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1.
J Transl Med ; 18(1): 148, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32238166

RESUMO

BACKGROUND: Adoptive transfer of virus-specific T cells (VSTs) represents a prophylactic and curative approach for opportunistic viral infections and reactivations after transplantation. However, inadequate frequencies of circulating memory VSTs in the T-cell donor's peripheral blood often result in insufficient enrichment efficiency and purity of the final T-cell product, limiting the effectiveness of this approach. METHODS: This pilot study was designed as a cross-over trial and compared the effect of a single bout (30 min) of high-intensity interval training (HIT) with that of 30 min of continuous exercise (CONT) on the frequency and function of circulating donor VSTs. To this end, we used established immunoassays to examine the donors' cellular immune status, in particular, with respect to the frequency and specific characteristics of VSTs restricted against Cytomegalovirus (CMV)-, Epstein-Barr-Virus (EBV)- and Adenovirus (AdV)-derived antigens. T-cell function, phenotype, activation and proliferation were examined at different time points before and after exercise to identify the most suitable time for T-cell donation. The clinical applicability was determined by small-scale T-cell enrichment using interferon- (IFN-) γ cytokine secretion assay and virus-derived overlapping peptide pools. RESULTS: HIT proved to be the most effective exercise program with up to fivefold higher VST response. In general, donors with a moderate fitness level had higher starting and post-exercise frequencies of VSTs than highly fit donors, who showed significantly lower post-exercise increases in VST frequencies. Both exercise programs boosted the number of VSTs against less immunodominant antigens, specifically CMV (IE-1), EBV (EBNA-1) and AdV (Hexon, Penton), compared to VSTs against immunodominant antigens with higher memory T-cell frequencies. CONCLUSION: This study demonstrates that exercise before T-cell donation has a beneficial effect on the donor's cellular immunity with respect to the proportion of circulating functionally active VSTs. We conclude that a single bout of HIT exercise 24 h before T-cell donation can significantly improve manufacturing of clinically applicable VSTs. This simple and economical adjuvant treatment proved to be especially efficient in enhancing virus-specific memory T cells with low precursor frequencies.

2.
Clin Res Cardiol ; 109(5): 539-548, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31401672

RESUMO

AIMS: In the placebo-controlled, double-blind BOne marrOw transfer to enhance ST-elevation infarct regeneration (BOOST) 2 trial, intracoronary autologous bone marrow cell (BMC) transfer did not improve recovery of left ventricular ejection fraction (LVEF) at 6 months in patients with ST-elevation myocardial infarction (STEMI) and moderately reduced LVEF. Regional myocardial perfusion as determined by adenosine stress perfusion cardiac magnetic resonance imaging (S-CMR) may be more sensitive than global LVEF in detecting BMC treatment effects. Here, we sought to evaluate (i) the changes of myocardial perfusion in the infarct area over time (ii) the effects of BMC therapy on infarct perfusion, and (iii) the relation of infarct perfusion to LVEF recovery at 6 months. METHODS AND RESULTS: In 51 patients from BOOST-2 (placebo, n = 10; BMC, n = 41), S-CMR was performed 5.1 ± 2.9 days after PCI (before placebo/BMC treatment) and after 6 months. Infarct perfusion improved from baseline to 6 months in the overall patient cohort as reflected by the semi-quantitative parameters, perfusion defect-infarct size ratio (change from 0.54 ± 0.20 to 0.43 ± 0.22; P = 0.006) and perfusion defect-upslope ratio (0.54 ± 0.23 to 0.68 ± 0.22; P < 0.001), irrespective of randomised treatment. Perfusion defect-upslope ratio at baseline correlated with LVEF recovery (r = 0.62; P < 0.001) after 6 months, with a threshold of 0.54 providing the best sensitivity (79%) and specificity (74%) (area under the curve, 0.79; 95% confidence interval, 0.67-0.92). CONCLUSION: Infarct perfusion improves from baseline to 6 months and predicts LVEF recovery in STEMI patients undergoing early PCI. Intracoronary BMC therapy did not enhance infarct perfusion in the BOOST-2 trial.

3.
Transpl Infect Dis ; 22(1): e13201, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31643129

RESUMO

Adenovirus (HAdV) infections confer a high risk of morbidity and mortality for immunocompromised patients after stem cell transplantation (SCT). Treatment with standard antiviral drugs is of limited efficacy and associated with a high rate of adverse effects. HAdV-specific T cells are crucial for sustained viral elimination and the efficacy of adoptive T-cell therapy with donor-derived HAdV-specific T cells has been reported by several investigators. Here, we report our experience with the transfer of HAdV-specific T cells specific for penton, which was recently identified as an immunodominant target of T cells, and hexon in a 14-year-old boy after T-cell-depleted haploidentical SCT for myelodysplastic syndrome (MDS). He developed severe HAdV-associated enteritis complicated by acute graft-versus-host disease (GvHD). The patient received ten infusions of allogeneic HAdV-specific T cells manufactured from the haploidentical stem cell donor using the CliniMacs Interferon-γ (IFN-γ) cytokine capture and immunomagnetic selection. Initially, T cells were generated against the immunodominant target hexon and in subsequent transfers dual antigen-specific T cells against hexon and penton were applied. T-cell transfers were scheduled individually tailored to current immunosuppressive treatment. Each transfer was followed by reduction of HAdV load in peripheral blood and clinical improvement. Importantly, T-cell responses to both penton and hexon pools emerged in patient blood after repetitive transfers. Unfortunately, the patient experienced bacterial sepsis, and in this context, severe GvHD requiring intensive immunosuppression followed by secondary progression of HAdV infection. The patient succumbed to multiorgan failure 283 days after SCT. This case demonstrates the feasibility of HAdV-specific T-cell transfer even in the presence of immunosuppressive treatment. Targeting of multiple immunodominant viral proteins may prove valuable in patients with complicated HAdV infections.

4.
Front Immunol ; 9: 1475, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29997626

RESUMO

Epstein-Barr virus (EBV)-associated posttransplant lymphoproliferative disease (PTLD) with central nervous system (CNS) involvement is a severe complication after solid organ transplantation. Standard treatment with reduction of immunosuppression and anti-CD20 antibody application often fails leading to poor outcome. Here, we report the case of an 11-year-old boy with multilocular EBV-positive CNS PTLD 10 years after liver transplantation. Complete remission was achieved by repeated intravenous and intrathecal anti-CD20 antibody rituximab administration combined with intrathecal chemotherapy (methotrexate, cytarabine, prednisone) over a time period of 3 months. Due to the poor prognosis of CNS PTLD and lack of EBV-specific T-cells (EBV-CTLs) in patient's blood, we decided to perform EBV-directed T-cell immunotherapy as a consolidating treatment. The patient received five infusions of allogeneic EBV-CTLs from a 5/10 HLA-matched unrelated third-party donor. No relevant acute toxicity was observed. EBV-CTLs became detectable after first injection and increased during the treatment course. Next-generation sequencing (NGS) TCR-profiling verified the persistence and expansion of donor-derived EBV-specific clones. After two transfers, epitope spreading to unrelated EBV antigens occurred suggesting onset of endogenous T-cell production, which was supported by detection of recipient-derived clones in NGS TCR-profiling. Continuous complete remission was confirmed 27 months after initial diagnosis.

5.
Transfus Med Hemother ; 45(3): 148-150, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29928167
6.
Transfus Med Hemother ; 44(4): 208-209, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28924424
7.
Transfus Med Hemother ; 44(3): 188-200, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28626370

RESUMO

BACKGROUND: Currently, there is an extensive but highly inconsistent body of literature regarding donor adverse events (AEs) in haemapheresis. As the reports diverge with respect to types and grading of AEs, apheresis procedures and machines, the range of haemapheresis-related AEs varies widely from about 0.03% to 6.6%. METHODS: The German Society for Transfusion Medicine and Immunohaematology (DGTI) formed a 'Haemapheresis Vigilance Working Party' (Arbeitsgemeinschaft Hämapheresevigilanz; AGHV) to create an on-line registry for comprehensive and comparable AE assessment with all available apheresis devices in all types of preparative haemapheresis: plasmapheresis (PLS), plateletpheresis (PLT), red blood cell apheresis, all kind of leukaphereses (autologous/allogeneic blood stem cell apheresis, granulocyte apheresis, lymphocyte/monocyte apheresis) and all possible types of multi-component apheresis. To ensure the comparability of the data, the AGHV adopted the 'Standard for Surveillance of Complications Related to Blood Donation' from the International Society for Blood Transfusion in cooperation with the International Haemovigilance Network (IHN) and the American Association of Blood Banks for AE acquisition and automated evaluation. The registry is embedded in a prospective observational multi-centre study with a study period of 7 years. RESULTS: A preliminary evaluation encompassed the time period from January, 2012 to December, 2015. During this time, the system proved to be safe and stable. Out of approximately 345,000 haemaphereses 16,477 AEs were reported (4.9%) from 20 participating centres. The majority of AEs occurred in PLSs (63%), followed by PLT (34.5%) and SC (2.2%). Blood access injuries (BAI) accounted for about 55% of the supplied AEs, whereas citrate toxicity symptoms, vasovagal reactions and technical events (e.g. disposable leakages, software failures) rather equally affected haemaphereses at 8-15%. Out of 12,348 finalized AEs, 8,759 (70.1%) were associated with a procedure-related break-off, with BAI being the prevailing cause (5,463/8,759; 62.4%). An automated centre- and procedure-specific AE evaluation according to the latest IHN standard and AGHV pre-settings is available within a few minutes. CONCLUSIONS: An on-line electronic platform for comprehensive assessment and centre-specific automated evaluation of AEs in haemaphereses has been developed and proved to be stable and safe over a period of 4 years.

8.
Eur Heart J ; 38(39): 2936-2943, 2017 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-28431003

RESUMO

Aims: Intracoronary infusion of autologous nucleated bone marrow cells (BMCs) enhanced the recovery of left ventricular ejection fraction (LVEF) after ST-segment elevation myocardial infarction (STEMI) in the randomised-controlled, open-label BOOST trial. We reassessed the therapeutic potential of nucleated BMCs in the randomised placebo-controlled, double-blind BOOST-2 trial conducted in 10 centres in Germany and Norway. Methods and results: Using a multiple arm design, we investigated the dose-response relationship and explored whether γ-irradiation which eliminates the clonogenic potential of stem and progenitor cells has an impact on BMC efficacy. Between 9 March 2006 and 16 July 2013, 153 patients with large STEMI were randomly assigned to receive a single intracoronary infusion of placebo (control group), high-dose (hi)BMCs, low-dose (lo)BMCs, irradiated hiBMCs, or irradiated loBMCs 8.1 ± 2.6 days after percutaneous coronary intervention (PCI) in addition to guideline-recommended medical treatment. Change in LVEF from baseline (before cell infusion) to 6 months as determined by MRI was the primary endpoint. The trial is registered at Current Controlled Trials (ISRCTN17457407). Baseline LVEF was 45.0 ± 8.5% in the overall population. At 6 months, LVEF had increased by 3.3 percentage points in the control group and 4.3 percentage points in the hiBMC group. The estimated treatment effect was 1.0 percentage points (95% confidence interval, -2.6 to 4.7; P = 0.57). The treatment effect of loBMCs was 0.5 percentage points (-3.0 to 4.1; P = 0.76). Likewise, irradiated BMCs did not have significant treatment effects. BMC transfer was safe and not associated with adverse clinical events. Conclusion: The BOOST-2 trial does not support the use of nucleated BMCs in patients with STEMI and moderately reduced LVEF treated according to current standards of early PCI and drug therapy.


Assuntos
Transplante de Medula Óssea/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Células da Medula Óssea/efeitos da radiação , Método Duplo-Cego , Feminino , Raios gama , Humanos , Infusões Intralesionais , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea , Transplante de Células-Tronco/métodos , Células-Tronco/efeitos da radiação , Transplante Autólogo , Resultado do Tratamento , Função Ventricular Esquerda/fisiologia
9.
Transfusion ; 57(1): 60-69, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27888517

RESUMO

BACKGROUND: Inherited and acquired marrow failure syndromes most commonly lead to defect in myeloid and/or neutrophil differentiation and/or function. Besides this, neutropenia induced by cancer-adjusted chemotherapy is a frequent clinical problem. In both cases, cell replacement therapy is a well-established, but due to necessity of donors limited and perilous procedure. Therefore, autologous cell replacement from patients' own marrow-derived cells lowers risk and bares new possibilities for therapy. Since the immune system of the marmoset monkey is known to show high similarity to humans, preclinical studies with these animals bare high hopes for immunologic research and cell replacement therapy. STUDY DESIGN AND METHODS: Marmoset-induced pluripotent stem (iPS) cells (cj-iPSC) were first cultivated on mouse embryonic feeder cells in medium containing recombinant human vascular endothelial growth factor. After 13 days, CD34+/vascular endothelial growth factor receptor-2 (VEGFR2)- cells were sorted, treated with interleukin (IL-3), thrombopoietin, and stem cell factor for 20 days and further cultivated with granulocyte-colony-stimulating factor (G-CSF) and IL-3 for 10 days. RESULTS: CD34+/VEGFR2- cells could be generated in high amounts (39.65 ± 6.01%; 2.31 × 105 cells). Afterward, these hematopoietic progenitors could be successfully differentiated into mature cj-iPSC-derived neutrophils showing similar morphology, specific surface antigens, and neutrophil-specific gene products and in vitro phagocytic activity. CONCLUSION: cj-iPSC-derived neutrophils bare high hopes in hematologic cell replacement therapy. They exhibit high morphologic similarity to native neutrophils and present neutrophil-specific surface antigens, antimicrobial proteins, and gene products yielding an auspicious approach for continuative experiments including tests in living animals.


Assuntos
Diferenciação Celular , Células-Tronco Pluripotentes Induzidas/metabolismo , Neutrófilos/metabolismo , Animais , Antígenos CD34/metabolismo , Callithrix , Embrião de Mamíferos/citologia , Células Alimentadoras/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Camundongos , Neutrófilos/citologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
10.
Front Immunol ; 7: 393, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27746781

RESUMO

BACKGROUND AND AIMS: The infusion of enriched CMV-specific donor T-cells appears to be a suitable alternative for the treatment of drug-resistant CMV reactivation or de novo infection after both solid organ and hematopoietic stem cell transplantation. Antiviral lymphocytes can be selected from apheresis products using the CliniMACS Cytokine-Capture-System® either with the well-established CliniMACS® Plus (Plus) device or with its more versatile successor CliniMACS Prodigy® (Prodigy). METHODS: Manufacturing of CMV-specific T-cells was carried out with the Prodigy and Plus in parallel starting with 0.8-1 × 109 leukocytes collected by lymphapheresis (n = 3) and using the MACS GMP PepTivator® HCMVpp65 for antigenic restimulation. Target and non-target cells were quantified by a newly developed single-platform assessment and gating strategy using positive (CD3/CD4/CD8/CD45/IFN-γ), negative (CD14/CD19/CD56), and dead cell (7-AAD) discriminators. RESULTS: Both devices produced largely similar results for target cell viabilities: 37.2-52.2% (Prodigy) vs. 51.1-62.1% (Plus) CD45+/7-AAD- cells. Absolute numbers of isolated target cells were 0.1-3.8 × 106 viable IFN-γ+ CD3+ T-cells. The corresponding proportions of IFN-γ+ CD3+ T-cells ranged between 19.2 and 95.1% among total CD3+ T-cells and represented recoveries of 41.9-87.6%. Within two parallel processes, predominantly IFN-γ+ CD3+CD8+ cytotoxic T-cells were enriched compared to one process that yielded a higher amount of IFN-γ+ CD3+CD4+ helper T lymphocytes. T-cell purity was higher for the Prodigies products that displayed a lower content of contaminating IFN-γ- T-cells (3.6-20.8%) compared to the Plus products (19.9-80.0%). CONCLUSION: The manufacturing process on the Prodigy saved both process and hands-on time due to its higher process integration and ability for unattended operation. Although the usage of both instruments yielded comparable results, the lower content of residual IFN-γ- T-cells in the target fractions produced with the Prodigy may allow for a higher dosage of CMV-specific donor T-cells without increasing the risk for graft-versus-host disease.

12.
Afr J Lab Med ; 4(1): 297, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-28879098

RESUMO

BACKGROUND: Currently, no data are available on the prevalence of red blood cell (RBC) antibody formation amongst Kenyan patients with multiple transfusion needs, such as patients with sickle cell disease (SCD) or haematological malignancies (HM) and solid (SM) malignancies. OBJECTIVES: We determined the prevalence and specificities of RBC alloantibodies and autoantibodies in two patient groups with recurrent transfusion demands at Kenyatta National Hospital, Nairobi, Kenya. METHOD: Between February and August 2014, 300 samples from SCD, HM and SM patients were collected and screened for alloantibodies. Samples from 51 healthy blood donors were screened for irregular antibodies and phenotyped. RESULTS: Amongst the 228 patients with viable samples (SCD, n = 137; HM, n = 48; SM, n = 43), the median transfusion frequency was two to three events per group, 38 (16.7%) were RBC immunised and 32 (14.0%) had a positive direct antiglobulin test. We identified specific alloantibodies in six patients (2.6%). Four of these six were SCD patients (2.9%) who had specific RBC alloantibodies (anti-Cw, anti-M, anti-Cob, anti-S); amongst HM patients one had anti-K and one had anti-Lea. RBC autoantibody prevalence was 3.1% (7/228). Amongst the healthy blood donors, the Ror, ccD.ee and R2r, ccD.Ee phenotypes accounted for 82% of the Rhesus phenotypes and all were Kell negative. CONCLUSION: The numbers of transfusions and the rates of RBC alloantibodies are low and the most important RBC alloantibody-inducing blood group antigens are relatively homogeneously distributed in this population. A general change in the Kenyatta National Hospital pre-transfusion test regimen is thus not necessary. The current transfusion practice should be reconsidered if transfusion frequencies increase in the future.

13.
J Transl Med ; 12: 336, 2014 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-25510656

RESUMO

BACKGROUND: The adoptive transfer of allogeneic antiviral T lymphocytes derived from seropositive donors can safely and effectively reduce or prevent the clinical manifestation of viral infections or reactivations in immunocompromised recipients after hematopoietic stem cell (HSCT) or solid organ transplantation (SOT). Allogeneic third party T-cell donors offer an alternative option for patients receiving an allogeneic cord blood transplant or a transplant from a virus-seronegative donor and since donor blood is generally not available for solid organ recipients. Therefore we established a registry of potential third-party T-cell donors (allogeneic cell registry, alloCELL) providing detailed data on the assessment of a specific individual memory T-cell repertoire in response to antigens of cytomegalovirus (CMV), Epstein-Barr virus (EBV), adenovirus (ADV), and human herpesvirus (HHV) 6. METHODS: To obtain a manufacturing license according to the German Medicinal Products Act, the enrichment of clinical-grade CMV-specific T cells from three healthy CMV-seropositive donors was performed aseptically under GMP conditions using the CliniMACS cytokine capture system (CCS) after restimulation with an overlapping peptide pool of the immunodominant CMVpp65 antigen. Potential T-cell donors were selected from alloCELL and defined as eligible for clinical-grade antiviral T-cell generation if the peripheral fraction of IFN-γ(+) T cells exceeded 0.03% of CD3(+) lymphocytes as determined by IFN-γ cytokine secretion assay. RESULTS: Starting with low concentration of IFN-γ(+) T cells (0.07-1.11%) we achieved 81.2%, 19.2%, and 63.1% IFN-γ(+)CD3(+) T cells (1.42 × 10(6), 0.05 × 10(6), and 1.15 × 10(6)) after enrichment. Using the CMVpp65 peptide pool for restimulation resulted in the activation of more CMV-specific CD8(+) than CD4(+) memory T cells, both of which were effectively enriched to a total of 81.0% CD8(+)IFN-γ(+) and 38.4% CD4(+)IFN-γ(+) T cells. In addition to T cells and NKT cells, all preparations contained acceptably low percentages of contaminating B cells, granulocytes, monocytes, and NK cells. The enriched T-cell products were stable over 72 h with respect to viability and ratio of T lymphocytes. CONCLUSIONS: The generation of antiviral CD4(+) and CD8(+) T cells by CliniMACS CCS can be extended to a broad spectrum of common pathogen-derived peptide pools in single or multiple applications to facilitate and enhance the efficacy of adoptive T-cell immunotherapy.


Assuntos
Doadores de Sangue , Transplante de Células , Indústria Farmacêutica/normas , Linfócitos T/imunologia , Viroses/terapia , Adenoviridae/imunologia , Citomegalovirus/imunologia , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 6/imunologia , Humanos , Imunoterapia , Controle de Qualidade , Viroses/imunologia , Viroses/virologia
14.
Transfus Med Hemother ; 41(3): 170-1, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25053928
15.
Platelets ; 25(1): 8-15, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23534885

RESUMO

Platelet dysfunction can cause clinically relevant bleeding. Treatment with DDAVP is advocated for this condition. DDAVP increases von Willebrand factor (VWF) on endothelial cells (ECs) and in plasma. VWF could facilitate platelet deposition on subendothelial collagen. VWF also facilitates platelet/EC interactions. Therefore DDAVP could precipitate thromboembolic events. We used a flow chamber model to study in vitro and ex vivo if DDAVP alters recruitment of platelets to EC and collagen. Resting or TRAP-activated platelets and EC were treated individually or simultaneously with 0.4 ng/ml DDAVP. Fluorophor-labeled platelets (10(6)/ml) were resuspended in reconstituted blood and superfused across EC and collagen in an in vitro flow chamber model at arterial shear (320 s(-1)). Adhesion of platelets to the respective surface was recorded fluorescence microscopically and platelet covered area was assessed. TRAP significantly induced adhesiveness of platelets for collagen and EC. DDAVP pretreatment of platelets did not affect adhesiveness of resting or TRAP-activated platelets for collagen or EC. Adhesiveness of resting but not TRAP-activated platelets was induced on DDAVP-treated EC. DDAVP-conditioned EC supernatant contained vWF and significantly increased platelet deposition on collagen. Platelets from patients with clinically suspected platelet dysfunction undergoing aortic valve replacement exhibited decreased platelet deposition on collagen surfaces. In summary, our data confirm that DDAVP can induce release of platelet adhesion promoting factors from EC, which is most likely vWF. DDAVP has no direct effect on platelets. Blood samples from DDAVP-treated patients do not exhibit significantly augmented platelet deposition on collagen ex vivo. This influence of released promoting factors might cause an increase of undesirable interactions of platelets with EC.


Assuntos
Plaquetas/efeitos dos fármacos , Comunicação Celular/efeitos dos fármacos , Colágeno/farmacologia , Desamino Arginina Vasopressina/farmacologia , Células Endoteliais/efeitos dos fármacos , Ativação Plaquetária/efeitos dos fármacos , Plaquetas/citologia , Células Cultivadas , Colágeno/química , Células Endoteliais/citologia , Humanos , Adesividade Plaquetária/efeitos dos fármacos , Fator de von Willebrand/metabolismo
16.
PLoS One ; 8(11): e80454, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24260393

RESUMO

BACKGROUND: Myostatin is a muscle derived factor that functions as a negative regulator of skeletal muscle growth. Induction of myostatin expression was observed in rodent models of muscle wasting and in cachectic patients with cancer or pulmonary disease. Therefore, there is an increasing interest to use serum myostatin as a biomarker. METHODS: We established an immunoradiometric sandwich assay (IRMA), which uses a commercially available chicken polyclonal, affinity purified antibody directed against human myostatin prodomain. We determined the serum concentrations of myostatin prodomain in 249 healthy individuals as well as 169 patients with heart failure, 53 patients with cancer and 44 patients with chronic pulmonary disease. RESULTS: The IRMA had a detection limit of 0.7ng/ml, an intraassay imprecision of ≤14.1% and an interassay imprecision of ≤ 18.9%. The specificity of our assay was demonstrated by size exclusion chromatography, detection of myostatin by Western-blotting and a SMAD-dependent transcriptional-reporter assay in the signal-rich serum fractions, as well as lack of interference by unspecific substances like albumin, hemoglobin or lipids. Myostatin prodomain was stable at room temperature and resistant to freeze-thaw cycles. Apparently healthy individuals over the age of 55 had a median myostatin prodomain serum concentration of 3.9ng/ml (25(th)-75(th) percentiles, 2-7ng/ml) and we could not detect increased levels in patients with stable chronic heart failure or cancer related weight loss. In contrast, we found strongly elevated concentrations of myostatin prodomain (median 26.9ng/ml, 25(th)-75(th) percentiles, 7-100ng/ml) in the serum of underweight patients with chronic pulmonary disease. CONCLUSIONS: We established a highly specific IRMA for the quantification of myostatin prodomain concentration in human serum. Our assay could be useful to study myostatin as a biomarker for example in patients with chronic pulmonary disease, as we detected highly elevated myostatin prodomain serum levels in underweight individuals of this group.


Assuntos
Ensaio Imunorradiométrico/métodos , Miostatina/sangue , Adulto , Idoso , Biomarcadores/sangue , Biomarcadores/metabolismo , Doença Crônica , Feminino , Neoplasias Gastrointestinais/sangue , Neoplasias Gastrointestinais/metabolismo , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/metabolismo , Humanos , Ensaio Imunorradiométrico/normas , Pneumopatias/sangue , Pneumopatias/metabolismo , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Atrofia Muscular/sangue , Atrofia Muscular/etiologia , Atrofia Muscular/metabolismo , Miostatina/metabolismo , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Biol Blood Marrow Transplant ; 19(10): 1480-92, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23891747

RESUMO

Adoptive immunotherapy with virus-specific T lymphocytes can efficiently reconstitute antiviral immunity against cytomegalovirus (CMV), Epstein-Barr virus (EBV), and adenovirus (ADV) without causing acute toxicity or increasing the risk of graft-versus-host disease. To gain insight into antiviral T cell repertoires and to identify the most efficient antigens for immunotherapy, the frequencies of CMV-, EBV- and ADV-specific T cells in 204 HLA-typed healthy donors were assessed using viral peptides and peptide pools. Confirmatory testing for CMV serology by Western blot technique revealed 19 of 143 (13%) false-positive results. We observed highly significant individual and overall differences in T cell frequencies against CMV, EBV, and ADV antigens, whereas antigen-specific T cells were detected in 100% of CMV- seropositive donors, 73% of EBV- seropositive donors, and 73% of ADV-seropositive donors. At least 124 (61%) potential T cell donors were identified for each virus. Among the tested antigens, frequencies for CMVpp65 and EBVBZLF1 peptide pools were highest. Short-term in vitro peptide stimulation revealed that a donor response to a certain ADV- and EBV-derived peptide may not be determined without prior stimulation. A modified granzyme B ELISpot was used to detect T cell specificity and alloreactivity. Treatment with allogeneic virus-specific cytotoxic T lymphocytes from seropositive third-party donors may be a feasible therapeutic option for infections following cord-blood stem cell transplantation or hematopoietic stem cell transplantation from virus-seronegative donors.


Assuntos
Adenoviridae/imunologia , Citomegalovirus/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Transplante de Células-Tronco Hematopoéticas/métodos , Imunoterapia Adotiva/métodos , Linfócitos T Citotóxicos/imunologia , Condicionamento Pré-Transplante/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
18.
Transfusion ; 53(5): 1088-94, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23320406

RESUMO

BACKGROUND: Donors with short interdonation intervals (e.g., apheresis donors) have an increased risk of window period donations. The frequency of cytomegalovirus (CMV) window period donations is important information to decide whether selection of seronegative donors might be advantageous for patients at risk for transfusion-transmitted CMV infections (TT-CMV). STUDY DESIGN AND METHODS: CMV seroconversion in 93 donors with positive results in routine CMV antibody testing within at most 35 days after the last seronegative sample was evaluated by Western blot and/or a second antibody test. In donors with unconfirmed seroconversion, an additional later sample was tested. Concentration of CMV DNA was determined in pre- and postseroconversion samples. RESULTS: CMV seroconversion was confirmed in 12 donors (13%). Among these, the last seronegative sample was CMV DNA positive in three donors (25%, below 30 IU/mL). The first seropositive sample was CMV DNA positive in 10 donors (83%, maximum 1600 IU/mL). Both prevalence and median concentration of CMV DNA were higher in the first seropositive sample (p = 0.004 and p = 0.02), with maximum concentrations being reached about 2 weeks after seroconversion. No CMV DNA was detected in samples from donors with unconfirmed seroconversion. CONCLUSION: At least in donors with short interdonation intervals, most suspected CMV seroconversions are due to false-positive results of the screening test. As window period donations are rare and contain less CMV DNA than the first seropositive donation, avoidance of blood products from primarily seropositive donors is especially helpful to avoid TT-CMV if donors with short interdonation intervals are concerned.


Assuntos
Anticorpos Antivirais/sangue , Doadores de Sangue , Segurança do Sangue , Infecções por Citomegalovirus/transmissão , Citomegalovirus/imunologia , DNA Viral/sangue , Biomarcadores/sangue , Western Blotting , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/prevenção & controle , Reações Falso-Positivas , Humanos , Estudos Retrospectivos , Risco
19.
Transfusion ; 53(1): 211-20, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22612302

RESUMO

BACKGROUND: The objective was to investigate potential risks for apheresis donors associated with a triple-plateletpheresis (TP) program. STUDY DESIGN AND METHODS: Eleven hemapheresis centers randomly assigned 411 repeat donors (ratio, 1:1.2) to either double plateletpheresis (DP; 185 donors) or TP (226 donors) with a platelet (PLT) target content of at least 5.0×10(11) PLTs/DP and at least 7.5×10(11) PLTs/TP. The primary endpoint was procedure-related postapheresis PLT count of at least 150×10(9) /L (probability, ≥98%). Secondary endpoints were apheresis characteristics and donor adverse reactions. RESULTS: In 6 of 1133 DPs (0.5%) in 4 of 185 donors (2.2%) and in 20 of 1020 TPs (2.0%) in 14 of 226 donors (6.2%), postapheresis PLT counts were below 150×10(9) /L. There were marginal but significant differences in collection efficiency (DP, 69.2±9.1%; TP, 70.9±9.0%; p≤0.0001) and collection rate (DP, 10.4×10(9) ±2.3×10(9) PLTs/min; TP, 10.8×10(9) ±2.3×10(9) PLTs/min; p≤0.005). The PLT yields were 5.9×10(11) ±0.8×10(11) PLTs for DP and 8.3×10(11) ±0.9×10(11) PLT for TP (p≤0.0001) at processing times of 59±13 minutes (DP) versus 80±16 minutes (TP; p≤0.0001). Significant PLT recruitment (1.10±0.14 vs. 1.20±0.23; p<0.0001) was seen for both DP and TP. DP and TP did not differ with regard to venous access problems (VAPs) without discontinuation (3.8% for both), but DP induced fewer VAPs with discontinuation (1.1% vs. 3.0%; p<0.01). Mild citrate toxicity (1.7% vs. 3.9%; p<0.01) and circulatory reactions (0.4% vs. 2.2%; p<0.01) were more often noticed in TP, but caused no increase in discontinuations. CONCLUSIONS: TP results in an increase in mild donor reactions but does not significantly impair donor safety or product quality.


Assuntos
Plaquetoferese/efeitos adversos , Adulto , Áustria , Doadores de Sangue , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade
20.
J Clin Apher ; 26(6): 338-46, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22072548

RESUMO

OBJECTIVES: To determine the optimal time schedule for neutrophil collection after single mobilization with glycosylated recombinant granulocyte colony-stimulating factor (G-CSF, lenograstim) with or without dexamethasone (DXM). DONORS AND METHODS: In this prospective randomized trial, 26 healthy volunteers were randomly assigned to a single subcutaneous dose of lenograstim 6 µg/kg plus 8-mg DXM (G-CSF/DXM, n = 13) or placebo (G-CSF/placebo, n = 13). Hematological and biochemical parameters were analyzed before and 12, 15, 18, 21, 24, 27, 29, 36, 48, 60, 72, and 84 h and 7 and 30 days after mobilization. Six G-CSF/DXM subjects underwent standard neutrophil apheresis (NA) 12 and 36 h after mobilization. RESULTS: Polymorphonuclear neutrophil (PMN) counts 12 and 21 h after mobilization were 22.7 (16.6-32.8) × 10(9) /L and 22.4 (18.6-30.6) × 10(9) /L for G-CSF/placebo versus 33.1 (24.2-44.9) × 10(9) /L and 32.5 (17.4-39.6) × 10(9) /L for G-CSF/DXM. This mobilization plateau was followed by slow normalization at 72-84 h. The six NA subjects had median PMN yields of 62 (47-101) × 10(9) and 39 (23-42) × 10(9) per therapeutic unit. After the first apheresis, PMN counts sharply decreased to 21.1 (14.8-26.3) × 10(9) /L and then temporarily recovered to 25.9 (18.9-36.5) × 10(9) /L (P ≤ 0.001) over the next 8 h. CONCLUSIONS: Single doses of lenograstim with or without DXM induced a PMN plateau that lasted 9 h (12-21 h after mobilization), with PMN counts suitable for neutrophil collection. Lenograstim plus DXM made it possible to perform NA twice, 12 and 36 h after mobilization.


Assuntos
Dexametasona/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Mobilização de Células-Tronco Hematopoéticas/métodos , Leucaférese/métodos , Adulto , Doadores de Sangue , Feminino , Granulócitos/efeitos dos fármacos , Humanos , Cinética , Lenograstim , Masculino , Neutrófilos/efeitos dos fármacos , Estudos Prospectivos , Proteínas Recombinantes/administração & dosagem , Inquéritos e Questionários , Adulto Jovem
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