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1.
Kidney Int ; 105(2): 218-230, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38245210

RESUMO

Glomerular diseases are classified using a descriptive taxonomy that is not reflective of the heterogeneous underlying molecular drivers. This limits not only diagnostic and therapeutic patient management, but also impacts clinical trials evaluating targeted interventions. The Nephrotic Syndrome Study Network (NEPTUNE) is poised to address these challenges. The study has enrolled >850 pediatric and adult patients with proteinuric glomerular diseases who have contributed to deep clinical, histologic, genetic, and molecular profiles linked to long-term outcomes. The NEPTUNE Knowledge Network, comprising combined, multiscalar data sets, captures each participant's molecular disease processes at the time of kidney biopsy. In this editorial, we describe the design and implementation of NEPTUNE Match, which bridges a basic science discovery pipeline with targeted clinical trials. Noninvasive biomarkers have been developed for real-time pathway analyses. A Molecular Nephrology Board reviews the pathway maps together with clinical, laboratory, and histopathologic data assembled for each patient to compile a Match report that estimates the fit between the specific molecular disease pathway(s) identified in an individual patient and proposed clinical trials. The NEPTUNE Match report is communicated using established protocols to the patient and the attending nephrologist for use in their selection of available clinical trials. NEPTUNE Match represents the first application of precision medicine in nephrology with the aim of developing targeted therapies and providing the right medication for each patient with primary glomerular disease.


Assuntos
Nefropatias , Síndrome Nefrótica , Adulto , Criança , Humanos , Biomarcadores , Ensaios Clínicos como Assunto , Glomérulos Renais/patologia , Síndrome Nefrótica/diagnóstico , Síndrome Nefrótica/genética , Síndrome Nefrótica/terapia
2.
Sci Immunol ; 8(82): eadd8454, 2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-37083450

RESUMO

Our understanding of tissue-resident memory T (TRM) cell biology has been largely developed from acute infection models in which antigen is cleared and sterilizing immunity is achieved. Less is known about TRM cells in the context of chronic antigen persistence and inflammation. We investigated factors that underlie TRM maintenance in a kidney transplantation model in which TRM cells drive rejection. In contrast to acute infection, we found that TRM cells declined markedly in the absence of cognate antigen, antigen presentation, or antigen sensing by the T cells. Depletion of graft-infiltrating dendritic cells or interruption of antigen presentation after TRM cells were established was sufficient to disrupt TRM maintenance and reduce allograft pathology. Likewise, removal of IL-15 transpresentation or of the IL-15 receptor on T cells during TRM maintenance led to a decline in TRM cells, and IL-15 receptor blockade prevented chronic rejection. Therefore, antigen and IL-15 presented by dendritic cells play nonredundant key roles in CD8 TRM cell maintenance in settings of antigen persistence and inflammation. These findings provide insights that could lead to improved treatment of chronic transplant rejection and autoimmunity.


Assuntos
Linfócitos T CD8-Positivos , Interleucina-15 , Humanos , Antígenos , Inflamação , Células T de Memória
3.
Bioscience ; 71(7): 757-770, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34220360

RESUMO

Access to field experiences can increase participation of diverse groups in the environmental and natural resources (ENR) workforce. Despite a growing interest among the ENR community to attract and retain diverse students, minimal data exist on what factors undergraduate students prioritize when applying for field experiences. Using a nationwide survey of US undergraduate ENR students, we show that attracting most students to field experiences-especially racial or ethnic minority students-will require pay above minimum wage. However, the concurrent landscape of pay in ENR fell short of meeting many students' pay needs. Aside from pay, ENR students valued training in technical field skills and analytical or research skills, working with their desired study species or taxa, and working near school or family. Additional barriers beyond limited pay included incompatible schedules and noninclusive work environments. Our findings provide important insights for attracting a diverse workforce to this critical stage in career advancement for students in ENR.

4.
Sci Immunol ; 6(57)2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33741656

RESUMO

Tissue-resident memory T cells (TRM) contained at sites of previous infection provide local protection against reinfection. Whether they form and function in organ transplants where cognate antigen persists is unclear. This is a key question in transplantation as T cells are detected long term in allografts, but it is not known whether they are exhausted or are functional memory T cells. Using a mouse model of kidney transplantation, we showed that antigen-specific and polyclonal effector T cells differentiated in the graft into TRM and subsequently caused allograft rejection. TRM identity was established by surface phenotype, transcriptional profile, and inability to recirculate in parabiosis and retransplantation experiments. Graft TRM proliferated locally, produced interferon-γ upon restimulation, and their in vivo depletion attenuated rejection. The vast majority of antigen-specific and polyclonal TRM lacked phenotypic and transcriptional exhaustion markers. Single-cell analysis of graft T cells early and late after transplantation identified a transcriptional program associated with transition to the tissue-resident state that could serve as a platform for the discovery of therapeutic targets. Thus, recipient effector T cells differentiate into functional graft TRM that maintain rejection locally. Targeting these TRM could improve renal transplant outcomes.


Assuntos
Aloenxertos/imunologia , Antígenos/imunologia , Rejeição de Enxerto/imunologia , Memória Imunológica , Células T de Memória/imunologia , Aloenxertos/metabolismo , Aloenxertos/patologia , Animais , Biomarcadores , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Modelos Animais de Doenças , Rejeição de Enxerto/metabolismo , Rejeição de Enxerto/patologia , Imuno-Histoquímica , Imunofenotipagem , Transplante de Rim , Células T de Memória/metabolismo , Camundongos , Especificidade de Órgãos/genética , Especificidade de Órgãos/imunologia , Transplante de Órgãos/efeitos adversos , Transplante de Órgãos/métodos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia
5.
Science ; 368(6495): 1122-1127, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32381589

RESUMO

Immunological memory specific to previously encountered antigens is a cardinal feature of adaptive lymphoid cells. However, it is unknown whether innate myeloid cells retain memory of prior antigenic stimulation and respond to it more vigorously on subsequent encounters. In this work, we show that murine monocytes and macrophages acquire memory specific to major histocompatibility complex I (MHC-I) antigens, and we identify A-type paired immunoglobulin-like receptors (PIR-As) as the MHC-I receptors necessary for the memory response. We demonstrate that deleting PIR-A in the recipient or blocking PIR-A binding to donor MHC-I molecules blocks memory and attenuates kidney and heart allograft rejection. Thus, innate myeloid cells acquire alloantigen-specific memory that can be targeted to improve transplant outcomes.


Assuntos
Rejeição de Enxerto/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Imunidade Inata , Memória Imunológica , Macrófagos/imunologia , Monócitos/imunologia , Receptores Imunológicos/fisiologia , Animais , Deleção de Genes , Rejeição de Enxerto/genética , Transplante de Coração , Transplante de Rim , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Mutantes , Receptores Imunológicos/genética
6.
J Bacteriol ; 202(7)2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-31964698

RESUMO

Vibrio fischeri is a bacterial symbiont that colonizes the light organ of the Hawaiian bobtail squid, Euprymna scolopes Certain strains of V. fischeri express a type VI secretion system (T6SS), which delivers effectors into neighboring cells that result in their death. Strains that are susceptible to the T6SS fail to establish symbiosis with a T6SS-positive strain within the same location of the squid light organ, which is a phenomenon termed strain incompatibility. This study investigates the regulation of the T6SS in V. fischeri strain FQ-A001. Here, we report that the expression of Hcp, a necessary structural component of the T6SS, depends on the alternative sigma factor σ54 and the bacterial enhancer binding protein VasH. VasH is necessary for FQ-A001 to kill other strains, suggesting that VasH-dependent regulation is essential for the T6SS of V. fischeri to affect intercellular interactions. In addition, this study demonstrates VasH-dependent transcription of hcp within host-associated populations of FQ-A001, suggesting that the T6SS is expressed within the host environment. Together, these findings establish a model for transcriptional control of hcp in V. fischeri within the squid light organ, thereby increasing understanding of how the T6SS is regulated during symbiosis.IMPORTANCE Animals harbor bacterial symbionts with specific traits that promote host fitness. Mechanisms that facilitate intercellular interactions among bacterial symbionts impact which bacterial lineages ultimately establish symbiosis with the host. How these mechanisms are regulated is poorly characterized in nonhuman bacterial symbionts. This study establishes a model for the transcriptional regulation of a contact-dependent killing machine, thereby increasing understanding of mechanisms by which different strains compete while establishing symbiosis.


Assuntos
Aliivibrio fischeri/fisiologia , Proteínas de Bactérias/metabolismo , Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos , Simbiose , Sistemas de Secreção Tipo VI , Sequência de Bases , Regulação Bacteriana da Expressão Gênica
7.
J Clin Invest ; 130(1): 287-294, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31763998

RESUMO

Activation of host T cells that mediate allograft rejection is a 2-step process. The first occurs in secondary lymphoid organs where T cells encounter alloantigens presented by host DCs and differentiate to effectors. Antigen presentation at these sites occurs principally via transfer of intact, donor MHC-peptide complexes from graft cells to host DCs (cross-dressing) or by uptake and processing of donor antigens into allopeptides bound to self-MHC molecules (indirect presentation). The second step takes place in the graft, where effector T cells reengage with host DCs before causing rejection. How host DCs present alloantigens to T cells in the graft is not known. Using mouse islet and kidney transplantation models, imaging cytometry, and 2-photon intravital microscopy, we demonstrate extensive cross-dressing of intragraft host DCs with donor MHC-peptide complexes that occurred early after transplantation, whereas host DCs presenting donor antigen via the indirect pathway were rare. Cross-dressed DCs stably engaged TCR-transgenic effector CD8+ T cells that recognized donor antigen and were sufficient for sustaining acute rejection. In the chronic kidney rejection model, cross-dressing declined over time but was still conspicuous 8 weeks after transplantation. We conclude that cross-dressing of host DCs with donor MHC molecules is a major antigen presentation pathway driving effector T cell responses within allografts.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Rejeição de Enxerto/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Transplante de Rim , Ativação Linfocitária , Aloenxertos , Animais , Linfócitos T CD8-Positivos/patologia , Células Dendríticas/patologia , Rejeição de Enxerto/patologia , Camundongos , Camundongos Knockout , Imunologia de Transplantes
8.
Am J Health Behav ; 43(6): 1148-1161, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31662173

RESUMO

Objective: The aim of this study was to identify lifestyle profiles of young adult males and females based on their alcohol, diet, and exercise behaviors and then link these profiles with health. Method: We used the nationally representative 2017 Behavioral Risk Factor Surveillance System (BRFSS; N = 17,286; 47% female; Mage = 23.22; SD = 3.16; 65% white) to examine profiles of alcohol use, daily fruit and vegetable intake, fried potato intake, and exercise per week using latent profile analysis. Participants also reported the days their general, physical, and mental health were poor and BMI. Results: Five distinct profiles for both males and females were identified: Healthy Eaters/Exercisers, Moderates, Unhealthy Eaters, Medium Drinkers, and Heavy Drinkers. Heavy Drinkers and Unhealthy Eaters reported the most days of poor mental and physical health. Conclusions: Heavy drinkers and unhealthy eaters had the highest number of days of poor health, which also places them at risk for a host of health adversities throughout adulthood. Examining motivations behind young adults' patterns of consumption and activity is an important future direction to identify mechanisms for healthy lifestyle promotion during the transition to adulthood.


Assuntos
Comportamentos Relacionados com a Saúde , Estilo de Vida , Adolescente , Adulto , Sistema de Vigilância de Fator de Risco Comportamental , Exercício Físico , Feminino , Humanos , Masculino , Estados Unidos , Adulto Jovem
9.
J Acad Nutr Diet ; 119(11): 1875-1881, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31302035

RESUMO

BACKGROUND: Few studies use longitudinal designs to assess patterns of body mass index (BMI) change from adolescence to adulthood or incorporate severe obesity as a unique subgroup. OBJECTIVE: To examine patterns of BMI trajectories from adolescence to adulthood and identify demographic characteristics associated with each BMI trajectory pattern. DESIGN: Height, weight, and demographic characteristics were drawn from Waves I to V of the nationally representative school-based sample of the National Longitudinal Study of Adolescent to Adult Health (Add Health) conducted from 1994 to 2018 (data collection is ongoing). PARTICIPANTS/SETTING: Participants included 3,315 (55.5% female) subjects responding to in-home interviews across all five Waves of Add Health. MAIN OUTCOME MEASURES: BMI at each wave modeled over time. STATISTICAL ANALYSES: Latent class growth modeling and logistic regression analysis using population sample weights. RESULTS: Five classes of weight patterns best fit the sample. Twenty-nine percent of the sample had an always healthy BMI (class 1) and 34.9% changed from healthy weight to overweight (class 2). Moving from healthy weight to obese comprised 21.8% of the sample (class 3). BMI patterns increasing from overweight to obese (class 4) and from obese to severely obese (class 5) comprised 7.6% and 7.1% of the sample, respectively. Weight change was similar for males and females with some racial or ethnic minority participants more likely to be severely obese in adulthood. CONCLUSIONS: Results emphasize the importance of tracking weight longitudinally and point to a nationally representative trend of increasing BMI during the transition to adulthood. There was no substantive decreasing trend identified in the sample. Findings highlight the need for effective early and ongoing intervention and prevention strategies and can aid in identification of vulnerable youth who are at the highest risk for moving to problematic weight categories.


Assuntos
Índice de Massa Corporal , Peso Corporal , Análise de Classes Latentes , Adolescente , Adulto , Estatura , Etnicidade , Feminino , Nível de Saúde , Humanos , Estudos Longitudinais , Masculino , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Fatores de Risco , Adulto Jovem
10.
J Bacteriol ; 201(19)2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31331977

RESUMO

Bacteria that have the capacity to fill the same niche will compete with one another for the space and resources available within an ecosystem. Such competition is heightened among different strains of the same bacterial species. Nevertheless, different strains often inhabit the same host. The molecular mechanisms that impact competition between different strains within the same host are poorly understood. To address this knowledge gap, the type VI secretion system (T6SS), which is a mechanism for bacteria to kill neighboring cells, was examined in the marine bacterium Vibrio fischeri Different strains of V. fischeri naturally colonize the light organ of the bobtail squid Euprymna scolopes The genome of FQ-A001, a T6SS-positive strain, features two hcp genes that are predicted to encode identical subunits of the T6SS. Coincubation assays showed that either hcp gene is sufficient for FQ-A001 to kill another strain via the T6SS in vitro Additionally, induction of hcp expression is sufficient to induce killing activity in an FQ-A001 mutant lacking both hcp genes. Squid colonization assays involving inocula of FQ-A001-derived strains mixed with ES114 revealed that both hcp genes must be deleted for FQ-A001 and ES114 to occupy the same space within the light organ. These experimental results provide insight into the genetic factors necessary for the T6SS of V. fischeri to function in vivo, thereby increasing understanding of the molecular mechanisms that impact strain diversity within a host.IMPORTANCE Different bacterial strains compete to occupy the same niche. The outcome of such competition can be affected by the type VI secretion system (T6SS), an intercellular killing mechanism of bacteria. Here an animal-bacterial symbiosis is used as a platform for study of the genetic factors that promote the T6SS-mediated killing of one strain by another. Identification of the molecular determinants of T6SS function in vivo contributes to the understanding of how different strains interact within a host.


Assuntos
Aliivibrio fischeri/fisiologia , Decapodiformes/microbiologia , Sistemas de Secreção Tipo VI/genética , Aliivibrio fischeri/metabolismo , Animais , Especificidade de Hospedeiro , Família Multigênica , Fenótipo , Simbiose , Sistemas de Secreção Tipo VI/metabolismo
11.
Sci Immunol ; 2(12)2017 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-28783664

RESUMO

Mice devoid of T, B, and natural killer (NK) cells distinguish between self and allogeneic nonself despite the absence of an adaptive immune system. When challenged with an allograft, they mount an innate response characterized by accumulation of mature, monocyte-derived dendritic cells (DCs) that produce interleukin-12 and present antigen to T cells. However, the molecular mechanisms by which the innate immune system detects allogeneic nonself to generate these DCs are not known. To address this question, we studied the innate response of Rag2-/- γc-/- mice, which lack T, B, and NK cells, to grafts from allogeneic donors. By positional cloning, we identified that donor polymorphism in the gene encoding signal regulatory protein α (SIRPα) is a key modulator of the recipient's innate allorecognition response. Donors that differed from the recipient in one or both Sirpa alleles elicited an innate alloresponse. The response was mediated by binding of donor SIRPα to recipient CD47 and was modulated by the strength of the SIRPα-CD47 interaction. Therefore, sensing SIRPα polymorphism by CD47 provides a molecular mechanism by which the innate immune system distinguishes between self and allogeneic nonself independently of T, B, and NK cells.

12.
Kidney Int ; 90(4): 818-27, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27528552

RESUMO

Bony fish are among the first vertebrates to possess an innate and adaptive immune system. In these species, the kidney has a dual function: filtering solutes similar to mammals and acting as a lymphoid organ responsible for hematopoiesis and antigen processing. Recent studies have shown that the mammalian kidney has an extensive network of mononuclear phagocytes, whose function is not fully understood. Here, we employed two-photon intravital microscopy of fluorescent reporter mice to demonstrate that renal dendritic cells encase the microvasculature in the cortex, extend dendrites into the peritubular capillaries, and sample the blood for antigen. We utilized a mouse model of systemic bacterial infection as well as immune complexes to demonstrate antigen uptake by renal dendritic cells. As a consequence, renal dendritic cells mediated T-cell migration into the kidney in an antigen-dependent manner in the setting of bacterial infection. Thus, renal dendritic cells may be uniquely positioned to play an important role not only in surveillance of systemic infection but also in local infection and autoimmunity.


Assuntos
Autoimunidade , Infecções Bacterianas/imunologia , Movimento Celular/imunologia , Células Dendríticas/imunologia , Rim/imunologia , Linfócitos T/fisiologia , Animais , Apresentação de Antígeno/imunologia , Complexo Antígeno-Anticorpo , Células Dendríticas/ultraestrutura , Microscopia Intravital , Rim/irrigação sanguínea , Rim/citologia , Rim/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência por Excitação Multifotônica , Modelos Animais
13.
Nat Commun ; 7: 12623, 2016 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-27554168

RESUMO

Successful engraftment of organ transplants has traditionally relied on preventing the activation of recipient (host) T cells. Once T-cell activation has occurred, however, stalling the rejection process becomes increasingly difficult, leading to graft failure. Here we demonstrate that graft-infiltrating, recipient (host) dendritic cells (DCs) play a key role in driving the rejection of transplanted organs by activated (effector) T cells. We show that donor DCs that accompany heart or kidney grafts are rapidly replaced by recipient DCs. The DCs originate from non-classical monocytes and form stable, cognate interactions with effector T cells in the graft. Eliminating recipient DCs reduces the proliferation and survival of graft-infiltrating T cells and abrogates ongoing rejection or rejection mediated by transferred effector T cells. Therefore, host DCs that infiltrate transplanted organs sustain the alloimmune response after T-cell activation has already occurred. Targeting these cells provides a means for preventing or treating rejection.


Assuntos
Células Dendríticas/imunologia , Rejeição de Enxerto/imunologia , Linfócitos T/imunologia , Animais , Transplante de Coração , Transplante de Rim , Ativação Linfocitária , Camundongos , Transplantes
14.
J Immunol ; 197(4): 1471-6, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27357151

RESUMO

Pancreatic islet transplantation is a promising therapy for diabetes, but acute rejection of the islets by host effector T cells has hindered clinical application. In this study, we addressed the mechanisms of CD8(+) effector T cell migration to islet grafts because interrupting this step is key to preventing rejection. We found that effector T cell migration to revascularized islet transplants in mice is dependent on non-self Ag recognition rather than signaling via Gαi-coupled chemokine receptors. Presentation of non-self Ag by donor cells was necessary for migration, whereas Ag presentation by recipient cells was dispensable. We also observed that deficiency of SKAP1, an immune cell adaptor downstream of the TCR and important for integrin activation, prolongs allograft survival but does not reduce effector T cell migration to the graft. Therefore, effector T cell migration to transplanted islets is Ag driven, not chemokine driven, but SKAP1 does not play a critical role in this process.


Assuntos
Apresentação de Antígeno/imunologia , Linfócitos T CD8-Positivos/imunologia , Quimiotaxia de Leucócito/imunologia , Rejeição de Enxerto/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Animais , Ilhotas Pancreáticas/imunologia , Camundongos , Modelos Animais
15.
Sex Health ; 11(6): 561-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25435193

RESUMO

UNLABELLED: Background Women's risk for sexually transmitted diseases (STDs) were examined in terms of adolescent and young adult weight status, self-esteem trajectories and weight contentment using two waves of a nationally representative dataset. METHODS: Using Waves 1 and 3 of the National Longitudinal Study of Adolescent Health, body mass index (BMI), self-esteem and weight contentment were examined during adolescence and young adulthood to assess the likelihood of STDs among 4000 young adult single women. RESULTS: Change in BMI, specifically weight loss between adolescence and young adulthood, significantly increased women's risk for STDs. Continuously low self-esteem during adolescence and young adulthood significantly increased women's risk for STDs. When women's contentment with their weight decreased from adolescence to young adulthood, women's risk for STDs was greater. Regardless of other variables, Black women were more likely to have an STD. CONCLUSIONS: RESULTS suggest that women's self-perception is important in reducing sexual risk; specifically, patterns of self-esteem, BMI and weight contentment across developmental periods should be a critical focus of research and practice related to adolescent and young adult sexual health. There are many known benefits to fostering self-esteem during adolescence and findings from this study add STD prevention among young women to this list. RESULTS emphasise the needed prevention during adolescence to address self-perspective and self-esteem for the long-term sexual well-being of young women.

16.
J Clin Invest ; 124(8): 3579-89, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24983319

RESUMO

Maturation of T cell-activating APCs directly links innate and adaptive immunity and is typically triggered by microbial infection. Transplantation of allografts, which are sterile, generates strong T cell responses; however, it is unclear how grafts induce APC maturation in the absence of microbial-derived signals. A widely accepted hypothesis is that dying cells in the graft release "danger" molecules that induce APC maturation and initiate the adaptive alloimmune response. Here, we demonstrated that danger signals associated with dying cells are not sufficient to initiate alloimmunity, but that recognition of allogeneic non-self by the innate immune system is required. In WT as well as in T cell-, B cell-, and innate lymphoid cell-deficient mice, allogeneic grafts elicited persistent differentiation of monocytes into mature DCs that expressed IL-12 and stimulated T cell proliferation and IFN-γ production. In contrast, syngeneic grafts in the same mice elicited transient and less pronounced differentiation of monocytes into DCs, which neither expressed IL-12 nor stimulated IFN-γ production. In a model in which T cell recognition is restricted to a single foreign antigen on the graft, rejection occurred only if the allogeneic non-self signal was also sensed by the host's innate immune system. These findings underscore the importance of innate recognition of allogeneic non-self by monocytes in initiating graft rejection.


Assuntos
Rejeição de Enxerto/etiologia , Monócitos/imunologia , Imunidade Adaptativa , Aloenxertos , Animais , Linfócitos B/imunologia , Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Células Dendríticas/imunologia , Feminino , Rejeição de Enxerto/imunologia , Transplante de Coração , Imunidade Inata , Isoantígenos , Isoenxertos , Transplante de Rim , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos Transgênicos , Fator 88 de Diferenciação Mieloide/deficiência , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Transdução de Sinais/imunologia , Linfócitos T/imunologia , Fatores de Tempo
17.
J Youth Adolesc ; 43(9): 1563-75, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24907892

RESUMO

Family stress models illustrate how communities affect youth outcomes through effects on parents and studies consistently show the enduring effects of early community context. The present study takes a different approach identifying human agency during adolescence as a potentially significant promotive factor mediating the relationship between community, parenting, and mental health. While agency is an important part of resilience, its longitudinal effects are unknown, particularly based on gender and race/ethnicity. The purpose of this research was to model the long-term effects of community structural adversity and social resources as predictors of adolescent depressive symptom trajectories via indirect effects of parental happiness, parent-child relationships, and human agency. Latent growth analyses were conducted with 1,796 participants (53% female; 56% White) across four waves of the National Longitudinal Study of Adolescent Health spanning adolescence (Wave 1) through adulthood (Wave 4). The results identified agency as an important promotive factor during adolescence with long-term mental health benefits, but only for White and male participants. For these individuals, community social resources and the quality of the parent-child relationship were related to higher levels of agency and more positive mental health trajectories. Although community social resources similarly benefitted parenting and agency among females and non-White participants, there were no significant links between agency and depressive symptoms for these youth. The results suggest that agency remains an important, but poorly understood concept and additional work is necessary to continue unpacking its meaning for diverse groups of youth.


Assuntos
Depressão/psicologia , Etnicidade/psicologia , Relações Pais-Filho , Poder Familiar/psicologia , Resiliência Psicológica , Autoeficácia , Meio Social , Adolescente , Criança , Depressão/etnologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Modelos Psicológicos , Modelos Estatísticos , National Longitudinal Study of Adolescent Health , Relações Pais-Filho/etnologia , Poder Familiar/etnologia , Psicologia do Adolescente , Fatores Sexuais , Apoio Social , Estresse Psicológico , Estados Unidos
18.
J Clin Invest ; 123(6): 2663-71, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23676459

RESUMO

The migration of effector or memory T cells to the graft is a critical event in the rejection of transplanted organs. The prevailing view is that the key steps involved in T cell migration - integrin-mediated firm adhesion followed by transendothelial migration - are dependent on the activation of Gαi-coupled chemokine receptors on T cells. In contrast to this view, we demonstrated in vivo that cognate antigen was necessary for the firm adhesion and transendothelial migration of CD8+ effector T cells specific to graft antigens and that both steps occurred independent of Gαi signaling. Presentation of cognate antigen by either graft endothelial cells or bone marrow-derived APCs that extend into the capillary lumen was sufficient for T cell migration. The adhesion and transmigration of antigen-nonspecific (bystander) effector T cells, on the other hand, remained dependent on Gαi, but required the presence of antigen-specific effector T cells. These findings underscore the primary role of cognate antigen presented by either endothelial cells or bone marrow-derived APCs in the migration of T cells across endothelial barriers and have important implications for the prevention and treatment of graft rejection.


Assuntos
Apresentação de Antígeno , Linfócitos T CD8-Positivos/fisiologia , Transplante de Coração/imunologia , Transplante de Rim/imunologia , Migração Transendotelial e Transepitelial/imunologia , Transferência Adotiva , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/transplante , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/transplante , Adesão Celular , Vasos Coronários/imunologia , Vasos Coronários/patologia , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/fisiologia , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Imunoterapia Adotiva , Rim/irrigação sanguínea , Rim/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Miocárdio/imunologia , Receptores de Quimiocinas/fisiologia , Transdução de Sinais , Imagem com Lapso de Tempo
19.
Am J Health Behav ; 36(2): 275-88, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22370264

RESUMO

OBJECTIVE: To examine valuation of life, loneliness, and depressed mood as mediating the association between age and race/ethnicity and health outcomes among older adult male prisoners. METHODS: Survey of 261 male prisoners ages 45-80 from 8 Oklahoma correctional facilities. RESULTS: African American prisoners report fewer health conditions than White prisoners - a finding mediated by significantly greater valuation of life, less loneliness, and lower depressed mood among African American prisoners. Older prisoners reported more health conditions than younger prisoners independent of other study variables. CONCLUSION: Results suggest improving inmates' internal states will reduce incidence of illness and disease among older male offenders and associated healthcare costs.


Assuntos
Depressão/psicologia , Solidão/psicologia , Prisioneiros/psicologia , Valor da Vida , Afeto , Idoso , Idoso de 80 Anos ou mais , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Oklahoma , Prisões
20.
Transpl Immunol ; 26(2-3): 113-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22226941

RESUMO

BACKGROUND: Acute allograft rejection is dependent on adaptive immunity, but it is unclear whether the same is true for chronic rejection. Here we asked whether innate immunity alone is sufficient for causing chronic rejection of mouse cardiac allografts. METHODS: We transplanted primarily vascularized cardiac grafts to recombinase activating gene-knockout (RAG(-/-)) mice that lack T and B cells but have an intact innate immune system. Recipients were left unmanipulated, received adjuvants that stimulate innate immunity, or were reconstituted with B-1 lymphocytes to generate natural IgM antibodies. In a second model, we transplanted cardiac allografts to mice that lack secondary lymphoid tissues (splenectomized aly/aly recipients) and studied the effect of NK cell inactivation on T cell-mediated chronic rejection. RESULTS: Acute cardiac allograft rejection was not observed in any of the recipients. Histological analysis of allografts harvested 50 to 90 days after transplantation to RAG(-/-) mice failed to identify chronic vascular or parenchymal changes beyond those observed in control syngeneic grafts. Chronic rejection of cardiac allografts parked in splenectomized aly/aly mice was observed only after the transfer of exogenously activated T cells. NK inactivation throughout the experiment, or during the parking period alone, reduced the severity of T cell-dependent chronic rejection. CONCLUSIONS: The innate immune system alone is not sufficient for causing chronic rejection. NK cells predispose healed allografts to T cell-dependent chronic rejection and may contribute to chronic allograft pathology.


Assuntos
Rejeição de Enxerto/imunologia , Transplante de Coração/imunologia , Imunidade Inata , Ativação Linfocitária , Linfócitos T/imunologia , Animais , Subpopulações de Linfócitos B/imunologia , Células Matadoras Naturais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Transplante Homólogo
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