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Y Takaue

Publications and source records attributed to Y Takaue.

At least 73 records · Page 4Linked to original sources
PubMed1999

Comparative evaluation of procedures with a Baxter CS-3000 cell separator for collecting peripheral blood cells from children.

The safety and efficacy of apheresis using a newly developed procedure with a small volume separation container holder (SVSCH, Baxter) for the collection of PBSC from children with cancer were retrospectively compared with our historical experience with other procedures using different equipment and the CS-3000 plus cell separator. The procedures tested included the application of (a) specialized collection protocol 4 using the combination of an SVSCH and a small volume collection chamber (SVCC) (group A: 6 collections in 4 patients), (b) standard lymphocyte collection protocol 3 with GRANULO separation (G) and A-35 collection chambers (group B: 9 collections in 5 patients), and (c) modified collection procedure 1-120 with G and SVCC (group C: 7 collections in 3 patients). Although the retrospective nature of this study and the differences in the cohorts tested prevent a reliable analysis, the percent decrease in the peripheral platelet count after collection tended to be minimum in group A (11% +/- 5% versus 23% +/- 4% [B] or 17% +/- 4% [C]). Moreover, the largest number of CD34+ cells was collected in group A (8.7 +/- 9.4 x 10(5)/100 ml processed blood) compared with groups B (5.5 +/- 7.5 x 10(5)/100 ml processed blood) and C (4.0 +/- 2.8 x 10(5)/100 ml processed blood). These data suggest that a procedure incorporating SVSCH can be safely and effectively applied to small children and enables the selective collection of PBSC with less contamination by platelets, which is useful for subsequent cell processing.

Adolescent↗
PubMed1999

Autologous and allogeneic transplantation with peripheral blood CD34+ cells: a pediatric experience.

BACKGROUND AND OBJECTIVE: Peripheral blood stem cells (PBSC) have replaced bone marrow (BM) as the primary form for autologous hematopoietic stem cell transplantation. Furthermore, the use of allogeneic PBSC transplantation is now rapidly expanding and several centers have adopted this procedure. A new strategy in the use of PBSC is positive selection of CD34+ hematopoietic progenitor (CD34+) cells, and indeed large-scale devices for the clinical exploitation of CD34+ cell selection are now commercially available. In the autologous setting, the primary advantage of using CD34+ selected PBSC is reduced tumor cell contamination during PBSC preparation. On the other hand, in the allogeneic setting, CD34+ selection methods are used to reduce the incidence and severity of GvHD. Initial trials of CD34+ selected PBSC transplants have mainly been performed in adult cancer patients, and experience with CD34+ selected PBSC transplantation in pediatric populations is still limited. The purpose of this review is to clarify the status of CD34+ selected PBSC transplantation in the pediatric population. EVIDENCE AND INFORMATION SOURCES: All authors of the present review work in the field of pediatric stem cell transplantation and in a stem cell processing laboratory, and have contributed to original papers published in peer-reviewed journals. The materials examined in the present review include articles and abstracts published in journals covered by the Science Citation Index and Medline. However, since there is still limited experience with CD34+ cell selection in pediatric populations, information on experience in adults will be discussed regarding the CD34+ cell-selection procedures and transplantation. Pediatric experience with transplants with CD34+ selected cells will be presented and discussed primarily based on our own experience. Specific problems related to PBSC mobilization and collection in children will also be discussed. STATE OF THE ART: A review of the literature shows that with current CD34+ selection methods, purity of the CD34+ cell fraction can range from 30% to 90%, and two to three logs of T-cell depletion can be achieved. Tumor cell contamination has not yet been fully evaluated. The clonogenic activity of progenitor cells after CD34+ selection from PB remains high. Transplantation of autologous selected CD34+ cells from PBSC gives prompt and stable engraftment. The long-term therapeutic efficacy should be evaluated with regard to tumor recurrence. Allogeneic CD34+ selected cells successfully engraft immunomyeloablated recipients though a mega-cell dose effect between HLA-matched pairs. The results of allogeneic CD34+ selected cell transplantation from HLA-mismatched donors are, so far, not satisfactory because of the high rate of rejection, severe infectious complications and relapse of the disease. CD34+ selection may also be used as a target of gene therapy, as a source of dendritic cells for cancer immunotherapy and for the treatment of patients with autoimmune disease.

Antigens, CD34↗
PubMed1999

[Hematopoietic stem cell transplantation in childhood leukemias].

With the recent remarkable progress in cell processing technology, the number of patients or types of disease that are treated with hematopoietic stem cell transplantation (HSCT) has been rapidly increasing in both autologous or allogeneic settings. Transplantable cells can be harvested from blood or the umbilical cord as well as from bone marrow, and CD34+ cells can be effectively isolated as a pure stem cell source. However, the clinical benefit of HSCT in the treatment of hematological malignancies has remained unclear. As HSCT is principally a measure of stem cell rescue after high-dose chemotherapy with or without radiation therapy, it is difficult to clarify its contribution to the cure of the disease. Given these circumstances, pediatric patients with extremely high-risk features like Ph1 ALL or 11q23 translocation are usually selected for allogeneic HSCT even in the 1st CR. Additionally, HSCT could also reasonably be applied to those in 2nd CR or later. These considerations are based upon the idea that transplant-related mortality (TRM) is still too high in allogeneic settings. Allogeneic HSCT may be the first choice for treatment of such patients, if TRM becomes low and it is scientifically proved to be effective. On the other hand, autologous HSC grafts may be contaminated with cancer cells and lack the potency of allogeneic cell-mediated immune function. To improve the clinical results in this setting, a new type of anticancer agent with lower toxicity and a new strategy including immunotherapy should be established.

Antigens, CD34↗
PubMed1999

[Central nervous system relapse with multiple brain masses in an acute promyelocytic leukemia patient treated with all-trans retinoic acid].

A 22-year-old woman with fever and bleeding tendency was given a diagnosis of acute promyelocytic leukemia (APL) on the basis of laboratory findings including a WBC count of 106 x 10(3)/microliter (90% blasts) and a platelet count of 1.6 x 10(4)/microliter. Induction therapy was started with all-trans retinoic acid (ATRA) and cytotoxic chemotherapy. After the patient achieved complete remission, ATRA was discontinued and consolidation chemotherapy was started. However, 4 months after onset, leukemic blasts were detected in cerebrospinal fluid. Temporal central nervous system remission was induced by intrathecal chemotherapy only. However, 2 months later, multiple focal mass lesions had developed in the brain. ATRA (45 mg/m2) was restarted together with multiple intrathecal injections of anticancer drugs, and a third remission was achieved. It is conceivable that the incorporation of ATRA in induction chemotherapy is related to the development of this rather rare complication of APL. The outcome in this case suggested orally administered ATRA may be effective in treating brain metastasis of APL.

Administration, Oral↗
PubMed1998

Marginal benefit/disadvantage of granulocyte colony-stimulating factor therapy after autologous blood stem cell transplantation in children: results of a prospective randomized trial. The Japanese Cooperative Study Group of PBSCT.

In this prospective trial, a total of 74 children who were scheduled to undergo high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation (PBSCT) were prospectively randomized at diagnosis to evaluate the effectiveness of exogenous granulocyte colony-stimulating factor (G-CSF) treatment in accelerating hematopoietic recovery after PBSCT. The diagnosis included acute lymphoblastic leukemia (ALL) (n = 27), neuroblastoma (n = 29), and miscellaneous solid tumors (n = 18). Eligibility criteria included (1) primary PBSCT, (2) chemotherapy-responsive disease, and (3) collected cell number >1 x 10(5) colony-forming unit-granulocyte-macrophage (CFU-GM)/kg and >1 x 10(6) CD34(+) cells/kg patient's body weight. After applying the above criteria, 11 patients were excluded due to disease progression before PBSCT (n = 6) or a low number of harvested cells (n = 5), leaving 63 patients for analysis; 32 patients in the treatment group (300 microg/m2 of G-CSF intravenously over 1 hour from day 1 of PBSCT) and 31 in the control group without treatment. Two distinct disease-oriented high-dose regimens without total body irradiation consisted of the MCVAC regimen using ranimustine (MCNU, 450 mg/m2), cytosine arabinoside (16 g/m2), etoposide (1.6 g/m2), and cyclophosphamide (100 mg/kg) for patients with ALL, and the Hi-MEC regimen using melphalan (180 mg/m2), etoposide (1.6 g/m2), and carboplatinum (1.6 g/m2) for those with solid tumors. Five patients (two in the treatment group and three in the control group) were subsequently removed due to protocol violations. All patients survived PBSCT. The median numbers of transfused mononuclear cells (MNC), CD34(+) cells, and CFU-GM were, respectively, 4.5 (range, 1 to 19) x 10(8)/kg, 8.0 (1.1 to 25) x 10(6)/kg, and 3.7 (1.2 to 23) x 10(5)/kg in the treatment group (n = 30) and 2.9 (0.8 to 21) x 10(8)/kg, 6.3 (1.1 to 34) x 10(6)/kg, and 5.5 (1.3 to 37) x 10(5)/kg, respectively, in the control group (n = 28), with no significant difference. After PBSCT, the time to achieve an absolute neutrophil count (ANC) of >0.5 x 10(9)/L in the treatment group was less than that in the control group (median, 11 v 12 days; the log-rank test, P =.046), although the last day of red blood cell (RBC) transfusion (day 11 v day 10) and the duration of febrile days (>38 degrees C) after PBSCT (4 v 4 days) were identical in both groups. However, platelet recovery to >20 x 10(9)/L was significantly longer in treatment group than control group (26 v 16 days; P =.009) and >50 x 10(9)/L tended to take longer in the treatment group (29 v 26 days; P =.126), with significantly more platelet transfusion-dependent days (27 v 13 days; t-test, P =.037). When patients were divided into two different disease cohorts, ALL patients showed no difference in engraftment kinetics between the G-CSF treatment and control groups, while differences were seen in those with solid tumors. We concluded that the marginal clinical benefit of 1 day earlier recovery of granulocytes could be offset by the delayed recovery of platelets. We recommend that the routine application of costly G-CSF therapy in children undergoing PBSCT should be seriously reconsidered.

Adolescent↗
PubMed1998

Frequent aberration of FHIT gene expression in acute leukemias.

We analyzed the mRNA expression of the FHIT gene by reverse transcription-PCR (RT-PCR) in 54 cases of acute lymphoblastic leukemia (ALL; 11 cases of T-cell ALL [T-ALL] and 43 cases of non-T-ALL) and 40 cases of acute myeloid leukemia (AML). In 46% of the ALL cases and 55% of the AML cases, FHIT expression was absent or markedly decreased. Only abnormal short bands were detected in 30% of the ALL cases and 5% of the AML cases. Eighteen of 19 abnormal transcripts had the same fusion of exons 2-7, and all lacked the starting codon in exon 5. No obvious normal-sized PCR products were detected in cases exhibiting abnormal transcripts. These findings suggest that the expression of functional FHIT protein was lost in the majority of ALL (76%) and AML (60%) cases. Differential quantitative PCR of exons 3-9 of the FHIT gene and RT-PCR of the PTPRG gene, which is centromeric to the FHIT gene, showed the presence of the target sequences. Fluorescence in situ hybridization analysis using probes covering exons 5 and 8 revealed no difference in the signal patterns between leukemia and normal cells, showing one or two signal doublets in more than 90% of nuclei, and indicated that gross segments of the FHIT gene were not homozygously deleted in these cases. A small number of transcripts with an aberrant fusion between exons 2 and 7 were detected by RT-PCR in the bone marrow cells from four healthy individuals. Granulocytes, lymphocytes, and monocytes in the bone marrow cells of a healthy individual contained transcripts with the same fusion. This unique fusion of exons 2 and 7 might be preferentially seen in either neoplastic or normal hematopoietic cells, regardless of their lineage. The finding that FHIT expression was abolished in the majority of leukemia cases might support the hypothesis that the FHIT gene acts as a tumor suppressor, at least in leukemia.

Acid Anhydride Hydrolases↗
PubMed1998

Partially mismatched pediatric transplants with allogeneic CD34(+) blood cells from a related donor.

This was a phase I, multi-center study of 13 pediatric patients (median age, 11 years) to evaluate toxicity, hematopoietic recovery, and graft-versus-host disease (GVHD) after allogeneic transplantation of enriched blood CD34(+) cells obtained from genotypically haploidentical but partially HLA-mismatched related donors (8 parents and 5 siblings). With regard to rejection, donor HLA disparity was 1 (5), 2 (6), or 3 loci (2). With regard to GVHD, recipient HLA disparity was 0 (1), 1 (3), 2 (8), or 3 (1). The patients suffered from acute myelogenous leukemia (6), chronic myelogenous leukemia (4), acute lymphoblastic leukemia (2), or hemolytic anemia plus immunodeficiency disorder (1). To reduce the risk of graft failure through the infusion of a large amount of stem cells, peripheral blood cells (PBC) were mobilized by recombinant granulocyte colony-stimulating factor (G-CSF; lenograstim, 10 microgram/kg/d for 5 days) and collected by 2 to 5 aphereses. To both enhance engraftment and reduce GVHD, CD34(+) cells were enriched using immunomagnetic procedures with the Baxter ISOLEX 300 system (Baxter Healthcare Corp, Irvine, CA) and cryopreserved. After variable cytoreductive regimens, a median of 7.7 (range, 2.2 to 14) x 10(6)/kg of CD34(+) cells and 1.03 (0.05 to 2.09) x 10(5)/kg CD3(+) cells were infused. Using Center-specific posttransplant supportive care and immunosuppressive GVHD prophylaxis, two patients experienced early death; one from veno-occlusive disease at day 17 and one from sepsis at day 18. Nine of 11 patients showed signs of engraftment; however, subsequent rejection was seen in 4 patients, 2 of whom had autologous recovery. Eight patients were evaluated in the early phase of marrow recovery. The median number of days to achieve an absolute granulocyte count of 0.5 x 10(9)/L was 14 (range, 9 to 20) and that to achieve a platelet count of 20 x 10(9)/L was 17.5 (range, 12 to 23). Donor chimerism persisted in five patients until death or current survival. All of the surviving patients with functioning-donor-type hematopoiesis were given total body irradiation. De novo acute GVHD (grades II and IV) was observed in two of the eight evaluated patients. Scheduled donor lymphocyte infusion (DLI), using the CD34(-) fraction, was administered to four patients, free of de novo acute GVHD, beginning between 28 to 43 days after transplant. Three of these patients developed acute GVHD (grades I, II, and IV). Cytomegalovirus infection was a major infectious complication but was successfully managed with gamma-globulin and gancyclovir treatment with or without additional DLI. Five patients are currently surviving, free of disease, with a follow-up ranging from 476 to 937 days. Each survivor has functioning hematopoiesis, three of donor origin and two of autologous origin. In conclusion, our results show that enriched blood CD34(+) cells from a mismatched haploidentical donor are a feasible alternative source of stem cells, but do not appear to ensure engraftment. Because none of the patients who were administered DLI survived, the therapeutic efficacy and safety of periodic DLI, as an integrated part of such transplants, needs to be clarified in further studies.

Adolescent↗
PubMed1998

Mutational analysis of the N-ras gene in acute lymphoblastic leukemia: a study of 125 Japanese pediatric cases.

A point mutation of the N-ras gene is one of the known genetic alterations identified in patients with acute lymphoblastic leukemia (ALL), but its clinical importance is still controversial. Using polymerase chain reactions, we examined codons 12, 13 and 61 of this gene in 125 Japanese childhood ALL patients (64 common-ALL, 22 pre-B-ALL, 33 T-ALL, 2 B-ALL, 3 undifferentiated ALL, and 1 unclassified ALL) including 9 relapsed patients. An N-ras point mutation was observed in 14 (11%) patients (9 common-ALL, 3 T-ALL, and 2 undifferentiated ALL; 13 patients at diagnosis and 1 at relapse). The patients with undifferentiated ALL harbored an N-ras mutation at a significantly higher rate. However, no correlation was found between the presence of an N-ras mutation and sex, age, or white blood count. There was no significant difference in the event-free survival rate between 13 fresh patients with an N-ras mutation and 103 patients with a wild-type configuration. The N-ras mutation was present in about 10% of childhood ALL cases but it did not have a prognostic impact. The sequence analyses revealed that the majority of the patients (13/14) had an N-ras mutation of a G to A transition. This finding was consistent with previous reports on N-ras mutations in acute leukemias in which the incidence of a G to A mutation was significantly higher in ALL than in myeloid malignancies.

Child↗
PubMed1998

New consecutive high-dose chemotherapy modality with fractionated blood stem cell support in the treatment of high-risk pediatric solid tumors: a feasibility study.

For the treatment of childhood solid tumors, we performed a pilot feasibility study of consecutive high-dose therapies, in which each course was followed by transplantation with granulocyte colony-stimulating factor-mobilized peripheral blood cells which had been separated into CD34-positive and -negative fractions by an Isolex system (Baxter). Positive selection of CD34+ cells has been associated with inevitable cell loss. To overcome this loss, CD34+ cells that had migrated into the negative fraction were saved and used for the first transplant, which was followed by a second transplant after a 3- to 5-month interval. In this phase I feasibility study, the results in six children were evaluated for safety and engraftment. Multi-drug cytoreductive regimens using ranimustine (MCNU), melphalan, thiotepa, carboplatin, cyclophosphamide or VP-16 were comparable between the two transplant procedures in terms of their intensity. The number of CD34+ cells in the 'CD34(+) fraction' was 3.31 x 10(6)/kg (0.63-4.3 x 10(6)/kg), while this number in the 'CD34(-) fraction' could not be evaluated correctly due their scarcity (<0.1%). The median numbers of infused MNC and CFU-GM were, respectively, 4.2 x 10(6)/kg and 1.75 x 10(5)/kg in the CD34(+) fraction, and 4.8 x 10(8)/kg and 3.35 x 10(5)/kg in the CD34(-) fraction. The number of days required to achieve an ANC >0.5 x 10(9)/l and a platelet count >20 x 10(9)/l and >50 x 10(9)/l were, respectively, 14.5, 15.0 and 19.5 in the first transplant with CD34- cells, and 13.5, 18.0 and 25.0 in the second transplant with CD34+ cells, with no essential difference between the two treatments. Although the small number of patients, the variation in clinical status and treatment, and the short follow-up invalidate any evaluation of the therapeutic benefit of this strategy, the encouraging results support the feasibility of this strategy, which enables an escalation of dose intensity with an improved cost/benefit ratio.

Adolescent↗
PubMed1998

Peripheral blood stem cell autografts for the treatment of children over 1 year old with stage IV neuroblastoma: a long-term follow-up.

This is the first report of the long-term therapeutic results in 22 children more than 1 year old with stage IV neuroblastoma who were treated with autologous peripheral blood stem cell transplantation (PBSCT). The median age of the patients at PBSCT was 4 years (1 to 10 years) and seven of the 17 patients who were evaluated for N-myc amplification were positive. PBSC were collected by a median of four aphereses per patient. The patients underwent PBSCT from 6 to 21 months after the start of therapy (median 10.5 months) at which time 13 patients were in CR, seven were in PR, and two had refractory disease. Multi-drug therapy using the 'high-MEC' regimen consisting of carboplatinum (400 mg/m2) and VP-16 (200 mg/m2) on days -7 to -4, and melphalan (90 mg/m2) on days -3 and -2, was the primary cytoreductive regimen. The median number of infused MNC and CFU-GM was, respectively, 4.3 x 10(8)/kg and 2.4 x 10(5)/kg. After PBSCT, three patients died of regimen-related toxicities and one patient who was transplanted with refractory disease died of disease progression without any benefit from transplantation. Hematological recovery was evaluated in 21 patients, excluding one early death. The median number of days required to achieve an AGC of >0.5 x 10(9)/l and platelet count of >50 x 10(9)/l were, respectively, 11 and 46. Eleven patients relapsed 3 to 50 months after PBSCT, and currently seven patients (5/13 who were transplanted in CR and 2/7 in PR) are surviving disease-free at 52 to 84 months. Although the retrospective nature of this study and several variables prevent a meaningful analysis, the overall results still support the feasibility of developing a prospective study of PBSCT with a larger number of children with high-risk neuroblastoma.

Child↗
PubMed1998

Clinically applicable bulk isolation of blood CD34+ cells for autografting in children.

CD34+ cells were purified in bulk from apheresis-collected cells of children with cancer using monoclonal antibody (MoAb) and magnetic beads (Baxter ISOLEX system). To improve the purity of the final product for possibly better tumor cell purging and to make the manufacturer's original procedure more cost-effective, we incubated the cells for 30 min with l-phenylalanine methylester hydrochloride (PME) to reduce the cell number by removing contaminating granulocytes and monocytes in the initial step before incubation with MoAb. Our modification prevented nonspecific interactions between MoAb and magnetic beads, and thereby saved expensive materials for purification. A total of 40 purifications were performed with samples containing a mean of 3.1 x 10(9) blood cells mobilized from 15 children by chemotherapy plus granulocyte colony-stimulating factor (G-CSF). The entire purification procedure, from the end of apheresis to storage, was completed within 5h. After incubation with PME and double-layered (40/60%) Percoll separation, the number of CD34+ cells was reduced to 48+/-29%, which suggests the possibility that half of the CD34+ cells in the inoculum were nonclonogenic in the hematopoietic progenitor assay. PME/Percoll-treated cells were then subjected to a final isolation procedure with MoAb according to the manufacturer's suggestions, and 52+/-42% and 32+/-22%, respectively, of the CFU-GM and CD34+ cells present in the initial bag inoculums were recovered. The recovery rates were, respectively, 54% and 67%, when the calculation was limited to the isolation procedure with MNoAb. The purity of isolated CD34+ cells and the plating efficiency in methylcellulose culture were, respectively, 77+/-24% and 33+/-13%. Fourteen children were subsequently autografted with purified CD34+ cells after marrow ablative chemotherapy. The median number of days to achieve an ANC of 0.5 x 10(9)/l was 12 and that to achieve a platelet count of 50 x 10(9)/l was 22.5, which were comparable to those in our historical group of 55 patients who underwent transplant with unmanipulated blood cells (13 and 16 days). These results suggest that our modified purification procedure with PME is useful for the initial reduction of cell numbers to save costly materials, and that cells isolated by this procedure can be directly used in clinical transplantation procedures.

Adolescent↗
PubMed1998

Intra-apheresis recruitment of blood progenitor cells in children.

BACKGROUND: Determination of the optimal duration of apheresis requires a careful examination of blood progenitor cell (BPC) kinetics during apheresis. Intra-apheresis recruitment of BPCs should be evaluated. STUDY DESIGN AND METHODS: Twenty-six apheresis procedures were performed in 13 children with various malignant disorders (ages, 10 months to 17 years; median, 7 years) to collect BPCs for autologous transplant, using a blood cell separator with 2 to 5.2 blood volumes processed. The subjects were divided into three groups according to age: below 1 year (n = 4), 2 to 10 years (n = 5), and 11 to 20 years (n = 4). BPCs were mobilized by a combination of chemotherapy and granulocyte-colony-stimulating factor (G-CSF; 2-7.5 micrograms/kg/day intravenous drip). The levels of circulating CD34+ cells and colony-forming units-granulocyte-macrophage (CFU-GM) were monitored to examine intra-apheresis recruitment. For every 50 mL per kg or 2 L of processed blood, 5-mL blood samples were collected via a central line. RESULTS: In the first apheresis procedure, more CD34+ cells were mobilized by the procedure itself in the infant group than in the older groups, and the number of cells decreased with the subject's age. When the same analysis was made during the second apheresis procedure, performed 1 day later, the levels of both CD34+ cells and CFU-GM had decreased to below the preapheresis values in all of the populations. Cell yields in the second apheresis procedure were significantly lower than those in the first. CONCLUSION: Although several factors prevent a reliable analysis, the data suggest that the intra-apheresis recruitment of BPCs may be age-specific; the continuous and prolonged supply of cells from the bone marrow to peripheral blood that occurs during apheresis is more predominant in infants, which leads to the collection of proportionately more BPCs in younger children than in their older counterparts.

Adolescent↗
PubMed1998

Continuous monitoring of hematocrit values during apheresis for allogeneic peripheral blood stem cell collection.

Rapid changes in the circulating blood volume or hemoglobin level during apheresis may pose a risk for healthy individuals donating allogeneic PBSC. In this study, a real-time noninvasive monitor CRIT-LINE was used for continuous monitoring of hematocrit values in a total of 16 aphereses performed in 4 adult (median age 30 years) and 4 pediatric donors (4 years). Donors received recombinant G-CSF (10 microg/kg s.c. for 5 days) for mobilization of PBSC. A CS3000 plus blood cell separator (Baxter) was used in two different procedures. Adults donors were subjected to modified program 1-120 using a combination of the granulocyte chamber and the small volume collection chamber (SVCC), and pediatric donors were subjected to specialized program 4 with a combination of the newly developed small volume separation chamber holder (SVSCH) and SVCC. In all of the procedures for children, the extracorporeal line was primed with 400 ml leukocyte-depleted allogeneic RBC or 200 ml autologous RBC after regular priming with normal saline, whereas none of the adult donors received this treatment. We found a marked contrast in the hematocrit kinetics during apheresis in the two cohorts/procedures. In adults, the initiation of apheresis was followed by an immediate decline in the hematocrit value over the initial 10 min until a stable plateau level was reached (7% decrease). In children, the values decreased slowly but progressively throughout the entire procedure to finally reach a 9% decrease at the completion of apheresis. These data may suggest that the use of SVSCH plus SVCC or priming with RBC can eliminate the abrupt decline in blood hemoglobin levels that occurs during apheresis.

Adult↗
PubMed1998

Total parenteral nutrition on energy metabolism in children undergoing autologous peripheral blood stem cell transplantation.

The resting energy expenditure (REE) and the respiratory quotient (RQ) were measured longitudinally using indirect calorimetry to examine the effects of total parenteral nutrition (TPN) on energy metabolism in children undergoing autologous peripheral blood stem cell transplantation (PBSCT). There were six children (two males and four females) and the age ranged from five to 13 years (median, eight yrs). The diagnosis included acute lymphocytic leukemia (ALL; 4), neuroblastoma (NBL; 1) and primitive neuroectodermal tumor (PNET; 1). TPN was started after the patients were stabilized following PBSCT (group A; n = 3) or before the initiation of high-dose cytoreductive chemotherapy (HCC) (group B; n = 3). Duration of HCC before PBSCT was identical between the two groups (six to eight days). Average total calorie and protein intake during HCC was significantly higher for group B than for group A. The %REE, the percentage of REE to the predicted basal energy expenditure (BEE), in group A showed 133 +/- 19%, 129 +/- 14% and 146 +/- 11% during three periods of HCC (days -8 to -1 of PBSCT), bone marrow suppression (days 0 to 11 of PBSCT) and bone marrow recovery (days 12 to 22 of PBSCT), respectively. In contrast, those in group B were 10% to 20% lower than those in group A at all periods. Carbohydrate oxidation rates during HCC in group A were significantly lower than those in group B, and those were not different between both groups during post-PBSCT periods. Fat oxidation rates in both groups were similar at all stages of periods. In contrast, protein degradation rates in group A were significantly higher than those in group B at all stages of the period. From these results, we concluded that commencement of TPN administration prior to HCC in the patients undergoing PBSCT provides beneficial effects to maintain better energy metabolic and nutritional status.

Adolescent↗
PubMed1998

Peripheral blood stem cell mobilization with granulocyte colony-stimulating factor and a harvesting procedure in pediatric donors.

The safety of injecting healthy donors with granulocyte colony-stimulating factor (G-CSF) has not been established. To evaluate PBSC mobilization and harvesting efficacy in the pediatric population, we compared it with those in adult donors. In this study, we conclude that PBSC mobilization and harvesting protocol in normal pediatric donors can be performed safely and effectively. Considering the lower frequency of side-effects and WBC counts, and G-CSF kinetics, higher dose of G-CSF would be recommended when small children become donors for adult patients.

Adolescent↗
PubMed1998

Transplantation with peripheral blood stem cells, manipulated or unmanipulated, for the treatment of high-risk childhood leukemia.

Collection of peripheral blood stem cells (PBSC) does not require anesthesia or multiple marrow aspirations, and hence, is far less invasive than bone marrow collection. Most importantly, PBSC can be collected from the body's entire pool of HSC to provide more stem cells than marrow aspiration performed at localized iliac bones. This leads to the faster recovery of hematopoiesis after PBSC transplantation (PBSCT) than after bone marrow transplantation and makes 'cell component therapy' far more effective with PBSC. This review will present our pediatric experience of transplants with PBSC, purified or unmanipulated.

Child↗
PubMed1997

Serum thrombopoietin levels in patients receiving high-dose chemotherapy with support of purified peripheral blood CD34+ cells.

In a case control study, serum levels of thrombopoietin (TPO) were determined by a sandwich ELISA in 20 patients (median age, 7 years; range, 2-56 years) with various malignancies who received high-dose chemotherapy and a stem cell rescue operation. The patients received two different transplant modalities: (a) 12 patients received purified autologous peripheral blood CD34+ cells; and (b) 8 patients received cells in the CD34(-) fraction, which still contains many CD34+ cells. No significant differences were observed between the two groups with regard to the duration required to achieve an absolute granulocyte count of >0.5 x 10(9)/liter, the duration of dependence on platelet transfusion, or the number of platelet transfusions. In both groups, the serum TPO levels were inversely correlated with the circulating platelet count. Multivariate analysis demonstrated that significant determinants of the serum TPO level included the circulating platelet count (standardized regression coefficient = -0.5179), transplantation with cells in the CD34(-) fraction (0.2414), solid tumor (0.1420), and the age of the patient (-0.1236; r2 = 0.3021; P < 0.0001). These results suggest that the mode of stem cell support (ie., the presence of accessory cells in the inoculum), age, or the type of preceding chemotherapy affects serum TPO levels after transplantation.

Adolescent↗