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1.
Mol Ther ; 2024 Apr 06.
Article En | MEDLINE | ID: mdl-38582964

We previously demonstrated the antitumor effectiveness of transiently T cell receptor (TCR)-redirected T cells recognizing a frameshift mutation in transforming growth factor beta receptor 2. We here describe a clinical protocol using mRNA TCR-modified T cells to treat a patient with progressive, treatment-resistant metastatic microsatellite instability-high (MSI-H) colorectal cancer. Following 12 escalating doses of autologous T cells electroporated with in-vitro-transcribed Radium-1 TCR mRNA, we assessed T cell cytotoxicity, phenotype, and cytokine production. Tumor markers and growth on computed tomography scans were evaluated and immune cell tumor infiltrate at diagnosis assessed. At diagnosis, tumor-infiltrating CD8+ T cells had minimal expression of exhaustion markers, except for PD-1. Injected Radium-1 T cells were mainly naive and effector memory T cells with low expression of exhaustion markers, except for TIGIT. We confirmed cytotoxicity of transfected Radium-1 T cells against target cells and found key cytokines involved in tumor metastasis, growth, and angiogenesis to fluctuate during treatment. The treatment was well tolerated, and despite his advanced cancer, the patient obtained a stable disease with 6 months survival post-treatment. We conclude that treatment of metastatic MSI-H colorectal cancer with autologous T cells electroporated with Radium-1 TCR mRNA is feasible, safe, and well tolerated and that it warrants further investigation in a phase 1/2 study.

2.
Adv Healthc Mater ; 12(32): e2300640, 2023 Dec.
Article En | MEDLINE | ID: mdl-37781993

Intra-portal islet transplantation is currently the only clinically approved beta cell replacement therapy, but its outcome is hindered by limited cell survival due to a multifactorial reaction against the allogeneic tissue in liver. Adipose-derived stromal cells (ASCs) can potentially improve the islet micro-environment by their immunomodulatory action. The challenge is to combine both islets and ASCs in a relatively easy and consistent long-term manner in a deliverable scaffold. Manufacturing the 3D bioprinted double-layered scaffolds with primary islets and ASCs using a mix of alginate/nanofibrillated cellulose (NFC) bioink is reported. The diffusion properties of the bioink and the supportive effect of human ASCs on islet viability, glucose sensing, insulin secretion, and reducing the secretion of pro-inflammatory cytokines are demonstrated. Diabetic mice transplanted with islet-ASC scaffolds reach normoglycemia seven days post-transplantation with no significant difference between this group and the group received islets under the kidney capsules. In addition, animals transplanted with islet-ASC scaffolds stay normoglycemic and show elevated levels of C-peptide compared to mice transplanted with islet-only scaffolds. The data present a functional 3D bioprinted scaffold for islets and ASCs transplanted to the extrahepatic site and suggest a possible role of ASCs on improving the islet micro-environment.


Diabetes Mellitus, Experimental , Insulin-Secreting Cells , Islets of Langerhans Transplantation , Islets of Langerhans , Mice , Humans , Animals , Diabetes Mellitus, Experimental/therapy , Diabetes Mellitus, Experimental/metabolism , Insulin Secretion , Insulin-Secreting Cells/metabolism , Stromal Cells/metabolism , Islets of Langerhans/metabolism , Insulin/metabolism
3.
Leukemia ; 37(9): 1842-1849, 2023 09.
Article En | MEDLINE | ID: mdl-37507426

Intensive induction chemotherapy achieves complete remissions (CR) in >60% of patients with acute myeloid leukemia (AML) but overall survival (OS) is poor for relapsing patients not eligible for allogeneic hematopoietic stem cell transplantation (allo-HSCT). Oral azacytidine may be used as maintenance treatment in AML in first remission, but can be associated with substantial side effects, and less toxic strategies should be explored. Twenty AML patients in first CR (CR1) ineligible for allo-HSCT were treated with FDC101, an autologous RNA-loaded mature dendritic cell (mDC) vaccine expressing two leukemia-associated antigens (LAAs). Each dose consisted of 2.5-5 × 106 mDCs per antigen, given weekly until week 4, at week 6, and then monthly, during the 2-year study period. Patients were followed for safety and long-term survival. Treatment was well tolerated, with mild and transient injection site reactions. Eleven of 20 patients (55%) remained in CR, while 4 of 6 relapsing patients achieved CR2 after salvage therapy and underwent allo-HSCT. OS at five years was 75% (95% CI: 50-89), with 70% of patients ≥60 years of age being long-term survivors. Maintenance therapy with this DC vaccine was well tolerated in AML patients in CR1 and was accompanied by encouraging 5-year long-term survival.


Hematopoietic Stem Cell Transplantation , Leukemia, Myeloid, Acute , Humans , Induction Chemotherapy , Transplantation, Homologous , Leukemia, Myeloid, Acute/therapy , Remission Induction , Recurrence , Dendritic Cells , Retrospective Studies , Antigens, Neoplasm , WT1 Proteins/genetics
4.
Front Oncol ; 12: 1031232, 2022.
Article En | MEDLINE | ID: mdl-36439452

Background: Adoptive cellular therapy (ACT) with genetically modified T cells aims to redirect T cells against resistant cancers through introduction of a T cell receptor (TCR). The Radium-4 TCR was isolated from a responding patient in a cancer vaccination study and recognizes the enzymatic component of human Telomerase Reverse Transcriptase (hTERT) presented on MHC class II (HLA-DP04). hTERT is a constitutively overexpressed tumor-associated antigen present in most human cancers, including non-small-cell lung cancer (NSCLC), which is the second most common type of cancer worldwide. Treatment alternatives for relapsing NSCLC are limited and survival is poor. To improve patient outcome we designed a TCR-based ACT study targeting hTERT. Methods: T-RAD is a phase I/II study to evaluate the safety and efficacy of Radium-4 mRNA electroporated autologous T cells in the treatment of metastatic NSCLC with no other treatment option. Transient TCR expression is applied for safety considerations. Participants receive two intravenous injections with escalating doses of redirected T cells weekly for 6 consecutive weeks. Primary objectives are safety and tolerability. Secondary objectives include progression-free survival, time to progression, overall survival, patient reported outcomes and overall radiological response. Discussion: Treatment for metastatic NSCLC is scarce and new personalized treatment options are in high demand. hTERT is a tumor target applicable to numerous cancer types. This proof-of-concept study will explore for the first time the safety and efficacy of TCR mRNA electroporated autologous T cells targeting hTERT. The T-RAD study will thus evaluate an attractive candidate for future immunotherapy of solid tumors.

5.
Prostate ; 82(2): 245-253, 2022 02.
Article En | MEDLINE | ID: mdl-34762317

BACKGROUND: Patients with high-risk prostate cancer (PC) can experience biochemical relapse (BCR), despite surgery, and develop noncurative disease. The present study aimed to reduce the risk of BCR with a personalized dendritic cell (DC) vaccine, given as adjuvant therapy, after robot-assisted laparoscopic prostatectomy (RALP). METHODS: Twelve weeks after RALP, 20 patients with high-risk PC and undetectable PSA received DC vaccinations for 3 years or until BCR. The primary endpoint was the time to BCR. The immune response was assessed 7 weeks after surgery (baseline) and at one-time point during the vaccination period. RESULTS: Among 20 patients, 11 were BCR-free over a median of 96 months (range: 84-99). The median time from the end of vaccinations to the last follow-up was 57 months (range: 45-60). Nine patients developed BCR, either during (n = 4) or after (n = 5) the vaccination period. Among five patients diagnosed with intraductal carcinoma, three experienced early BCR during the vaccination period. All patients that developed BCR remained in stable disease within a median of 99 months (range: 74-99). The baseline immune response was significantly associated with the immune response during the vaccination period (p = 0.015). For patients diagnosed with extraprostatic extension (EPE), time to BCR was longer in vaccine responders than in non-responders (p = 0.09). Among 12 patients with the International Society of Urological Pathology (ISUP) grade 5 PC, five achieved remission after 84 months, and all mounted immune responses. CONCLUSION: Patients diagnosed with EPE and ISUP grade 5 PC were at particularly high risk of developing postsurgical BCR. In this subgroup, the vaccine response was related to a reduced BCR incidence. The vaccine was safe, without side effects. This adjuvant first-in-man Phase I/II DC vaccine study showed promising results. DC vaccines after curative surgery should be investigated further in a larger cohort of patients with high-risk PC.


Cancer Vaccines/administration & dosage , Neoplasm Metastasis/prevention & control , Prostate , Prostatectomy/adverse effects , Prostatic Neoplasms , Secondary Prevention/methods , Biomarkers/blood , Dendritic Cells/immunology , Humans , Male , Middle Aged , Outcome Assessment, Health Care/methods , Outcome Assessment, Health Care/statistics & numerical data , Prostate/immunology , Prostate/pathology , Prostate-Specific Antigen/blood , Prostatectomy/methods , Prostatic Neoplasms/blood , Prostatic Neoplasms/mortality , Prostatic Neoplasms/pathology , Prostatic Neoplasms/surgery , Survival Analysis , Time , Vaccines, Synthetic/administration & dosage
6.
Cell Med ; 9(3): 103-116, 2017.
Article En | MEDLINE | ID: mdl-28713640

Adipose-derived mesenchymal stem cells (ASCs) release factors beneficial for islets in vitro and protect against hyperglycemia in rodent models of diabetes. Oxygen tension has been shown to induce metabolic changes and alter ASCs' release of soluble factors. The effects of hypoxia on the antidiabetic properties of ASCs have not been explored. To investigate this, we incubated human ASCs for 48 h in 21% (normoxia) or 1% O2 (hypoxia) and compared viability, cell growth, surface markers, differentiation capability, and soluble factors in the conditioned media (CM). Human islets were exposed to CM from ASCs incubated in either normoxia or hypoxia, and islet function and apoptosis after culture with or without proinflammatory cytokines were measured. To test hypoxic preconditioned ASCs' islet protective effects in vivo, ASCs were incubated for 48 h in normoxia or hypoxia before being injected into Balb/c Rag 1-/- immunodeficient mice with streptozotocin-induced insulitis. Progression of diabetes and insulin content of pancreas were measured. We found that incubation in hypoxia was well tolerated by ASCs and that levels of VEGF-A, FGF-2, and bNGF were elevated in CM from ASCs incubated in hypoxia compared to normoxia, while levels of HGF, IL-8, and CXCL1 were reduced. CM from ASCs incubated in hypoxia significantly improved human islet function and reduced apoptosis after culture, and reduced cytokine-induced apoptosis. In our mouse model, pancreas insulin content was higher in both groups receiving ASCs compared to control, but the mice receiving preconditioned ASCs had lower random and fasting blood glucose, as well as improved oral glucose tolerance compared to untreated mice. In conclusion, our in vitro results indicate that the islet protective potential of ASCs improves in hypoxia, and we give insight into factors involved in this. Finally we show that hypoxic preconditioning potentiates ASCs' antidiabetic effect in vivo.

7.
Bipolar Disord ; 18(8): 657-668, 2016 12.
Article En | MEDLINE | ID: mdl-27995733

OBJECTIVES: Reduced dentate gyrus volume and increased oxidative stress have emerged as potential pathophysiological mechanisms in bipolar disorder. However, the relationship between dentate gyrus volume and peripheral oxidative stress markers remains unknown. Here, we examined dentate gyrus-cornu ammonis (CA) 4 volume longitudinally in patients with bipolar II disorder (BD-II) and healthy controls and investigated whether BD-II is associated with elevated peripheral levels of oxidative stress. METHODS: We acquired high-resolution structural 3T-magnetic resonance imaging (MRI) images and quantified hippocampal subfield volumes using an automated segmentation algorithm in individuals with BD-II (n=29) and controls (n=33). The participants were scanned twice, at study inclusion and on average 2.4 years later. In addition, we measured peripheral levels of two lipid peroxidation markers (4-hydroxy-2-nonenal [4-HNE] and lipid hydroperoxides [LPH]). RESULTS: First, we demonstrated that the automated hippocampal subfield segmentation technique employed in this work reliably measured dentate gyrus-CA4 volume. Second, we found a decreased left dentate gyrus-CA4 volume in patients and that a larger number of depressive episodes between T1 and T2 predicted greater volume decline. Finally, we showed that 4-HNE was elevated in BD-II and that 4-HNE was negatively associated with left and right dentate gyrus-CA4 volumes in patients. CONCLUSIONS: These results are consistent with a role for the dentate gyrus in the pathophysiology of bipolar disorder and suggest that depressive episodes and elevated oxidative stress might contribute to hippocampal volume decreases. In addition, these findings provide further support for the hypothesis that peripheral lipid peroxidation markers may reflect brain alterations in bipolar disorders.


Bipolar Disorder , Dentate Gyrus , Depression , Lipid Peroxidation/physiology , Adult , Aldehydes/analysis , Biomarkers/analysis , Bipolar Disorder/metabolism , Bipolar Disorder/pathology , Bipolar Disorder/psychology , Cross-Sectional Studies , Dentate Gyrus/diagnostic imaging , Dentate Gyrus/pathology , Depression/diagnosis , Depression/metabolism , Depression/pathology , Female , Humans , Magnetic Resonance Imaging/methods , Male , Organ Size , Oxidative Stress/physiology , Statistics as Topic
8.
Mol Cancer ; 14: 14, 2015 Jan 27.
Article En | MEDLINE | ID: mdl-25623255

BACKGROUND: B cell precursor acute lymphoblastic leukaemia (BCP-ALL) is the most common paediatric cancer. BCP-ALL blasts typically retain wild type p53, and are therefore assumed to rely on indirect measures to suppress transformation-induced p53 activity. We have recently demonstrated that the second messenger cyclic adenosine monophosphate (cAMP) through activation of protein kinase A (PKA) has the ability to inhibit DNA damage-induced p53 accumulation and thereby promote survival of the leukaemic blasts. Development of BCP-ALL in the bone marrow (BM) is supported by resident BM-derived mesenchymal stromal cells (MSCs). MSCs are known to produce prostaglandin E(2) (PGE(2)) which upon binding to its receptors is able to elicit a cAMP response in target cells. We hypothesized that PGE(2) produced by stromal cells in the BM microenvironment could stimulate cAMP production and PKA activation in BCP-ALL cells, thereby suppressing p53 accumulation and promoting survival of the malignant cells. METHODS: Primary BCP-ALL cells isolated from BM aspirates at diagnosis were cocultivated with BM-derived MSCs, and effects on DNA damage-induced p53 accumulation and cell death were monitored by SDS-PAGE/immunoblotting and flow cytometry-based methods, respectively. Effects of intervention of signalling along the PGE(2)-cAMP-PKA axis were assessed by inhibition of PGE(2) production or PKA activity. Statistical significance was tested by Wilcoxon signed-rank test or paired samples t test. RESULTS: We demonstrate that BM-derived MSCs produce PGE(2) and protect primary BCP-ALL cells from p53 accumulation and apoptotic cell death. The MSC-mediated protection of DNA damage-mediated cell death is reversible upon inhibition of PGE(2) synthesis or PKA activity. Furthermore our results indicate differences in the sensitivity to variations in p53 levels between common cytogenetic subgroups of BCP-ALL. CONCLUSIONS: Our findings support our hypothesis that BM-derived PGE(2), through activation of cAMP-PKA signalling in BCP-ALL blasts, can inhibit the tumour suppressive activity of wild type p53, thereby promoting leukaemogenesis and protecting against therapy-induced leukaemic cell death. These novel findings identify the PGE(2)-cAMP-PKA signalling pathway as a possible target for pharmacological intervention with potential relevance for treatment of BCP-ALL.


DNA Damage , Dinoprostone/metabolism , Mesenchymal Stem Cells/metabolism , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/metabolism , Tumor Suppressor Protein p53/metabolism , Cell Death , Cell Line, Tumor , Coculture Techniques , Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors , Cyclic AMP-Dependent Protein Kinases/metabolism , Humans , Models, Biological , Signal Transduction
9.
Tidsskr Nor Laegeforen ; 134(16): 1569-75, 2014 Sep 02.
Article Nor | MEDLINE | ID: mdl-25178233

BACKGROUND: Allogeneic stem cell transplantation (ASCT) has been a treatment option for patients with serious diseases of the blood and haematopoietic organs in Norway since 1985. Such treatment is potentially curative for selected patients who have a relatively short predicted survival with other treatment modalities. This article summarises the experience and results from ASCT at Oslo University Hospital Rikshospitalet. MATERIAL AND METHOD: The study included all of the 734 adult patients who had undergone allogeneic stem cell transplantation at the Department of Haematology, Rikshospitalet, later Oslo University Hospital Rikshospitalet, from November 1985 to October 2012. RESULTS: At the time of analysis, altogether 384 patients were alive, and the five and ten-year survival rates were 54% and 48% respectively. The median follow-up time was six years. A total of 339 patients (46%) had developed acute graft-versus-host disease (GvHD), and 250 (73%) of these had GvHD ≥ grade II. Altogether 280 out of 602 patients who lived ≥ 100 days after the transplantation (46.5%) developed chronic GvHD. The most frequent causes of death included recurrence of the initial disease in 116 patients (33.1 %), multi organ failure after transplantation in 88 patients (25.4%), infections in 54 patients (16%) and GvHD in 33 patients (9.4%). INTERPRETATION: ASCT is a treatment option with a curative potential for patients with serious haematological diseases when other forms of treatment provide few prospects for recovery. The total survival rate in our study is in accordance with international results for the same time period, and the indications have consistently been in line with what is accepted internationally.


Hematopoietic Stem Cell Transplantation , Adolescent , Adult , Aged , Aged, 80 and over , Cause of Death , Female , Follow-Up Studies , Graft vs Host Disease/epidemiology , Hematopoietic Stem Cell Transplantation/adverse effects , Hematopoietic Stem Cell Transplantation/mortality , Hematopoietic Stem Cell Transplantation/statistics & numerical data , Hospitals, University , Humans , Leukemia, Lymphoid/epidemiology , Leukemia, Lymphoid/therapy , Leukemia, Myeloid/epidemiology , Leukemia, Myeloid/therapy , Male , Middle Aged , Norway , Postoperative Complications/epidemiology , Survival Rate , Transplantation, Homologous/adverse effects , Transplantation, Homologous/mortality , Transplantation, Homologous/statistics & numerical data
10.
Cancer Cell ; 25(6): 794-808, 2014 Jun 16.
Article En | MEDLINE | ID: mdl-24835589

Evidence for distinct human cancer stem cells (CSCs) remains contentious and the degree to which different cancer cells contribute to propagating malignancies in patients remains unexplored. In low- to intermediate-risk myelodysplastic syndromes (MDS), we establish the existence of rare multipotent MDS stem cells (MDS-SCs), and their hierarchical relationship to lineage-restricted MDS progenitors. All identified somatically acquired genetic lesions were backtracked to distinct MDS-SCs, establishing their distinct MDS-propagating function in vivo. In isolated del(5q)-MDS, acquisition of del(5q) preceded diverse recurrent driver mutations. Sequential analysis in del(5q)-MDS revealed genetic evolution in MDS-SCs and MDS-progenitors prior to leukemic transformation. These findings provide definitive evidence for rare human MDS-SCs in vivo, with extensive implications for the targeting of the cells required and sufficient for MDS-propagation.


Myelodysplastic Syndromes/genetics , Myelodysplastic Syndromes/pathology , Neoplastic Stem Cells/physiology , Animals , Antigens, CD/biosynthesis , Antigens, CD/immunology , Chromosome Deletion , Chromosomes, Human, Pair 5 , Flow Cytometry , Gene Expression Profiling , Genetic Predisposition to Disease , Heterografts , Humans , Mice , Mice, Inbred NOD , Mutation , Myelodysplastic Syndromes/immunology , Neoplastic Stem Cells/immunology , Neoplastic Stem Cells/pathology , Prognosis
11.
Blood ; 121(10): 1805-13, 2013 Mar 07.
Article En | MEDLINE | ID: mdl-23299313

B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is the most commonly occurring pediatric cancer. Despite its relatively good prognosis, there is a steady search for strategies to improve treatment effects and prevent the undesired side effects on normal cells. In the present paper, we demonstrate a differential effect of cyclic adenosine monophosphate (cAMP) signaling between normal BCPs and BCP-ALL blasts, pointing to a potential therapeutic window allowing for manipulation of cAMP signaling in the treatment of BCP-ALL. By studying primary cells collected from pediatric BCP-ALL patients and healthy controls, we found that cAMP profoundly decreased basal and DNA damage-induced p53 levels and cell death in malignant cells, whereas normal BCP counterparts displayed slightly augmented cell death when exposed to cAMP-increasing agents. We did not find evidence for a selection process involving generation of increased basal cAMP levels in BCP-ALL cells, but we demonstrate that paracrine signaling involving prostaglandin E2-induced cAMP generation has the potential to suppress p53 activation and cell death induction. The selective inhibitory effect of cAMP signaling on DNA damage-induced cell death in BCP-ALL cells appears to be an acquired trait associated with malignant transformation, potentially allowing the use of inhibitors of this pathway for directed killing of the malignant blasts.


Apoptosis , Blast Crisis/pathology , Cyclic AMP/metabolism , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/pathology , Precursor Cells, B-Lymphoid/cytology , Tumor Suppressor Protein p53/metabolism , Adolescent , Adult , Blast Crisis/drug therapy , Blast Crisis/metabolism , Case-Control Studies , Cells, Cultured , Child , Child, Preschool , Colforsin/pharmacology , DNA Damage/physiology , DNA Damage/radiation effects , Dinoprostone/pharmacology , Female , Humans , Infant , Male , Oxytocics/pharmacology , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/metabolism , Precursor Cells, B-Lymphoid/metabolism , Tumor Suppressor Protein p53/genetics , Young Adult
12.
J Affect Disord ; 135(1-3): 43-50, 2011 Dec.
Article En | MEDLINE | ID: mdl-21880373

BACKGROUND: It has recently been hypothesized that bipolar disorders are associated with accelerated aging. Telomere dysfunction, a biomarker of aging, is determined by the load of short telomeres, rather than by the mean telomere length. To our knowledge, the load of short telomeres has not been reported in any psychiatric disorder. The aims of the study were to examine the load of short telomeres and the mean telomere length and their relationships with illness duration and lifetime number of depressive episodes in bipolar II disorder (BD-II). METHODS: Twenty-eight patients (mean age=34.8 ± 7.7) with a DSM-IV diagnosis of BD-II and 28 healthy control subjects (mean age=34.8 ± 9.2) matched for age, sex, and education participated. The load of short telomeres (percentage of telomeres <3 kilobases) and mean telomere length in peripheral blood mononuclear cells were measured using high-throughput quantitative fluorescence in situ hybridization. RESULTS: The load of short telomeres was significantly increased in patients with BD-II relative to healthy controls and may represent 13 years of accelerated aging. The load of short telomeres and the mean telomere length were associated with lifetime number of depressive episodes, but not with illness duration. LIMITATIONS: Modest sample size and cross-sectional design. CONCLUSIONS: Our results suggest that BD-II is associated with an increased load of short telomeres. Depressive episode-related stress may accelerate telomere shortening and aging. However, longitudinal studies are needed to fully clarify telomere shortening and its relationship with clinical variables in BD-II.


Bipolar Disorder/genetics , Depression/genetics , Telomere Shortening , Adult , Aging/genetics , Bipolar Disorder/psychology , Case-Control Studies , Cross-Sectional Studies , Depression/psychology , Depressive Disorder/genetics , Diagnostic and Statistical Manual of Mental Disorders , Female , Humans , In Situ Hybridization, Fluorescence , Leukocytes, Mononuclear , Longitudinal Studies , Male , Mental Disorders/genetics , Telomere , Time Factors
13.
Eur J Haematol ; 87(6): 494-502, 2011 Dec.
Article En | MEDLINE | ID: mdl-21752097

OBJECTIVE: A Hoechst 33342 dye efflux assay can be used to define a population of immature hematopoietic progenitor cells (HPC) that are called side population (SP) cells. Previously, SP cells examined from bone marrow (BM) and peripheral blood progenitor cells (PBPC) were found to be predominantly CD34 negative. METHODS AND RESULTS: In this study, we show that the level of CD34+ cells within the SP fraction increases from 2% in BM to 15% in mobilized PBPC. Furthermore, SP cells are found in highly enriched CD34+ cells from both BM and PBPC, and these cells define an immature phenotype of HPC. We also observed a higher level of CD133+ cells within the SPCD34+ cell population. Moreover, the frequency of long-term culture-initiating cells (LTC-IC) was markedly increased in SPCD34+ cells. To further investigate whether variations in the level of SP cells in the CD34+ cell fraction influenced short-term engraftment, we studied 20 patients with Hodgkin lymphoma that were autotransplanted with highly enriched CD34+ cells from PB. The percentage of SP cells in the PBCD34+ cell fraction was highly variable, ranging from 0.3 to 22%. No correlation was found between the content of SP cells in the autotransplanted CD34+ cells and time to short-term engraftment. CONCLUSION: SPCD34+ cells in PBPC define an immature phenotype of HPC with increased numbers of LTC-IC, and they are more frequently found in PBPC than in BM. The number of SP cells does not predict time to engraftment.


Antigens, CD34/immunology , Hematopoietic Stem Cell Transplantation , Hematopoietic Stem Cells/cytology , Dose-Response Relationship, Drug , Flow Cytometry , Hematopoietic Stem Cells/immunology , Humans , Treatment Outcome
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