunologia , Região dos Apalaches , Feminino , Política de Saúde , Humanos , Imunização , Vacinas contra Papillomavirus/economia
14.
J Ren Care ; 33(1): 41-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17695562

RESUMO

The discussion was initiated by a paper comparing the measurement of dialysis dose (Kt/V) and solute clearance using on-line ultra-violet absorbance, blood and dialysate urea and ionic dialysance by Uhlin et al (NDT 2006). Participants from 14 countries discussed the theory behind the UV absorbance technique and the potential for its use in routine practice, the correlation between Kt/V measured using different methods, the use of ionic dialysance and the optimisation of dose monitoring. The 'take-home' messages from the discussion were that UV-absorbance could help ensure the delivery of dialysis dose as it provides real time feedback on the effect interventions such as repositioning of needles. The technology is relatively inexpensive and requires no consumables but changes in the dialysis machine settings could lead to misleading measurements if not communicated to the UV monitor. Session-to-session variation in dialysis dose can be measured using on-line clearance monitoring. If it is already on the machine and costs nothing, why not use it? Alternatively, regular access recirculation checks and a record of the total blood volume processed at each session allow problems with delivered dialysis dose to be picked up between routine blood tests.


Assuntos
Soluções para Diálise/administração & dosagem , Soluções para Diálise/farmacocinética , Monitorização Fisiológica/instrumentação , Diálise Renal/instrumentação , Espectrofotometria Ultravioleta , Humanos , Monitorização Fisiológica/métodos , Diálise Renal/métodos
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