The optimal use of mitoxantrone (NOV) in the high-dose range requires elucidation of its maximum tolerated dose with peripheral blood progenitor cell (PBPC) support and the time interval needed between drug administration and PBPC reinfusion in order to avoid graft toxicity. The aims of this study were: (1) to verify the feasibility and haematological toxicity of escalating NOV up to 90 mg m(-2) with PBPC support; and (2) to verify the safeness of a short (96 h) interval between NOV administration and PBPC reinfusion. Three cohorts of ten patients with breast cancer (BC) or non-Hodgkin's lymphoma (NHL) received escalating doses of NOV, 60, 75 and 90 mg m(-2) plus melphalan (L-PAM), 140-180 mg m(-2), with PBPC rescue 96 h after NOV. Haematological toxicity was evaluated daily (WHO criteria). NOV plasma pharmacokinetics was also evaluated, as well as NOV cytotoxicity against PBPCs. Haematological recovery was rapid and complete at each NOV dose level without statistically significant differences, and there were no major toxicities. NOV plasma concentrations at the time of PBPC reinfusion were below the toxicity threshold against haemopoietic progenitors. It is concluded that, when adequately supported with PBPCs, NOV can be escalated up to 90 mg m(-2) with acceptable haematological toxicity. PBPCs can be safely reinfused as early as 96 h after NOV administration.
Aims—To determine the extent of clonal cell contamination of peripheral blood progenitor cell (PBPC) collections in patients with multiple myeloma (MM) and to assess the purging efficacy of CD34 positive selection.
Methods—PBPC collections from 29 patients with MM were analysed for the presence of clonal immunoglobulin heavy chain (IgH) gene rearrangements with a fluorescence based PCR technique. In addition, the PBPC from eight of the 29 patients were “purged” by selection of CD34 positive haematopoietic progenitors with an avidin-biotin immunoabsorption column (Ceprate). In each case the unmanipulated PBPC, CD34 positive and waste fractions were all assessed for the presence of clonal IgH rearrangements.
Results—Clonal IgH rearrangements (identical with those demonstrated in diagnostic bone marrow samples) were demonstrated in 10 (35%) of 29 cases and seemed to be confined to those with significant residual bone marrow disease. Clonal rearrangements were evident in the PBPC of two of the eight patients who underwent CD34 selection; in both instances a “clonal purge” was seen as it was not possible to demonstrate the clonal rearrangement in the CD34 positive fraction. In four of the six remaining cases the normal polyclonal fingerprint could not be demonstrated in the CD34 positive fraction, which is consistent with a significant reduction in contaminating B cells.
Conclusions—Clonal cells contaminate PBPC collections in a significant proportion of patients with MM and may be eliminated by CD34 positive selection.
PCR; myeloma; CD34
The mini-BEAM regimen (BCNU, etoposide, cytarabine, melphalan) and its modification 'Dexa-BEAM' are effective salvage protocols for relapsed Hodgkin's disease and non-Hodgkin's lymphoma. Since many patients with relapsed lymphoma are eligible for high-dose chemotherapy with autologous stem cell rescue, we were interested in the suitability of these second line regimens for mobilising peripheral blood progenitor cells (PBPC). The kinetics of PBPC were studied in 15 patients treated with Dexa-BEAM and granulocyte colony-stimulating factor (G-CSF). Leukocytes started to rise from < 0.5 nL-1 on day 18 (16-22) after Dexa-BEAM, and exceeded 10 nL-1 on day 20 (18-28). Peripheral blood CFU-GM peaked on day 21 (19-28) and declined slowly thereafter; the median leukocyte count was 18.7 nL-1 (12.2-60) on the day of CFU-GM-peak. The maximum number of CFU-GM circulating in peripheral blood was inversely correlated to the duration of leukopenia after Dexa-BEAM. Measurement of CD34+ cells with the monoclonal antibody 8G12-PE (HPCA-2) predicted the number of CFU-GM precisely in both peripheral blood and leukapheresis products (r = 0.90-0.95). Two to six leukapheresis procedures yielded 6.39 x 10(8) mononuclear cells kg-1 (1.82-13.49) containing 44.4 x 10(4) CFU-GM kg-1 (2.2-213.8). Immunophenotypical analysis revealed that the percentage of CD19+ B cells was very low in all collection products (less than 1%). Nine patients were autografted with PBPC (15.4-213.8 x 10(4) CFU-GM kg-1) after myeloablative chemotherapy and experienced rapid and sustained engraftment (Platelets > 50 nL-1 on day +13 [9-22]). We conclude that PBPC can be mobilised effectively by Dexa-BEAM plus G-CSF. An adequate timing of PBPC collection (when the leukocyte count has exceeded 10 nL-1) and evaluation of the progenitor content of the leukapheresis products with 8G12-PE will allow to minimise the number of leukaphereses.
In order to evaluate the potential clinical and economic benefits of granulocyte colony-stimulating factor (G-CSF, filgrastim) following peripheral blood progenitor cells (PBPC) rescue after high-dose chemotherapy (HDCT), 23 consecutive patients aged less than 60 years with poor-prognosis, high-grade non-Hodgkin's lymphoma (NHL) were entered into a prospective randomized trial between May 1993 and September 1995. Patients were randomized to receive either PBPC alone (n = 12) or PBPC+G-CSF (n = 11) after HDCT with busulphan and cyclophosphamide. G-CSF (300 microg day[-1]) was given from day +5 until recovery of granulocyte count to greater than 1.0 x 10(9) l(-1) for 2 consecutive days. The mean time to achieve a granulocyte count > 0.5 x 10(9) l(-1) was significantly shorter in the G-CSF arm (9.7 vs 13.2 days; P<0.0001) as was the median duration of hospital stay (12 vs 15 days; P = 0.001). In addition the recovery periods (range 9-12 vs 11-17 days to achieve a count of 1.0 x 10(9) l[-1]) and hospital stays (range 11-14 vs 13-22 days) were significantly less variable in patients receiving G-CSF in whom the values clustered around the median. There were no statistically significant differences between the study arms in terms of days of fever, documented episodes of bacteraemia, antimicrobial drug usage and platelet/red cell transfusion requirements. Taking into account the costs of total occupied-bed days, drugs, growth factor usage and haematological support, the mean expenditure per inpatient stay was pound sterling 6500 (range pound sterling 5465-pound sterling 8101) in the G-CSF group compared with pound sterling 8316 (range pound sterling 5953-pound sterling 15,801) in the group not receiving G-CSF, with an observed mean saving of 1816 per patient (or 22% of the total cost) in the G-CSF group. This study suggests that after HDCT and PBPC rescue, the use of G-CSF leads to more rapid haematological recovery periods and is associated with a more predictable and shorter hospital stay. Furthermore, and despite the additional costs for G-CSF, these clinical benefits are not translated into increased health care expenditure.
It is often a clinical dilemma to determine when to collect autologous peripheral blood progenitor cells (PBPCs) in patients who received prior chemotherapy. It is also challenging to predict if the collected cells will be enough for one or two transplants.
STUDY DESIGN AND METHODS
A total of 103 PBPC donors were followed to evaluate factors that predict poor autologous PBPC collection. The donors were categorized into three groups: plasma cell disorders (PCDs), lymphomas, and normal allogeneic donors.
Our evaluation showed that platelet (PLT) count before growth factor administration significantly correlated with total CD34+ cell yield (Spearman r = 0.38, p < 0.001). Further analysis showed this correlation was only significant in plasma cell disease patients who received prior chemotherapy (Spearman r = 0.5, p = 0.008). Baseline PLT counts did not correlate with PBPC collection yield in untreated PCD, lymphoma, and normal allogeneic donors. In addition, daily PLT count during PBPC harvest correlated with CD34+ cell yield for that day (Spearman r = 0.41, p < 0.001). With a multiple linear regression model (adjusted R2 = 0.31, AIC = 63.1), it has been determined that the baseline PLT count significantly correlates with total CD34+ cell yield in treated PCD patients.
Baseline PLT count is a sensitive indicator of autologous PBPC mobilization in PCD patients who received prior chemotherapy. This finding may be considered before growth factor administration to determine the optimal period to mobilize treated PCD patients and to predict if enough cells can be collected for one or two transplants.
Bone marrow (BM) Th1 populations can contribute to graft-versus-leukemia (GvL) responses. G/GM-CSF-mobilized peripheral blood progenitor cells (PBPC) have become widely accepted alternatives to BM transplantation (BMT). T cells co-expressing NK proteins (NKT) include a CD1d-reactive subset which influence immunity by rapidly producing large amounts of Th1 and/or Th2 cytokines dependent upon microenvironment and disease. There are two types of CD1d-reactive NKT. “iNKT” express a semi-invariant TCR-α. Other “non-invariant” CD1d-reactive NKT from BM and liver produce large amounts of IL-4 or IFN-γ respectively, and within the intestine can be biased in either direction. Recent data suggests that NKT might contribute to clinical benefits of PBPC.
To address these issues, we phenotypically and functionally studied PBPC NKT.
Similarly to BM, NKT-like cells were common in allogeneic and autologous PBPC, there were relatively few classical iNKT, but high CD1d-reactivity concentrated in NKT fractions. Significantly, PBPC CD1d-reactive cells were relatively Th1-biased and their presence was associated with better prognosis. G-CSF treatment of BM to yield PBPC in vivo as well as in vitro Th2-polarizes conventional T cells and iNKT. However, G-CSF treatment of BM in vitro produced Th1-biased NKT, providing a mechanism for opposite polarization of NKT from BM versus PBPC.
These results suggest distinct Th1 CD1d-reactive NKT cells could stimulate anti-tumor responses from those previously described, which can suppress GvHD.
To test the hypothesis that the outcome of hematopoietic stem cell grafts is at least partially determined by the cellular composition of the graft, the National Marrow Donor Program analyzed the correlation of cellular phenotypes of unrelated grafts with graft outcome. Samples from 94 bone marrow (BM) and 181 peripheral blood progenitor cell (PBPC) grafts for transplantations at 40 U.S. transplant centers between 2003 and 2005 were analyzed at a single immunophenotyping reference laboratory. Samples were shipped from transplant centers upon receipt of graft. Graft cellular composition included analysis of leukocyte total cell numbers, and subsets of myeloid [CD34+, CD34+ CD38−], lymphoid [CD3+, CD3+ CD4+, CD3+ CD8+], and activated lymphoid cells [CD3+ CD25+, CD3+ CD69+, CD3+ HLA-DR+] coexpressing CD3+. There was substantial variability in the cellular composition of BM and PBPC grafts before and after graft processing by red blood cell (RBC) removal or plasma depletion in preparation for transplant. With BM grafts, cellular composition was not associated with hematopoietic recovery, graft-versus-host disease (GVHD), or survival. With PBPC grafts, survival rates were higher with CD34 + >5 × 106/kg, 59% compared to 34% with CD34+ ≤5 × 106/kg at 1-year. Platelet recovery was higher with PBPC containing CD3+ CD8+ >8 × 107/kg. Neutrophil recovery or GVHD could not be predicted by any cellular subsets of PBPC grafts. Though survival was superior with PBPC grafts containing >5 × 106 CD34+/ kg an optimal graft mix of myeloid, lymphoid and activated lymphoid subsets was not identified.
Graft composition; unrelated donor transplant; hematopoietic recovery; overall survival
B-cell chronic lymphocytic leukaemia (CLL) cannot be cured by conventional therapy. To improve the prognosis of patients with CLL, we have designed a sequential treatment strategy that comprises intensive chemotherapy for mobilization of peripheral blood progenitor cells (PBPCs) and induction of minimal disease, followed by high-dose radiochemotherapy with stem cell reinfusion and post-transplant molecular monitoring by polymerase chain reaction (PCR) amplification of the complementary determining region III (CDRIII) gene. In a prospective study, we have evaluated this protocol in 18 patients with CLL, also including early stages of the disease. The median age was 49 (29-61) years; Binet stages were A, six; B, nine; and C, three. Adverse prognostic factors [high lymphocyte count and/or diffuse bone marrow (BM) infiltration] were present in 16 out of 18 patients. All patients showed a clone-specific molecular marker as demonstrated by PCR amplification of CDRIII rearrangements. For stem cell mobilization and reduction of tumour load, one to two cycles of Dexa-BEAM chemotherapy were administered, resulting in minimal disease (circulating lymphoma cells <1 x 10(9) l(-1); BM infiltration <20%; lymphomas <2 cm) in 16 out of 18 patients, including four patients who already had minimal disease before Dexa-BEAM. Stem cell harvesting was successful in 14 patients. All grafts [three BM, 11 peripheral blood (PB)] were purged from leukaemic cells using immunomagnetic methods. Thirteen patients having achieved minimal disease were reinfused with purged autologous stem cells (ASC) after preparation with total body irradiation and cyclophosphamide. Engraftment was delayed in patients receiving BM (n = 3) but prompt [neutrophils >0.5 x 10(9) l(-1) after 10 (9-13) days, platelets >20 x 10(9) l(-1) after 11 (9-214) days] in patients restored with PBPCs (n = 10). Procedure-related deaths did not occur. Although the results of CDRIII PCR suggest persistence or recurrence of the leukaemic clone in at least three cases, to date only one patient has relapsed, whereas all others survive without clinical evidence of disease with a maximum follow-up of 48 months. We conclude that sequential high-dose therapy using Dexa-BEAM and autologous stem cell transplantation is a safe and highly effective treatment for patients with CLL. However, a longer follow-up is needed to assess whether definite cures can be achieved using this strategy.
Umbilical cord blood (UCB) is increasingly considered as an alternative to peripheral blood progenitor cells (PBPC) or bone marrow (BM), especially when a HLA-matched adult unrelated donor is not available.
In order to establish the appropriateness of current graft selection practices, we retrospectively compared leukemia-free survival and other outcomes for each graft source in patients aged >16 years transplanted for acute leukemia using Cox regression. Data were available on 1525 patients transplanted between 2002 and 2006 using UCB (n=165), PBPC (n=888) and BM (n=472). UCB units were matched at HLA-A and B at antigen level and DRB1 at allele level (n=10) or mismatched at one (n=40) or two antigens (n=115). PBPC and BM grafts from unrelated adult donors were matched for allele-level HLA-A, B, C and DRB1 (n=632; n=332) or mismatched at one locus (n=256; n=140).
Leukemia-free survival after UCB transplantation was comparable to that observed after 8/8 and 7/8 allele-matched PBPC or BM transplantation. Transplant-related mortality, however, was higher after UCB transplantation compared to 8/8 allele-matched PBPC (HR 1.62, p<0.01) or BM (HR 1.69, p<0.01). Grades 2–4 acute and chronic graft-versus-host disease were lower in UCB recipients compared to allele-matched PBPC (HR 0.57, p<0.01 and HR 0.38, p<0.01, respectively), while chronic and not acute graft-versus-host disease was lower after UCB compared to allele-matched BM transplantation (HR 0.63, p=0.01).
Together, these data support the use of UCB for adults with acute leukemia when an HLA-matched unrelated adult donor is lacking and when transplant is urgently needed.
Excessive collection of platelets is an unwanted side effect in current centrifugation-based peripheral blood progenitor cell (PBPC) apheresis. We investigated a novel microchip-based acoustophoresis technique, utilizing ultrasonic standing wave forces for the removal of platelets from PBPC products. By applying an acoustic standing wave field onto a continuously flowing cell suspension in a micro channel, cells can be separated from the surrounding media depending on their physical properties.
Study Design and Methods
PBPC samples were obtained from patients (n = 15) and healthy donors (n = 6) and sorted on an acoustophoresis-chip. The acoustic force was set to separate leukocytes from platelets into a target fraction and a waste fraction, respectively. The PBPC samples, the target and the waste fractions were analysed for cell recovery, purity and functionality.
The median separation efficiency of leukocytes to the target fraction was 98% whereas platelets were effectively depleted by 89%. PBPC samples and corresponding target fractions were similar in the percentage of CD34+ hematopoetic progenitor/stem cells as well as leukocyte/lymphocyte subset distributions. Median viability was 98%, 98% and 97% in the PBPC samples, the target and the waste fractions, respectively. Results from hematopoietic progenitor cell assays indicated a preserved colony-forming ability post-sorting. Evaluation of platelet activation by P-selectin (CD62P) expression revealed a significant increase of CD62P+ platelets in the target (19%) and waste fractions (20%), respectively, compared to the PBPC input samples (9%). However, activation was lower when compared to stored blood bank platelet concentrates (48%).
Acoustophoresis can be utilized to efficiently deplete PBPC samples of platelets, whilst preserving the target stem/progenitor cell and leukocyte cell populations, cell viability and progenitor cell colony-forming ability. Acoustophoresis is, thus, an interesting technology to improve current cell processing methods.
The risk of graft-rejection after allogeneic hematopoietic cell transplantation using conventional cyclophosphamide-based conditioning is increased in patients with bone marrow failure syndromes (BMFS) who are heavily transfused and often HLA-alloimmunized. Fifty-six patients with BMFS underwent fludarabine-based reduced-intensity conditioning and allogeneic peripheral blood progenitor cell (PBPC) transplantation at a single institution. The conditioning regimen consisted of intravenous cyclophosphamide, fludarabine, and equine antithymocyte globulin. Graft-versus-host disease (GVHD) prophylaxis included cyclosporine A alone or in combination with either mycophenolate mofetil or methotrexate. To reduce the risk of graft-rejection/failure, unmanipulated G-CSF mobilized PBPCs obtained from an HLA-identical or single HLA-antigen mismatched relative were transplanted rather than donor bone marrow. Despite a high prevalence of pretransplant HLA-alloimmunization (41%) and a heavy prior transfusion burden, graft-failure did not occur with all patients having sustained donor lympho-hematopoietic engraftment. The cumulative incidence of grade II–IV acute-GVHD and chronic-GVHD was 51.8% and 72%, respectively; with 87.1% surviving at a median follow-up of 4.5 years. A multivariate analysis showed pretransplant alloimmunization and rapid donor T-cell engraftment (≥95% donor by day 30) were both significantly (P < 0.05) associated with the development of chronic-GVHD (adjusted HR 2.13 and 2.99, respectively). These data show fludarabine-based PBPC transplantation overcomes the risk of graft-failure in patients with BMFS, although rapid donor T-cell engraftment associated with this approach appears to increase the risk of chronic-GVHD.
Current treatments for metastatic breast cancer are not associated with significant survival benefits despite response rates of over 50%. High-dose therapy with autologous bone marrow transplantation (ABMT) has been investigated, particularly in North America, and prolonged survival in up to 25% of women has been reported, but with a significant treatment-related mortality. However, in patients with haematological malignancies undergoing autologous transplantation, haematopoietic reconstruction is significantly quicker and mortality lower than with ABMT, when peripheral blood progenitor cells (PBPCs) are used. In 32 women with metastatic breast cancer, we investigated the feasibility of PBPC mobilisation with high-dose cyclophosphamide and granulocyte colony-stimulating factor (G-CSF) after 12 weeks' infusional induction chemotherapy and the subsequent efficacy of the haematopoietic reconstitution after conditioning with melphalan and either etoposide or thiotepa. PBPC mobilisation was successful in 28/32 (88%) patients, and there was a rapid post-transplantation haematopoietic recovery: median time to neutrophils > 0.5 x 10(9) l-1 was 14 days and to platelets > 20 x 10(9) l-1 was 10 days. There was no procedure-related mortality, and the major morbidity was mucositis (WHO grade 3-4) in 18/32 patients (56%). In a patient group of which the majority had very poor prognostic features, the median survival from start of induction chemotherapy was 15 months. Thus, PBPC mobilisation and support of high-dose chemotherapy is feasible after infusional induction chemotherapy for patients with metastatic breast cancer, although the optimum drug combination has not yet been determined.
A homolog of Pseudomonas aeruginosa penicillin-binding protein 3 (PBP3), named PBP3x in this study, was identified by using degenerate primers based on conserved amino acid motifs in the high-molecular-weight PBPs. Analysis of the translated sequence of the pbpC gene encoding this PBP3x revealed that 41 and 48% of its amino acids were identical to those of Escherichia coli and P. aeruginosa PBP3s, respectively. The downstream sequence of pbpC encoded convergently transcribed homologs of the E. coli soxR gene and the Mycobacterium bovis adh gene. The pbpC gene product was expressed from the T7 promoter in E. coli and was exported to the cytoplasmic membrane of E. coli cells and could bind [3H] penicillin. By using a broad-host-range vector, pUCP27, the pbpC gene was expressed in P. aeruginosa PAO4089. [3H]penicillin-binding competition assays indicated that the pbpC gene product had lower affinities for several PBP3-targeted beta-lactam antibiotics than P. aeruginosa PBP3 did, and overexpression of the pbpC gene product had no effect on the susceptibility to the PBP3-targeted antibiotics tested. By gene replacement, a PBP3x-defective interposon mutant (strain HC132) was obtained and confirmed by Southern blot analysis. Inactivation of PBP3x caused no changes in the cell morphology or growth rate of exponentially growing cells, suggesting that pbpC was not required for cell viability under normal laboratory growth conditions. However, the upstream sequence of pbpC contained a potential sigma(s) recognition site, and pbpC gene expression appeared to be growth rate regulated. [3H]penicillin-binding assays indicated that PBP3 was mainly produced during exponential growth whereas PBP3x was produced in the stationary phase of growth.
We compared outcomes of patients with severe aplastic anemia (SAA) who received G-CSF stimulated bone marrow (G-BM) (n=78), unstimulated bone marrow (BM) (n=547), or peripheral blood progenitor cells (PBPC) (n=134) from an HLA-matched sibling. Transplantations occurred in 1997–2003. Rates of neutrophil and platelet recovery were not different among the three treatment groups. Grade 2–4 acute graft-versus-host disease (GVHD) (RR 0.82, p=0.539), grade 3–4 acute GVHD (RR 0.74, p=0.535) and chronic GVHD (RR 1.56, p=0.229) were similar after G-BM and BM transplants. Grade 2–4 acute GVHD (RR 2.37, p=0.012) but not grade 3–4 acute GVHD (RR 1.66, p=0.323) and chronic GVHD (RR 5.09, p<0.001) were higher after PBPC transplants compared to G-BM. Grade 2–4 (RR 2.90, p<0.001), grade 3–4 (RR 2.24, p=0.009) acute GVHD and chronic GVHD (RR 3.26, p<0.001) were higher after PBPC transplants compared to BM. Mortality risks were lower after transplantation of BM compared to G-BM (RR 0.63, p=0.05). These data suggest no advantage to using G-BM and the observed higher rates of acute and chronic GVHD in PBPC recipients warrants cautious use of this graft source for SAA. Taken together, BM is the preferred graft for HLA matched sibling transplants for SAA.
G-mobilized BM; GVHD; aplastic anemia; survival
We evaluated effects of graft transport time on outcomes after transplantation of 938 unrelated donor bone marrow (BM) or 507 peripheral blood progenitor cells (PBPC) in patients with acute or chronic leukemia and myelodysplasia. BM grafts were collected at 107 centers and PBPC, 89 centers. Median time from end of collection to infusion was 14 hours for BM and 15 hours for PBPC. Platelet recovery was less likely in BM recipients when the interval from end of collection to receipt at transplant center was ≥ 20 hours (odds ratio 0.47, p=0.010) and when the interval from receipt to infusion was ≥ 6 hours (odds ratio 0.57, p=0.001). Mortality rates were higher in recipients of HLA-matched BM when the interval from end of collection to receipt at transplant center was ≥ 20 hours (relative risk 2.67, p<0.001) after adjustment for other significant prognostic factors. Mortality after HLA-mismatched BM transplants was not associated with transport time. Transport times had no demonstrable effect on outcomes after PBPC transplants. These data support a general review of current transport procedures, especially for BM grafts requiring longer transport time and every effort made to minimize time from collection to infusion.
transport of unrelated donor grafts; transport times; transplant-outcomes
Immunodeficiency after peripheral blood progenitor cell (PBPC) transplantation may be influenced by graft composition, underlying disease, and/or pre-treatment. These factors are difficult to study independently in humans. Ex vivo culture and genetic manipulation of PBPC grafts may also affect immune reconstitution, with relevance to gene therapy applications. We directly compared the effects of three clinically relevant autologous graft compositions on immune reconstitution after myeloblative total body irradiation in rhesus macaques, the first time these studies have been performed in a large animal model with direct clinical relevance. Animals received CD34+ cell dose-matched grafts of either peripheral blood mononuclear cells, purified CD34+ PBPCs, or purified CD34+ PBPCs expanded in vitro and retrovirally transduced. We evaluated the reconstitution of T, B, natural killer, dendritic cells, and monocytes in blood and lymph nodes for up to 1 year post-transplantation. Animals receiving selected-transduced CD34+ cells had the fastest recovery of T-cell numbers, along with the highest T-cell-receptor gene rearrangement excision circles levels, the fewest proliferating Ki-67+ T-cells in the blood, and the best-preserved thymic architecture. Selected-transduced CD34+ cells may therefore repopulate the thymus more efficiently and promote a higher output of naïve T-cells. These results have implications for the design of gene therapy trials, as well as for the use of expanded PBPCs for improved T-cell immune reconstitution after transplantation.
T-cell immune reconstitution; In vitro expansion; Retroviral gene transfer; Autologous; Transplantation Peripheral blood progenitor cell; Rhesus macaque; Thymus
In this study we demonstrate that the hemopoietic growth factor, G-CSF successfully mobilised progenitor cell populations into the peripheral blood in a population of patients despite intensive pretreatment with chemotherapy. Administration of G-CSF increased the numbers of peripheral blood progenitor cells (PBPC) by a median of 76-fold above basal levels. Maximal levels of PBPC were observed on days 5 and 6 after G-CSF treatment. In two patients a second cycle of G-CSF mobilised PBPC to levels comparable with those seen after the first cycle of G-CSF treatment. An earlier hemopoietic cell population (pre-CFC's) was also mobilised with levels increased up to 50-fold above basal levels. Using a standard mononuclear cell leukapheresis technique the PBPC were collected extremely efficiently (essentially 100%) and could be further successfully enriched by separation using a Ficoll gradient. For patients who underwent the optimal collection protocol (i.e. leukapheresis on days 5, 6 and 7) a total of 32 +/- 6 x 10(4) GM-CFC kg-1 were collected. The ability to mobilise PBPC using G-CSF alone and to successfully and efficiently harvest these cells has important implications for the future of transplantation and high dose chemotherapy procedures.
Background/Aims: Peripheral blood progenitor cell (PBPC) transplantation is frequently used in the treatment of malignant diseases, but contamination of the graft by tumour cells is a real concern and may lead to disease relapse. The feasibility of applying heterogeneous single base genetic changes as tumour specific markers to detect minimal residual disease in PBPC harvests was studied, using the p53 gene and breast cancer as models.
Methods: Tumour tissues from 51 patients with cellular aliquots from PBPC harvests available were studied. Thirty eight patients had metastatic disease or were at high risk of metastasis, and 13 had high risk stage II/III disease with four or more involved axillary lymph nodes. Tumour DNA was screened for p53 mutations in exons 5 to 9, using denaturing gradient gel electrophoresis, followed by sequencing. Based on sequence information, allele specific primers were designed for each mutation and the non-radioisotopic, amplification refractory mutation system (ARMS) was used to screen DNA from PBPC harvests for minimal residual disease. Attempts were made to optimise each system, based on parameters determined using the T47D breast cancer cell line with a confirmed point mutation in codon 194.
Results: Twelve different somatic mutations were found, two of which could not be sequenced. The remainder were point mutations. Only five of the 10 ARMS systems were successfully optimised, and minimal residual disease detection sensitivities ranged from one copy of tumour DNA in 102 to 103 copies of wild-type DNA. Using ARMS, three of five patients and eight of 12 of their PBPC harvests showed minimal residual disease.
Conclusions: These results suggest that the use of single base genetic changes in minimal residual disease detection is relatively insensitive and is limited to a small number of patients and to certain mutations. In addition, it is labourious and therefore unlikely to play an important role in clinical practice.
amplification refractory mutation system; progenitor cells; tumour contamination
Non-Hodgkin lymphoma (NHL) can involve the paratesticular organs as the primary disease, as primary testicular lymphoma that secondarily involves the paratesticular structures, as the initial site of presentation of occult nodal disease or as the result of disease dissemination. Primary follicular lymphoma of the epididymis in an adult is extremely rare. Little is known about primary adult paratesticular/epididimal lymphomas.
We report a rare case of primary follicular non-Hodgkin lymphoma of the epididymis in a 90-year-old Caucasian man who presented with a left scrotal mass. Bone marrow biopsy was negative and computed tomography of the total body revealed no evidence of extratesticular involvement. Macroscopically, the epididymis was replaced completely by a uniform mass. Histologic studies revealed a dense lymphoid infiltrate predominantly composed of centrocytes with admixed centroblasts. Immunohistochemical analyses demonstrated that neoplastic cells strongly expressed CD45RB, CD20, CD79a, bcl-6 and CD10; bcl-2 immunostaining was negative. Molecular studies showed the presence of the monoclonal IgH gene rearrangement and the IgH/BCL2 rearrangement. The lymphoma was classified as follicular lymphoma, low grade, grade 1-2. The patient subsequently underwent radical orchiectomy, did not receive chemotherapy and post-operative follow-up showed absence of disease recurrence.
The case of primary follicular lymphoma of epididymis, reported here, is considered a very rare event. It is characterized by clinically indolent localized disease, a good clinical outcome, lack of expression of BCL2 protein and the presence of the t(14;18)(q32;q21)/IGH-BCL2. Even if it is a single case, the primary follicular lymphoma epididymis with t(14;18) could represent either a variant of the previously reported t(14;18)-negative primary paratesticular follicular lymphoma or a distinct biological entity. To report additional cases in the future would be helpful in resolving this question.
Dose intensity may be an important determinant of the outcome in cancer chemotherapy, but is often limited by cumulative haematological toxicity. The availability of haematopoietic growth factors such as granulocyte colony-stimulating factor (G-CSF) and of peripheral blood progenitor cell (PBPC) transplantation has allowed the development of a new treatment strategy in which several courses of high-dose combination chemotherapy are administered for the treatment of solid tumours. PBPCs were mobilised before chemotherapy using 12 or 30 micrograms kg-1 day-1 G-CSF (Filgrastim) for 10 days, and were collected by 2-5 leucaphereses. The yields of mononuclear cells, colony-forming units and CD34-positive cells were similar at the two dose levels of Filgrastim, and the numbers of PBPCs were sufficient for rescue following multiple cycles of chemotherapy. High-dose chemotherapy (cyclophosphamide 2.5 g m-2 for 2 days, etoposide 300 mg m-2 for 3 days and cisplatin 50 mg m-2 for 3 days) was administered sequentially for a median of three cycles (range 1-4) to ten patients. Following the 30 evaluable cycles, the median duration of leucopenia < or = 0.5 x 10(9) l-1 and < or = 1.0 x 10(9) l-1 was 7 and 8 days respectively. The median time of thrombopenia < or = 20 x 10(9) l-1 was 6 days. There was no cumulative haematological toxicity. The duration of leucopenia, but not of thrombopenia, was inversely related to the number of reinfused CFU-GM (granulocyte-macrophage colony-forming units). In the majority of patients, neurotoxicity and ototoxicity became dose limiting after three cycles of therapy. However, the average dose intensity delivered was about three times higher than in a standard regimen. The complete response rate in patients with small-cell lung cancers was 66% (95% CI 30-92%) and the median progression-free survival and overall survival were 13 months and 17 months respectively. These results are encouraging and should be compared, in a randomised fashion, with standard dose chemotherapy.
Although enumeration of CD34+ cells in the peripheral blood (PB) on the day of apheresis predicts the quantity of those cells collected, the flow cytometric techniques used are complex and expensive, and several hours are required to obtain the result in the clinical practice setting. The Sysmex SE-9000 automated haematology analyzer provides an estimate of immature cells, called hematopoietic progenitor cells (HPC). The aim of this study was to evaluate the clinical usefulness of HPC in predicting the optimal timing of peripheral blood progenitor cells (PBPC) harvest. Studies were performed on 628 aphereses from 160 patients with hematologic or solid malignancies. Spearman's rank statistics was used to assess correlation between HPC, WBC, mononuclear cells (MNC), and CD34+ cells. A receiver operating characteristic (ROC) curve was drawn for cutoff value of HPC, and predictive values of the chosen cutoff value of HPC for different target CD34+ cell collections were calculated. The PB HPC had a stronger correlation (rho=0.592, p<0.001) with collected CD34+ cells than did PB WBC and PB MNC. The ROC curve showed that the best cutoff value of HPC was 50 x 10(6)/L for the target CD34+ cells > or =1 x 10(6)/kg with sensitivity of 75%. Positive and negative predictive values of HPC > or =50 x 10(6)/L for CD34+ cells > or =1 x 10(6)/kg were 59.7% and 81.1%, respectively. In the clinical practice setting, applying variable cutoff values of HPC would be a useful tool to predict the optimal timing of PBPC collection.
The purpose of the present study was to investigate the impact of the use of peripheral blood progenitor cells (PBPCs) on the induction of autologous graft-versus-host disease (GVHD) in patients with advanced breast cancer. 14 women with stage IIIB and 36 women with stage IV breast cancer received cyclosporine (CsA) 2.5 mg kg–1 i.v. daily, d 0–28, and interferon-gamma (IFNg) 0.025 mg/m2 s.c. qod, d7–28, following PBPC-T ± bone marrow transplantation (BMT). Preceding high-dose chemotherapy consisted of cyclophosphamide 6 g/m2 and thiotepa 800 mg/m2. Histologically proven ≥grade II cutaneous GVHD was induced in18/50 (36%) of patients and was independent of the source of haematopoietic support. In vitro studies showed that post-transplant, 76% of patients had developed auto-cytotoxicity against their own pre-transplant PHA-lymphoblasts. A significant correlation between the occurrence of GVHD ≥grade II and cytolysis was observed in the NK cell-line K562 and the T47D breast cancer cell-line. With a median follow-up of 2½ years, the overall survival (OS) is 58%, the disease-free survival (DFS) 26%, both independent of the development of GVHD and similar to what has been observed in other studies on high-dose chemotherapy in advanced breast cancer. It therefore remains unclear whether the induction of autologous GVHD with the occurrence of auto-cytotoxic lymphocytes can result in an anti-tumour effect in this group of patients. © 2000 Cancer Research Campaign http://www.bjcancer.com
breast cancer; autoreactive T-cells; cyclosporine; CLIP; MHC-class II; peripheral stem cells
Reduced intensity conditioning (RIC) regimens have been used extensively in adults with hematological malignancies. To address whether this is a feasible approach for children with acute lymphoblastic leukemia (ALL), we evaluated transplant outcomes in 38 recipients transplanted from 1995–2005 for whom this was their first transplant. The median age at transplant was 12 years and 47% had performance scores <90%. Disease status was first complete remission (CR) in 13%, ≥CR2 in 60% of patients and 22% had active disease at transplantation. Matched related donors were available for a third of patients and about half of whom received bone marrow (BM) and the others, peripheral blood progenitor cells (PBPC). Sixty percent of unrelated donor transplant recipients received PBPC. The day-100 probability of grade 2–4 acute GVHD was 37% and the 3-year probability of chronic GVHD, 26%. At 3-years, the probability of transplant related mortality was 40%, relapse, 37% and disease-free survival (DFS), 30%. These data indicate long-term DFS can be achieved using RIC regimens in children with ALL. Given the relatively small cohort, these findings must be validated in a larger population.
pediatric; ALL; reduced intensity conditioning
Children/adolescents with mature B-cell non-Hodgkin lymphoma (B-NHL) have an excellent prognosis but relapses still occur. While chromosomal aberrations and/or clonal immunoglobulin (Ig) gene rearrangements may indicate risk of failure, a more universal approach was developed to detect minimal disease (MD). Children/adolescents with intermediate-risk B-NHL were treated with French-British-American/Lymphome Malins de Burkitt 96 (FAB/LMB96) B4 modified chemotherapy and rituximab. Specimens from diagnosis, end of induction (EOI), and end of therapy (EOT) were assayed for MD. Initial specimens were screened for IGHV family usage with primer pools followed by individual primers to identify MD. Thirty-two diagnostic/staging specimens screened positive with primer pools and unique IGHV family primers were identified. Two patients relapsed; first relapse (4 months from diagnosis) was MD-positive at EOI, the second (36 months from diagnosis) was MD-positive at EOT. At EOI, recurrent rates were similar between the MRD-positive and MRD-negative patients (p=0.40). At EOT, only 13/32 patients had MRD data available with 1 relapse in the MRD-positive group and no recurrences in the MRD-negative group (p=0.077). The study demonstrated molecular-disseminated disease in which IgIGHV primer pools could be used to assess MD. This feasibility study supports future investigations to assess the validity and significance of MD screening in a larger cohort of patients with intermediate-risk mature B-NHL.
non-Hodgkin lymphoma; minimal residual disease; lymphoma; polymerase chain reaction; immunoglobulin rearrangement
Whereas ex vivo expanded megakaryocytic progenitor cells have been investigated for their ability to support platelet regeneration, the question whether more mature platelet-like particles expanded from hematopoietic progenitor cells may be useful for transfusion purposes remains largely elusive.
Human peripheral blood progenitor cells (PBPCs) were enriched using surface expression of CD34 by immunoselection. CD34+ enriched PBPCs were expanded ex vivo in serum-free medium supplemented with cytokines. As a proof-of-principle, distribution of expanded CD61+ particles was analyzed after transfusion into Non-Obese Diabetic/ Severe Combined Immunodeficiency (NOD/SCID) mice.
Highest ex vivo expansion for CD41+/CD61 + cells was achieved when medium was supplemented with SCF, TPO and IL-3. During expansion culture, CD34 marker expression decreased from 85 to 2–8%, while megakaryocytic cells appeared and CD41 and CD61 expression increased from 3 to about 30%. After transfusion of the expanded cells in NOD/SCID mice, CD61 + cells located mainly to bone marrow and to a lesser degree to spleen, but also circulated in blood.
Platelet-like particles using cytokine-substituted serumfree medium can be generated efficiently from CD34+ expansion cultures, but mainly home to hematopoietic tissue.
CD34; CD41; CD61; HSC; Megakaryocytic precursor cells; Platelets