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1.
Mucosal Immunol ; 16(2): 167-179, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36623588

RESUMO

Psoriasis is a common chronic inflammatory skin disease with no cure. It is driven by the interleukin (IL)-23/IL-17A axis and type 17 T helper cells; however, recently, group 3 innate lymphoid cells (ILC3s) have also been implicated. Despite being the focus of much research, factors regulating the activity of ILC3s remain incompletely understood. Immune regulatory pathways are particularly important at barrier sites, such as the skin, gut, and lungs, which are exposed to environmental substances and microbes. CD200R1 is an immune regulatory cell surface receptor that inhibits proinflammatory cytokine production in myeloid cells. CD200R1 is also highly expressed on ILCs, where its function remains largely unexplored. We previously observed reduced CD200R1 signaling in psoriasis-affected skin, suggesting that dysregulation may promote disease. Here, we show that contrary to this, psoriasis models are less severe in CD200R1-deficient mice due to reduced IL-17 production. Here, we uncover a key cell-intrinsic role for CD200R1 in promoting IL-23-driven IL-17A production by ILC3s by promoting signal transducer and activator of transcription 3 activation. Therefore, contrary to its inhibitory role in myeloid cells, CD200R1 is required on ILC3 to promote IL-23-stimulated signal transducer and activator of transcription 3 activation, triggering optimal IL-17 production.


Assuntos
Interleucina-17 , Receptores de Orexina , Psoríase , Fator de Transcrição STAT3 , Animais , Camundongos , Imunidade Inata , Interleucina-17/metabolismo , Interleucina-23/metabolismo , Linfócitos , Receptores de Orexina/metabolismo , Psoríase/metabolismo , Fator de Transcrição STAT3/metabolismo
2.
Clin Diabetes ; 40(4): 434-441, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36385976

RESUMO

The purpose of this secondary qualitative data analysis was to assess the frequency and context of stigmatizing language used by health care providers (HCPs). The authors conducted content and thematic analysis of in-depth face-to-face and telephone interviews with HCPs in southeastern Ohio. Participants frequently used labeling language, such as "diabetic" and "noncompliant," as well as language with negative connotations, such as "control," "testing," and "regimen." These findings offer a real-world glimpse of how HCPs communicate about people with diabetes in this region of the country.

3.
Immun Inflamm Dis ; 10(7): e648, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35759230

RESUMO

INTRODUCTION: The skin immune system is tightly regulated to prevent inappropriate inflammation in response to harmless environmental substances. This regulation is actively maintained by mechanisms including cytokines and cell surface receptors and its loss results in inflammatory disease. In the case of psoriasis, inappropriate immune activation leads to IL-17-driven chronic inflammation, but molecular mechanisms underlying this loss of regulation are not well understood. Immunoglobulin family member CD200 and its receptor, CD200R1, are important regulators of inflammation. Therefore, we determined if this pathway is dysregulated in psoriasis, and how this affects immune cell activity. METHODS: Human skin biopsies were examined by quantitative polymerase chain reaction, flow cytometry, and immunohistochemistry. The role of CD200R1 in regulating psoriasis-like skin inflammation was examined using CD200R1 blocking antibodies in mouse psoriasis models. CD200R1 blocking antibodies were also used in an in vivo neutrophil recruitment assay and in vitro assays to examine macrophage, innate lymphoid cell, γδ T cell, and neutrophil activity. RESULTS: We reveal that CD200 and signaling via CD200R1 are reduced in non-lesional psoriasis skin. In mouse models of psoriasis CD200R1 was shown to limit psoriasis-like inflammation by enhancing acanthosis, CCL20 production and neutrophil recruitment, but surprisingly, macrophage function and IL-17 production were not affected, and neutrophil reactive oxygen species production was reduced. CONCLUSION: Collectively, these data show that CD200R1 affects neutrophil function and limits inflammatory responses in healthy skin by restricting neutrophil recruitment. However, the CD200 pathway is reduced in psoriasis, resulting in a loss of immune control, and increased neutrophil recruitment in mouse models. In conclusion, we highlight CD200R1:CD200 as a pathway that might be targeted to dampen inflammation in patients with psoriasis.


Assuntos
Interleucina-17 , Psoríase , Animais , Anticorpos Bloqueadores , Antígenos CD/metabolismo , Humanos , Imunidade Inata , Inflamação/metabolismo , Linfócitos/metabolismo , Camundongos , Infiltração de Neutrófilos , Receptores de Orexina/genética , Receptores de Orexina/metabolismo
4.
Cell Death Discov ; 7(1): 383, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34893585

RESUMO

The ability of SARS-CoV to infect different species, including humans, dogs, cats, minks, ferrets, hamsters, tigers, and deer, pose a continuous threat to human and animal health. Pigs, though closely related to humans, seem to be less susceptible to SARS-CoV-2. Former in vivo studies failed to demonstrate clinical signs and transmission between pigs, while later attempts using a higher infectious dose reported viral shedding and seroconversion. This study investigated species-specific cell susceptibility, virus dose-dependent infectivity, and infection kinetics, using primary human (HRECs) and porcine (PRECs) respiratory epithelial cells. Despite higher ACE2 expression in HRECs compared to PRECs, SARS-CoV-2 infected, and replicated in both PRECs and HRECs in a dose-dependent manner. Cytopathic effect was particularly more evident in PRECs than HRECs, showing the hallmark morphological signs of apoptosis. Further analysis confirmed an early and enhanced apoptotic mechanism driven through caspase 3/7 activation, limiting SARS-CoV-2 propagation in PRECs compared to HRECs. Our findings shed light on a possible mechanism of resistance of pigs to SARS-CoV-2 infection, and it may hold therapeutic value for the treatment of COVID-19.

5.
Arch Virol ; 166(9): 2551-2561, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34259914

RESUMO

The aim of this study was to identify and validate a sensitive, high-throughput, and cost-effective SARS-CoV-2 real-time RT-PCR assay to be used as a surveillance and diagnostic tool for SARS-CoV-2 in a university surveillance program. We conducted a side-by-side clinical evaluation of a newly developed SARS-CoV-2 multiplex assay (EZ-SARS-CoV-2 Real-Time RT-PCR) with the commercial TaqPath COVID-19 Combo Kit, which has an Emergency Use Authorization from the FDA. The EZ-SARS-CoV-2 RT-PCR incorporates two assays targeting the SARS-CoV-2 N gene, an internal control targeting the human RNase P gene, and a PCR inhibition control in a single reaction. Nasopharyngeal (NP) and anterior nares (AN) swabs were tested as individuals and pools with both assays and in the ABI 7500 Fast and the QuantStudio 5 detection platforms. The analytical sensitivity of the EZ-SARS-CoV-2 RT-PCR assay was 250 copies/ml or approximately 1.75 genome copy equivalents per reaction. The clinical performance of the EZ-SARS-CoV-2 assay was evaluated using NP and AN samples tested in other laboratories. The diagnostic sensitivity of the assay ranged between 94 and 96% across the detection platforms, and the diagnostic specificity was 94.06%. The positive predictive value was 94%, and the negative predictive value ranged from 94 to 96%. Pooling five NP or AN specimens yielded 93% diagnostic sensitivity. The overall agreement between these SARS-CoV-2 RT-PCR assays was high, supported by a Cohen's kappa value of 0.93. The EZ-SARS-CoV-2 RT-PCR assay performance attributes of high sensitivity and specificity with AN sample matrix and pooled upper respiratory samples support its use in a high-throughput surveillance testing program.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Proteínas do Nucleocapsídeo de Coronavírus/genética , Reação em Cadeia da Polimerase Multiplex/métodos , RNA Viral/genética , SARS-CoV-2/genética , COVID-19/epidemiologia , COVID-19/virologia , Teste de Ácido Nucleico para COVID-19/economia , Teste de Ácido Nucleico para COVID-19/instrumentação , Monitoramento Epidemiológico , Expressão Gênica , Humanos , Reação em Cadeia da Polimerase Multiplex/economia , Reação em Cadeia da Polimerase Multiplex/instrumentação , Cavidade Nasal/virologia , Nasofaringe/virologia , Fosfoproteínas/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Manejo de Espécimes/métodos , Carga Viral
6.
Front Immunol ; 12: 670471, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33936115

RESUMO

Mucosal surfaces, as a first barrier with the environment are especially susceptible to damage from both pathogens and physical trauma. Thus, these sites require tightly regulated repair programs to maintain barrier function in the face of such insults. Barrier sites are also enriched for unconventional lymphocytes, which lack rearranged antigen receptors or express only a limited range of such receptors, such as ILCs (Innate Lymphoid Cells), γδ T Cells and MAIT (Mucosal-Associated Invariant T Cells). Recent studies have uncovered critical roles for unconventional lymphocytes in regulating mucosal barrier function, and, in particular, have highlighted their important involvement in barrier repair. The production of growth factors such as amphiregulin by ILC2, and fibroblast growth factors by γδ T cells have been shown to promote tissue repair at multiple barrier sites. Additionally, MAIT cells have been shown to exhibit pro-repair phenotypes and demonstrate microbiota-dependent promotion of murine skin healing. In this review we will discuss how immune responses at mucosal sites are controlled by unconventional lymphocytes and the ways in which these cells promote tissue repair to maintain barrier integrity in the skin, gut and lungs.


Assuntos
Imunidade nas Mucosas/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Humanos , Células T Invariantes Associadas à Mucosa/imunologia
7.
Front Immunol ; 11: 598636, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33250899

RESUMO

Breathing allows a multitude of airborne microbes and microbial compounds to access the lung. Constant exposure of the pulmonary microenvironment to immunogenic particles illustrates the need for proper control mechanisms ensuring the differentiation between threatening and harmless encounters. Discrimination between live and dead bacteria has been suggested to be such a mechanism. In this study, we performed infection studies of murine precision cut lung slices (PCLS) with live or heat-killed P. aeruginosa, in order to investigate the role of viability for induction of an innate immune response. We demonstrate that PCLS induce a robust transcriptomic rewiring upon infection with live but not heat-killed P. aeruginosa. Using mutants of the P. aeruginosa clinical isolate CHA, we show that the viability status of P. aeruginosa is assessed in PCLS by TLR5-independent sensing of flagellin and recognition of the type three secretion system. We further demonstrate that enhanced cytokine expression towards live P. aeruginosa is mediated by uptake of viable but not heat-killed bacteria. Finally, by using a combined approach of receptor blockage and genetically modified PCLS we report a redundant involvement of MARCO and CD200R1 in the uptake of live P. aeruginosa in PCLS. Altogether, our results show that PCLS adapt the extent of cytokine expression to the viability status of P. aeruginosa by specifically internalizing live bacteria.


Assuntos
Citocinas/metabolismo , Interações Hospedeiro-Patógeno , Pneumonia Bacteriana/metabolismo , Pneumonia Bacteriana/microbiologia , Infecções por Pseudomonas/metabolismo , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/fisiologia , Animais , Biópsia , Biologia Computacional/métodos , Modelos Animais de Doenças , Flagelina/metabolismo , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Viabilidade Microbiana , Pneumonia Bacteriana/genética , Pneumonia Bacteriana/imunologia , Infecções por Pseudomonas/genética , Infecções por Pseudomonas/imunologia , Transcriptoma , Sistemas de Secreção Tipo III/metabolismo
8.
J Pediatr ; 217: 196-198, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31668481

RESUMO

Neonatal withdrawal can be difficult to treat in infants with co-exposure to opiates and gabapentin. Because maternal self-report can underestimate exposures, we evaluated the effect of universal toxicology screening for gabapentin. Identification of co-exposure to opiates and gabapentin increased after implementation of toxicology screening, with implications for improved neonatal care.


Assuntos
Gabapentina/efeitos adversos , Síndrome de Abstinência Neonatal/prevenção & controle , Alcaloides Opiáceos/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Analgésicos Opioides/efeitos adversos , Antagonistas de Aminoácidos Excitatórios/efeitos adversos , Feminino , Seguimentos , Humanos , Incidência , Recém-Nascido , Síndrome de Abstinência Neonatal/diagnóstico , Síndrome de Abstinência Neonatal/epidemiologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/diagnóstico , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Estudos Retrospectivos , West Virginia/epidemiologia
9.
Dalton Trans ; 45(5): 2148-55, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26549252

RESUMO

The group 14 chloropropargyls R3EC ≡ CCH2Cl (R3E = (n)Bu3Sn, Ph3Sn, Me2PhSi, (i)Pr3Si, (n)Pr3Si, (n)Bu3Si), obtained by a modified literature procedure, react with LiPPh2 to afford the novel propargyl phosphanes Ph2PCH2C ≡ CER3 in high yield, as viscous oils; (Me3Si)2PCH2C ≡ CSiPhMe2 is similarly obtained from LiP(SiMe3)2. In contrast, the reaction of PhC[triple bond, length as m-dash]CCH2MgCl with ClP(NEt2)2 fails to produce a comparable propargyl phosphane, but generates preferentially (>70%) the novel phosphinoallene (Et2N)2PC(Ph) = C = CH2, which is characterised spectroscopically, and through its reaction with HCl. The coordination chemistry of representative phosphanes is explored with respect to platinum and palladium for the first time.

10.
Am J Pharm Educ ; 79(1): 09, 2015 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-25741025

RESUMO

OBJECTIVE: To determine the quality of sleep among pharmacy students in the didactic portion of the curriculum at one school of pharmacy. METHODS: The study consisted of an anonymous, voluntary survey that included the Pittsburgh Sleep Quality Index (PSQI), a self-rated instrument that measures sleep habits for a month. RESULTS: The survey was completed by 253 students. Students in the lower grade point average (GPA) category had higher scores on 2 of 7 components of the PSQI and on the global score. Poor sleep quality, indicated by a global PSQI score of greater than 5, was reported by 140 students. The rate of poor sleeping was higher among students in the lower GPA category. CONCLUSION: Poor sleep quality was pervasive among surveyed pharmacy students in the didactic portion of the pharmacy school curriculum, especially among those with lower GPAs.


Assuntos
Qualidade de Vida , Sono , Estudantes de Farmácia/estatística & dados numéricos , Currículo/estatística & dados numéricos , Coleta de Dados , Educação em Farmácia/estatística & dados numéricos , Feminino , Hábitos , Humanos , Masculino , Faculdades de Farmácia/estatística & dados numéricos
11.
J Immunol ; 193(6): 2831-42, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25114101

RESUMO

The leukocyte-specific tyrosine phosphatase, CD45, severely impacts T cell development and activation by modulating TCR signaling. CD45-deficient (CD45KO) mice have reduced peripheral T cell numbers where CD8 T cells are underrepresented. In this article, we show that CD45KO mice are unable to support efficient homeostatic proliferation, affecting CD8 T cells more than CD4 T cells. Using CD45-RAG1 double-deficient (45RAGKO) mice, we show that lymphopenia-induced proliferation (LIP) of CD45-sufficient T cells is defective in a host environment lacking CD45 on innate immune cells. We identify two deficiencies in the 45RAGKO mice that affect LIP. One involves CD11c(+) cells and the second the production of IL-7 by lymphoid stromal cells. CD45KO dendritic cells were not defective in foreign Ag-induced T cell proliferation, yet CD45KO CD11c(+) cells were unable to rescue the spontaneous LIP in the 45RAGKO mice. This was in contrast with the CD45-sufficient CD11c(+) cells that partially rescued this spontaneous proliferation and did so without affecting IL-7 levels. The absence of CD45 also led to reduced IL-7 production by lymphoid stromal cells, suggesting an indirect effect of CD45 on innate immune cells in influencing IL-7 production by lymphoid stromal cells. These findings demonstrate a novel role for CD45 on innate immune cells in promoting lymphopenia-induced T cell proliferation and suggest that innate immune cells may communicate with stromal cells to regulate IL-7 production.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Antígenos Comuns de Leucócito/imunologia , Ativação Linfocitária/imunologia , Linfopenia/imunologia , Animais , Antígeno CD11c/biossíntese , Relação CD4-CD8 , Diferenciação Celular/imunologia , Proliferação de Células , Células Dendríticas/imunologia , Imunidade Inata , Interleucina-7/biossíntese , Antígenos Comuns de Leucócito/biossíntese , Antígenos Comuns de Leucócito/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/imunologia , Células Estromais/imunologia
12.
Chem Commun (Camb) ; 48(46): 5766-8, 2012 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-22552266

RESUMO

The reaction of isophthaloyl chloride and methyl-bis(trimethylsilyl)phosphane under mild conditions affords high yields of m-{-C(O)-C(6)H(4)(C(O)PMe)}(2) (1,10-dimethyl-1,10-diphospha-[3.3]-metacyclophane-2,9,11,18-tetraone): the first example of a diphosphametacyclophane.


Assuntos
Compostos Organofosforados/química , Piperidinas/química , Cristalografia por Raios X , Conformação Molecular , Compostos Organofosforados/síntese química , Piperidinas/síntese química , Teoria Quântica
13.
FEBS Lett ; 585(22): 3549-54, 2011 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-22020221

RESUMO

Latent HIV-1 (human immunodeficiency virus-1) provirus is unaffected by current AIDS (acquired immunodeficiency syndrome) therapies. We show here that chaetocin, an SUV39H1 histone methyltransferase inhibitor, causes 25-fold induction of latent HIV-1 expression, while producing minimal toxicity and without causing T cell activation. Induction is associated with loss of histone H3 lysine 9 (H3K9) trimethylation at the long terminal repeat (LTR) promoter, and a corresponding increase in H3K9 acetylation. The effect of chaetocin is amplified synergistically in combination with histone deacetylase (HDAC) inhibitors. These results indicate that chaetocin may provide a therapy to purge cells of latent HIV-1, possibly in combination with other chromatin remodeling drugs.


Assuntos
HIV-1/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Metiltransferases/antagonistas & inibidores , Proteínas Repressoras/antagonistas & inibidores , Linfócitos T/imunologia , Acetilação , Montagem e Desmontagem da Cromatina , Sinergismo Farmacológico , Repetição Terminal Longa de HIV , HIV-1/genética , HIV-1/metabolismo , Histonas/metabolismo , Humanos , Células Jurkat , Metilação , Metiltransferases/metabolismo , Piperazinas/farmacologia , Proteínas Repressoras/metabolismo , Linfócitos T/metabolismo , Ativação Viral , Latência Viral/efeitos dos fármacos
14.
Blood ; 115(16): 3249-57, 2010 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-20194894

RESUMO

The guanosine triphosphatases (GTPases) of the immunity-associated protein (GIMAP) family of putative GTPases has been implicated in the regulation of T-lymphocyte development and survival. A mouse conditional knockout allele was generated for the immune GTPase gene GIMAP1. Homozygous loss of this allele under the influence of the lymphoid-expressed hCD2-iCre recombinase transgene led to severe (> 85%) deficiency of mature T lymphocytes and, unexpectedly, of mature B lymphocytes. By contrast there was little effect of GIMAP1 deletion on immature lymphocytes in either B or T lineages, although in vitro studies showed a shortening of the survival time of both immature and mature CD4(+) single-positive thymocytes. These findings show a vital requirement for GIMAP1 in mature lymphocyte development/survival and draw attention to the nonredundant roles of members of the GIMAP GTPase family in these processes.


Assuntos
Linfócitos B/citologia , Diferenciação Celular/imunologia , GTP Fosfo-Hidrolases/metabolismo , Linfócitos T/citologia , Animais , Western Blotting , Separação Celular , Sobrevivência Celular , Citometria de Fluxo , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase , Transdução de Sinais/imunologia
15.
J Immunol ; 184(7): 3743-54, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20190135

RESUMO

Homeostatic control of the immune system involves mechanisms that ensure the self-tolerance, survival and quiescence of hematopoietic-derived cells. In this study, we demonstrate that the GTPase of immunity associated protein (Gimap)5 regulates these processes in lymphocytes and hematopoietic progenitor cells. As a consequence of a recessive N-ethyl-N-nitrosourea-induced germline mutation in the P-loop of Gimap5, lymphopenia, hepatic extramedullary hematopoiesis, weight loss, and intestinal inflammation occur in homozygous mutant mice. Irradiated fetal liver chimeric mice reconstituted with Gimap5-deficient cells lose weight and become lymphopenic, demonstrating a hematopoietic cell-intrinsic function for Gimap5. Although Gimap5-deficient CD4(+) T cells and B cells appear to undergo normal development, they fail to proliferate upon Ag-receptor stimulation although NF-kappaB, MAP kinase and Akt activation occur normally. In addition, in Gimap5-deficient mice, CD4(+) T cells adopt a CD44(high)CD62L(low)CD69(low) phenotype and show reduced IL-7ralpha expression, and T-dependent and T-independent B cell responses are abrogated. Thus, Gimap5-deficiency affects a noncanonical signaling pathway required for Ag-receptor-induced proliferation and lymphocyte quiescence. Antibiotic-treatment or the adoptive transfer of Rag-sufficient splenocytes ameliorates intestinal inflammation and weight loss, suggesting that immune responses triggered by microbial flora causes the morbidity in Gimap5-deficient mice. These data establish Gimap5 as a key regulator of hematopoietic integrity and lymphocyte homeostasis.


Assuntos
Linfócitos B/imunologia , Colite/imunologia , GTP Fosfo-Hidrolases/imunologia , Linfócitos T/imunologia , Síndrome de Emaciação/imunologia , Animais , Subpopulações de Linfócitos B/imunologia , Colite/genética , Feminino , GTP Fosfo-Hidrolases/genética , Proteínas de Ligação ao GTP , Hematopoese/genética , Hematopoese/imunologia , Células-Tronco Hematopoéticas/imunologia , Homeostase/genética , Homeostase/imunologia , Immunoblotting , Inflamação/genética , Inflamação/imunologia , Intestinos/imunologia , Intestinos/microbiologia , Intestinos/patologia , Hepatopatias/genética , Hepatopatias/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Tolerância a Antígenos Próprios/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Subpopulações de Linfócitos T/imunologia , Síndrome de Emaciação/genética
16.
Self Nonself ; 1(3): 259-268, 2010 07.
Artigo em Inglês | MEDLINE | ID: mdl-21487483

RESUMO

A mutation in the rat GIMAP5 gene predisposes for autoimmunity, most famously in the BB rat model of autoimmune type 1 diabetes mellitus. This mutation is associated with severe peripheral T lymphopenia, as is mutation of the same gene in mice, but the mechanism by which GIMAP5 normally protects T cells from death is unknown. GIMAP5 is a putative small GTPase, a class of proteins which often fulfil their functions in the vicinity of cellular membranes. The objective of this study was to determine the normal intracellular location of GIMAP5 in lymphoid cells. Combining studies in rat, mouse and human systems, novel monoclonal antibodies (mAbs) were used to examine the localization of GIMAP5 and the closely-related protein, GIMAP1, in lymphoid cells by means of confocal microscopy and sub-cellular fractionation combined with immunoblotting. Additionally, human Jurkat T cells that inducibly express epitope-tagged GIMAP5 were established and used in electron microscopy (EM). Endogenous GIMAP5 was found to be located in a membraneous compartment/s which was also detected by established markers of lysosomes. GIMAP1, by contrast, was found to be located in the Golgi apparatus. EM studies of the inducible Jurkat T cells also found GIMAP5 in lysosomes and, in addition, in multivesicular bodies. This study establishes that the endogenous location of GIMAP5 is in lysosomes and related compartments and provides a clearer context for hypotheses about its mechanism of action.

17.
Malar J ; 8: 53, 2009 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-19338674

RESUMO

BACKGROUND: GIMAP (GTPase of the immunity-associated protein family) proteins are a family of putative GTPases believed to be regulators of cell death in lymphomyeloid cells. GIMAP1 was the first reported member of this gene family, identified as a gene up-regulated at the RNA level in the spleens of mice infected with the malarial parasite, Plasmodium chabaudi. METHODS: A monoclonal antibody against mouse GIMAP1 was developed and was used to analyse the expression of the endogenous protein in tissues of normal mice and in defined sub-populations of cells prepared from lymphoid tissues using flow cytometry. It was also used to assess the expression of GIMAP1 protein after infection and/or immunization of mice with P. chabaudi. Real-time PCR analysis was employed to measure the expression of GIMAP1 for comparison with the protein level analysis. RESULTS: GIMAP1 protein expression was detected in all lineages of lymphocytes (T, B, NK), in F4/80+ splenic macrophages and in some lymphoid cell lines. Additional evidence is presented suggesting that the strong expression by mature B cells of GIMAP1 and other GIMAP genes and proteins seen in mice may be a species-dependent characteristic. Unexpectedly, no increase was found in the expression of GIMAP1 in P. chabaudi infected mice at either the mRNA or protein level, and this remained so despite applying a number of variations to the protocol. CONCLUSION: The model of up-regulation of GIMAP1 in response to infection/immunization with P. chabaudi is not a robustly reproducible experimental system. The GIMAP1 protein is widely expressed in lymphoid cells, with an interesting increase in expression in the later stages of B cell development. Alternative approaches will be required to define the functional role of this GTPase in immune cells.


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Malária/metabolismo , Proteínas de Membrana/metabolismo , Plasmodium chabaudi/imunologia , Baço/metabolismo , Regulação para Cima , Animais , Anticorpos Monoclonais , Western Blotting , Linhagem Celular , Citometria de Fluxo , GTP Fosfo-Hidrolases/metabolismo , Linfócitos/metabolismo , Malária/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase , Baço/citologia
18.
NeuroRehabilitation ; 21(2): 97-105, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16917157

RESUMO

Traditional rehabilitation for hemiplegia is not necessarily based on a supported theoretical foundation and some evidence questiones the efficacy of current practice. The uncertainty relating to underlying theories is a serious issue, henceforth there has been a move to base treatment strategies on scientific foundations which incorporate knowledge of human learning mechanisms and accompanying neurobiological processes. In this paper we argue that constraint induced movement therapy is a potentially very effective intervention that benefits from a strong theoretical grounding. It is demonstrated that the treatment mechanisms are supported by established behavioural learning theory and evidence of brain plasticity. As empirical support for the therapy is gradually mounting, the integration into mainstream practice lends itself as a natural course. In this paper, a series of issues surrounding the distribution of CIT such as constraint use, dose response relationships and accessibility to a wider group of patients are discussed. Further research in these areas is considered important for CIT integration into mainstream practice.


Assuntos
Terapia Comportamental , Difusão de Inovações , Terapia por Exercício , Restrição Física , Encefalopatias/complicações , Hemiplegia/etiologia , Hemiplegia/psicologia , Hemiplegia/reabilitação , Humanos , Prática Psicológica
19.
J Environ Qual ; 31(4): 1115-23, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12175028

RESUMO

The adsorption of As(V) and As(III) on synthetic two-line ferrihydrite in the presence and absence of a peat humic acid (HAp), Suwannee River fulvic acid (FA), or citric acid (CA) was investigated. Previous work with goethite has demonstrated the ability of dissolved organic carbon (DOC) to decrease As(V) and As(III) adsorption. The results obtained demonstrate that As(V) adsorption on ferrihydrite was decreased only in the presence of CA. Arsenate decreased the adsorption of all organic acids except HAp. Both FA and CA reduced As(III) adsorption on ferrihydrite, while HAp had no effect. Fulvic and citric acid adsorption on ferrihydrite was decreased in the presence of As(III); however, FA and CA adsorption increased at lower pH, which was consistent with decreased As(III) adsorption. Peat humic acid did not decrease As(III) adsorption, and we believe that the adsorption process of HAp and As(III) and As(V) on ferrihydrite are independent of each other. Previously, we observed that As(V) adsorption on goethite decreased in the presence of HAp > FA > CA, while As(III) adsorption on goethite was decreased similarly to that on ferrihydrite in the presence of CA > FA approximately HAp, yet As(III) adsorption on ferrihydrite was greater than on goethite. The observed differences between this study and the earlier study on goethite are believed to be an intricate function of ferrihydrite's surface characteristics, which affect the mechanisms of adsorption and hence the affinity of organic acids such as HAp, FA, and CA for the ferrihydrite surface. As such, the adsorption of DOCs to ferrihydrite are assumed to be less favorable and to occur with a fewer number of ligands, resulting in lower surface coverage of weaker bond strength.


Assuntos
Arseniatos/química , Arsenitos/química , Carbono/química , Ferritinas/química , Teratogênicos/química , Adsorção , Benzopiranos/química , Disponibilidade Biológica , Ácido Cítrico/química , Compostos Férricos , Substâncias Húmicas/química , Solo , Poluentes do Solo/análise , Solubilidade
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