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1.
J Cell Physiol ; 236(9): 6726-6741, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33611789

RESUMO

Thrombocytopenia is a common complication of human cytomegalovirus (HCMV) infection in immunocompromised hosts, which contributes to poor prognosis even in patients receiving antiviral treatment. Here, we investigated the megakaryo/thrombopoiesis process, including the involvement of the c-Mpl/IEX-1 pathway, after HCMV infection, identified receptors mediating the interaction between megakaryocytes (MKs) and HCMV, and explored novel therapeutic targets. Our data shows that HCMV directly infects megakaryocytes in patients with HCMV DNAemia and influences megakaryopoiesis via the c-Mpl/IEX-1 pathway throughout megakaryocyte maturation, apoptosis, and platelet generation in vivo and in vitro. After treatment with inhibitors of PDGFRα and αvß3, the HCMV infection rate in MKs was significantly reduced, suggesting that IMC-3G3 and anti-αvß3 are potential therapeutic alternatives for viral infection. In summary, our study proposes a possible mechanism and potential treatments for thrombocytopenia caused by HCMV infection and other viral diseases associated with abnormal hemostasis.


Assuntos
Citomegalovirus/fisiologia , Transplante de Células-Tronco Hematopoéticas , Integrina alfaVbeta3/metabolismo , Megacariócitos/virologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores de Trombopoetina/metabolismo , Transdução de Sinais , Trombopoese , Adolescente , Adulto , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Criança , Citomegalovirus/ultraestrutura , Infecções por Citomegalovirus/patologia , Regulação para Baixo , Feminino , Humanos , Masculino , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Análise Multivariada , Ploidias , Fatores de Risco , Receptor 2 Toll-Like/metabolismo , Transplante Homólogo , Adulto Jovem
2.
Blood Adv ; 3(9): 1416-1428, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31053569

RESUMO

Impaired megakaryocyte (MK) maturation and reduced platelet production are important causes of immune thrombocytopenia (ITP). However, MK distribution and bone marrow (BM) niche alteration in ITP are unclear. To investigate the maturation and distribution of MKs in the BM niche and examine the components of BM niche regulation of MK migration, BM and peripheral blood were obtained from 30 ITP patients and 28 healthy donors. Nestin+ mesenchymal stem cells (MSCs) and CD41+ MKs were sorted by fluorescence-activated cell sorting. The components of the BM niche and related signaling were analyzed via immunofluorescence, flow cytometry, enzyme-linked immunosorbent assay, reverse transcription polymerase chain reaction, and western blot analysis. The number of MKs in the BM vascular niche was reduced in ITP. Moreover, the concentrations of CXCL12 and CXCR4+ MKs in the BM were decreased in ITP. Further investigation demonstrated that nestin+ MSCs and CXCL12 messenger RNA (mRNA) in nestin+ MSCs were both reduced whereas the apoptosis of nestin+ MSCs was significantly increased in ITP. Sympathetic nerves, Schwann cells, the proportion of ß3-adrenoreceptor (ß3-AR)+ nestin+ MSCs, and ß3-AR mRNA in nestin+ MSCs were all markedly reduced in ITP. Moreover, matrix metalloproteinase 9, vascular endothelial growth factor (VEGF), and VEGF receptor 1 were significantly reduced in ITP. Our data show that impaired MK distribution mediated by an abnormal CXCL12/CXCR4 axis is partially involved in reduced platelet production in ITP. Moreover, sympathetic neuropathy and nestin+ MSC apoptosis may have an effect on the alterations of BM CXCL12 in ITP.


Assuntos
Megacariócitos/citologia , Células-Tronco Mesenquimais/metabolismo , Nestina/metabolismo , Púrpura Trombocitopênica Idiopática/patologia , Adulto , Medula Óssea/metabolismo , Medula Óssea/patologia , Estudos de Casos e Controles , Quimiocina CXCL12/metabolismo , Feminino , Humanos , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Megacariócitos/metabolismo , Células-Tronco Mesenquimais/citologia , Pessoa de Meia-Idade , Receptores Adrenérgicos beta 3/genética , Receptores Adrenérgicos beta 3/metabolismo , Receptores CXCR4/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
3.
Br J Haematol ; 180(3): 395-411, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29327472

RESUMO

Immune thrombocytopenia (ITP) is an autoimmune disease. Mesenchymal stem cells (MSCs) play important roles in the physiology and homeostasis of the haematopoietic system, including supporting megakaryocytic differentiation from CD34+ haematopoietic progenitor cells. Tumour necrosis factor alpha-induced protein 3 (TNFAIP3, also termed A20) plays a key role in terminating NF-κB signalling. Human genetic studies showed that the polymorphisms of the TNFAIP3 gene may contribute to ITP susceptibility. In this study, we showed a significant decrease in TNFAIP3 and increase in NF-κB/SMAD7 in ITP-MSCs. In co-cultures with CD34+ cells, NF-κB was overexpressed in MSCs from healthy controls (HC-MSCs) after transfection with NFKBIA (IκB)-specific short hairpin (sh)RNAs, resulting in MSC deficiency and a reduction in megakaryocytic differentiation and thrombopoiesis. Knockdown of TNFAIP3 expression using TNFAIP3-specific shRNAs in HC-MSCs affected megakaryocytopoiesis. However, IKBKB knockdown corrected megakaryocytopoiesis inhibition in the ITP-MSCs by decreasing NF-κB expression. Amplified TNFAIP3 expression in ITP-MSCs by TNFAIP3 cDNA can facilitate megakaryocyte differentiation. shRNA-mediated knockdown of SMAD7 expression rescued the impaired MSC function in ITP patients. Therefore, we demonstrate that a pathological reduction in TNFAIP3 levels induced NF-κB/SMAD7 pathway activation, causing a deficiency in MSCs in ITP patients. The ability of ITP-MSCs to support megakaryocytic differentiation and thrombopoiesis of CD34+ cells was impaired.


Assuntos
Células-Tronco Mesenquimais/metabolismo , NF-kappa B/metabolismo , Púrpura Trombocitopênica Idiopática/etiologia , Púrpura Trombocitopênica Idiopática/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Trombopoese , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Biomarcadores , Medula Óssea/patologia , Estudos de Casos e Controles , Diferenciação Celular , Ensaio de Unidades Formadoras de Colônias , Citocinas/biossíntese , Expressão Gênica , Humanos , Imunofenotipagem , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/patologia , Modelos Biológicos , NF-kappa B/genética , Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/genética , Trombopoese/efeitos dos fármacos , Trombopoese/genética , Fator de Crescimento Transformador beta/metabolismo , Tretinoína/farmacologia , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética
4.
Lancet Haematol ; 4(10): e487-e496, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28917657

RESUMO

BACKGROUND: Primary immune thrombocytopenia is a severe bleeding disorder. About 50-85% of patients achieve initial remission from first-line therapies, but optimal second-line treatment remains a challenge. All-trans retinoic acid (ATRA) has an immunomodulatory effect on haemopoiesis, making it a possible treatment option. We aimed to evaluate the efficacy and safety of ATRA plus danazol versus danazol in non-splenectomised patients with corticosteroid-resistant or relapsed primary immune thrombocytopenia. METHODS: We did a multicentre, randomised, open-label, phase 2 study of adult patients (≥18 years) with primary immune thrombocytopenia from five different tertiary medical centres in China. Those eligible were non-splenectomised, resistant to corticosteroid treatment or relapsed, and had a platelet count less than 30 × 109 per L. Masked statisticians used simple randomisation to assign patients (1:1) to receive oral ATRA (10 mg twice daily) plus oral danazol (200 mg twice daily) or oral danazol monotherapy (200 mg twice daily) for 16 weeks. Neither clinicians nor patients were masked to group assignments. All patients were assessed every week during the first 8 weeks of treatment, and at 2-week intervals thereafter. The primary endpoint was 12-month sustained response defined as platelet count of 30 × 109 per L or more and at least a doubling of baseline platelet count (partial response), or a platelet count of 100 × 109 per L or more (complete response) and the absence of bleeding without rescue medication at the 12-month follow-up. All randomly allocated patients, except for those who withdrew consent, were included in the modified intention-to-treat population and efficacy assessment, and all patients who received at least one dose of the study agents were included in the safety analysis. Study enrolment was stopped early because the trial results crossed the interim analysis efficacy boundary for sustained response. This trial is registered with ClinicalTrials.gov, number NCT01667263. FINDINGS: From June 1, 2012, to July 1, 2016, we screened 130 patients for eligibility; 34 were excluded and 96 were randomly assigned. 93 patients were included in the modified intention-to-treat analysis: 45 in the ATRA plus danazol group and 48 in the danazol group. At the 12-month follow-up, sustained response was achieved more frequently in patients receiving ATRA plus danazol than in those receiving danazol monotherapy (28 [62%] of 45 vs 12 [25%] of 48; odds ratio 4·94, 95% CI 2·03-12·02, p=0·00037). Only two grade 3 adverse events were reported: one (2%) patient receiving ATRA plus danazol with dry skin, and one (2%) patient receiving danazol monotherapy with liver injury. There was no grade 4 or worse adverse event or treatment-related death in either group. INTERPRETATION: Patients with primary immune thrombocytopenia given ATRA plus danazol had a rapid and sustained response compared with danazol monotherapy. This finding suggests that ATRA represents a promising candidate for patients with corticosteroid-resistant or relapsed primary immune thrombocytopenia. FUNDING: National Natural Science Foundation of China, Beijing Natural Science Foundation, Beijing Municipal Science and Technology Commission, and the National Key Research and Development Program of China.


Assuntos
Danazol/uso terapêutico , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Tretinoína/uso terapêutico , Adulto , Danazol/administração & dosagem , Danazol/efeitos adversos , Quimioterapia Combinada , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Razão de Chances , Contagem de Plaquetas , Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/mortalidade , Retratamento , Resultado do Tratamento , Tretinoína/administração & dosagem , Tretinoína/efeitos adversos , Adulto Jovem
5.
Stem Cells Dev ; 26(22): 1648-1661, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28946811

RESUMO

Immune thrombocytopenia (ITP) is an autoimmune disease in which dendritic cells (DCs) play a crucial role in the breakdown of self-tolerance. Studies have identified the function of mesenchymal stem cells (MSCs) in promoting the development of regulatory DCs (regDCs). Our previous work revealed that MSCs in ITP exerted senescence, apoptosis, and impaired immunosuppressive effects on T and B cells. However, it is unclear whether the effects of MSCs on regDC induction are altered in ITP. Our data demonstrated that MSCs in ITP were impaired in inhibiting CD1a+ DC and CD14+ DC differentiation from CD34+ hematopoietic progenitor cells (CD34+ HPCs). DCs differentiated with MSCs in ITP exhibited an increased expression of costimulatory molecules CD80/CD86 and secretion of proinflammatory interleukin-12 (IL-12). Accordingly, the tolerogenic characteristics were deficient in DCs induced by MSCs in ITP. DCs differentiated with MSCs in ITP exhibited an impaired ability to inhibit CD3+ T cell proliferation, to suppress T helper (Th)1 cell differentiation, and to induce anergic and regulatory T cells (Tregs). The expression of Notch signaling components was measured in MSCs in ITP. Reduced expression of the ligand Jagged-1, the receptor Notch-1 intracellular domain (NICD-1), and the target gene Hes-1 was identified in MSCs in ITP. The addition of biologically active Jagged-1 to CD34+ HPCs was observed to promote regDC differentiation. When cultured on Jagged-1-coated plates, MSCs in ITP showed an enhancement of the Notch-1 pathway activation, Jagged-1 expression, and the function in inducing regDCs. Pretreatment with all-trans retinoic acid (ATRA) was found to partially restore the capacity of MSCs in both ITP patients and healthy controls in inducing CD34+-derived regDCs. Our data elucidated that MSCs in ITP were impaired in inducing CD34+-regDCs, associated with the Notch-1/Jagged-1 signaling pathway. ATRA could partially correct the impairment of MSCs, suggesting that ATRA could serve as a potential therapeutic alternative for ITP.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Proteína Jagged-1/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Receptores Notch/metabolismo , Tretinoína/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/citologia , Humanos , Células-Tronco Mesenquimais/citologia , Trombocitopenia/metabolismo
6.
Stem Cells Transl Med ; 5(12): 1631-1643, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27471307

RESUMO

: Immune thrombocytopenia (ITP) is characterized by platelet destruction and megakaryocyte dysfunction. Mesenchymal stem cells (MSCs) from ITP patients (MSC-ITP) do not exhibit conventional proliferative abilities and thus exhibit defects in immunoregulation, suggesting that MSC impairment might be a mechanism involved in ITP. Platelet-derived growth factor (PDGF) improves growth and survival in various cell types. Moreover, PDGF promotes MSC proliferation. The aim of the present study was to analyze the effects of PDGF-BB on MSC-ITP. We showed that MSC-ITP expanded more slowly and appeared flattened and larger. MSC-ITP exhibited increased apoptosis and senescence compared with controls. Both the intrinsic and extrinsic pathways account for the enhanced apoptosis. P53 and p21 expression were upregulated in MSC-ITP, but inhibition of p53 with pifithrin-α markedly inhibited apoptosis and senescence. Furthermore, MSCs from ITP patients showed a lower capacity for inhibiting the proliferation of activated T cells inducing regulatory T cells (Tregs) and suppressing the synthesis of anti-glycoprotein (GP)IIb-IIIa antibodies. PDGF-BB treatment significantly decreased the expression of p53 and p21 and increased survivin expression in MSC-ITP. In addition, the apoptotic rate and number of senescent cells in ITP MSCs were reduced. Their impaired ability for inhibiting activated T cells, inducing Tregs, and suppressing the synthesis of anti-GPIIb-IIIa antibodies was restored after PDGF-BB treatment. In conclusion, we have demonstrated that PDGF-BB protects MSCs derived from ITP patients against apoptosis, senescence, and immunomodulatory defects. This protective effect of PDGF-BB is likely mediated via the p53/p21 pathway, thus potentially providing a new therapeutic approach for ITP. SIGNIFICANCE: Immune thrombocytopenia (ITP) is characterized by platelet destruction and megakaryocyte dysfunction. Platelet-derived growth factor (PDGF) improves growth and survival in various cell types and promotes mesenchymal stem cell (MSC) proliferation. PDGF-BB protects MSCs derived from ITP patients against apoptosis, senescence, and immunomodulatory defects. This protective effect of PDGF-BB is likely mediated via the p53/p21 pathway, thus potentially providing a new therapeutic approach for ITP.


Assuntos
Apoptose/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Terapia de Imunossupressão , Células-Tronco Mesenquimais/patologia , Proteínas Proto-Oncogênicas c-sis/farmacologia , Púrpura Trombocitopênica Idiopática/patologia , Anticorpos/farmacologia , Becaplermina , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Biológicos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Receptores de Morte Celular/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
7.
Thromb Res ; 144: 6-11, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27261538

RESUMO

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients are at an increased risk of thrombotic complications, most of which are catheter-related and present a substantial challenge. The incidence of CRT varies considerably depending on clinical factors. However, the underlying pathogenesis and risk factors remain unclear. METHODS: We performed a retrospective nested case-control study in patients following allo-HSCT. Thrombotic episodes were diagnosed based on the clinical suspicion of the physician (pain, swelling, etc.) with subsequent CVC or PICC thrombosis confirmed via duplex ultrasound. Cases with CRT and controls were matched for time of HSCT, age at HSCT, donor source and type of insertion (CVCs or PICC). RESULTS: During the 8-year period, catheters were placed in 2896 patients, with a total of 40 patients (1.38%) developed CRT, among which 11 were associated with CVCs and 29 were associated with PICCs. The median duration from catheter insertion to thrombosis was 97days. Despite reports of an association between thrombosis and infection, central line-associated bloodstream infection was comparable between groups. No significant differences were noted in terms of primary disease, donor type, conditioning regimen or catheter type between the cases and controls. A multivariate regression analysis identified high-dose corticosteroids as independent risk factors for the development of CRT. CRT seems to negatively affect prognosis in allo-HSCT patients. CONCLUSION: In conclusion, we demonstrate that the use of high-dose corticosteroids is correlated with the onset of CRT. However, the efficacy and safety of thromboprophylaxis in this population require further investigation.


Assuntos
Corticosteroides/efeitos adversos , Catéteres/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Trombose/etiologia , Adolescente , Corticosteroides/administração & dosagem , Adulto , Estudos de Casos e Controles , Cateterismo/efeitos adversos , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Trombose/induzido quimicamente , Trombose/diagnóstico , Transplante Homólogo/efeitos adversos , Adulto Jovem
8.
Thromb Res ; 139: 1-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26916289

RESUMO

OBJECTIVES: The aim of this study was to investigate the role of prostacyclin (PGI2) in prolonged isolated thrombocytopenia (PT) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) and the effect of PGI2 on the activation and aggregation of platelets in PT. METHODS: We enrolled 37 patients with PT and 36 controls following allo-HSCT in this study. Platelet aggregation and activation and PGI2 levels were measured. Endothelial progenitor cells (EPCs) from either PT or control patients were cultured ex vivo with serum from either PT or control patients. PGI2 secretions were then measured. PGI2 was added to the platelets ex vivo, and platelet aggregation and activation and PI3K/Akt phosphorylation were analyzed. RESULTS: A higher PGI2 level was observed in the PT patients. The activation and aggregation of platelets were significantly lower in the PT patients. EPCs from PT patients cultured in PT serum secreted higher levels of PGI2, and PGI2 inhibited platelet activation and aggregation in a concentration-dependent manner ex vivo. PI3K/Akt phosphorylation of platelets was regulated by PGI2 after allo-HSCT. Disease status, serum PGI2 level and platelet aggregation were independent risk factors in patients with PT after allo-HSCT. CONCLUSIONS: Higher PGI2 levels and lower platelet activation and aggregation occurred simultaneously in PT patients. PGI2 inhibited platelet activation and aggregation, probably by regulating the phosphorylation of PI3K/Akt.


Assuntos
Epoprostenol/sangue , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Fosfatidilinositol 3-Quinases/metabolismo , Ativação Plaquetária , Proteínas Proto-Oncogênicas c-akt/metabolismo , Trombocitopenia/sangue , Trombocitopenia/etiologia , Adulto , Plaquetas/metabolismo , Plaquetas/patologia , Epoprostenol/metabolismo , Feminino , Humanos , Masculino , Agregação Plaquetária , Transdução de Sinais/efeitos dos fármacos , Trombocitopenia/metabolismo , Trombocitopenia/patologia , Transplante Homólogo , Adulto Jovem
9.
Platelets ; 27(3): 223-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26338255

RESUMO

The role of Helicobacter pylori (H. pylori) infection on thrombocytopenia in chronic hepatitis B (CHB) related compensatory cirrhotic patients is unknown. We conducted an observational study to determine whether H. pylori plays a role in these patients. A total of 255 patients from three centers in China were enrolled in the study. All patients received nucleoside analogs (NA) therapy and were screened for H. pylori infection. Patients were divided into three groups based on their H. pylori infection status and the therapy administered: patients without H. pylori infection who received NA therapy alone (N = 146); patients with H. pylori infection who received NA therapy alone (n = 48); and patients with H. pylori infection who received H. pylori eradication combined with NA therapy (N = 61). We observed that in CHB compensatory cirrhotic patients with H. pylori infection, the platelets count was significantly lower relative to uninfected patients (31 versus 60 × 10(9)/L, p < 0.01). During a 2-year follow-up, the elevation in platelet count was significantly higher in HBV/H. pylori co-infected patients who received the NA and H. pylori eradication treatment compared to the other two groups (p < 0.01). It suggested that H. pylori infection and eradication treatment combined with NA were independent risk factors associated with platelets response during treatment of thrombocytopenia in CHB compensatory cirrhosis (p < 0.01). In conclusion, H. pylori infection may associate with thrombocytopenia in CHB compensatory cirrhosis. H. pylori eradication combined with NA treatment may prove to be beneficial to CHB compensatory cirrhotic patients with thrombocytopenia who are infected with H. pylori.


Assuntos
Infecções por Helicobacter/complicações , Helicobacter pylori , Hepatite B Crônica/complicações , Cirrose Hepática/complicações , Cirrose Hepática/etiologia , Trombocitopenia/diagnóstico , Trombocitopenia/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Feminino , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Fatores de Risco , Índice de Gravidade de Doença , Trombocitopenia/terapia , Resultado do Tratamento , Adulto Jovem
10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 23(6): 1774-9, 2015 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-26708909

RESUMO

Transfusion-associated graft-versus-host disease (TA-GVHD) is a rare complication of blood transfusion. The disease is fulminant and fatal in most patients. TA-GVHD is caused by transfused alloreactive donor T lymphocytes that attack host tissue, including skin, liver, gastrointestinal tract and bone marrow. Most patients are immunocompromised, but immunocompetent patients can also be involved. Irradiation of blood components is generally recommended to prevent the onset of TA-GVHD for susceptible recipients. This review focus on pathogenesis and prevention of TA-GVHD.


Assuntos
Transfusão de Sangue , Doença Enxerto-Hospedeiro , Medula Óssea , Trato Gastrointestinal , Humanos , Fígado , Linfócitos T , Doadores de Tecidos
11.
J Hematol Oncol ; 8: 116, 2015 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-26497387

RESUMO

BACKGROUND: Prolonged isolated thrombocytopenia (PT) is a frequent complication in patients who undergo allogeneic hematopoietic stem cell transplantation (allo-HSCT), and it is associated with an adverse prognosis. In this study, we hypothesized that desialylation on platelet surfaces was associated with PT after allo-HSCT. The mechanisms participating in this process may include NEU1 translocation, platelet apoptosis, and phagocytosis by macrophages. METHODS: PT was defined as a peripheral platelet count less than 100 × 10(9)/L without sustained anemia or leukopenia for more than 3 months after allo-HSCT. 34 patients were identified consecutively from a cohort of 255 patients who underwent allo-HSCT for hematologic malignancies between May and October 2014 at Peking University Institute of Hematology. Desialylation, enzyme expression, and phagocytosis were detected using flow cytometry, immunofluorescence, RT-PCR, Western blot, and so on. RESULTS: Platelets from the PT patients had significantly fewer sialic acids (P = .001) and increased ß-galactose exposure indicative of desialylation on the surface (P = .042), and serum from the PT patients showed a higher sialic acid concentration (8.400 ± 0.2209 µmol/L, P < .001). The sialidase NEU1 was over-expressed from mRNA to protein levels, and its catalytic activity was increased in platelets from the PT patients. Desialylation of GPIbα in the PT patients was correlated with changes in 14-3-3ζ distribution, which, relative to Bad activation, modulated the expression of Bcl-2 family proteins, depolarized the inner membrane of the mitochondria, and initiated the intrinsic mitochondria-dependent pathway of apoptosis. Macrophages derived from the THP-1 cell line preferred to phagocytize desialylated platelets from the PT patients in vitro. We also revealed that oseltamivir (400 µmol/L) could inhibit 50 % of the sialidase activity on platelets and could protect 20 % of platelets from phagocytosis in vitro. CONCLUSIONS: Desialylation of platelets was associated with platelet apoptosis and phagocytosis, whereas oseltamivir could reduce platelet destruction in the periphery, indicating a potential novel treatment for PT after allo-HSCT.


Assuntos
Apoptose , Plaquetas/metabolismo , Transplante de Células-Tronco Hematopoéticas/métodos , Fagocitose , Ácidos Siálicos/sangue , Trombocitopenia/sangue , Adolescente , Adulto , Linhagem Celular Tumoral , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Regulação Enzimológica da Expressão Gênica , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Immunoblotting , Masculino , Microscopia de Fluorescência , Pessoa de Meia-Idade , Neuraminidase/genética , Neuraminidase/metabolismo , Contagem de Plaquetas , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ácidos Siálicos/metabolismo , Trombocitopenia/etiologia , Transplante Homólogo , Adulto Jovem
12.
Leuk Res ; 2015 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-26340916

RESUMO

B-cell acute lymphoblastic leukemia (B-ALL) in adults is a very challenging disease. Relapse following remission after induction chemotherapy remains the major barrier to patient survival. ADAM28 is overexpressed in several human tumors and is related to cell proliferation and lymph node metastasis. To date, no information has been available on the prognostic role of ADAM28 in B-ALL. Fifty consecutive patients with de novo B-ALL and 22 healthy donors were enrolled in this study and were followed for 2.8 years. Our data suggested that ADAM28 expression in B-ALL patients was significantly increased (P<0.0001). Patients experiencing disease relapse exhibited significantly increased ADAM28 expression, compared with those with favorable outcomes (P=0.0094). Notably, ADAM28 overexpression was associated with lower probabilities of relapse-free survival (RFS) and event-free survival (EFS) (P<0.001) and was a significant prognostic factor (P<0.001). In vitro, the PI3K/Akt pathway inhibitor, as well as arsenic trioxide (ATO), down-regulated ADAM28 expression. Our results were the first to indicate that ADAM28 overexpression in B-ALL patients is correlated with relapse. ADAM28 overexpression is potentially regulated by the PI3K/Akt pathway. These data demonstrate that ADAM28 might serve as a novel biomarker for evaluating relapse in B-ALL and as a potential therapeutic target in B-ALL patients.

13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 23(2): 490-4, 2015 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-25948211

RESUMO

OBJECTIVE: This study was to construct the lentivirus vector carrying hepatocyte growth factor (HGF) gene and to explore the condition for transfecting the adipocyte-derived mesenchymal stem cells (ADSC) by HGF lentivirus. METHODS: The target gene was obtained from plasmid carrying HGF gene by PCR and was cloned into GV287 vector. The recombinant GV287-HGF vector plasmid and lentivirus-packing plasmid were co-transfected into 293 T cells to generate HGF lentivirus, and the virus titer was assayed, then the ADSC were transfected by using recombinant HGF lentivirus, and the optimal multplicity of infection (MOI) was detected. RESULTS: The PCR product of HGF gene was consistent with expectant sizes, suggesting that the electrophoretic result of recombinant GV287-HGF plasmid PCR product was correct. The sequencing analysis of cleaved product showed consistance of obtained results with the sequences of target gene, suggesting correct construction of recombinant lentivirus carrying HGF gene. The ELISA showed that the virus tilter was 5×10(8) TU/ml. The optimal MOI for transfecting ADSC with recombinant lentivirus carrying HGF gene was 50. CONCLUSION: The lentivirus vector expressing human HGF gene has been constructed, and transfected the ADSC succesfully. This study lays a foundation for further stadying the ADSC over-expressioning HGF, treating the radiation damage of bone marrow and impartant internal organs.


Assuntos
Células-Tronco Mesenquimais , Adipócitos , Animais , Linhagem Celular , Expressão Gênica , Vetores Genéticos , Fator de Crescimento de Hepatócito , Humanos , Lentivirus , Plasmídeos , Ratos , Transfecção
14.
Thromb Res ; 135(5): 835-40, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25747536

RESUMO

INTRODUCTION: Acquired haemophilia A (AHA) is an autoimmune disease that potentially leads to severe bleeding and has a high rate of mortality. This collaborative study aimed to assess the efficacy of the co-administration of FVIII and low-dose rFVIIa in patients with AHA. MATERIALS AND METHODS: This study retrospectively compared the combined FVIII/low-dose rFVIIa therapy (initial dose range of 25-55µg/Kg) with the combined FVIII/PCC therapy and low-dose rFVIIa monotherapy. Adverse drug reactions and recurrent bleeding episodes were also monitored. Crude comparisons and the exact conditional logistic regression were performed to compare the outcomes between three treatment groups. RESULTS: First bleeding episodes of 56 consecutive patients from 5 centres were analyzed, and 37 bleeding episodes (66.1%) were determined to be severe. Specifically, the rate of bleeding control was significantly higher with the FVIII/low-dose rFVIIa therapy compared to that of the low-dose rFVIIa alone therapy or the FVIII/PCC therapy (58.3% vs. 41.7% vs. 95.0%, respectively). Analyzing of total 236 bleeding episodes showed a clear positive association between the early initiation of haemostatic treatment and efficacy. No therapy-related adverse events in which thrombosis predominated were reported. CONCLUSIONS: The combination of FVIII and low-dose rFVIIa offers an ideal haemostatic cover and may be promoted as a feasible and safe therapy protocol for patients with AHA.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Fator VIII/uso terapêutico , Fator VIIa/uso terapêutico , Hemofilia A/tratamento farmacológico , Hemostasia/efeitos dos fármacos , Doença Aguda , Doenças Autoimunes/sangue , Doenças Autoimunes/etiologia , Fatores de Coagulação Sanguínea/efeitos adversos , Fatores de Coagulação Sanguínea/uso terapêutico , Quimioterapia Combinada , Intervenção Médica Precoce , Fator VIII/efeitos adversos , Fator VIII/farmacologia , Fator VIIa/efeitos adversos , Fator VIIa/farmacologia , Hemofilia A/sangue , Hemofilia A/etiologia , Hemorragia/prevenção & controle , Humanos , Imunossupressores/uso terapêutico , Tempo de Tromboplastina Parcial , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento
15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 22(4): 1142-7, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25130845

RESUMO

A disintegrin-metalloproteinase 28 (ADAM28) is one of important members of ADAM family, that is involved in various biological events including cell adhesion, proteolysis, growth and metastasis of solid tumors and hematological malignancies. Studies have shown that ADAM28 is highly expressed in several human tumors, such as lung, breast and bladder cancers, and chronic lymphocytic leukemia, and its tissue expression levels correlate with cancer metastasis. ADAM28-mediated cancer cell metastasis may be related with the cleavage of von Willebrand's factor (vWF), insulin-like growth factor binding protein-3 (IGFBP-3) and connective tissue growth factor (CTGF), as well as the promoting PSGL-1/P-selectin-mediated cell adhesion. This review summarizes the basic and translational aspects of ADAM28 biology that might stimulate the interest in ADAM28 research and discovery of novel ADAM28 targets, providing potential novel therapies for metastatic cancers.


Assuntos
Proteínas ADAM/metabolismo , Metástase Neoplásica , Neoplasias/patologia , Adesão Celular , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de von Willebrand/metabolismo
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