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1.
Ann Diagn Pathol ; 62: 152077, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36549077

RESUMO

T-prolymphocytic leukemia (T-PLL) is a rare, aggressive T-cell leukemia, and patients typically present with marked peripheral blood lymphocytosis. Approximately 15-20 % of patients may present with moderate and relative stable lymphocytosis and an indolent clinical course that can persist for a few years. However, eventually these patients go on to develop marked lymphocytosis and rapidly progressive disease. We report a 72-year-old man who presented with multicompartmental lymphadenopathy and a normal complete blood count. Excision of left and right cervical lymph nodes showed replacement of the lymph node architecture by a small T-cell neoplasm positive for CD3, CD4, CD5, CD7 and TCL-1, and negative for CD8, CD20, CD30 and ALK. Subsequent bone marrow evaluation showed minimal bone marrow involvement by a T-cell neoplasm associated with TCL1A rearrangement in 11 % of cells supporting the diagnosis of T-PLL. Despite treatment, he showed progressive lymphadenopathy while remarkably maintaining normal white blood cell counts until he eventually developed leukocytosis of 110.9 × 103/uL 26 months later. Review of the literature identified only a single abstract reporting a patient with a similar lymphoma-like presentation and normal white blood cell count; however, that case showed significant bone marrow involvement in stark contrast to the current case. In summary, we report a highly unusual case of T-PLL can initially presenting with an aleukemic or lymphoma-like clinical picture, which can make establishing the diagnosis challenging.


Assuntos
Leucemia Prolinfocítica de Células T , Leucemia Prolinfocítica , Linfadenopatia , Linfocitose , Masculino , Humanos , Idoso , Linfocitose/patologia , Leucemia Prolinfocítica/patologia , Leucemia Prolinfocítica de Células T/diagnóstico , Leucemia Prolinfocítica de Células T/patologia , Medula Óssea/patologia , Linfadenopatia/patologia
2.
J Clin Microbiol ; 60(12): e0135622, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36472424

RESUMO

Early-onset neonatal sepsis due to Streptococcus agalactiae (group B Streptococcus [GBS]) infection is one of the leading causes of newborn mortality and morbidity. The latest guidelines published in 2019 recommended universal screening of GBS colonization among all pregnant women and intrapartum antibiotic prophylaxis for positive GBS. The updated procedures allow rapid molecular-based GBS screening using nutrient broth-enriched rectovaginal samples. Commercially available molecular assays for GBS diagnosis target mainly the cfb gene, which encodes a hemolysin protein responsible for producing the Christie-Atkins-Munch-Petersen (CAMP) factor. cfb is considered a conserved gene in essentially all GBS isolates. However, false-negative GBS results on Cepheid Xpert GBS and GBS LB tests due to deletions in or near the region that encodes cfb were reported recently. Therefore, the new Xpert GBS LB XC test was developed. This study is a multicenter evaluation of the new test for GBS identification from nutrient broth-enriched rectal/vaginal samples from antepartum women. A total of 621 samples were prospectively enrolled. The samples were tested with the Xpert GBS LB XC test, the composite comparator method, which included the Hologic Panther Fusion GBS test combined with bacterial culture, followed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) identification, and bacterial culture alone, followed by MALDI-TOF MS identification. The respective sensitivity and specificity of the Xpert GBS LB XC test were 99.3% and 98.7% compared to the composite comparator method and 99.1% and 91.8% compared to bacterial culture alone with MALDI-TOF MS identification. Overall, the Xpert GBS LB XC test performed comparatively to the composite comparator method and is equivalent to traditional bacterial culture followed by MALDI-TOF MS.


Assuntos
Complicações Infecciosas na Gravidez , Infecções Estreptocócicas , Recém-Nascido , Gravidez , Feminino , Humanos , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/microbiologia , Vagina/microbiologia , Streptococcus agalactiae/genética , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia , Sensibilidade e Especificidade
5.
Blood ; 128(26): 3061-3072, 2016 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-27799162

RESUMO

Autosomal dominant hyper-IgE syndrome (AD-HIES) is caused by dominant-negative mutations in STAT3; however, the molecular basis for mutant STAT3 allele dysfunction is unclear and treatment remains supportive. We hypothesized that AD-HIES mutations decrease STAT3 protein stability and that mutant STAT3 activity can be improved by agents that increase chaperone protein activity. We used computer modeling to characterize the effect of STAT3 mutations on protein stability. We measured STAT3 protein half-life (t1/2) and determined levels of STAT3 phosphorylated on tyrosine (Y) 705 (pY-STAT3) and mRNA levels of STAT3 gene targets in Epstein-Barr virus-transformed B (EBV) cells, human peripheral blood mononuclear cells (PBMCs), and mouse splenocytes incubated without or with chaperone protein modulators-HSF1A, a small-molecule TRiC modulator, or geranylgeranylacetone (GGA), a drug that upregulates heat shock protein (HSP) 70 and HSP90. Computer modeling predicted that 81% of AD-HIES mutations are destabilizing. STAT3 protein t1/2 in EBV cells from AD-HIES patients with destabilizing STAT3 mutations was markedly reduced. Treatment of EBV cells containing destabilizing STAT3 mutations with either HSF1A or GGA normalized STAT3 t1/2, increased pY-STAT3 levels, and increased mRNA levels of STAT3 target genes up to 79% of control. In addition, treatment of human PBMCs or mouse splenocytes containing destabilizing STAT3 mutations with either HSF1A or GGA increased levels of cytokine-activated pY-STAT3 within human CD4+ and CD8+ T cells and numbers of IL-17-producing CD4+ mouse splenocytes, respectively. Thus, most AD-HIES STAT3 mutations are destabilizing; agents that modulate chaperone protein function improve STAT3 stability and activity in T cells and may provide a specific treatment.


Assuntos
Síndrome de Job/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Citocinas/farmacologia , Proteínas de Ligação a DNA/metabolismo , Diterpenos/farmacologia , Meia-Vida , Fatores de Transcrição de Choque Térmico , Herpesvirus Humano 4/fisiologia , Humanos , Interleucina-17/metabolismo , Síndrome de Job/patologia , Camundongos , Modelos Moleculares , Proteínas Mutantes/metabolismo , Mutação/genética , Fosfotirosina/metabolismo , Ligação Proteica/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Fator de Transcrição STAT3/química , Fator de Transcrição STAT3/genética , Baço/patologia , Fatores de Transcrição/metabolismo
6.
Blood ; 125(4): 591-9, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25359994

RESUMO

Germline loss-of-function mutations in the transcription factor signal transducer and activator of transcription 3 (STAT3) cause immunodeficiency, whereas somatic gain-of-function mutations in STAT3 are associated with large granular lymphocytic leukemic, myelodysplastic syndrome, and aplastic anemia. Recently, germline mutations in STAT3 have also been associated with autoimmune disease. Here, we report on 13 individuals from 10 families with lymphoproliferation and early-onset solid-organ autoimmunity associated with 9 different germline heterozygous mutations in STAT3. Patients exhibited a variety of clinical features, with most having lymphadenopathy, autoimmune cytopenias, multiorgan autoimmunity (lung, gastrointestinal, hepatic, and/or endocrine dysfunction), infections, and short stature. Functional analyses demonstrate that these mutations confer a gain-of-function in STAT3 leading to secondary defects in STAT5 and STAT1 phosphorylation and the regulatory T-cell compartment. Treatment targeting a cytokine pathway that signals through STAT3 led to clinical improvement in 1 patient, suggesting a potential therapeutic option for such patients. These results suggest that there is a broad range of autoimmunity caused by germline STAT3 gain-of-function mutations, and that hematologic autoimmunity is a major component of this newly described disorder. Some patients for this study were enrolled in a trial registered at www.clinicaltrials.gov as #NCT00001350.


Assuntos
Doenças Autoimunes/genética , Doenças Genéticas Inatas/genética , Transtornos Linfoproliferativos/genética , Fator de Transcrição STAT3/genética , Adolescente , Adulto , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Criança , Pré-Escolar , Feminino , Doenças Genéticas Inatas/imunologia , Doenças Genéticas Inatas/patologia , Humanos , Lactente , Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/patologia , Masculino , Mutação , Fosforilação/genética , Fosforilação/imunologia , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/imunologia , Fator de Transcrição STAT3/imunologia , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia
7.
Am J Surg Pathol ; 48(6): e43-e64, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38451836

RESUMO

Breast implant-associated anaplastic large cell lymphoma has been recognized as a distinct entity in the World Health Organization classification of hematolymphoid neoplasms. These neoplasms are causally related to textured implants that were used worldwide until recently. Consequently, there is an increased demand for processing periprosthetic capsules, adding new challenges for surgeons, clinicians, and pathologists. In the literature, the focus has been on breast implant-associated anaplastic large cell lymphoma; however, benign complications related to the placement of breast implants occur in up to 20% to 30% of patients. Imaging studies are helpful in assessing patients with breast implants for evidence of implant rupture, changes in tissues surrounding the implants, or regional lymphadenopathy related to breast implants, but pathologic examination is often required. In this review, we couple our experience with a review of the literature to describe a range of benign lesions associated with breast implants that can be associated with different clinical presentations or pathogenesis and that may require different diagnostic approaches. We illustrate the spectrum of the most common of these benign disorders, highlighting their clinical, imaging, gross, and microscopic features. Finally, we propose a systematic approach for the diagnosis and handling of breast implant specimens in general.


Assuntos
Implante Mamário , Implantes de Mama , Linfoma Anaplásico de Células Grandes , Humanos , Implantes de Mama/efeitos adversos , Feminino , Linfoma Anaplásico de Células Grandes/patologia , Linfoma Anaplásico de Células Grandes/etiologia , Implante Mamário/efeitos adversos , Implante Mamário/instrumentação , Valor Preditivo dos Testes , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Relevância Clínica
8.
FASEB J ; 26(5): 1982-94, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22286690

RESUMO

Angiotensin II (AngII), the main effector peptide of the renin-angiotensin system (RAS), participates in multiple biological processes, including cell growth, apoptosis, and tissue remodeling. Since AngII activates, in different cell types, signal transducing pathways that are critical for mammary gland postlactational regression, we investigated the role of the RAS during this process. We found that exogenous administration of AngII in mammary glands of lactating Balb/c mice induced epithelium apoptosis [2.9±0.5% (control) vs. 9.6±1.1% (AngII); P < 0.001] and activation of the proapoptotic factor STAT3, an effect inhibited by irbesartan, an AT(1) receptor blocker. Subsequently, we studied the expression kinetics of RAS components during involution. We found that angiotensin-converting enzyme (ACE) mRNA expression peaked 6 h after weaning (5.7-fold; P<0.01), while induction of angiotensinogen and AT(1) and AT(2) receptors expression was detected 96 h after weaning (6.2-, 10-, and 6.2-fold increase, respectively; P<0.01). To assess the role of endogenously generated AngII, mice were treated with losartan, an AT(1) receptor blocker, during mammary involution. Mammary glands from losartan-treated mice showed activation of the survival factors AKT and BCL-(XL), significantly lower LIF and TNF-α mRNA expression (P<0.05), reduced apoptosis [12.1±2.1% (control) vs. 4.8±0.7% (losartan); P<0.001] and shedding of epithelial cells, inhibition of MMP-9 activity in a dose-dependent manner (80%; P<0.05; with losartan IC(50) value of 6.9 mg/kg/d] and lower collagen deposition and adipocyte invasion causing a delayed involution compared to vehicle-treated mice. Furthermore, mammary glands of forced weaned AT(1A)- and/or AT(1B)-deficient mice exhibited retarded apoptosis of epithelial cells [6.3±0.95% (WT) vs. 3.3±0.56% (AT(1A)/AT(1B) DKO); P<0.05] with remarkable delayed postlactational regression compared to wild-type animals. Taken together, these results strongly suggest that AngII, via the AT(1) receptor, plays a major role in mouse mammary gland involution identifying a novel role for the RAS. angiotensin system.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Glândulas Mamárias Animais/efeitos dos fármacos , Receptor Tipo 1 de Angiotensina/efeitos dos fármacos , Sistema Renina-Angiotensina , Angiotensina II/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Relação Dose-Resposta a Droga , Feminino , Marcação In Situ das Extremidades Cortadas , Lactação , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase , Transdução de Sinais
9.
Open Forum Infect Dis ; 10(1): ofac705, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36686636

RESUMO

Peritoneal histoplasmosis is a rare entity with few cases reported in the literature. We present a case of isolated acute peritoneal histoplasmosis that mimicked an advanced ovarian malignancy in a patient undergoing antitumor necrosis factor therapy for rheumatoid arthritis. We also reviewed the literature on Histoplasma peritonitis.

10.
Cancers (Basel) ; 15(23)2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38067393

RESUMO

The aim of this study was to examine the cytogenetic profiles of plasma cell neoplasms (PCNs) at various disease stages, encompassing 1087 patients with monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM), newly diagnosed multiple myeloma (NDMM), and refractory/relapsed multiple myeloma (RRMM). Fluorescence in situ hybridization (FISH) analyses were conducted on highly purified plasma cell samples, revealing that 96% of patients exhibited at least one cytogenetic abnormality. The genomic complexity escalated from MGUS to SMM and further to NDMM and RRMM, largely driven by 1q gain, del(17p), MYC-rearrangement (MYC-R), del(1p), and tetraploidy. Elevated frequencies of high-risk cytogenetics (59%), 1q gain (44%), and del(17p) (23%), as well as the presence of subclones (48%), were particularly notable in RRMM cases. IGH::CCND1 was observed in 26% of the cases, with no apparent variations across races, ages, or disease groups. Concurrent chromosomal analysis with FISH revealed that the incidence of abnormal karyotypes was strongly correlated with the extent of neoplastic plasma cell infiltration, genomic complexity, and the presence of specific abnormalities like del(17p) and MYC-R. Approximately 98% of the cases with abnormal karyotypes were complex, with most featuring five or more abnormalities. Chromosome 1 structural abnormalities were the most prevalent, found in 65% of cases. The frequent presence of subclones and composite karyotypes underscored the genomic heterogeneity and instability in this cohort.

11.
Cancers (Basel) ; 15(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36672407

RESUMO

MECOM rearrangement (MECOM-R) resulting from 3q26.2 aberrations is often associated with myeloid neoplasms and inferior prognosis in affected patients. Uncommonly, certain 3q26.2/MECOM-R can be subtle/cryptic and consequently overlooked by karyotyping. We identified 17 acute myeloid leukemia (AML) patients (male/female: 13/4 with a median age of 67 years, range 42 to 85 years) with a pericentric inv(3) leading to MECOM-R, with breakpoints at 3p23 (n = 11), 3p25 (n = 3), 3p21 (n = 2) and 3p13 (n = 1) on 3p and 3q26.2 on 3q. These pericentric inv(3)s were overlooked by karyotyping initially in 16 of 17 cases and later detected by metaphase FISH analysis. Similar to the patients with classic/paracentric inv(3)(q21q26.2), patients with pericentric inv(3) exhibited frequent cytopenia, morphological dysplasia (especially megakaryocytes), -7/del(7q), frequent NRAS (n = 6), RUNX1 (n = 5) and FLT-3 (n = 4) mutations and dismal outcomes (median overall survival: 14 months). However, patients with pericentric inv(3) more frequently had AML with thrombocytopenia (n = 15, 88%), relative monocytosis in peripheral blood (n = 15, 88%), decreased megakaryocytes (n = 11, 65%), and lower SF3B1 mutation. We conclude that AML with pericentric inv(3) shares some similarities with AML associated with classic/paracentric inv(3)/GATA2::MECOM but also shows certain unique features. Pericentric inv(3)s are often subtle/cryptic by chromosomal analysis. A reflex FISH analysis for MECOM-R is recommended in myeloid neoplasms showing -7/del(7q).

12.
Curr Opin Hematol ; 17(1): 31-5, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19881346

RESUMO

PURPOSE OF REVIEW: Neutrophil survival is regulated by a complex convergence of different pathways. The present review analyzes these pathways and discusses how neutrophil survival is modulated during the course of inflammatory reactions. RECENT FINDINGS: Although apoptosis appears to be the predominant cell death pathway in the neutrophil, recent data reveal that neutrophil survival is also regulated by a number of nonconventional pathways including NETosis, autophagic cell death, and other less characterized mechanisms. This supports an even more complex picture of the mechanisms involved in the regulation of neutrophil survival than previously thought. SUMMARY: The control of neutrophil survival is central to homoeostasis and resolution of inflammation. Cell death is usually discussed dichotomously in terms of apoptosis or necrosis. There are two main pathways responsible for the stimulation of apoptosis; a death receptor pathway triggered by Fas, tumor necrosis factor alpha, and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and a mitochondrial pathway stimulated by a number of stressors such as DNA damage, growth factor deprivation, and chemotherapy drugs. Nonconventional pathways of neutrophil death include NETosis and autophagic cell death as well as a number of poorly characterized mechanisms. Understanding the integrated pathways responsible for the control of neutrophil survival holds therapeutic promise in infectious and inflammatory diseases.


Assuntos
Neutrófilos/fisiologia , Animais , Apoptose , Sobrevivência Celular/fisiologia , Humanos , Mitocôndrias/fisiologia , Neutrófilos/imunologia , Transdução de Sinais
13.
J Cell Biochem ; 110(4): 857-65, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20564184

RESUMO

It has been reported that expression of tumor necrosis factor superfamily members occur at the onset of the mammary gland post-lactational involution. One of these proteins, tumor necrosis factor alpha (TNFalpha), is a major mediator of inflammation that is able to induce expression of several cytokines. Leukemia inhibitory factor (LIF) is an inflammatory cytokine that is induced and plays a fundamental role during post-lactational involution of the mammary gland. Therefore, our goal was to determine whether TNFalpha activity in the mammary epithelium might include regulation of LIF expression. This biological role would increase the significance of TNFalpha expression at the end of lactation. Our results show that TNFalpha was able to induce LIF transcription through ERK1/2 activation in a non-tumorigenic mouse mammary epithelial cell line, SCp2. We found that activation of TNFalpha receptor-2 (TNFR2) was specifically involved in triggering this signaling pathway. In addition, our data suggest the participation of AP-1 transcription factor family members in this pathway. We determined that TNFalpha treatment induced c-fos transcription, and blocking AP-1 activity resulted in a significant inhibition of TNFalpha-induced LIF expression. Finally, we found that TNFalpha was also able to trigger LIF expression and ERK1/2 activation in the mouse mammary gland in vivo. Therefore, our data suggest that TNFalpha may contribute to mammary gland involution by, among other activities, eliciting LIF expression through ERK1/2 and AP1 activation.


Assuntos
Fator Inibidor de Leucemia/metabolismo , Glândulas Mamárias Humanas/enzimologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fator de Necrose Tumoral alfa/fisiologia , Animais , Western Blotting , Linhagem Celular , Ensaio de Desvio de Mobilidade Eletroforética , Ativação Enzimática , Humanos , Imuno-Histoquímica , Glândulas Mamárias Humanas/citologia , Camundongos , Camundongos Endogâmicos BALB C , Fator de Transcrição AP-1/metabolismo
14.
Lab Invest ; 90(7): 1049-59, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20368700

RESUMO

Neutrophils are short-lived cells that rapidly undergo apoptosis. However, their survival can be regulated by signals from the environment. Flagellin, the primary component of the bacterial flagella, is known to induce neutrophil activation. In this study we examined the ability of flagellin to modulate neutrophil apoptosis. Neutrophils cultured for 12 and 24 h in the presence of flagellin from Salmonella typhimurium at concentrations found in pathological situations underwent a marked prevention of apoptosis. In contrast, Helicobacter pylori flagellin did not affect neutrophil survival, suggesting that Salmonella flagellin exerts the antiapoptotic effect by interacting with TLR5. The delaying in apoptosis mediated by Salmonella flagellin was coupled to higher expression levels of the antiapoptotic protein Mcl-1 and lower levels of activated caspase-3. Analysis of the signaling pathways indicated that Salmonella flagellin induced the activation of the p38 and ERK1/2 MAPK pathways as well as the PI3K/Akt pathway. Furthermore, it also stimulated IkappaBalpha degradation and the phosphorylation of the p65 subunit, suggesting that Salmonella flagellin also triggers NF-kappaB activation. Moreover, the pharmacological inhibition of ERK1/2 pathway and NF-kappaB activation partially prevented the antiapoptotic effects exerted by flagellin. Finally, the apoptotic delaying effect exerted by flagellin was also evidenced when neutrophils were cultured with whole heat-killed S. typhimurium. Both a wild-type and an aflagellate mutant S. typhimurium strain promoted neutrophil survival; however, when cultured in low bacteria/neutrophil ratios, the flagellate bacteria showed a higher capacity to inhibit neutrophil apoptosis, although both strains showed a similar ability to induce neutrophil activation. Taken together, our results indicate that flagellin delays neutrophil apoptosis by a mechanism partially dependent on the activation of ERK1/2 MAPK and NF-kappaB. The ability of flagellin to delay neutrophil apoptosis could contribute to perpetuate the inflammation during infections with flagellated bacteria.


Assuntos
Apoptose/efeitos dos fármacos , Flagelina/farmacologia , Neutrófilos/efeitos dos fármacos , Caspase 3/metabolismo , Sobrevivência Celular , Células Cultivadas , Flagelos/fisiologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteína de Sequência 1 de Leucemia de Células Mieloides , NF-kappa B/metabolismo , Neutrófilos/enzimologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Infecções por Salmonella/imunologia , Salmonella typhimurium/fisiologia
15.
J Pharmacol Exp Ther ; 334(3): 854-62, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20516139

RESUMO

Dendritic cells (DC) are highly specialized antigen-presenting cells with a unique ability to activate resting T lymphocytes and initiate primary immune responses. Angiotensin II (AII) is involved in key events of the inflammatory response. Because our previous work implicated an effect of AII on differentiation and function of murine and human DC, we investigated the impact of AII type 1 receptor (AT(1)) deficiency on the phenotypical and functional properties of mouse DC in vitro and in vivo. Bone marrow (BM) cells isolated from mice lacking AII subtype 1a receptor (AT(1a)), AII subtype 1b receptor (AT(1b)), or both receptor isoforms and control littermates [wild type (WT)] were cultured for 7 days in the presence of recombinant mouse granulocyte/macrophage colony-stimulating factor to generate myeloid DC in vitro. Generation of CD11c(+) cells was less efficient in both AT(1a)- and AT(1b)-deficient BM cells than in WT BM cell cultures. Moreover, DC generated from AT(1)-deficient progenitors showed lower levels of expression of major histocompatibility complex II (MHC-II) and CD11c (p < 0.01) and a marked reduction in their allostimulatory activity (p < 0.01 or 0.001). Although AT(1)-deficient DC released comparable levels of interleukin (IL)-10 and IL-12p70 to WT DC, they produced significantly lower levels of tumor necrosis factor alpha (TNF-alpha) (p < 0.05). Remarkably, CD11c(+) cells isolated from the spleen of AT(1) knockout mice challenged with lipopolysaccharide in vivo up-regulated MHC-II, CD40, and CD80 as did WT, but released significantly lower levels of TNF-alpha (p < 0.01). These data provide clear evidence that AT(1) controls differentiation and functionality of DC and thus may have a crucial impact on inflammatory processes where local angiotensinergic systems are known to be activated.


Assuntos
Células Dendríticas/fisiologia , Receptor Tipo 1 de Angiotensina/genética , Animais , Western Blotting , Antígeno CD11c/metabolismo , Separação Celular , Citocinas/metabolismo , Células Dendríticas/ultraestrutura , Endocitose , Citometria de Fluxo , Genes MHC da Classe II/genética , Genótipo , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor Tipo 1 de Angiotensina/deficiência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Baço/citologia , Linfócitos T/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
16.
Cytokine Growth Factor Rev ; 18(1-2): 5-17, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17321783

RESUMO

Dendritic cells (DCs) are the only antigen-presenting cell capable of activating naïve T lymphocytes, and hence they play a crucial role in the induction of adaptive immunity. Immature DCs sample and process antigens, and efficiently sense a large variety of signals from the surrounding environment. Upon activation, they become capable to activate naïve T cells and to direct the differentiation and polarization of effector T lymphocytes. It is becoming increasingly clear that different signals are able to determine distinct programs of DC differentiation and different forms of immunity and tolerance. In the past few years many advances have been made in addressing the action exerted by pathogen-associated molecular patterns (PAMPs), cytokines, chemokines, and other less characterized stress molecules on the activity of DCs. In this review we focus on the multiplicity of innate signals able to modulate the functional profile of DCs.


Assuntos
Apresentação de Antígeno/imunologia , Diferenciação Celular/imunologia , Citocinas/imunologia , Células Dendríticas/imunologia , Transdução de Sinais/imunologia , Animais , Humanos , Tolerância Imunológica , Imunidade Inata , Ativação Linfocitária/imunologia , Estresse Fisiológico/imunologia , Linfócitos T/imunologia
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