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1.
Adv Sci (Weinh) ; 11(15): e2308200, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342623

RESUMO

Realizing efficient energy utilization from the heat source of the sun and the cold source of outer space is of great significance for addressing the global energy and environmental crisis. Materials with ideal full-spectrum solar absorption and infrared emission are highly desirable for adapting to the continuous weather dynamic throughout the day, nonetheless, their development remains challenging. Here, a polymer nanocomposite with full-spectrum strong solar (280-2500 nm) absorption ranging from 88.8% to 94.8% with an average value of 93.2% and full-spectrum high infrared (8-13 µm) emission ranging from 81.3% to 90.0% with an average value of 84.2%, is reported by melt-processing polypropylene and uniformly dispersed low-loading MXene nanosheets (1.9 vol%). The nanocomposite can achieve daytime photothermal enhancement of ≈50 °C and nighttime radiative cooling of 8 °C. The temperature difference throughout the day ensures all-day uninterrupted thermoelectric generation, yielding a power density output of 1.5 W m-2 (daytime) and 7.9 mW m-2 (nighttime) in real outdoor environment without any additional energy consumption. This work provides an impressive polymer nanocomposite with ideal full-spectrum solar absorption and infrared emission for all-day uninterrupted thermal energy management and conversion.

3.
J Immunol ; 199(7): 2536-2546, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28814601

RESUMO

IL-15 is an essential cytokine known to promote T cell survival and activate the effector function of memory phenotype CD8 T cells. Blocking IL-15 signals also significantly impacts tissue-specific effector and memory CD8 T cell formation. In this study, we demonstrate that IL-15 influences the generation of memory CD8 T cells by first promoting their accumulation into mucosal tissues and second by sustaining expression of Bcl-6 and T-bet. We show that the mechanism for this recruitment is largely dependent on mammalian target of rapamycin and its subsequent inactivation of FoxO1. Last, we show that IL-15 complexes delivered locally to mucosal tissues without reinfection is an effective strategy to enhance establishment of tissue resident memory CD8 T cells within mucosal tissues. This study provides mechanistic insight into how IL-15 controls the generation of memory CD8 T cells and influences their trafficking and ability to take up residence within peripheral tissues.


Assuntos
Linfócitos T CD8-Positivos/fisiologia , Memória Imunológica , Interleucina-15/fisiologia , Mucosa/imunologia , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Movimento Celular , Proteína Forkhead Box O1/metabolismo , Interleucina-15/genética , Interleucina-15/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Mucosa/citologia , Mucosa/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-6/genética , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Proteínas com Domínio T/genética , Subpopulações de Linfócitos T/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
4.
Nat Med ; 23(1): 100-106, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27941791

RESUMO

Excess levels of protein in urine (proteinuria) is a hallmark of kidney disease that typically occurs in conjunction with diabetes, hypertension, gene mutations, toxins or infections but may also be of unknown cause (idiopathic). Systemic soluble urokinase plasminogen activator receptor (suPAR) is a circulating factor implicated in the onset and progression of chronic kidney disease (CKD), such as focal segmental glomerulosclerosis (FSGS). The cellular source(s) of elevated suPAR associated with future and progressing kidney disease is unclear, but is likely extra-renal, as the pathological uPAR is circulating and FSGS can recur even after a damaged kidney is replaced with a healthy donor organ. Here we report that bone marrow (BM) Gr-1lo immature myeloid cells are responsible for the elevated, pathological levels of suPAR, as evidenced by BM chimera and BM ablation and cell transfer studies. A marked increase of Gr-1lo myeloid cells was commonly found in the BM of proteinuric animals having high suPAR, and these cells efficiently transmit proteinuria when transferred to healthy mice. In accordance with the results seen in suPAR-associated proteinuric animal models, in which kidney damage is caused not by local podocyte-selective injury but more likely by systemic insults, a humanized xenograft model of FSGS resulted in an expansion of Gr-1lo cells in the BM, leading to high plasma suPAR and proteinuric kidney disease. Together, these results identify suPAR as a functional connection between the BM and the kidney, and they implicate BM immature myeloid cells as a key contributor to glomerular dysfunction.


Assuntos
Glomerulosclerose Segmentar e Focal/metabolismo , Células Mieloides/metabolismo , Proteinúria/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Insuficiência Renal Crônica/metabolismo , Transferência Adotiva , Animais , Células da Medula Óssea , Modelos Animais de Doenças , Glomérulos Renais/metabolismo , Camundongos , Camundongos Knockout , Camundongos SCID , Camundongos Transgênicos
5.
J Matern Fetal Neonatal Med ; 30(24): 2951-2955, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27923319

RESUMO

BACKGROUND: This study aims to assess the diagnostic and prognostic value of Swansea criteria in diagnosing acute fatty liver of pregnancy (AFLP) in a Chinese population. METHODS: A retrospective study was conducted on 52 Chinese women diagnosed with AFLP. All selected cases were reassessed using the Swansea criteria with special focus on the noninvasive criteria, since performing a liver biopsy for this indication is rare in a Chinese population. RESULTS: Ninety point four percent of patients fulfilled five or more of the Swansea criteria. Thirty-one cases were positive for six or more Swansea criteria, but there were no significance differences between patients when using a cutoff criteria <6 or >6. When patients were positive for less than seven criteria, frequency of stillbirth, continuous blood purification (CBP) treatment, hysterectomy, and postpartum hemorrhage were not increased. However, patients who were positive for seven or more criteria had a significantly higher risk of stillbirth and a higher rate of CBP treatment (p < 0.05). Areas under the receiver operating characteristic (ROC) curve of postpartum hemorrhage was 0.670, which reached a statistical significance (p = 0.040). We observed a significantly elevated postpartum hemorrhage along with positivity of the Swansea criteria (p = 0.040). CONCLUSIONS: Swansea criteria without liver biopsy are good screening tools for AFLP diagnosis, and may be useful for assessing disease severity.


Assuntos
Fígado Gorduroso/diagnóstico , Medicina Tradicional Chinesa/métodos , Complicações na Gravidez/diagnóstico , Diagnóstico Pré-Natal/métodos , Adulto , China , Diagnóstico Diferencial , Diagnóstico Precoce , Feminino , Idade Gestacional , Humanos , Testes de Função Hepática/métodos , Gravidez , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
6.
J Immunol ; 187(9): 4900-6, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21948985

RESUMO

The efficacy of B cell-depletion therapy in rheumatoid arthritis has driven interest in understanding the mechanism. Because the decrease in autoantibodies in rheumatoid arthritis does not necessarily correlate with clinical outcome, other mechanisms may be operative. We previously reported that in proteoglycan-induced arthritis (PGIA), B cell-depletion inhibits autoreactive T cell responses. Recent studies in B cell-depletion therapy also indicate a role for B cells in suppressing regulatory mechanisms. In this study, we demonstrate that B cells inhibited both the expansion and function of T regulatory (Treg) cells in PGIA. Using an anti-CD20 mAb, we depleted B cells from mice with PGIA and assessed the Treg cell population. Compared to control Ab-treated mice, Treg cell percentages were elevated in B cell-depleted mice, with a higher proportion of CD4(+) T cells expressing Foxp3 and CD25. On a per-cell basis, CD4(+)CD25(+) cells from B cell-depleted mice expressed increased amounts of Foxp3 and were significantly more suppressive than those from control Ab-treated mice. The depletion of Treg cells with an anti-CD25 mAb concurrent with B cell-depletion therapy restored the severity of PGIA to levels equal to untreated mice. Although titers of autoantibodies did not recover to untreated levels, CD4(+) T cell recall responses to the immunizing Ag returned as measured by T cell proliferation and cytokine production. Thus, B cells have the capacity to regulate inflammatory responses by enhancing effector T cells along with suppressing Treg cells.


Assuntos
Artrite Experimental/imunologia , Artrite Experimental/prevenção & controle , Subpopulações de Linfócitos B/imunologia , Depleção Linfocítica , Linfopenia/imunologia , Linfopenia/patologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Animais , Artrite Experimental/patologia , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Artrite Reumatoide/prevenção & controle , Subpopulações de Linfócitos B/patologia , Epitopos de Linfócito T/imunologia , Feminino , Inflamação/imunologia , Inflamação/patologia , Depleção Linfocítica/métodos , Linfopenia/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Proteoglicanas/administração & dosagem , Proteoglicanas/imunologia , Proteoglicanas/toxicidade , Índice de Gravidade de Doença , Linfócitos T Reguladores/patologia
7.
Eur J Immunol ; 40(11): 3117-27, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21061440

RESUMO

The immune system has developed several regulatory mechanisms to maintain homeostasis of adaptive immune responses. T-cell programmed death (PD)-1 recognition of B7-H1 (PD-L1) expressed on APC and non-lymphoid tissue regulates T-cell activation. We show that B7-H1(-/-) mice exhibit exacerbated proteoglycan (PG)-induced arthritis and increased Th-1 CD4(+) T-cell responses. Unexpectedly, the PG-specific antibody response in B7-H1(-/-) mice was diminished. A reduction in the number of peanut agglutinin(+) GC coincided with a decrease in CD19(+) GL-7(+) CD95(+) GC B cells that was a result of increased caspase-induced apoptosis. The percent of CD38(+) CD138(+) emerging plasma cells was decreased. B7-H1(-/-) mice exhibited an increased frequency of CD4(+) PD-1(hi) CXCR5(hi) ICOS(hi) CD62L(lo) T follicular helper cells that displayed a hyperactive phenotype with increased expression of mRNA transcripts for Bcl6, IL-21, and the apoptosis-inducer molecule FasL. In cell transfer of B7-H1(-/-) cells into SCID mice, non-B and non-T cells were sufficient to normalize the antibody response, T-cell hyperactivity, and the development of PG-induced arthritis. These findings indicate that B7-H1 on non-B and non-T cells signals through PD-1 on T effector cells to prevent excessive activation and reduce autoimmune arthritis. Furthermore, these findings demonstrate a novel role for B7-H1 expression in promoting B-cell survival by regulating the activation of T follicular helper cell.


Assuntos
Artrite Experimental/imunologia , Artrite Reumatoide/imunologia , Antígeno B7-1/imunologia , Glicoproteínas de Membrana/imunologia , Peptídeos/imunologia , Plasmócitos/imunologia , Transdução de Sinais/imunologia , Células Th1/imunologia , Animais , Formação de Anticorpos/genética , Formação de Anticorpos/imunologia , Antígenos de Diferenciação/biossíntese , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/imunologia , Antígenos de Diferenciação/metabolismo , Artrite Experimental/genética , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Antígeno B7-1/genética , Antígeno B7-1/metabolismo , Antígeno B7-H1 , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/imunologia , Interleucinas/genética , Interleucinas/imunologia , Interleucinas/metabolismo , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Camundongos SCID , Peptídeos/genética , Peptídeos/metabolismo , Plasmócitos/metabolismo , Plasmócitos/patologia , Receptor de Morte Celular Programada 1 , Proteínas Proto-Oncogênicas c-bcl-6 , Transdução de Sinais/genética , Células Th1/metabolismo , Células Th1/patologia
8.
J Immunol ; 181(1): 329-37, 2008 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18566398

RESUMO

IL-17 is the hallmark cytokine for the newly identified subset of Th cells, Th17. Th17 cells are important instigators of inflammation in several models of autoimmune disease; in particular, collagen induced arthritis (CIA) and experimental autoimmune encephalomyelitis (EAE), which were previously characterized as Th1-mediated diseases. Although high levels of IFN-gamma are secreted in CIA and EAE, disease is exacerbated in IFN-gamma- or IFN-gamma receptor-deficient mice due to the ability of IFN-gamma to suppress IL-17 secretion. However, in proteoglycan-induced arthritis (PGIA), severe arthritis is dependent on the production of IFN-gamma. We were therefore interested in determining the role of IL-17 in PGIA. We assessed the progression of arthritis in IL-17-deficient (IL-17-/-) mice and found the onset and severity of arthritis were equivalent in wild-type (WT) and IL-17-/- mice. Despite evidence that IL-17 is involved in neutrophil recruitment, synovial fluid from arthritic joints showed a comparable proportion of Gr1+ neutrophils in WT and IL-17-/- mice. IL-17 is also implicated in bone destruction in autoimmune arthritis, however, histological analysis of the arthritic joints from WT and IL-17-/- mice revealed a similar extent of joint cellularity, cartilage destruction, and bone erosion despite significantly reduced RANKL (receptor activator of NK-kappaB ligand) expression. There were only subtle differences between WT and IL-17-/- mice in proinflammatory cytokine expression, T cell proliferation, and autoantibody production. These data demonstrate that IL-17 is not absolutely required for autoimmune arthritis and that the production of other proinflammatory mediators is sufficient to compensate for the loss of IL-17 in PGIA.


Assuntos
Artrite/metabolismo , Interleucina-17/metabolismo , Proteoglicanas/farmacologia , Animais , Artrite/induzido quimicamente , Artrite/imunologia , Artrite/patologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Doenças Ósseas/genética , Doenças Ósseas/metabolismo , Doenças Ósseas/patologia , Humanos , Interferon gama/deficiência , Interferon gama/genética , Interferon gama/metabolismo , Interleucina-12/deficiência , Interleucina-12/genética , Interleucina-12/metabolismo , Interleucina-17/deficiência , Interleucina-17/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Ligante RANK/metabolismo , Baço/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transcrição Gênica/genética
9.
J Immunol ; 180(7): 4994-5003, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18354225

RESUMO

B cells have been implicated in the pathogenesis of rheumatoid arthritis (RA) since the discovery of RA as an autoimmune disease. There is renewed interest in B cells in RA based on the clinical efficacy of B cell depletion therapy in RA patients. Although, reduced titers of rheumatoid factor and anti-cyclic citrullinated peptide Abs are recorded, the mechanisms that convey clinical improvement are incompletely understood. In the proteoglycan-induced arthritis (PGIA) mouse model of RA, we reported that Ag-specific B cells have two important functions in the development of arthritis. PG-specific B cells are required as autoantibody-producing cells as well as Ag-specific APCs. Herein we report on the effects of anti-CD20 mAb B cell depletion therapy in PGIA. Mice were sensitized to PG and treated with anti-CD20 Ab at a time when PG-specific autoantibodies and T cell activation were evident but before acute arthritis. In mice treated with anti-CD20 mAb, development of arthritis was significantly reduced in comparison to control mAb-treated mice. B cell depletion reduced the PG-specific autoantibody response. Furthermore, there was a significant reduction in the PG-specific CD4(+) T cell recall response as well as significantly fewer PG-specific CD4(+) T cells producing IFN-gamma and IL-17, but not IL-4. The reduction in PG-specific T cells was confirmed by the inability of CD4(+) T cells from B cell-depleted mice to adoptively transfer disease into SCID mice. Overall, B cell depletion during PGIA significantly reduced disease and inhibited both autoreactive B cell and T cell function.


Assuntos
Antígenos CD20/imunologia , Artrite Reumatoide/imunologia , Artrite Reumatoide/terapia , Autoanticorpos/imunologia , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Proteoglicanas/farmacologia , Transferência Adotiva , Animais , Anticorpos Monoclonais/imunologia , Artrite Reumatoide/induzido quimicamente , Artrite Reumatoide/patologia , Células Cultivadas , Feminino , Imunoterapia , Camundongos
10.
J Immunol ; 179(8): 5109-16, 2007 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17911596

RESUMO

Depletion of B cells in rheumatoid arthritis is therapeutically efficacious. Yet, the mechanism by which B cells participate in the inflammatory process is unclear. We previously demonstrated that Ag-specific B cells have two important functions in the development of arthritis in a murine model of rheumatoid arthritis, proteoglycan (PG)-induced arthritis (PGIA). PG-specific B cells function as autoantibody-producing cells and as APCs that activate PG-specific T cells. Moreover, the costimulatory molecule CD86 is up-regulated on PG-specific B cells in response to stimulation with PG. To address the requirement for CD80/CD86 expression on B cells in the development of PGIA, we generated mixed bone marrow chimeras in which CD80/CD86 is specifically deleted on B cells and not on other APC populations. Chimeras with a specific deficiency in CD80/CD86 expression on B cells are resistant to the induction of PGIA. The concentration of PG-specific autoantibody is similar in mice sufficient or deficient for CD80/86-expressing B cells, which indicates that resistance to PGIA is not due to the suppression of PG-specific autoantibody production. CD80/86-deficient B cells failed to effectively activate PG-specific autoreactive T cells as indicated by the failure of T cells from PG-immunized CD80/86-deficient B cell chimeras to transfer arthritis into SCID mice. In vitro secondary recall responses to PG are also dependent on CD80/86-expressing B cells. These results demonstrate that a CD80/86:CD28 costimulatory interaction between B cells and T cells is required for autoreactive T cell activation and the induction of arthritis but not for B cell autoantibody production.


Assuntos
Artrite Reumatoide/imunologia , Autoantígenos/imunologia , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/metabolismo , Antígeno B7-1/biossíntese , Antígeno B7-2/biossíntese , Ativação Linfocitária/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Artrite Reumatoide/genética , Autoanticorpos/biossíntese , Antígeno B7-1/genética , Antígeno B7-1/fisiologia , Antígeno B7-2/genética , Antígeno B7-2/fisiologia , Feminino , Imunidade Inata/genética , Ativação Linfocitária/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Camundongos SCID , Proteoglicanas/administração & dosagem , Proteoglicanas/imunologia , Quimera por Radiação , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/transplante
11.
J Control Release ; 120(3): 186-94, 2007 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-17582643

RESUMO

A novel copolymer, poly(N-isopropylacrylamide)-chitosan (PNIPAAm-CS), was investigated for its thermosensitive in situ gel-forming properties and potential utilization for ocular drug delivery. The thermal sensitivity and low critical solution temperature (LCST) were determined by the cloud point method. PNIPAAm-CS had a LCST of 32 degrees C, which is close to the surface temperature of the eye. The in vivo ocular pharmacokinetics of timolol maleate in PNIPAAm-CS solution were evaluated and compared to that in conventional eye drop solution by using rabbits according to the microdialysis method. The C(max) of timolol maleate in aqueous fluid for the PNIPAAm-CS solution was 11.2 microg/ml, which is two-fold higher than that of the conventional eye drop, along with greater AUC. Furthermore, the PNIPAAm-CS gel-forming solution of timolol maleate had a stronger capacity to reduce the intra-ocular pressure (IOP) than that of the conventional eye drop of same concentration over a period of 12 h. In addition, the MTT assay showed that there is little cytotoxicity of PNIPAAm-CS at concentration range of 0.5-400 microg/ml. These results suggest that PNIPAAm-CS is a potential thermosensitive in situ gel-forming material for ocular drug delivery, and it may improve the bio-availability, efficacy, and compliance of some eye drugs.


Assuntos
Acrilamidas/química , Quitosana/química , Córnea/metabolismo , Sistemas de Liberação de Medicamentos , Géis , Polímeros/química , Resinas Acrílicas , Antagonistas Adrenérgicos beta/farmacocinética , Animais , Área Sob a Curva , Células Cultivadas , Córnea/citologia , Relação Dose-Resposta a Droga , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Formazans/metabolismo , Masculino , Microdiálise , Soluções Oftálmicas/química , Soluções Oftálmicas/farmacocinética , Transição de Fase , Polímeros/síntese química , Polímeros/farmacologia , Coelhos , Temperatura , Sais de Tetrazólio/metabolismo , Timolol/farmacocinética , Viscosidade
12.
Arthritis Rheum ; 56(3): 861-70, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17330244

RESUMO

OBJECTIVE: Interleukin-4 (IL-4) is an antiinflammatory cytokine that inhibits the onset and severity of proteoglycan-induced arthritis (PGIA). To distinguish the role of IL-4 in the innate immune response versus the adaptive immune response, we generated mice with a specific deletion of the IL-4 receptor alpha-chain (IL-4Ralpha) in macrophages and neutrophils. METHODS: To obtain mice in which IL-4Ralpha is deleted in macrophages and neutrophils, we intercrossed mice carrying a loxP-flanked (floxed) IL-4Ralpha allele and Cre recombinase expressed under control of the regulatory region for the lysozyme M gene (LysM(cre) mice) with conditional IL-4Ralpha(flox/flox) mice and then mated them to complete IL-4Ralpha(-/-) mice to obtain hemizygous LysM(cre)IL-4Ralpha(flox/-) mice. LysM(cre)-negative IL-4Ralpha(flox/-) mice (IL-4Ralpha(flox/-) mice) were used as control mice. PGIA was induced by immunization with human PG in adjuvant. The onset, incidence, and severity of arthritis were monitored over time. Levels of proinflammatory cytokines were measured in the sera of PG-immunized mice, and cytokine and chemokine transcripts were measured in joints. RESULTS: The severity of PGIA was exacerbated in IL-4Ralpha(-/-) and LysM(cre)IL-4Ralpha(flox/-) mice in comparison with control (IL-4Ralpha(flox/-)) mice. The increase in arthritis susceptibility in IL-4Ralpha(-/-) and LysM(cre)IL-4Ralpha(flox/-) mice correlated with elevated serum levels of the proinflammatory cytokines IL-1beta and IL-6 and with elevated cytokine (IL-1beta and IL-6) and chemokine (macrophage inflammatory protein 1alpha [MIP-1alpha] and MIP-2) transcripts from joints. However, arthritis susceptibility did not correlate with IL-2 or interferon-gamma (IFNgamma) concentrations or with PG-specific antibody IgG2a isotype, since levels of IL-2, IFNgamma, or PG-specific antibody IgG2a isotype in control (IL-4Ralpha(flox/-)) and LysM(cre)IL-4Ralpha(flox/-) mice were reduced in comparison with those in IL-4Ralpha(-/-) mice. CONCLUSION: These findings indicate that IL-4 functions as a major antiinflammatory cytokine in PGIA by governing the activity of macrophages/neutrophils and less so by controlling T cell activity and autoantibody isotype expression.


Assuntos
Artrite Reumatoide/fisiopatologia , Imunidade Inata/fisiologia , Interleucina-4/fisiologia , Animais , Artrite Reumatoide/induzido quimicamente , Feminino , Regulação da Expressão Gênica , Interleucina-1beta/sangue , Interleucina-4/genética , Interleucina-6/sangue , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Knockout , Proteoglicanas , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/fisiologia , Índice de Gravidade de Doença
13.
Cancer Res ; 64(24): 8911-8, 2004 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-15604252

RESUMO

Retinoids regulate gene transcription through activating retinoic acid receptors (RARs)/retinoic X receptors (RXRs). Of the three RAR receptors (alpha, beta, and gamma), RARbeta has been considered a tumor suppressor gene. Here, we identified a novel RARbeta isoform-RARbeta5 in breast epithelial cells, which could play a negative role in RARbeta signaling. Similar to RARbeta2, the first exon (59 bp) of RARbeta5 is RARbeta5 isoform specific, whereas the other exons are common to all of the RARbeta isoforms. The first exon of RARbeta5 does not contain any translation start codon, and therefore its protein translation begins at an internal methionine codon of RARbeta2, lacking the A, B, and part of C domain of RARbeta2. RARbeta5 protein was preferentially expressed in estrogen receptor-negative breast cancer cells and normal breast epithelial cells that are relatively resistant to retinoids, whereas estrogen receptor-positive cells that did not express detectable RARbeta5 protein were sensitive to retinoid treatment, suggesting that this isoform may affect the cellular response to retinoids. RARbeta5 isoform is unique among all of the RARs, because a corresponding isoform was not detectable for either RARalpha or RARgamma. RARbeta5 mRNA was variably expressed in normal and cancerous breast epithelial cells. Its transcription was under the control of a distinct promoter P3, which can be activated by all-trans-retinoic acid (atRA) and other RAR/RXR selective retinoids in MCF-7 and T47D breast cancer cells. We mapped the RARbeta5 promoter and found a region -302/-99 to be the target region of atRA. In conclusion, we identified and initially characterized RARbeta5 in normal, premalignant, and malignant breast epithelial cells. RARbeta5 may serve as a potential target of retinoids in prevention and therapy studies.


Assuntos
Neoplasias da Mama/genética , Receptores do Ácido Retinoico/genética , Tretinoína/farmacologia , Sequência de Aminoácidos , Sequência de Bases , Mama/metabolismo , Mama/fisiologia , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Clonagem Molecular , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Dados de Sequência Molecular , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Regiões Promotoras Genéticas , Isoformas de Proteínas , RNA Mensageiro/genética , Receptores do Ácido Retinoico/biossíntese , Transcrição Gênica , Transfecção
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