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1.
Langmuir ; 39(49): 17563-17567, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38084390
4.
PLoS Pathog ; 19(1): e1010351, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36689486

RESUMO

CMV, a ubiquitous herpesvirus, elicits an extraordinarily large T cell response that is sustained or increases over time, a phenomenon termed 'memory inflation.' Remarkably, even latent, non-productive infection can drive memory inflation. Despite intense research on this phenomenon, the infected cell type(s) involved are unknown. To identify the responsible cell type(s), we designed a Cre-lox murine CMV (MCMV) system, where a spread-deficient (ΔgL) virus expresses recombinant SIINFEKL only in Cre+ host cells. We found that latent infection of endothelial cells (ECs), but not dendritic cells (DCs) or hepatocytes, was sufficient to drive CD8 T cell memory inflation. Infection of Lyve-1-Cre and Prox1-CreERT2 mice revealed that amongst EC subsets, infection of lymphatic ECs was sufficient. Genetic ablation of ß2m on lymphatic ECs did not prevent inflation, suggesting another unidentified cell type can also present antigen to CD8 T cells during latency. This novel system definitively shows that antigen presentation by lymphatic ECs drives robust CD8 T cell memory inflation.


Assuntos
Infecções por Citomegalovirus , Infecção Latente , Muromegalovirus , Animais , Camundongos , Células Endoteliais , Linfócitos T CD8-Positivos , Antígenos , Memória Imunológica
5.
J Acoust Soc Am ; 152(6): 3809, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36586831

RESUMO

The ice-covered Arctic Ocean constitutes a unique underwater acoustic waveguide; it is a half-channel, upward refracting environment possessing a rough upper boundary consisting of sea ice of varying thickness. The sea ice itself is an acoustic waveguide, capable of supporting the propagation of compressional and shear waves. In particular, the ice supports compressional wave resonances created by impulsive forces on the upper surface of the ice. During ICEX20 and ICEX22, observations were made of compressional wave resonances excited by hammer drops, as well as by near-impulsive signals generated from the compression of dry snow underfoot while walking on the ice. Results demonstrate that ice thickness can be inferred from compressional wave resonances in the sea ice waveguide using signals generated by walking on the snow-covered ice. Inferred ice thickness estimates were consistent with observations made by magnetic induction and physical measurements in holes drilled through the ice. Average first- and multi-year ice thicknesses were inferred to be 1.1-1.3 m and 2.4-2.5 m, respectively.

6.
J Chem Educ ; 99(1): 417-427, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36186731

RESUMO

This study examines the use of individual development plans (IDPs) in a structured mentoring program as an effective mechanism for reducing identity-related anxiety for underrepresented trainees and increasing their learner agency. Social cognitive theory served to provide the theoretical framework for our implementation of IDPs and our investigation of the effects of completing IDPs on trainees attaining academic goals and subsequent success in enrolling in competitive PhD programs. Results suggest that IDPs are also an effective tool that can allow faculty mentors to provide the social support necessary for trainees to persist in accomplishing their short- and long-term learning goals. Additionally, trainee self-agency, in the use of the IDP and mentoring, seemed to provide an alternative narrative to ability as a sole predictor of STEM achievement. We also found that IDPs helped foster social support networks, providing stability, predictability, and a sense of belonging. Specifically, IDPs helped foster the emotional and informational support necessary for trainees to persist, despite obstacles, as they strived to attain their learning goals.

7.
J Immunol ; 207(10): 2534-2544, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34625521

RESUMO

Human CMV (HCMV) is a ubiquitous pathogen that indelibly shapes the NK cell repertoire. Using transcriptomic, epigenomic, and proteomic approaches to evaluate peripheral blood NK cells from healthy human volunteers, we find that prior HCMV infection promotes NK cells with a T cell-like gene profile, including the canonical markers CD3ε, CD5, and CD8ß, as well as the T cell lineage-commitment transcription factor Bcl11b. Although Bcl11b expression is upregulated during NK maturation from CD56bright to CD56dim, we find a Bcl11b-mediated signature at the protein level for FcεRIγ, PLZF, IL-2Rß, CD3γ, CD3δ, and CD3ε in later-stage, HCMV-induced NK cells. BCL11B is targeted by Notch signaling in T cell development, and culture of NK cells with Notch ligand increases cytoplasmic CD3ε expression. The Bcl11b-mediated gain of CD3ε, physically associated with CD16 signaling molecules Lck and CD247 in NK cells is correlated with increased Ab-dependent effector function, including against HCMV-infected cells, identifying a potential mechanism for their prevalence in HCMV-infected individuals and their prospective clinical use in Ab-based therapies.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/imunologia , Infecções por Citomegalovirus/imunologia , Células Matadoras Naturais/imunologia , Subpopulações de Linfócitos/imunologia , Proteínas Repressoras/imunologia , Proteínas Supressoras de Tumor/imunologia , Animais , Complexo CD3/imunologia , Humanos , Camundongos , Camundongos Transgênicos , Transcriptoma
8.
ACS Cent Sci ; 7(3): 383-391, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33791420

RESUMO

We present a model for STEM organizations to write catalytic diversity, inclusion, respect, and equity (DIRE) policy statements as structured steps for sustained action.

9.
J Chem Health Saf ; 28(2): 103-111, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33824687

RESUMO

Chemistry practitioners, particularly in educational settings, often associate building strong safety cultures with compliance or regulatory requirements around laboratory glass-ware, equipment, flammable and incompatible materials, signage, container labels, and safety data sheets. Other fields of science also emphasize biohazardous materials, animal handling, human subject, and ergonomics. However, little attention in the literature has gone toward describing the interpersonal interactions and behaviors affecting the physical and emotional safety and wellbeing of laboratory trainees and personnel from marginalized backgrounds. This work unifies known approaches of building strong safety cultures and principles for preventing identity cues that threaten safety within a laboratory environment. Specifically, this work uses the four principles of chemical safety RAMP model as a conceptual framework for integrating identity safety within the laboratory safety culture.

10.
Eur J Immunol ; 51(6): 1473-1481, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33684223

RESUMO

Therapeutic antibodies blocking PD-1-/PD-L1 interaction have achieved remarkable clinical success in cancer. In addition to blocking a target molecule, some isotypes of antibodies can activate complement, NK cells or phagocytes, resulting in death of the cell expressing the antibody's target. Human anti-PD-1 therapeutics use antibody isotypes designed to minimize such antibody-dependent lysis. In contrast, anti-PD-1 reagents used in mice are derived from multiple species, with different isotypes, and are not engineered to reduce target cell death: few studies analyze or discuss how antibody species and isotype may impact data interpretation. We demonstrate here that anti-PD-1 therapy to promote activation and proliferation of murine PD-1-expressing CD8 T cells sometimes led instead to a loss of antigen specific cells. This phenomenon was seen in two tumor models and a model of virus infection, and varied with the clone of anti-PD-1 antibody. Additionally, we compared competition among anti-PD-1 clones to find a combination that allows detection of PD-1-expressing cells despite the presence of blocking anti-PD1 antibodies in vivo. These data bring attention to the possibility of unintended target cell depletion with some commonly used anti-mouse PD-1 clones, and should provide a valuable resource for the design and interpretation of anti-PD-1 studies in mice.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por Herpesviridae/imunologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia/métodos , Muromegalovirus/fisiologia , Sarcoma/imunologia , Neoplasias Cutâneas/imunologia , Animais , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/transplante , Morte Celular , Linhagem Celular Tumoral , Cricetinae , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Infecções por Herpesviridae/terapia , Humanos , Imunoglobulina G/metabolismo , Isotipos de Imunoglobulinas/metabolismo , Metilcolantreno , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Ratos , Sarcoma/terapia , Neoplasias Cutâneas/terapia
11.
MAbs ; 12(1): 1834818, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33151105

RESUMO

Simulating a viral infection in tumor cells is an attractive concept to eliminate tumor cells. We previously reported the molecular design and the in vitro potency of recombinant monoclonal antibodies fused to a virus-derived peptide MHC class I complex that bypass the peptide processing and MHC loading pathway and directly displays a viral peptide in an MHC class I complex on the tumor cell surface. Here, we show that a vaccination-induced single peptide-specific CD8 T cell response was sufficient to eliminate B16 melanoma tumor cells in vivo in a fully immunocompetent, syngeneic mouse tumor model when mice were treated with mouse pMHCI-IgGs fusion proteins targeting the mouse fibroblast activation protein. Tumor growth of small, established B16 lung metastases could be controlled. The pMHCI-IgG had similar potency as an analogous pan-CD3 T-cell bispecific antibody. In contrast to growth control of small tumors, none of the compounds controlled larger solid tumors of MC38 cancer cells, despite penetration of pMHCI-IgGs into the tumor tissue and clear attraction and activation of antigen-specific CD8 T cells inside the tumor. pMHCI-IgG can have a similar potency as classical pan-T-cell recruiting molecules. The results also highlight the need to better understand immune suppression in advanced solid tumors.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Imunoglobulina G/imunologia , Melanoma Experimental/imunologia , Animais , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes de Fusão/imunologia
12.
Glob Health Action ; 13(1): 1831794, 2020 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-33086945

RESUMO

BACKGROUND: Global demand for capacity building has increased interest for eLearning. As eLearning resources become more common, effective implementation is required to scale up utilization in Low- and Middle-Income Countries (LMICs). OBJECTIVE: This paper describes the process of implementing a malnutrition eLearning course, effectiveness of course delivery models devised, factors affecting course completion, and cost comparison between the models and face-to-face training at healthcare and academic institutions in Ghana. METHODS: Four delivery models: Mobile Training Centre (MTC), Online Delivery (OD), Institutional Computer Workstation (ICW) and Mixed Delivery (MD) - a combination of OD and ICW - were determined. Participants were enabled to access the course using one of the four models where contextually appropriate. Pre and post-assessments and questionnaires were administered to compare participants' course completion status and knowledge gain between delivery models. The effect of access to computer and Internet at home and relevance of course to job and academic progression on course completion were further investigated. Comparison of delivery model costs against face-to-face training was also undertaken. RESULTS: Of 7 academic and 9 healthcare institutions involving 915 people, 9 used MTC (34.8%), 3 OD (18.8%), 3 ICW (34.2%) and 1 MD (12.2%). Course completion was higher among institutions where the course was relevant to job or implemented as part of required curriculum activities. Knowledge gain was significant among most participants, but higher among those who found the course relevant to job or academic progression. The implementation costs per participant for training with MTC were £51.0, OD £2.2, ICW £1.2 and MD £1.1, compared with a face-to-face training estimate of £105.0 (1 GHS = 0.14 GBP). CONCLUSION: The malnutrition eLearning course makes global capacity building in malnutrition management achievable. Adopting contextually appropriate delivery models and ensuring training is relevant to job/academic progression can enhance eLearning effectiveness in LMICs.


Assuntos
Países em Desenvolvimento , Educação a Distância/organização & administração , Pessoal de Saúde/educação , Capacitação em Serviço/organização & administração , Desnutrição/epidemiologia , Fortalecimento Institucional/organização & administração , Currículo , Gana , Humanos , Aprendizagem , Estudos Longitudinais , Estudos Prospectivos
13.
Int J Mol Sci ; 21(7)2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32230859

RESUMO

Studies have suggested that type 2 diabetes (T2D) is associated with a higher incidence of breast cancer and related mortality rates. T2D postmenopausal women have an ~20% increased chance of developing breast cancer, and women with T2D and breast cancer have a 50% increase in mortality compared to breast cancer patients without diabetes. This correlation has been attributed to the general activation of insulin receptor signaling, glucose metabolism, phosphatidylinositol (PI) kinases, and growth pathways. Furthermore, the presence of breast cancer specific PI kinase and/or phosphatase mutations enhance metastatic breast cancer phenotypes. We hypothesized that each of the breast cancer subtypes may have characteristic PI phosphorylation profiles that are changed in T2D conditions. Therefore, we sought to characterize the PI phosphorylation when equilibrated in normal glycemic versus hyperglycemic serum conditions. Our results suggest that hyperglycemia leads to: 1) A reduction in PI3P and PIP3, with increased PI4P that is later converted to PI(3,4)P2 at the cell surface in hormone receptor positive breast cancer; 2) a reduction in PI3P and PI4P with increased PIP3 surface expression in human epidermal growth factor receptor 2-positive (HER2+) breast cancer; and 3) an increase in di- and tri-phosphorylated PIs due to turnover of PI3P in triple negative breast cancer. This study begins to describe some of the crucial changes in PIs that play a role in T2D related breast cancer incidence and metastasis.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/metabolismo , Hiperglicemia/metabolismo , Fosfatidilinositóis/metabolismo , Mama/patologia , Neoplasias da Mama/complicações , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Glucose/metabolismo , Humanos , Hiperglicemia/complicações , Células MCF-7 , Fosforilação , Fosfotransferases (Aceptor do Grupo Álcool) , Receptor ErbB-2/metabolismo , Receptor de Insulina , Transdução de Sinais
14.
J Immunol ; 204(1): 112-121, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31818981

RESUMO

CMV is an obligate and persistent intracellular pathogen that continually drives the production of highly differentiated virus-specific CD8+ T cells in an Ag-dependent manner, a phenomenon known as memory inflation. Extensive proliferation is required to generate and maintain inflationary CD8+ T cell populations, which are counterintuitively short-lived and typically exposed to limited amounts of Ag during the chronic phase of infection. An apparent discrepancy therefore exists between the magnitude of expansion and the requirement for ongoing immunogenic stimulation. To address this issue, we explored the clonal dynamics of memory inflation. First, we tracked congenically marked OT-I cell populations in recipient mice infected with murine CMV (MCMV) expressing the cognate Ag OVA. Irrespective of numerical dominance, stochastic expansions were observed in each population, such that dominant and subdominant OT-I cells were maintained at stable frequencies over time. Second, we characterized endogenous CD8+ T cell populations specific for two classic inflationary epitopes, M38 and IE3. Multiple clonotypes simultaneously underwent Ag-driven proliferation during latent infection with MCMV. In addition, the corresponding CD8+ T cell repertoires were stable over time and dominated by persistent clonotypes, many of which also occurred in more than one mouse. Collectively, these data suggest that stochastic encounters with Ag occur frequently enough to maintain oligoclonal populations of inflationary CD8+ T cells, despite intrinsic constraints on epitope display at individual sites of infection with MCMV.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Seleção Clonal Mediada por Antígeno/imunologia , Memória Imunológica/imunologia , Muromegalovirus/imunologia , Animais , Proliferação de Células , Epitopos/imunologia , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ovalbumina/imunologia
16.
ACS Omega ; 4(4): 6726-6736, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31179409

RESUMO

The family of Angiomotin (Amot) proteins regulate several biological pathways associated with cellular differentiation, proliferation, and migration. These adaptor proteins target proteins to the apical membrane, actin fibers, or the nucleus. A major function of the Amot coiled-coil homology (ACCH) domain is to initiate protein interactions with the cellular membrane, particularly those containing phosphatidylinositol lipids. The work presented in this article uses several ACCH domain lysine/arginine mutants to probe the relative importance of individual residues for lipid binding. This identified four lysine and three arginine residues that mediate full lipid binding. Based on these findings, three of these residues were mutated to glutamates in the Angiomotin 80 kDa splice form and were incorporated into human mammary cell lines. Results show that mutating three of these residues in the context of full-length Angiomotin reduced the residence of the protein at the apical membrane. These findings provide new insight into how the ACCH domain mediates lipid binding to enable Amot proteins to control epithelial cell growth.

17.
BMC Med Res Methodol ; 18(1): 136, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30445914

RESUMO

BACKGROUND: Increasingly, collaborative participatory methods requiring open and honest interaction between a range of stakeholders are being used to improve health service delivery. To be successful these methodologies must incorporate perspectives from a range of patients and staff. Yet, if unaccounted for, the complex relationships amongst staff groups and between patients and providers can affect the veracity and applicability of co-designed solutions. METHODS: Two focus groups convened to discuss suggestions for the improvement of blood testing and result communication in primary care. The groups were mixed of patients and staff in various combinations drawn from the four participating study practices. Here we present a secondary mixed-method analysis of the interaction between participants in both groups using sociogrammatic and thematic analysis. RESULTS: Despite a similar mix of practice staff and patients the two groups produced contrasting discussions, seemingly influenced by status and social context. The sociograms provided a useful insight into the flow of conversation and highlighted the dominance of the senior staff member in the first focus group. Within the three key themes of social context, the alliances formed between participants and the fluidity of the roles assumed manifested differently between groups apparently dictated by the different profile of the participants of each. CONCLUSIONS: For primary care service improvement attention must be paid to the background of participants when convening collaborative service improvement groups as status and imported hierarchies can have significant connotations for the data produced.


Assuntos
Comunicação , Comportamento Cooperativo , Grupos Focais , Serviços de Saúde/normas , Melhoria de Qualidade/normas , Qualidade da Assistência à Saúde/normas , Atenção à Saúde/métodos , Atenção à Saúde/normas , Testes Hematológicos/métodos , Testes Hematológicos/normas , Humanos , Relações Médico-Paciente , Atenção Primária à Saúde/organização & administração , Atenção Primária à Saúde/normas , Melhoria de Qualidade/organização & administração , Qualidade da Assistência à Saúde/organização & administração , Reino Unido
18.
J Phys Chem B ; 122(35): 8404-8415, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-29877706

RESUMO

Phosphatidylinositol (PI) lipids are necessary for many cellular signaling pathways of membrane associated proteins, such as angiomotin (Amot). The Amot family regulates cellular polarity, growth, and migration. Given the low concentration of PI lipids in these membranes, it is likely that such protein-membrane interactions are stabilized by lipid domains or small lipid clusters. By small-angle X-ray scattering, we show that nonphosphorylated PI lipids induce lipid demixing in ternary mixtures of phosphatidylcholine (PC) and phosphatidylethanolamine (PE), likely because of preferential interactions between the head groups of PE and PI. These results were obtained in the presence of buffer containing tris(hydroxymethyl)aminomethane, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, NaCl, ethylenediaminetetraacetic acid, dithiothreitol, and benzamidine at pH 8.0 that in previous work showed an ability to cause PC to phase separate but are necessary to stabilize Amot for in vitro experimentation. Collectively, this provided a framework for determining the effect of Amot on lipid organization. Using fluorescence spectroscopy, we were able to show that the association of Amot with this lipid platform causes significant reorganization of the lipid into a more homogenous structure. This reorganization mechanism could be the basis for Amot membrane association and fusogenic activity previously described in the literature and should be taken into consideration in future protein-membrane interaction studies.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/química , Lipossomos/química , Proteínas de Membrana/química , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Fosfatidilinositóis/química , Escherichia coli/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas de Membrana/genética , Domínios Proteicos , Espalhamento a Baixo Ângulo , Temperatura , Difração de Raios X
19.
Curr Opin Virol ; 28: 161-166, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29459261

RESUMO

The immune response to CMV is characterized by extremely large T cell and antibody responses that persist for a lifetime, but do not prevent superinfection with other CMV strains. This makes generation of a vaccine against CMV very difficult, but has facilitated development of CMV-vectored vaccines, which have shown promise in mouse tumor models and in monkey models of infectious disease. The serendipitous use of a mutant rhesus CMV vector for the SIV vaccine elicited extraordinary, CD8 T cell responses restricted by MHCII and non-classical MHCI molecules which apparently provide protection against SIV. CMV-specific CD8 T cell responses in the mouse model are driven by antigen and live out their lives primarily within the intravascular compartment.


Assuntos
Anticorpos Antivirais/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Citomegalovirus/imunologia , Linfócitos T/imunologia , Animais , Vacinas Anticâncer/imunologia , Modelos Animais de Doenças , Vetores Genéticos , Humanos , Macaca mulatta , Camundongos , Modelos Animais , Neoplasias/imunologia , Neoplasias/virologia , Vacinação
20.
Indiana Univ J Undergrad Res ; 4(1): 17-26, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30906876

RESUMO

Epidemiological studies have proposed a link between type II diabetes and cancer via the IGF/insulin signaling pathway, which includes insulin-like peptides (IGF1, IGF2, and insulin), insulin receptors (IR-A, IR-B, IGF1R, and hybrids), and insulin substrate proteins (IRS1-6). In this study, up- and down-regulation of various components in the IGF/insulin signaling pathway are compared to clinical outcomes for cancer patients; the components include diagnosis age, overall survival, tumor invasion and vascularization, and body mass index. It was found that the up-regulation of insulin growth Factor (IGF)/insulin components was associated with overall survival and tumor invasion and vascularization, while the down-regulation of equivalent components was not associated with clinical outcomes assessed in this study. Particularly, the up-regulation of DOK5, IGF2, and IRS2 in colorectal cancer and IGF1R in liver cancer is associated with significantly decreased overall survival. Functional aberrations in either of the two proteins in co-expression pairs were identified for each cancer and correlated with overall survival and diagnosis age. Specific biomarkers proposed in this study will be further analyzed to fine-tune consistent associations that can be translated to reliable prognostic standards for the roles of IGF/insulin signaling pathway modulations that promote cancer.

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