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1.
Transpl Immunol ; 84: 102045, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38641148

ABSTRACT

BACKGROUND: Allogeneic stem cell transplantation (SCT) is a critical therapy for haematological malignancy but may lead to acute and chronic graft versus host disease (GvHD). T-cell depletion with alemtuzumab, either in vivo or ex vivo, reduces the incidence of GvHD but is a risk factor for disease relapse and poor immune reconstitution. Natural killer (NK) cells are the first lymphocytes to recover. Classical NK cells make up >90% of the normal circulating population and can directly kill neoplastic or virally infected cells while the regulatory subset makes up <10%, secretes cytokines and is not cytotoxic. The recovery and balance of these subsets post SCT remains controversial, with most studies analysing patients who received unmanipulated grafts and in vivo immunosuppression. OBJECTIVE: The aim was to assess the early recovery of NK cells in 18 consecutive patients receiving ex vivo T-cell depleted SCT and to compare the results to 25 individuals receiving haploidentical non-T cell depleted grafts. METHODS: All patients received myeloablative conditioning. After stem cell collection, the stem cells of the T cell depleted group were treated "in the bag" with alemtuzumab (CAMPATH 1H) at a concentration of 1mg/108 mononuclear cells and thereafter immediately infused. For those receiving non-T cell depleted grafts, GvHD prophylaxis was with post infusion therapeutic doses of cyclophosphamide. Blood samples were collected at days 21, 28 and 90. Complete blood counts were performed on an automated analyser while lymphocyte and NK subsets were examined using multiparameter flowcytometry. NK cells were defined as lymphocytes which were CD3-/CD56+. The classical subset was recognised as CD56dim/CD16+ while the regulatory population as CD56bright/CD16-. The results for both transplant types were compared at all time points using SPSS v8 statistical software. RESULTS: The recovery of lymphocytes was slow in both groups. Those receiving non-T cell depleted grafts had significantly higher T cell counts at day 21 and 28 when compared to the T cell depleted group (P < 0.05). In contrast, NK cells in the ex vivo T-cell depleted patients recovered rapidly and by day 21 was no different to normal (p > 0.05), while the non-T cell depleted group had significantly decreased numbers (p < 0.001), only recovering at day 90. Both groups had abnormal NK cell subset ratios with significantly elevated percentages of regulatory cells (p < 0.05). However, significant differences were observed between the two groups with those receiving T cell depleted grafts having lower percentages of regulatory cells as well as higher numbers of classical NK cells at day 21 and 28 (p < 0.01). CONCLUSION: This study of ex vivo T-cell depleted SCT's demonstrates that NK cells recover quicker when compared to those receiving unfractionated grafts. These results may have implications for GvHD and the GvL effect which warrants further study.


Subject(s)
Alemtuzumab , Graft vs Host Disease , Hematopoietic Stem Cell Transplantation , Killer Cells, Natural , Lymphocyte Depletion , Transplantation, Homologous , Humans , Alemtuzumab/therapeutic use , Killer Cells, Natural/immunology , Male , Adult , Female , Middle Aged , Graft vs Host Disease/prevention & control , Graft vs Host Disease/immunology , Hematopoietic Stem Cell Transplantation/methods , Transplantation Conditioning/methods , T-Lymphocytes/immunology , Hematologic Neoplasms/therapy , Hematologic Neoplasms/immunology , Young Adult , Aged
2.
Ann Hematol ; 99(3): 579, 2020 03.
Article in English | MEDLINE | ID: mdl-32076824

ABSTRACT

The article "In the South African setting, HIV-associated Burkitt lymphoma is associated with frequent leukaemic presentation, complex cytogenetic karyotypes, and adverse clinical outcomes".

3.
Ann Hematol ; 99(3): 571-578, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31955214

ABSTRACT

South Africa (SA) has a high prevalence of human immunodeficiency virus (HIV) infection. People living with HIV are at markedly increased risk of developing Burkitt lymphoma (BL), which is characterized by the MYC translocation. There is a paucity of survival data of HIV-associated Burkitt lymphoma/leukaemia (HIV-BL) cases from SA, and the relationship between karyotype and outcomes has not been widely reported. Here we report the clinico-pathological characteristics of a cohort of cytogenetically confirmed HIV-BL cases. A retrospective, descriptive review was conducted of clinico-pathological features of HIV-BL patients newly diagnosed and treated between 2005 and 2014 at our tertiary academic institution in Cape Town. Only HIV-BL patients with cytogenetic evidence of a MYC translocation were included for analysis. A multivariable Cox proportional hazards model assessed the impact of variables on overall survival (OS). Forty-nine patients met inclusion criteria. Their median age was 37 years (IQR 30-43 years) and 57% (n = 28) were females. Their median CD4 count was 240 cells/µl (IQR 103-423 cells/µl). The majority, 61% (n = 30), had leukaemic presentation, and 20% (n = 10) had a complex karyotype on conventional karyotyping. Seventy-seven percent (n = 36) received various protocols of combination intensive chemotherapy, excluding rituximab. Their OS was 64% (95% CI 45-77%) at 6 months, and 34% (95% CI 17-51%) at 5 years. Leukaemic presentation and a complex karyotype gave a 2.7-fold (95% CI 1.0-6.7) and 2.6-fold (95% CI 1.1-6.6) increased risk of mortality respectively, which were statistical significant (p < 0.05). We report 49 newly diagnosed, cytogenetically confirmed HIV-BL patients at our institution over a 10-year period. There was a high proportion of complex karyotypes and leukaemic presentation, which both independently adversely affected survival. This may be due to differences in the pathobiology of HIV-BL that requires further study and could lead to therapeutic advances in this patient group.


Subject(s)
Abnormal Karyotype , Burkitt Lymphoma , HIV Infections , HIV-1 , Proto-Oncogene Proteins c-myc/genetics , Adult , Burkitt Lymphoma/drug therapy , Burkitt Lymphoma/etiology , Burkitt Lymphoma/genetics , Burkitt Lymphoma/mortality , Disease-Free Survival , Female , HIV Infections/complications , HIV Infections/drug therapy , HIV Infections/genetics , HIV Infections/mortality , Humans , Male , Retrospective Studies , Survival Rate
4.
Hematol Oncol Stem Cell Ther ; 13(4): 202-207, 2020 Dec.
Article in English | MEDLINE | ID: mdl-31181176

ABSTRACT

The first meeting of the African Blood and Marrow Transplantation (AfBMT) was held in Casablanca from April 19, 2018 to April 21, 2018, with the aim of fostering hematopoietic stem cell transplantation (HSCT) activity in Africa. Out of the 54 African countries, HSCT is available only in six (Algeria, Egypt, Morocco, Nigeria, South Africa, and Tunisia). During this meeting, African teams and international experts from the Worldwide Network for Blood and Marrow Transplantation (WBMT) gathered to share their experience and discussed ways to help fill the gap. Nurses and patients held their meeting in parallel. International support and collaboration can help by providing expertise adapted to local resources and regional population needs. Local engagement including government and private participants are necessary to initiate and develop local HSCT capability.


Subject(s)
Bone Marrow Transplantation , Hematopoietic Stem Cell Transplantation , Congresses as Topic , Morocco
5.
Cancer Immunol Immunother ; 68(1): 71-83, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30283982

ABSTRACT

Breast cancer remains one of the leading causes of cancer-associated death worldwide. Conventional treatment is associated with substantial toxicity and suboptimal efficacy. We, therefore, developed and evaluated the in vitro efficacy of an autologous dendritic cell (DC) vaccine to treat breast cancer. We recruited 12 female patients with stage 1, 2, or 3 breast cancer and matured their DCs with autologous tumour-specific lysate, a toll-like receptor (TLR)-3 and 7/8 agonist, and an interferon-containing cocktail. The efficacy of the vaccine was evaluated by its ability to elicit a cytotoxic T-lymphocyte response to autologous breast cancer cells in vitro. Matured DCs (≥ 60% upregulation of CD80, CD86, CD83, and CCR7) produced high levels of the Th1 effector cytokine, IL12-p70 (1.2 ng/ml; p < 0.0001), compared to DCs pulsed with tumour lysate, or matured with an interferon-containing cocktail alone. We further showed that matured DCs enhance antigen-specific CD8 + T-cell responses to HER-2 (4.5%; p < 0.005) and MUC-1 (19%; p < 0.05) tetramers. The mature DCs could elicit a robust and dose-dependent antigen-specific cytotoxic T-lymphocyte response (65%) which was tumoricidal to autologous breast cancer cells in vitro compared to T-lymphocytes that were primed with autologous lysate loaded-DCs (p < 0.005). Lastly, we showed that the mature DCs post-cryopreservation maintained high viability, maintained their mature phenotype, and remained free of endotoxins or mycoplasma. We have developed a DC vaccine that is cytotoxic to autologous breast cancer cells in vitro. The tools and technology generated here will now be applied to a phase I/IIa clinical trial.


Subject(s)
Breast Neoplasms/therapy , Cancer Vaccines/immunology , Dendritic Cells/immunology , Immunotherapy, Adoptive/methods , Adult , Aged , Breast Neoplasms/immunology , Breast Neoplasms/pathology , Coculture Techniques , Cytokines/immunology , Cytokines/metabolism , Female , Humans , Lymphocyte Activation/immunology , Middle Aged , T-Lymphocytes, Cytotoxic/immunology , Th1 Cells/immunology , Th1 Cells/metabolism , Tumor Cells, Cultured
6.
Bone Marrow Transplant ; 54(3): 402-417, 2019 03.
Article in English | MEDLINE | ID: mdl-30082852

ABSTRACT

Hematopoietic Stem Cell Transplantation (HSCT) activity was evaluated in the African (AFR)/EMRO region and compared to the global activity for the years 2006-2013. Data were obtained from 1570 teams in the 6 WHO continental regions. Of these, 29 (1.85%) of all teams were active in 12 of the 68 AFR/EMRO countries. They reported 2.331 (3.3%) of the worldwide 71.036 HSCT, and a transplant rate of 32.8 (TR; HSCT/10 million inhabitants; worldwide 128.5). This reflects still the lowest regional TR despite an increase of 90% since 2006. HSCT activity in AFR/EMRO countries was characterized by a higher use of allogeneic compared to autologous HSCT, an almost exclusive use of family donors, including haploidentical family donors. These findings contrast with the prevalence of autologous over allogeneic HSCT, and a higher frequency of unrelated HSCT in other parts of the world. Of note, the increase by 200% in HSCT for hemoglobinopathies from 2006 to 2013 (72 per year) in the AFR/EMRO region. This reflects the specific role of HSCT for these disease categories with high prevalence and incidence in the AFR/EMRO region. This report provides information for the competent authorities to foster adequate infrastructure. It urges transplant organization to optimize their cooperation.


Subject(s)
Hematopoietic Stem Cell Transplantation/methods , Africa , Hematopoietic Stem Cell Transplantation/trends , Humans , Retrospective Studies , Transplantation Conditioning/methods , Transplantation Conditioning/trends
7.
Ann Hematol ; 98(2): 381-389, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30397846

ABSTRACT

Human immunodeficiency virus (HIV) is associated with an increased risk of developing Hodgkin lymphoma (HL). South Africa (SA) has the highest HIV prevalence rate in the world. There is currently no outcome-based data for HIV-associated HL from SA. A bone marrow database was compiled of all bone marrow biopsies (BMB) reported at National Health Laboratory Service (NHLS) Groote Schuur Hospital (GSH) between January 2005 and December 2012. Patients who had a BMB performed for staging of HL or where HL was diagnosed on the BMB were included for further analysis. Clinical and laboratory data was extracted from medical and laboratory records. Primary outcome measures included histological subtype, bone marrow infiltration (BMI) by HL, CD4 count, HIV-viral load (HIV-VL), tuberculosis (TB) data, treatment with chemotherapy and 5-year overall survival (OS). The database included 6569 BMB and 219 patients of these had HL and were included for analysis. The median age at presentation (32 years) was similar in the HIV+ and HIV- populations. While males predominated in the HIV- group, females predominated in the HIV+ group (male:female ratio of 1.5:1 vs 0.7:1, respectively). The majority of patients (71%) were HIV negative (HIV-) and 29% were HIV positive (HIV+). The diagnosis of HL was made on BMB in 17% of cases. BMI was seen in 37% (82/219) overall, and was found in more HIV+ patients (61%; 39/64) than HIV- patients (28%; 43/155; p = 0.03). The histological subtype varied according to HIV status with nodular sclerosis classical Hodgkin lymphoma (NSCHL) being most frequent in the HIV- group and classical Hodgkin lymphoma (CHL)-unclassifiable the most frequent in the HIV+ group. HIV+ patients had a median CD4 count of 149 × 106/L and 39% were anti-retroviral therapy (cART) naive at HL diagnosis. HIV+ patients had received anti-TB therapy more frequently than HIV- patients (72% vs 17%; p = 0.007). More HIV+ patients did not receive chemotherapy than HIV- patients (31% vs 3%; p = 0.001). The 5-year OS was 56%. HIV+ patients with BMI had a 5-year OS of 18%. BMI, HIV status, low CD4 count, histological subtype and TB therapy had a statistical significant impact on 5-year OS (p < 0.01). The 5-year OS was 56%, with both BMI and HIV+ status being associated with poor survival. BMB provided the diagnosis of HL in 17% of cases, confirming its diagnostic utility in our setting. Our cohort showed similar survival outcomes to other countries in Africa, Asia and Central America with comparable socio-economic constraints to SA.


Subject(s)
Bone Marrow , HIV Seropositivity , HIV-1 , Hodgkin Disease , Adolescent , Adult , Aged , Aged, 80 and over , Biopsy , Bone Marrow/metabolism , Bone Marrow/pathology , Bone Marrow/virology , CD4 Lymphocyte Count , Disease-Free Survival , Female , HIV Seropositivity/blood , HIV Seropositivity/mortality , HIV Seropositivity/pathology , HIV Seropositivity/virology , Hodgkin Disease/blood , Hodgkin Disease/mortality , Hodgkin Disease/pathology , Hodgkin Disease/virology , Humans , Male , Middle Aged , Retrospective Studies , Sex Factors , South Africa/epidemiology , Survival Rate , Viral Load
8.
Clin Transl Med ; 5(1): 15, 2016 Mar.
Article in English | MEDLINE | ID: mdl-27056246

ABSTRACT

BACKGROUND: The major therapeutic benefit of hydroxyurea, the only FDA-approved pharmacologic treatment for sickle cell disease (SCD), is directly related to fetal hemoglobin (HbF) production that leads to significant reduction of morbidity and mortality. However, potential adverse effects such as infertility, susceptibility to infections, or teratogenic effect have been subject of concerns. Therefore, understanding HU molecular mechanisms of action, could lead to alternative therapeutic agents to increase HbF with less toxicity. This paper investigated whether HU-induced HbF could operate through post-transcriptional miRNAs regulation of BCL11A, KLF-1 and MYB, potent negative regulators of HbF. Both ex vivo differentiated primary erythroid cells from seven unrelated individuals, and K562 cells were treated with hydroxyurea (100 µM) and changes in BCL11A, KLF-1, GATA-1, MYB, ß- and γ-globin gene expression were investigated. To explore potential mechanisms of post-transcriptional regulation, changes in expression of seven targeted miRNAs, previously associated with basal γ-globin expression were examined using miScript primer assays. In addition, K562 cells were transfected with miScript miRNA inhibitors/anti-miRNAs followed by Western Blot analysis to assess the effect on HbF protein levels. Direct interaction between miRNAs and the MYB 3'-untranslated region (UTR) was also investigated by a dual-luciferase reporter assays. RESULTS: Down-regulation of BCL11A and MYB was associated with a sevenfold increase in γ-globin expression in both primary and K562 cells (p < 0.003). Similarly, KLF-1 was down-regulated in both cell models, corresponding to the repressed expression of BCL11A and ß-globin gene (p < 0.04). HU induced differential expression of all miRNAs in both cell models, particularly miR-15a, miR-16, miR-26b and miR-151-3p. An HU-induced miRNAs-mediated mechanism of HbF regulation was illustrated with the inhibition of miR-26b and -151-3p resulting in reduced HbF protein levels. There was direct interaction between miR-26b with the MYB 3'-untranslated region (UTR). CONCLUSIONS: These experiments have shown the association between critical regulators of γ-globin expression (MYB, BCL11A and KLF-1) and specific miRNAs; in response to HU, and demonstrated a mechanism of HbF production through HU-induced miRNAs inhibition of MYB. The role of miRNAs-mediated post-transcriptional regulation of HbF provides potential targets for new treatments of SCD that may minimize alterations to the cellular transcriptome.

9.
Lancet Haematol ; 2(3): e91-100, 2015 Mar.
Article in English | MEDLINE | ID: mdl-26687803

ABSTRACT

BACKGROUND: The transplantation of cells, tissues, and organs has been recognised by WHO as an important medical task for its member states; however, information about how to best organise transplantation is scarce. We aimed to document the activity worldwide from the beginning of transplantation and search for region adapted indications and associations between transplant rates and macroeconomics. METHODS: Between Jan 1, 2006, and Dec 31, 2014, the Worldwide Network for Blood and Marrow Transplantation collected data for the evolution of haemopoietic stem-cell transplantation (HSCT) activity and volunteer donors in the 194 WHO member states. FINDINGS: 953,651 HSCTs (553,350 [58%] autologous and 400,301 [42%] allogeneic) were reported by 1516 transplant centres from 75 countries. No transplants were done in countries with fewer than 300,000 inhabitants, a surface area less than 700 km(2), and a gross national income per person of US$1260 or lower. Use of HSCT increased from the first transplant in 1957 to almost 10,000 by 1985. We recorded a cumulative total of about 100,000 transplants by 1995, and an estimated 1 million by December, 2012. Unrelated donor registries contributed 22·3 million typed volunteer donors and 645,646 cord blood products by 2012. Numbers of allogeneic HSCTs increased in the past 35 years with no signs of saturation (R(2)=0·989). Transplant rates were higher in countries with more resources, more transplant teams, and an unrelated donor infrastructure. INTERPRETATION: Our findings show achievements and high unmet needs and give guidance for decisions; to grant access for patients, to provide a donor infrastructure, and to limit overuse by defining risk and region adapted indications for HSCT as an efficient and cost-effective approach for life-threatening, potentially curable diseases. FUNDING: Funding for this study was indirectly provided by support of the WBMT.


Subject(s)
Hematopoietic Stem Cell Transplantation , Registries , Data Collection , Global Health , Humans , Retrospective Studies
10.
Expert Rev Hematol ; 8(5): 669-79, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26327494

ABSTRACT

AIM: To report on molecular mechanisms of fetal hemoglobin (HbF) induction by hydroxyurea (HU) for the treatment of sickle cell disease. STUDY DESIGN: Systematic review. RESULTS: Studies have provided consistent associations between genomic variations in HbF-promoting loci and variable HbF level in response to HU. Numerous signal transduction pathways have been implicated, through the identification of key genomic variants in BCL11A, HBS1L-MYB, SAR1 or XmnI polymorphism that predispose the response to the treatment, and signal transduction pathways that modulate γ-globin expression (cAMP/cGMP; Giα/c-Jun N-terminal kinase/Jun; methylation and miRNA). Three main molecular pathways have been reported: i) Epigenetic modifications, transcriptional events and signaling pathways involved in HU-mediated response, ii) Signaling pathways involving HU-mediated response and iii) Post-transcriptional pathways (regulation by miRNAs). CONCLUSIONS: The complete picture of HU-mediated mechanisms of HbF production in Sickle Cell Disease remains elusive. Research on post-transcriptional mechanisms could lead to therapeutic targets that may minimize alterations to the cellular transcriptome.


Subject(s)
Anemia, Sickle Cell/drug therapy , Anemia, Sickle Cell/genetics , Antisickling Agents/therapeutic use , Fetal Hemoglobin/genetics , Hydroxyurea/therapeutic use , Anemia, Sickle Cell/metabolism , Antisickling Agents/pharmacology , Cyclic AMP/metabolism , Cyclic GMP/metabolism , Epigenesis, Genetic , Fetal Hemoglobin/metabolism , Gene Expression Regulation/drug effects , Genetic Variation , Humans , Hydroxyurea/pharmacology , MicroRNAs/genetics , Pharmacogenetics , Polymorphism, Single Nucleotide , RNA Processing, Post-Transcriptional , Signal Transduction/drug effects , gamma-Globins/genetics , gamma-Globins/metabolism
11.
S Afr Med J ; 105(5): 408-12, 2015 Apr 09.
Article in English | MEDLINE | ID: mdl-26242673

ABSTRACT

BACKGROUND: New agents are being used as second-line treatment for immune thrombocytopenia (ITP) and have brought into question the relevance of splenectomy for steroid-resistant ITP. METHODS: We retrospectively analysed 73 patients who underwent splenectomy for ITP at our institution over an 11-year period. The median follow-up period was 25 months; patients with follow-up of <1 month were excluded. The outcomes of splenectomy were compared in HIV-positive v. HIV-negative patients. RESULTS: The rate of complete response was 83%, and response was sustained for at least 1 year or until latest follow-up in 80% of patients. Twelve patients were HIV-positive. Splenectomy was laparoscopic in 43 patients (62%) with an overall 16% complication rate. The 90-day mortality rate was 1.38%. There was no statistically significant difference in response or complication rate in the HIV-positive patients. There was a statistically significant (p=0.003) poorer response to splenectomy in the patients with steroid-resistant ITP. CONCLUSION: Splenectomy is effective and safe irrespective of HIV status and remains an appropriate second-line treatment for ITP. Further research is needed to corroborate our finding of lower response in patients who are steroid-resistant, as this might be a subgroup of patients who may benefit from thrombopoietin agonists as second line therapy.


Subject(s)
HIV Infections/complications , Purpura, Thrombocytopenic, Idiopathic/therapy , Splenectomy , Thrombopoietin/therapeutic use , Adult , Female , Follow-Up Studies , HIV Infections/epidemiology , Humans , Laparoscopy , Male , Middle Aged , Platelet Count , Prevalence , Purpura, Thrombocytopenic, Idiopathic/epidemiology , Purpura, Thrombocytopenic, Idiopathic/etiology , Remission Induction , Retrospective Studies , South Africa/epidemiology , Time Factors , Treatment Outcome
12.
Hematol Oncol Stem Cell Ther ; 7(1): 32-40, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24480037

ABSTRACT

BACKGROUND AND OBJECTIVES: Despite the use of targeted therapy, chronic myelogenous leukemia (CML) currently remains incurable with drug therapy, with patients requiring life-long treatment. Developing either a vaccine to prevent the disease or another novel drug to specifically target and eradicate the CML cell will require the identification of CML-associated cell-surface markers and molecules that can bind specifically to the cell surface. In an attempt to discover peptides that bind specifically to cells in the early chronic phase of the disease, we used phage-display technology to identify heptapeptides that bind specifically to the surface of BCR/ABL-expressing fibroblasts. METHODS: An in vitro system using NIH3T3 stably transfected with pGD210 (BCR/ABL) was used as a model for the chronic phase of the disease. The cells were panned using a linear heptapeptide phage library (Ph.D 7.0) in a negative/positive panning strategy with NIH3T3 containing only the plasmid vector as the wild type control. RESULTS: We identified four novel peptides that were enriched through this technique. These peptides contained either multiple proline residues or serine/threonine-proline pairs and showed a confirmed binding preference for BCR/ABL+ fibroblasts. The peptide Y-R-A-P-W-P-P also showed a binding affinity for granulocytes from untreated CML patients. CONCLUSION: We have identified several novel peptides that can be used in future studies to identify specific CML cell-surface antigens or provide a novel drug-delivery mechanism.


Subject(s)
Cell Surface Display Techniques/methods , Fibroblasts/metabolism , Fusion Proteins, bcr-abl/metabolism , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism , Proline/metabolism , Serine/metabolism , Amino Acid Sequence , Animals , Clone Cells , Ligands , Mice , Molecular Sequence Data , NIH 3T3 Cells , Peptides/chemistry , Protein Binding , Sequence Alignment , Transfection
13.
N Engl J Med ; 369(24): 2313-23, 2013 Dec 12.
Article in English | MEDLINE | ID: mdl-24304002

ABSTRACT

BACKGROUND: Prophylactic factor replacement in patients with hemophilia B improves outcomes but requires frequent injections. A recombinant factor IX Fc fusion protein (rFIXFc) with a prolonged half-life was developed to reduce the frequency of injections required. METHODS: We conducted a phase 3, nonrandomized, open-label study of the safety, efficacy, and pharmacokinetics of rFIXFc for prophylaxis, treatment of bleeding, and perioperative hemostasis in 123 previously treated male patients. All participants were 12 years of age or older and had severe hemophilia B (endogenous factor IX level of ≤2 IU per deciliter, or ≤2% of normal levels). The study included four treatment groups: group 1 received weekly dose-adjusted prophylaxis (50 IU of rFIXFc per kilogram of body weight to start), group 2 received interval-adjusted prophylaxis (100 IU per kilogram every 10 days to start), group 3 received treatment as needed for bleeding episodes (20 to 100 IU per kilogram), and group 4 received treatment in the perioperative period. A subgroup of group 1 underwent comparative sequential pharmacokinetic assessments of recombinant factor IX and rFIXFc. The primary efficacy end point was the annualized bleeding rate, and safety end points included the development of inhibitors and adverse events. RESULTS: As compared with recombinant factor IX, rFIXFc exhibited a prolonged terminal half-life (82.1 hours) (P<0.001). The median annualized bleeding rates in groups 1, 2, and 3 were 3.0, 1.4, and 17.7, respectively. In group 2, 53.8% of participants had dosing intervals of 14 days or more during the last 3 months of the study. In groups 1, 2 and 3, 90.4% of bleeding episodes resolved after one injection. Hemostasis was rated as excellent or good during all major surgeries. No inhibitors were detected in any participants receiving rFIXFc; in groups 1, 2, and 3, 73.9% of participants had at least one adverse event, and serious adverse events occurred in 10.9% of participants. These events were mostly consistent with those expected in the general population of patients with hemophilia. CONCLUSIONS: Prophylactic rFIXFc, administered every 1 to 2 weeks, resulted in low annualized bleeding rates in patients with hemophilia B. (Funded by Biogen Idec; ClinicalTrials.gov number, NCT01027364.).


Subject(s)
Factor IX/therapeutic use , Hemophilia B/drug therapy , Recombinant Fusion Proteins/therapeutic use , Adolescent , Adult , Aged , Child , Factor IX/adverse effects , Factor IX/pharmacokinetics , Female , Half-Life , Hemophilia B/metabolism , Hemorrhage/prevention & control , Humans , Male , Middle Aged , Recombinant Fusion Proteins/adverse effects , Recombinant Fusion Proteins/pharmacokinetics , Young Adult
14.
Biol Blood Marrow Transplant ; 19(12): 1753-9, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24120379

ABSTRACT

The immunodepleting effects of alemtuzumab on peripheral blood progenitor cell (PBPC) grafts for stem cell transplantation need to be better defined. The optimal graft cell concentration, antibody dose, need for complement, and whether alemtuzumab is infused with the graft during transplantation remain unclear. PBPC from 6 normal allogeneic stem cell donors harvested by apheresis were first quantitated and the cellular content defined by flow cytometry. Mononuclear cells were then incubated with incremental concentrations of alemtuzumab (.00001, .0001, .001, and .01 mg/mL) for 30 minutes at 20°C or in cell dose responses with 1, 5, and 10 × 10(6) mononuclear cells/mL added to a fixed dose of .001 mg/mL of alemtuzumab with or without a source of complement. Cells were enumerated and analyzed by flow cytometry before and after exposure to alemtuzumab. To determine the presence of unbound anti-CD52, the supernatant of the cell dose responses were tested using the ELISA assay. Selected CD34+ lineage-negative cells were incubated with antibody at the same working concentrations and conditions and cultured in granulocyte-macrophage colony-forming unit assay. The colony numbers were compared with control cultures devoid of the antibody. Incremental concentrations of alemtuzumab led to a significant (2 log) reduction in CD3, CD4, and CD8 populations, which plateaued at .001 mg/mL. Addition of complement led to a further significant reduction in the CD4 and CD8 cells. The maximum CD4 (3 log) and CD8 (2 log) cell death was obtained at 10 × 10(6) cells/mL. Analysis of supernatants for soluble alemtuzumab by ELISA showed a significant reduction in the free antibody concentration when the cell number was increased from 1 to 10 × 10(6) cells/mL implying utilization/binding of the antibody by target cells. Incremental concentrations of alemtuzumab did not affect the number of granulocyte-macrophage colony-forming units. Alemtuzumab depletes all cells expressing the CD52 antigen and has higher activity on CD3, CD8, and particularly on CD4 cells, which are depleted in excess of 2 logs. From this study, we were able to derive that the optimal cell kill in the graft without detectable free alemtuzumab in the supernatant can be achieved with 1 mg of antibody per 100 mL containing 10 × 10(9) cells and active complement (AB serum).


Subject(s)
Antibodies, Monoclonal, Humanized/pharmacology , Hematopoietic Stem Cell Transplantation/methods , Hematopoietic Stem Cells/drug effects , Hematopoietic Stem Cells/immunology , Lymphocyte Depletion/methods , Alemtuzumab , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Graft vs Host Disease/immunology , Humans , T-Lymphocytes/drug effects , T-Lymphocytes/immunology
15.
Hematol Oncol Stem Cell Ther ; 6(2): 49-57, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23714180

ABSTRACT

INTRODUCTION: Research has implied that the immune system plays a role in the pathogenesis of MDS and that T-cells are reacting to tumour antigen present on the surface of the malignant cells. This could imply that the immune system could be utilized to generate immune based therapy. The aim of this pilot study was to examine the feasibility of studying this further by analysing the interaction of dendritic cells with T-cells in a small cohort of MDS patients. METHODS: Dendritic cells were generated in 6 MDS patients and 9 controls by culturing monocytes with GM-CSF and IL-4. After activation with LPS and TNFα, the dendritic cells were analyzed for expression of co-stimulatory and activation antigens. Thereafter, they were co-cultured with T-cells and the T-cell response was examined by measuring the % change in expression of the activation antigen CD69. RESULTS: MDS MoDC had reduced expression of HLA-DR (p=0.006), CD11c (p=0.0004), CD80 (p=0.03) and CD86 (p=0.003), while resting T-cells from MDS patients had higher expression of the activation antigen CD69 on all subsets. The % change in CD69 expression increased significantly for both the control and MDS T-cells after co-culture with allogeneic dendritic cells, however this change was lower in the MDS group. Despite the increased CD69 expression prior to culture, MDS MoDC significantly up-regulated CD69 expression on autologous T-cells to values that were statistically higher than control cells. CONCLUSION: This initial study suggests that the T-cells in MDS are able to respond to dendritic cells and are therefore probably not part of the malignant clone. It further implies that the dendritic cell population could be capable of presenting antigen and initiating an immune response and therefore further study is both feasible and warranted.


Subject(s)
Dendritic Cells/cytology , Monocytes/cytology , T-Lymphocytes/cytology , Adult , Aged , Antigens, CD/metabolism , Antigens, Differentiation, T-Lymphocyte/metabolism , Cells, Cultured , Coculture Techniques , Cohort Studies , Female , Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology , Humans , Immunotherapy , Interleukin-4/pharmacology , Lectins, C-Type/metabolism , Lipopolysaccharides/pharmacology , Male , Middle Aged , Monocytes/drug effects , Myelodysplastic Syndromes/metabolism , Myelodysplastic Syndromes/pathology , Myelodysplastic Syndromes/therapy , Pilot Projects , T-Lymphocytes/drug effects , T-Lymphocytes/metabolism , Tumor Necrosis Factor-alpha/pharmacology
16.
Biol Blood Marrow Transplant ; 19(4): 584-8, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23270985

ABSTRACT

Immunodepletion with alemtuzumab is an effective strategy for preventing graft-versus-host disease after allogeneic stem cell transplantation (SCT), but it may be associated with graft failure. We tested the effectiveness of a purine analog-based reduced-intensity conditioning combination in patients undergoing allogeneic SCT for bone marrow aplasia. Patients with severe marrow aplasia who had a tissue-compatible sibling donor were conditioned with fludarabine 30 mg/m(2) for 5 days and cyclophosphamide 120 mg/kg. Stem cells from HLA-identical sibling donors were mobilized with filgrastim, and the harvested blood concentrates were incubated ex vivo with alemtuzumab. After graft infusion, patients received therapeutic doses of cyclosporine up to day 90. The primary objective of this study was to examine the proportion of patients who achieved engraftment and overall survival. Secondary objectives were the rates of graft-versus-host disease, posttransplantation infections, and graft failure. The study group comprised 30 patients who received a total of 31 cytokine-mobilized blood stem cell transplantations. The median CD34(+) cell dose infused was 4.99 × 10(6)/kg. All patients engrafted at a median of 12 days post-SCT. Two patients exhibited delayed graft failure, at 3 months and 7 months post-SCT, and required retransplantation or donor lymphocyte infusion to reestablish full-donor chimerism. At a median of 1,560 days post-SCT, all patients survived and were transfusion-free. We confirm that the combination of purine analog and cyclophosphamide is adequate for engraftment of grafts immunodepleted with alemtuzumab. This strategy is associated with excellent outcomes.


Subject(s)
Anemia, Aplastic/therapy , Antibodies, Monoclonal, Humanized/therapeutic use , Cyclophosphamide/therapeutic use , Graft vs Host Disease/therapy , Hematopoietic Stem Cell Transplantation , Myeloablative Agonists/therapeutic use , Transplantation Conditioning/methods , Vidarabine/analogs & derivatives , Adolescent , Adult , Alemtuzumab , Anemia, Aplastic/immunology , Anemia, Aplastic/pathology , Antibodies, Monoclonal, Humanized/pharmacology , Cells, Cultured , Child , Female , Graft Survival/drug effects , Graft Survival/immunology , Graft vs Host Disease/diagnosis , Graft vs Host Disease/immunology , Hematopoietic Stem Cells/drug effects , Hematopoietic Stem Cells/immunology , Humans , Male , Middle Aged , Secondary Prevention , Transplantation, Homologous , Treatment Outcome , Vidarabine/therapeutic use
17.
Leuk Res ; 35(9): 1200-4, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21474180

ABSTRACT

Our aim was to examine in 17 patients with MDS the effects of PMA activated and non-activated autologous lymphocytes on selected bone marrow CD34+ progenitors, in dose response studies. We used a double layer culture technique. Compared with controls, there was no difference in the colony growth promoting capacity of autologous PMA stimulated or unstimulated blood lymphocytes from MDS patients. In addition, similar to control studies, increasing numbers of lymphocytes, (0, 1×10(5), 1×10(6)) led to a corresponding increase in the number of CFU-GM (p=0.04). We conclude that MDS blood mononuclear cells have the ability to stimulate colony growth of autologous CD34+ cells while these selected progenitors show a proliferative capacity that is similar to normal when they are isolated from the bone marrow accessory cells.


Subject(s)
Antigens, CD34/metabolism , Bone Marrow Cells/physiology , Cell Proliferation , Myelodysplastic Syndromes/metabolism , Adult , Aged , Aged, 80 and over , Bone Marrow Cells/metabolism , Bone Marrow Cells/pathology , Case-Control Studies , Cell Culture Techniques/methods , Cells, Cultured , Clone Cells/metabolism , Female , Humans , Male , Middle Aged
18.
Biol Blood Marrow Transplant ; 17(6): 875-84, 2011 Jun.
Article in English | MEDLINE | ID: mdl-20870030

ABSTRACT

For patients with acute myelogenous leukemia (AML) who are unable to secure an acceptable HLA donor, the role of autologous stem cell transplantation (auto-SCT) has remained controversial. Its effectiveness remains unclear as, when analyzed on intention-to-treat strategies, a significant number do not undergo the procedure, whereas others seem to fail therapy from pretransplant recurrences. To improve our counseling to our patients on these 2 therapeutic options, we compared the outcome of patients in first remission of AML who actually underwent autologous or allogeneic transplantation. The choice for the type of graft was based on availability of HLA identical siblings. Patients received myeloablative conditioning followed by allogeneic or autologous cytokine mobilized peripheral blood stem cell transplantation. For prophylaxis of graft-versus-host disease (GVHD), grafts were incubated ex vivo with anti-CD52 antibodies and patients were prescribed cyclosporin until day 90. Patients were stratified by clinical and laboratory factors as well as cytogenetic risk. The endpoints were treatment-related mortality (TRM), disease-free survival (DFS), and overall survival (OS). The median presentation age for both transplant groups was 35 (14-60) years. Of the 112 consecutive patients achieving remission, autologous or allogeneic grafts were transplanted to 43 and 32 patients, respectively. There was no significant difference in the presentation clinical features, laboratory parameters, marrow morphology, or proportion of low and intermediate cytogenetic risk for both transplant options. Treatment mortality as well as relapse rate was similar (14% and 15%; 39% and 27%, respectively). At a median of 1609 and 1819 posttransplant days, 56% and 63% in each group survived. In univariate analysis performance status, cytogenetic risk, morphologic features of dysplasia, blast count, and lactate dehydrogenase (LDH) were significant factors for survival. Although for the entire group there was no difference in survival between both modalities, all patients with unfavorable cytogenetics receiving an autologous graft died of disease recurrence (3-year survival 35% versus 0%; P = .05). We conclude that patients with AML who have low or intermediate cytogenetic risk undergoing myeloablative conditioning followed by autologous or allogeneic T cell-depleted stem cell transplantation appeared to have similar outcome. However, those with unfavorable karyotype are unlikely to be cured with autologous grafts and are candidates for experimental modalities.


Subject(s)
Graft vs Host Disease/prevention & control , Hematopoietic Stem Cell Transplantation , Leukemia, Myeloid, Acute/immunology , Leukemia, Myeloid, Acute/pathology , Adult , Antibodies, Monoclonal/immunology , Antigens, CD/immunology , Antigens, Neoplasm/immunology , CD52 Antigen , Chromosome Aberrations , Cyclosporine/pharmacology , Disease-Free Survival , Female , Glycoproteins/immunology , Graft vs Host Disease/mortality , HLA Antigens/analysis , Humans , Karyotyping , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/mortality , Leukemia, Myeloid, Acute/therapy , Male , Recurrence , Retrospective Studies , Risk Factors , Siblings , South Africa , Transplantation Conditioning/methods , Transplantation, Autologous , Transplantation, Homologous , Treatment Outcome
19.
Biol Blood Marrow Transplant ; 16(10): 1402-10, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20385248

ABSTRACT

We studied in patients with multiple myeloma (MM) the efficacy, cost-effectiveness, and toxicity of a strategy of submyeloablative doses of Mel and stem cell support in the ambulatory setting, followed by a standard myeloablative dose transplant. Patients with recently diagnosed symptomatic MM received dexamethazone to induce clinical response. Cytokine mobilized peripheral blood progenitor cells (PBPC) were split into 2 aliquots and cryopreserved. Patients then received Mel 100 mg/m(2) (Mel100) and infusion of the first PBPC aliquot in an ambulatory facility. Individuals received standard neutropenia prophylaxis and no growth factor support, but were seen regularly at the clinic until recovery. The cost of this step was calculated in a cohort of 23 patients where information for the expenditure was available. Six months later patients were conditioned in the hospital with Mel 200 mg/m(2) (Mel 200) followed by nfusion of the second aliquot. This study tested the cost, effectiveness, and the toxicity of out-patient-based transplantation, as well as the rate of response (complete remission [CR], very good partial remission [VGPR], partial remission [PR], and stable disease [SD]) and overall survival (OS) of this strategy. Twenty-six female and 16 male patients, with a median age of 53 years (range: 33-68 years) and median Salmon & Durie clinical disease stage III (range: II-III) were studied. The paraprotein was IgA in 17%, IgG in 52%, and light chains in 26%. The median harvested CD34(+) x 10(6) cells/kg was 12.03 (2.25-55.4). The median interval between the 2 transplant procedures was 239 (105-376) days. The median Karnofsky presentation score was 40%, but improved to 80% after the Mel 100 and was 90% following Mel 200. Subsequent to MEL 100 response was complete (CR) in 7 and it was VGPR in 9. Mel 100 grade 3-4 toxicity was mainly hematologic, but 15 (36%) required hospital admission for a median of 5 days. The median cost of MEL100 and corresponding supportive therapy was U.S. $2,142.35. In addition, the total median cost of those who needed admission to hospital was U.S. $6,042.78. Thus, pooling costs from patients who needed or did not need admissions the average cost of this strategy was U.S. $3,546.50 per patient. Among Mel 200 patients, except for hematologic toxicity, no patient had greater than grade 2 side effects. On completion of the program, 20 (48%) patients achieved CR, a further 14 (33%) had VGPR, whereas 6 had PR. At a median follow-up of 659 days there were 8 deaths, 1 (2%) was related to the treatment procedures and 6 from disease progression; thus, the 1000 days OS was 73%. Significant adverse factors included older age, lower presentation Hb, and lower Karnofsky %. Nonparametric testing confirmed that good performance scores and VGPR or CR were associated with more favorable outcome. Importantly, these satisfactory results were obtained in the absence of the new biologic cell modifiers. Mel 100 was well tolerated in the outpatient setting and the overall strategy seems to be effective in inducing durable responses with acceptable toxicity.


Subject(s)
Melphalan/administration & dosage , Multiple Myeloma/surgery , Myeloablative Agonists/administration & dosage , Peripheral Blood Stem Cell Transplantation/statistics & numerical data , Transplantation Conditioning/methods , Adult , Aged , Ambulatory Care/economics , Combined Modality Therapy , Dexamethasone/therapeutic use , Disease Progression , Disease-Free Survival , Drug Costs , Female , Filgrastim , Follow-Up Studies , Granulocyte Colony-Stimulating Factor/pharmacology , Hospital Costs , Humans , Karnofsky Performance Status , Male , Melphalan/adverse effects , Melphalan/economics , Melphalan/therapeutic use , Middle Aged , Multiple Myeloma/drug therapy , Multiple Myeloma/economics , Multiple Myeloma/mortality , Myeloablative Agonists/adverse effects , Myeloablative Agonists/economics , Myeloablative Agonists/therapeutic use , Recombinant Proteins , Remission Induction , South Africa , Survival Analysis , Transplantation Conditioning/adverse effects , Transplantation Conditioning/economics , Transplantation, Autologous , Treatment Outcome
20.
J Clin Oncol ; 27(24): 3951-8, 2009 Aug 20.
Article in English | MEDLINE | ID: mdl-19620487

ABSTRACT

PURPOSE: To analyze the long-term outcome in terms of nonrelapse mortality (NRM), relapse rate (RR), progression-free survival (PFS), and overall survival (OS) in patients with angioimmunoblastic T-cell lymphoma (AITL) treated with allogeneic stem-cell transplantation (alloSCT). PATIENTS AND METHODS: Forty-five patients with AITL who had undergone an alloSCT between January 1998 and December 2005 and were registered in the European Group for Blood and Marrow Transplantation database were analyzed. Median age was 48 years (range, 23 to 68 years), 34 patients had received > or = two lines of chemotherapy before alloSCT, and 11 patients had experienced treatment failure with a prior autologous stem-cell transplantation. Twenty-five patients underwent a myeloablative alloSCT, and 20 underwent a reduced-intensity alloSCT. Donors were HLA-identical siblings in 26 patients. Twenty-seven patients were allografted in chemotherapy-sensitive disease, and 18 were allografted in refractory disease. RESULTS: The cumulative incidence of NRM was 18%, 22%, and 25% at 3, 6, and 12 months, respectively. Patients with poor performance status had a significantly higher NRM (P = .01). RR was estimated as 16% and 20% at 2 and 3 years, respectively, and was lower in patients developing chronic graft-versus-host disease (cGVHD). PFS and OS rates were 62% and 53% and 66% and 64% at 1 and 3 years, respectively, and were significantly better in chemotherapy-sensitive patients. CONCLUSION: AlloSCT represents a valid therapeutic option for patients with AITL. Both the lower RR after transplantation as well as the decreased RR in patients developing cGVHD after the alloSCT suggests the existence of a clinically relevant graft-versus-lymphoma effect.


Subject(s)
Hematopoietic Stem Cell Transplantation , Lymphoma, T-Cell, Peripheral/therapy , Adult , Aged , Female , Graft vs Host Disease/epidemiology , Humans , Lymphoma, T-Cell, Peripheral/mortality , Male , Middle Aged , Recurrence , Retrospective Studies , Transplantation, Homologous
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