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1.
Rinsho Ketsueki ; 60(9): 1046-1055, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31597826

RESUMO

Human iPS cells are somatic cells reprogrammed to the pluripotent state. Because of their pluripotent nature, iPS cells are now commonly used to model several developmental processes including hematopoiesis in vitro. The in vitro models can be used to study the mechanisms regulating not only normal hematopoiesis but also hematological diseases ranging from monogenic congenital disorders to genetically multifactorial malignancies. Those disease models can also be used to investigate novel treatments through procedures including high throughput drug screening. The possible clinical applications of iPS cell-derived hematopoietic cells include immunotherapy with T lymphocytes, NK cells and macrophages, and transfusion therapy with platelets and red blood cells. Platelets have now been produced from iPS cells in quantities sufficient for clinical use. By developing expandable immortalized megakaryocyte cell lines (imMKCLs), several novel drugs and turbulence-incorporated bioreactors, efficient and scalable generation of platelets was achieved. This review summarizes the current status of iPS cell research in hematopoiesis with details on iPS cell-derived platelets.


Assuntos
Plaquetas/citologia , Terapia Baseada em Transplante de Células e Tecidos , Células-Tronco Pluripotentes Induzidas/citologia , Diferenciação Celular , Eritrócitos , Hematopoese , Humanos , Imunoterapia , Células Matadoras Naturais , Macrófagos , Megacariócitos , Linfócitos T
2.
Immunol Lett ; 211: 41-48, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31141702

RESUMO

Although immunomodulatory drugs (IMiDs) were originally developed as anti-inflammatory drugs, they are effective for multiple myeloma. In order to gain further insights into the immunomodulatory mechanisms of IMiDs for the treatment of inflammatory disorders and myeloma, we investigated the influence of a representative IMiD, lenalidomide, on human primary dendritic cell (DC) subsets: myeloid-derived CD1c+ DCs, CD141+ DCs, and plasmacytoid DCs. Lenalidomide did not affect the viability or expression of costimulatory molecules, but it potently suppressed the production of the key inflammatory cytokines IL-12 and IL-23, and enhanced the production of the anti-inflammatory cytokine IL-10 by CD1c+ DCs. Lenalidomide also suppressed the production of IFN-α by CD141+ DCs but not that by plasmacytoid DCs. Lenalidomide likely targets pathways downstream of the nuclear translocation of the transcription factors nuclear factor κB (NF-κB) and IFN regulatory 5 (IRF5) in CD1c+ DCs. Consistent with the direct immunomodulatory effects on DCs, lenalidomide decreased the capacity of CD1c+ DCs to induce differentiation of naïve CD4+ T cells into effector cells producing immune activating and myeloma-promoting cytokines. This study demonstrated that lenalidomide has anti-inflammatory effects via the modulation of cytokine production by human myeloid-derived DCs. Such effects on DCs may allow for beneficial immunomodulation aiding in the treatment of inflammatory disorders and multiple myeloma.

3.
Blood ; 133(16): 1700-1701, 2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-31000515
4.
Rinsho Ketsueki ; 59(10): 1905-1913, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-30305491

RESUMO

Platelet transfusion products derived from induced pluripotent stem cells (iPSCs) have been pursued as a blood donor-independent and genetically manipulative measure to complement or as an alternative to current platelet products. Platelets are enucleate blood cells indispensable for hemostasis. Thus, platelet transfusions have been clinically established to treat patients with severe thrombocytopenia. However, current blood products face issues in the balance of supply and demand, alloimmune responses, and infections and are expected to meet the shortage of donors in aging societies. iPSc-derived platelet products are qualitatively and quantitatively approaching a clinically applicable level, owing to advances and novel findings in expandable megakaryocyte cell lines, turbulence-incorporating bioreactors, and reagents that enable feeder cell-free production and improve platelet quality. Currently, the establishment of guidelines to assure the quality of iPSC-derived blood products for clinical application is in process. Considering the low risk of tumorigenicity and the large demand, ex vivo production of iPSC-derived platelets could lead to iPSC-based regenerative medicine becoming a common clinical practice and the development of a future system in which anyone can safely receive a platelet transfusion in their time of need.

5.
Blood Adv ; 2(17): 2262-2272, 2018 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-30206099

RESUMO

During maturation, megakaryocytes (MKs) express ß1-tubulin (TUBB1) and rearrange their microtubule components to enlarge, form proplatelets, and eventually release platelets. The development of a platform to identify in vitro conditions that would efficiently promote MK development could potentially enable large-scale platelet production. Here, we show that an immortalized MK cell line (imMKCL) genetically modified to express the ß1-tubulin-Venus reporter provides a practical system to efficiently monitor the in vitro production of platelet-like particles (PLPs). The Venus transgene was inserted downstream of the TUBB1 locus in imMKCLs using CRISPR/Cas9, and the expression was visualized by Venus fluorescence intensity. This imMKCL reporter line was then used for high-throughput drug screening. We identified several compounds that significantly improved the efficiency of PLP production in vitro under feeder-free conditions and showed a significant tendency to recover platelets in vivo in a mouse thrombocytopenia model induced by anti-GPIbα antibody administration. Interestingly, most of these compounds, including a WNT signaling pathway inhibitor, Wnt-C59, antagonized the aryl hydrocarbon receptor (AhR) to increase PLP production, confirming the crucial role of AhR inhibition in MK maturation. Consistently, small interfering RNA treatment against AhR increased the Venus intensity and PLP production. TCS 359, an FLT3 inhibitor, significantly increased PLP production independently of FLT3 or AhR. This study highlights the usefulness of the ß1-tubulin reporter MK line as a useful tool to study the mechanisms underlying thrombopoiesis and to identify novel inducers of ex vivo platelet production.

6.
Cell ; 174(3): 636-648.e18, 2018 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-30017246

RESUMO

The ex vivo generation of platelets from human-induced pluripotent cells (hiPSCs) is expected to compensate donor-dependent transfusion systems. However, manufacturing the clinically required number of platelets remains unachieved due to the low platelet release from hiPSC-derived megakaryocytes (hiPSC-MKs). Here, we report turbulence as a physical regulator in thrombopoiesis in vivo and its application to turbulence-controllable bioreactors. The identification of turbulent energy as a determinant parameter allowed scale-up to 8 L for the generation of 100 billion-order platelets from hiPSC-MKs, which satisfies clinical requirements. Turbulent flow promoted the release from megakaryocytes of IGFBP2, MIF, and Nardilysin to facilitate platelet shedding. hiPSC-platelets showed properties of bona fide human platelets, including circulation and hemostasis capacities upon transfusion in two animal models. This study provides a concept in which a coordinated physico-chemical mechanism promotes platelet biogenesis and an innovative strategy for ex vivo platelet manufacturing.

7.
Rinsho Ketsueki ; 58(10): 2150-2159, 2017.
Artigo em Japonês | MEDLINE | ID: mdl-28978860

RESUMO

Blood products derived from iPS cells have been pursued as a blood donor-independent and genetically manipulative measure to complement or alternate current transfusion products. Erythrocytes and platelets are anucleate blood cells that are indispensable for oxygen delivery and hemostasis, respectively. Consequently, blood transfusions have been clinically established to treat severe anemia and thrombocytopenia. However, current blood products exhibit issues with regard to supply-demand imbalance and alloimmune responses and infections, and they also face a future shortage of donors in aging societies. While the production of erythrocytes from iPS cells has challenges to overcome, such as their differentiation into an adult-type phenotype and scalable production, platelet products are qualitatively and quantitatively approaching a clinically applicable level owing to advances in expandable megakaryocyte (MK) lines, platelet-producing bioreactors, and novel reagents. Currently, the establishment of guidelines that assure the quality of iPSC-derived blood products for clinical application is in progress. Considering the minimal risk of tumorigenicity and the expected significant demand of such products, the ex vivo production of iPSC-derived blood cells can be expected to lead iPSC-based regenerative medicine to become common clinical practice.


Assuntos
Células-Tronco Pluripotentes Induzidas , Guias de Prática Clínica como Assunto , Plaquetas/efeitos dos fármacos , Desenho de Drogas , Humanos , Inibidores da Agregação de Plaquetas/uso terapêutico , Trombopoese
8.
Stem Cells Transl Med ; 6(3): 720-730, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28297575

RESUMO

Donor-independent platelet concentrates for transfusion can be produced in vitro from induced pluripotent stem cells (iPSCs). However, culture at 37°C induces ectodomain shedding on platelets of glycoprotein Ibα (GPIbα), the von Willebrand factor receptor critical for adhesive function and platelet lifetime in vivo, through temperature-dependent activation of a disintegrin and metalloproteinase 17 (ADAM17). The shedding can be suppressed by using inhibitors of panmetalloproteinases and possibly of the upstream regulator p38 mitogen-activated protein kinase (p38 MAPK), but residues of these inhibitors in the final platelet products may be accompanied by harmful risks that prevent clinical application. Here, we optimized the culture conditions for generating human iPSC-derived GPIbα+ platelets, focusing on culture temperature and additives, by comparing a new and safe selective ADAM17 inhibitor, KP-457, with previous inhibitors. Because cultivation at 24°C (at which conventional platelet concentrates are stored) markedly diminished the yield of platelets with high expression of platelet receptors, 37°C was requisite for normal platelet production from iPSCs. KP-457 blocked GPIbα shedding from iPSC platelets at a lower half-maximal inhibitory concentration than panmetalloproteinase inhibitor GM-6001, whereas p38 MAPK inhibitors did not. iPSC platelets generated in the presence of KP-457 exhibited improved GPIbα-dependent aggregation not inferior to human fresh platelets. A thrombus formation model using immunodeficient mice after platelet transfusion revealed that iPSC platelets generated with KP-457 exerted better hemostatic function in vivo. Our findings suggest that KP-457, unlike GM-6001 or p38 MAPK inhibitors, effectively enhances the production of functional human iPSC-derived platelets at 37°C, which is an important step toward their clinical application. Stem Cells Translational Medicine 2017;6:720-730.

9.
Blood Adv ; 1(7): 468-476, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29296963

RESUMO

Signaling by thrombopoietin (TPO) in complex with its receptor, c-MPL, is critical for hematopoietic stem cell (HSC) homeostasis and platelet generation. Here we show that TA-316, a novel chemically synthesized c-MPL agonist (CMA), is useful for ex vivo platelet generation from human-induced pluripotent stem (iPS) cell-derived immortalized megakaryocyte progenitor cell lines (imMKCLs). Moreover, the generation is clinically applicable, because self-renewal expansion and platelet release is tightly controllable. TA-316 but not eltrombopag, another CMA, promoted both the self-renewal and maturation of imMKCLs, leading to more than a twofold higher platelet production than that achieved with recombinant human TPO (rhTPO). Interestingly, TA-316 seemed to favor MK-biased differentiation from bone marrow CD34+ HSC/progenitors and imMKCLs through the upregulation of vascular endothelial growth factor A and fibroblast growth factor 2. This result suggests TA-316 could facilitate the development of an efficient and useful system to expand platelets from imMKCLs.

10.
Proc Natl Acad Sci U S A ; 111(45): 16059-64, 2014 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-25355909

RESUMO

Inflammasomes are multiprotein platforms that activate caspase-1, which leads to the processing and secretion of the proinflammatory cytokines IL-1ß and IL-18. Previous studies demonstrated that bacterial RNAs activate the nucleotide-binding domain, leucine-rich-repeat-containing family, pyrin domain-containing 3 (NLRP3) inflammasome in both human and murine macrophages. Interestingly, only mRNA, but neither tRNA nor rRNAs, derived from bacteria could activate the murine Nlrp3 inflammasome. Here, we report that all three types of bacterially derived RNA (mRNA, tRNA, and rRNAs) were capable of activating the NLRP3 inflammasome in human macrophages. Bacterial RNA's 5'-end triphosphate moieties, secondary structure, and double-stranded structure were dispensable; small fragments of bacterial RNA were sufficient to activate the inflammasome. In addition, we also found that 20-guanosine ssRNA can activate the NLRP3 inflammasome in human macrophages but not in murine macrophages. Therefore, human and murine macrophages may have evolved to recognize bacterial cytosolic RNA differently during bacterial infections.


Assuntos
Proteínas de Transporte/imunologia , Inflamassomos/imunologia , Macrófagos/imunologia , RNA Bacteriano/imunologia , RNA Mensageiro/imunologia , Animais , Linhagem Celular Tumoral , Humanos , Interleucina-18/imunologia , Interleucina-1beta/imunologia , Macrófagos/citologia , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Especificidade da Espécie
11.
J Immunol ; 193(2): 627-34, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24928999

RESUMO

Accumulating evidence suggests elements within tumors induce exhaustion of effector T cells and infiltration of immunosuppressive regulatory T cells (Tregs), thus preventing the development of durable antitumor immunity. Therefore, the discovery of agents that simultaneously block Treg suppressive function and reinvigorate effector function of lymphocytes is key to the development of effective cancer immunotherapy. Previous studies have shown that TLR ligands (TLRLs) could modulate the function of these T cell targets; however, those studies relied on cell-free or accessory cell-based assay systems that do not accurately reflect in vivo responses. In contrast, we used a human PBMC-based proliferation assay system to simultaneously monitor the effect of TLRLs on T cells (CD4(+), CD8(+), Tregs), B cells, and NK cells, which gave different and even conflicting results. We found that the TLR7/8L:CL097 could simultaneously activate CD8(+) T cells, B cells, and NK cells plus block Treg suppression of T cells and B cells. The TLRLs TLR1/2L:Pam3CSK4, TLR5L:flagellin, TLR4L:LPS, and TLR8/7L:CL075 also blocked Treg suppression of CD4(+) or CD8(+) T cell proliferation, but not B cell proliferation. Besides CL097, TLR2L:PGN, CL075, and TLR9L:CpG-A, CpG-B, and CpG-C) were strong activators of NK cells. Importantly, we found that Pam3CSK4 could: 1) activate CD4(+) T cell proliferation, 2) inhibit the expansion of IL-10(+) naturally occurring FOXP3(+) Tregs and induction of IL-10(+) CD4(+) Tregs (IL-10-producing type 1 Treg), and 3) block naturally occurring FOXP3(+) Tregs suppressive function. Our results suggest these agents could serve as adjuvants to enhance the efficacy of current immunotherapeutic strategies in cancer patients.


Assuntos
Leucócitos Mononucleares/imunologia , Ativação Linfocitária/imunologia , Linfócitos T Reguladores/imunologia , Receptores Toll-Like/imunologia , Adulto , Análise de Variância , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Flagelina/farmacologia , Fatores de Transcrição Forkhead/imunologia , Fatores de Transcrição Forkhead/metabolismo , Humanos , Imidazóis/farmacologia , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-10/imunologia , Interleucina-10/metabolismo , Interleucina-6/imunologia , Interleucina-6/metabolismo , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lipopeptídeos/farmacologia , Lipopolissacarídeos/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Quinolinas/farmacologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/metabolismo , Tiazóis/farmacologia , Receptores Toll-Like/agonistas , Receptores Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
12.
Proc Natl Acad Sci U S A ; 111(21): 7747-52, 2014 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-24821782

RESUMO

The recognition of cytoplasmic nucleic acid is critical for innate immune responses against microbial infection and is responsible for autoimmunity induced by dead cells. Here, we report the identification of a unique cytosolic nucleic acid cosensor in human airway epithelial cells and fibroblasts: DEAH (Asp-Glu-Ala-His) box polypeptide 29 (DHX29), a member of the DExD/H (Asp-Glu-x-Asp/His)-box helicase family. Knocking down DHX29 by siRNA attenuated the ability of cells to mount type I IFN and IL-6 in response to cytosolic nucleic acids and various viruses by blocking the activation of interferon regulatory factor 3 and NF-κB-p65. The cytosolic nucleic acid sensing by DHX29 in human epithelial cells and fibroblasts is independent of stimulator of interferon genes but is dependent on retinoic acid-inducible gene 1 (RIG-I) and mitochondrial antiviral signaling protein (MAVS). DHX29 binds directly to nucleic acids and interacts with RIG-I and MAVS through its helicase 1 domain, activating the RIG-I-MAVS-dependent cytosolic nucleic acid response. These results suggest that DHX29 is a cytosolic nucleic acid cosensor that triggers RIG-I/MAVS-dependent signaling pathways. This study will have important implications in drug and vaccine design for control of viral infections and viral-induced pathology in the airway.


Assuntos
Citosol/metabolismo , RNA Helicases DEAD-box/metabolismo , Imunidade Inata/imunologia , Ácidos Nucleicos/metabolismo , RNA Helicases/metabolismo , Mucosa Respiratória/metabolismo , Viroses/imunologia , Proteína DEAD-box 58 , DNA Complementar , Humanos , Ácidos Nucleicos/genética , Plasmídeos/genética , Interferência de RNA , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Vírus/genética
13.
Immunity ; 39(1): 123-35, 2013 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-23871209

RESUMO

The NLRP3 inflammasome plays a major role in innate immune responses by activating caspase-1, resulting in secretion of interleukin-18 (IL-18) and IL-1ß. Although cytosolic double-stranded RNA (dsRNA) and bacterial RNA are known to activate the NLRP3 inflammasome, the upstream sensor is unknown. We investigated the potential function of DExD/H-box RNA helicase family members (previously shown to sense cytosolic DNA and RNA to induce type 1 interferon responses) in RNA-induced NLRP3 inflammasome activation. Among the helicase family members tested, we found that targeting of DHX33 expression by short hairpin RNA efficiently blocked the activation of caspase-1 and secretion of IL-18 and IL-1ß in human macrophages that were activated by cytosolic poly I:C, reoviral RNA, or bacterial RNA. DHX33 bound dsRNA via the helicase C domain. DHX33 interacted with NLRP3 and formed the inflammasome complex following stimulation with RNA. We therefore identified DHX33 as a cytosolic RNA sensor that activates the NLRP3 inflammasome.


Assuntos
Proteínas de Transporte/imunologia , RNA Helicases DEAD-box/imunologia , Inflamassomos/imunologia , Macrófagos/imunologia , RNA/imunologia , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Caspase 1/imunologia , Caspase 1/metabolismo , Linhagem Celular , Citosol/imunologia , Citosol/metabolismo , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Expressão Gênica/imunologia , Células HEK293 , Humanos , Immunoblotting , Inflamassomos/genética , Inflamassomos/metabolismo , Interleucina-18/imunologia , Interleucina-18/metabolismo , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Ativação de Macrófagos/imunologia , Macrófagos/metabolismo , Microscopia Confocal , Proteína 3 que Contém Domínio de Pirina da Família NLR , Poli I-C/imunologia , Ligação Proteica/imunologia , RNA/genética , RNA/metabolismo , Interferência de RNA , RNA Bacteriano/imunologia , RNA de Cadeia Dupla/genética , RNA de Cadeia Dupla/imunologia , RNA de Cadeia Dupla/metabolismo , RNA Viral/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
PLoS One ; 7(12): e52341, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23251709

RESUMO

MicroRNAs (miRNAs) have emerged as critical regulators of many cellular responses, through the action of miRNA-induced silencing complex (miRISC)- or miRNA ribonucleoprotein complex (miRNP)-mediated gene repression. Here we studied the role of miRNAs in the development of dendritic cells (DCs), an important immune cell type that is divided into conventional DC (cDC) and plasmacytoid DC (pDC) subsets. We found that miR-22 was highly expressed in mouse CD11c(+) CD11b(+) B220(-) cDCs compared to pDCs, and was induced in DC progenitor cell cultures with GM-CSF, which stimulate CD11c(+) CD11b(+) B220(-) cDC differentiation. Enforced overexpression of miR-22 during DC development enhanced CD11c(+) CD11b(+) B220(-) cDC generation at the expense of pDCs, while miR-22 knockdown demonstrated opposite effects. Moreover, overexpression and knockdown of miR-22 showed significant effects on the mRNA abundance of Irf8, which encodes the transcription factor IRF8 that plays essential roles in DC development. Luciferase reporter assays confirmed that miR-22 binds directly to the 3'UTR of the mouse Irf8 mRNA. Collectively, these results suggest that miR-22 targets Irf8 mRNA for posttranscriptional repression and controls DC subset differentiation.


Assuntos
Células Dendríticas/fisiologia , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética , Regiões 3' não Traduzidas , Animais , Antígeno CD11b/genética , Antígeno CD11b/metabolismo , Antígeno CD11c/genética , Antígeno CD11c/metabolismo , Diferenciação Celular/genética , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo
15.
J Exp Med ; 204(12): 2803-12, 2007 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-18025126

RESUMO

This report shows that interleukin (IL) 17-producing T helper type 17 (Th17) cells predominantly express CC chemokine receptor (CCR) 6 in an animal model of rheumatoid arthritis (RA). Th17 cells induced in vivo in normal mice via homeostatic proliferation similarly express CCR6, whereas those inducible in vitro by transforming growth factor beta and IL-6 additionally need IL-1 and neutralization of interferon (IFN) gamma and IL-4 for CCR6 expression. Forced expression of RORgamma t, a key transcription factor for Th17 cell differentiation, induces not only IL-17 but also CCR6 in naive T cells. Furthermore, Th17 cells produce CCL20, the known ligand for CCR6. Synoviocytes from arthritic joints of mice and humans also produce a large amount of CCL20, with a significant correlation (P = 0.014) between the amounts of IL-17 and CCL20 in RA joints. The CCL20 production by synoviocytes is augmented in vitro by IL-1beta, IL-17, or tumor necrosis factor alpha, and is suppressed by IFN-gamma or IL-4. Administration of blocking anti-CCR6 monoclonal antibody substantially inhibits mouse arthritis. Thus, the joint cytokine milieu formed by T cells and synovial cells controls the production of CCL20 and, consequently, the recruitment of CCR6+ arthritogenic Th17 cells to the inflamed joints. These results indicate that CCR6 expression contributes to Th17 cell function in autoimmune disease, especially in autoimmune arthritis such as RA.


Assuntos
Artrite Experimental/imunologia , Artrite Reumatoide/imunologia , Quimiocina CCL20/genética , Proteínas Inflamatórias de Macrófagos/genética , Receptores CCR6/genética , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Análise de Sequência com Séries de Oligonucleotídeos , Receptores CCR6/antagonistas & inibidores , Linfócitos T/imunologia , Transcrição Genética
16.
Int Immunol ; 18(12): 1789-99, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17068106

RESUMO

Dendritic cells (DCs) and mast cells (MCs) co-localize in peripheral tissues of antigen entry, i.e. skin and mucosa. Due to the proximity of these two cell types, activation of MCs may affect DC functions. Here, we co-cultured human monocyte-derived DCs with cord blood-derived MCs activated by cross-linking of FcepsilonRI to elucidate the net effect of the whole MC products on DCs. Activated MCs induced maturation of DCs, and potently suppressed IL-12p70 production by the DCs. Whereas co-culture of DCs with activated MCs alone did not significantly influence the type of CD4(+) T cell responses induced by the DCs, DCs co-cultured with activated MCs in the presence of pro-inflammatory or T(h)1-inducing factors caused T(h)2 polarization. Although histamine was involved in the induction of DC maturation and T(h)2 polarization by activated MCs, a combinatorial effect of various MC-derived factors, including those acting in a cell contact-dependent manner, was required for the optimal induction of T(h)2-promoting DCs. Furthermore, we demonstrated that clusters of DCs are located closely with MCs in lesions of atopic dermatitis. Collectively, this study suggests that the interaction between DCs and IgE-activated MCs in a pro-inflammatory or even T(h)1-prone environment is instrumental in maintaining and augmenting T(h)2 responses in allergy, and that disruption of the DC-MC interaction may constitute an effective strategy to treat ongoing allergic diseases.


Assuntos
Células Dendríticas/imunologia , Imunoglobulina E/imunologia , Inflamação/imunologia , Mastócitos/imunologia , Células Th2/imunologia , Diferenciação Celular , Células Cultivadas , Células Dendríticas/citologia , Dermatite Atópica/imunologia , Feminino , Sangue Fetal , Humanos , Interleucina-12/imunologia , Células Th2/citologia
17.
Int Immunol ; 18(8): 1197-209, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16772372

RESUMO

Naturally occurring CD25(+)CD4(+) regulatory T cells (Tregs) actively engage in the maintenance of immunologic self-tolerance and immunoregulation. They specifically express the transcription factor Forkhead box P3 (Foxp3) as a master control molecule for their development and function. Although several cell-surface molecules have been reported as Treg-specific markers, such as CD25, glucocorticoid-induced TNFR family-related gene/protein and CTL-associated molecule-4, they are also expressed on activated T cells derived from CD25(-)CD4(+) naive T cells. To identify Treg-specific molecules controlled by Foxp3, we performed DNA microarray analysis by comparing the following pairs of cell populations: fresh CD25(+)CD4(+) T cells versus fresh CD25(-)CD4(+) T cells, activated CD25(+)CD4(+) T cells versus activated CD25(-)CD4(+) T cells and retrovirally Foxp3-transduced CD25(-)CD4(+) T cells versus mock-transduced CD25(-)CD4(+) T cells. We found that the Gpr83, Ecm1, Cmtm7, Nkg7, Socs2 and glutaredoxin genes are predominantly transcribed in fresh and activated natural Treg as well as in Foxp3-transduced cells, while insulin-like 7, galectin-1, granzyme B and helios genes are natural Treg specific but Foxp3 independent. G protein-coupled receptor 83 (Gpr83) expression on the cell surface of natural Treg was confirmed by staining with Gpr83-specific antibody. Retroviral transduction of either group of genes in CD25(-)CD4(+) T cells failed to confer in vitro suppressive activity. Thus, there are several genes that are expressed in a highly Treg-specific fashion. Some of these genes are controlled by Foxp3, and others are not. These genes, in particular, Gpr83, Ecm1 and Helios, could potentially be used as specific markers for natural Treg.


Assuntos
Antígenos CD4/imunologia , Fatores de Transcrição Forkhead/genética , Receptores de Interleucina-2/imunologia , Linfócitos T Reguladores/fisiologia , Animais , Feminino , Fatores de Transcrição Forkhead/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Linfócitos T Reguladores/imunologia , Transcrição Genética , Transdução Genética
18.
Int J Clin Oncol ; 10(5): 357-61, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16247665

RESUMO

A 70-year-old woman was diagnosed with B-cell-type chronic lymphocytic leukemia (B-CLL) in May 2001. Initial white blood cell (WBC) count was 37 x 10(9)/l and most of the cells were mature small lymphocytes. Surface antigen analysis of these lymphocytes revealed positive reactions for CD19, 20, 25, 5, and lambda-light chain. Despite her Rai stage-0 status, various treatments were ineffective, including cyclophosphamide; fludarabine; 6-mercaptopurine; a combination of vincristine, cyclophosphamide, prednisolone, and adriamycin; and etoposide. Her WBC count increased, ranging from 150 to 450 x 10(9)/l, with marked splenomegaly, and symptoms of meningitis, such as headache, ophthalmalgia, hearing disturbance, and abnormal behavior, being manifested. The WBC count in the cerebrospinal fluid was elevated to 134/microl. The surface phenotype of these cells was identical to that of circulating lymphocytes, indicating meningeal involvement of leukemia, a rare complication in B-CLL. At the time of this WBC elevation, 24% of circulating lymphocytes had prominent nucleoli, indicating progression of the disease to CLL/prolymphocytic leukemia. Her symptoms disappeared after repeated intrathecal injections of methotrexate and dexamethazone. After four courses of treatment of the refractory B-CLL with rituximab, an anti-CD20 monoclonal antibody, the WBC count returned to normal levels and the splenomegaly disappeared. She is currently well, with sustained remission, as of April 2004.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Leucemia Linfocítica Crônica de Células B/terapia , Neoplasias Meníngeas/terapia , Idoso , Anticorpos Monoclonais Murinos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Rituximab
19.
Int J Hematol ; 80(2): 183-5, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15481449

RESUMO

Transformation of primary myelofibrosis (PMF) to basophilic leukemia is very rare. We report the case of a 44-year-old man who had had PMF for 6 years. His hematopoiesis deteriorated with marked splenomegaly, requiring multiple red blood cell and platelet transfusions. Soon after splenectomy, progressive basophilia (32.3 x 10(9)/L) developed, infiltrating the skin as well as the bone marrow. The patient underwent allogeneic bone marrow transplantation with cells from an HLA-matched sibling. Despite the presence of hyperhistaminemia (99.1 ng/mL) after conditioning with cyclophosphamide, the pregrafting and post-grafting periods were uneventful. Prophylactic administration of both H1 and H2 receptor antagonists and sufficient hydration appeared to be important.


Assuntos
Transplante de Medula Óssea/métodos , Leucemia Basofílica Aguda/cirurgia , Mielofibrose Primária/complicações , Adulto , Biópsia , Medula Óssea/patologia , Transplante de Medula Óssea/patologia , Hematopoese , Humanos , Leucemia Basofílica Aguda/etiologia , Leucemia Basofílica Aguda/patologia , Masculino , Mielofibrose Primária/patologia
20.
Int J Hematol ; 79(2): 174-7, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15005347

RESUMO

Heavy chain diseases (HCD) are monoclonal lymphoproliferative disorders of B-cells characterized by the synthesis of truncated heavy chains without associated light chains. In patients with mu-HCD, which is a very rare form of HCD, neoplastic cells produce immunoglobulin M heavy chain. The prognosis for patients with mu-HCD is poor, and there is no specific treatment for mu-HCD. In this report, we present a patient with mu-HCD accompanied by splenomegaly and thrombocytopenia. We treated this patient with the fludarabine monophosphate therapy we use for patients with B-cell chronic lymphocytic leukemia. After 5 courses of fludarabine monophosphate treatment, the splenomegaly and thrombocytopenia improved. Fludarabine monophosphate therapy may be a new strategy to improve the prognosis of patients with mu-HCD.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Doença das Cadeias Pesadas/tratamento farmacológico , Fosfato de Vidarabina/análogos & derivados , Fosfato de Vidarabina/administração & dosagem , Feminino , Doença das Cadeias Pesadas/complicações , Doença das Cadeias Pesadas/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Radiografia , Esplenomegalia/diagnóstico por imagem , Esplenomegalia/etiologia , Trombocitopenia/etiologia
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