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O Ringdén

Publications and source records attributed to O Ringdén.

At least 37 records · Page 2Linked to original sources
PubMed2003

The effect of metronidazole on busulfan pharmacokinetics in patients undergoing hematopoietic stem cell transplantation.

Busulfan (Bu) is an important component of some myeloablative regimens prior to stem cell transplantation (SCT). Over the last few years it has been shown that other drugs administered concomitantly can influence Bu pharmacokinetics. In the present study, we compared Bu concentrations (trough levels) in three groups of patients. Group A (n=5) received metronidazole as graft-versus-host disease prophylaxis during Bu treatment. Group B (n=9) received Bu only for 2 days followed by 2 days of Bu and metronidazole. Group C (n=10) was a control group that received Bu without metronidazole. The mean Bu levels for Group A receiving metronidazole during conditioning was significantly (P<0.001) higher (948+/-280 ng/ml), compared to those observed in the control group (507+/-75 ng/ml). In Group B, the administration of metronidazole resulted in a significant (P<0.001) increase in Bu levels (807+/-90 ng/ml) during the last 2 days, compared to 452+/-68 ng/ml during the first 2 days. In Group A, one patient died with multiorgan failure, three experienced veno-occlusive disease (VOD) and one developed hemorrhagic cystitis. Elevated liver transaminases (AST, ALT) and bilirubin were detected in all Group A patients. In Group B, six patients had elevated liver function tests but no VOD was observed. We conclude that metronidazole should not be administered simultaneously with Bu to avoid the high plasma levels of Bu, which may lead to severe toxicity and/or treatment related mortality.

Adolescent↗
PubMed2003

G-CSF given after haematopoietic stem cell transplantation using HLA-identical sibling donors is associated to a higher incidence of acute GVHD II-IV.

The effect of granulocyte colony-stimulating factor (G-CSF), given after transplantation, was studied in 155 patients transplanted with haematopoietic stem cells (HSCT) from HLA-identical sibling donors at Huddinge University Hospital between 1993 and 2001. Only patients with haematological malignancies were included. Conditioning consisted of total-body irradiation in 118 and busulphan in 37 patients. They were all given methotrexate combined with cyclosporine as graft-versus-host disease (GVHD) prophylaxis. Of the 155 patients, 66 (43%) received G-CSF after HSCT. Those given G-CSF had a significantly shorter time to neutrophil engraftment (P <0.001). G-CSF treatment had no effect on erythrocyte transfusions, platelet engraftment and infections. However, patients treated with G-CSF had a significantly higher incidence of grades II-IV acute GVHD than those not given this treatment (34 vs 9%, P <0.001). The multivariate analysis showed that the effect of G-CSF was independent of other known risk factors for grades II-IV acute GVHD. Death from GVHD occurred in four and two cases (P=0.06) in the two groups, respectively. The cumulative incidences of transplant-related mortality, survival, chronic GVHD, relapse and relapse-free survival were similar in both groups. In conclusion, G-CSF given after HLA-identical sibling HSCT was associated with a higher risk of grades II-IV acute GVHD, but not transplant-related mortality.

Acute Disease↗
PubMed2003

Immunomodulatory effects of human foetal liver-derived mesenchymal stem cells.

Adult mesenchymal stem cells (MSCs) have been suggested to decrease lymphocyte proliferation in vitro. We hypothesised that foetal MSCs (fMSCs) would have an immunosuppressive effect on allograft responses in vitro. Human MSCs were isolated and cultured from first-trimester foetal livers and characterised by flow cytometry. fMSC stained positive for CD29, CD44, CD166, CD105, SH-3 and SH-4, and negative for CD14, CD34 and CD45. When plated on adipogenic, chondrogenic and osteogenic media, fMSC differentiated into the respective cell lineage. Compared to adult MSC (aMSC), the proliferative capacity of fMSC was higher. Mitogen stimulation of PBL was inhibited by fMSC. The greatest inhibition (78%) was seen when 30,000 fMSCs were added to 150,000 lymphocytes stimulated by phytohaemagglutinin. Adult and fMSCs were added to mixed lymphocyte cultures (MLC) containing peripheral blood lymphocytes or foetal liver cells. Unlike aMSC, fMSCs did not inhibit MLC. fMSC could be culture-expanded several million folds with no loss of phenotype characteristics, which makes them ideal for ex vivo expansion. fMSC inhibit lymphocyte proliferation induced by mitogens, but not alloreactivity as measured by MLC.

Adolescent↗
PubMed2003

N-acetyl-L-cysteine does not affect the pharmacokinetics or myelosuppressive effect of busulfan during conditioning prior to allogeneic stem cell transplantation.

Busulfan is currently used as a main component in the conditioning regimen prior to allogeneic stem cell transplantation (SCT). Several studies have shown a correlation between exposure to busulfan and transplantation-related liver toxicity, such as venoocclusive disease (VOD) in patients undergoing SCT. Busulfan is metabolized mainly through glutathione (GSH). During high-dose therapy, busulfan may deplete hepatocellular levels of GSH. As part of the conditioning therapy, busulfan is usually followed by high doses of cyclophosphamide. The activation of cyclophosphamide yields a cytotoxic metabolite, 4-hydroxy cyclophosphamide, which is highly reactive and detoxified through GSH. According to recent studies using cell lines and animal models N-acetyl-L-cysteine (NAC), a GSH precursor, does not hamper the myeloablative effect of busulfan during conditioning. In the present study, we administered NAC during conditioning to 10 patients at risk of VOD due to pretransplant liver disorders or elevated liver enzymes. No side effects related to the NAC infusions were observed and busulfan concentrations were not affected. All patients became pancytopenic and engrafted with 100% donor cells. None of the patients developed VOD or liver failure. Increased liver enzymes during conditioning decreased or normalized in all patients. We suggest that NAC therapy is safe and does not impair the myeloablative effect of busulfan during conditioning prior to SCT.

Acetylcysteine↗
PubMed2003

Mesenchymal stem cells inhibit and stimulate mixed lymphocyte cultures and mitogenic responses independently of the major histocompatibility complex.

We aimed to study the effects of mesenchymal stem cells (MSCs) on alloreactivity and effects of T-cell activation on human peripheral blood lymphocytes (PBLs) in vitro. MSCs were expanded from the bone marrow of healthy subjects. MSCs isolated from second to third passage were positive for CD166, CD105, CD44, CD29, SH-3 and SH-4, but negative for CD34 and CD45. MSCs cultured in osteogenic, adipogenic or chondrogenic media differentiated, respectively, into osteocytes, adipocytes or chondrocytes. MSC added to PBL cultures had various effects, ranging from slight inhibition to stimulation of DNA synthesis. The stimulation index (SI = (PBL + MSC)/PBL) varied between 0.2 and 7.3. The SI was not affected by the MSC dose or by the addition of allogeneic or autologous MSCs to the lymphocytes. Suppression of proliferative activity was observed in all experiments after the addition of 10,000-40,000 MSCs to mixed lymphocyte cultures (MLCs). Lymphocyte proliferation was 10-90%, compared with a control MLC run in parallel without MSCs. In contrast, the addition of fewer MSCs (10-1000 cells) led to a less consistent suppression or a marked lymphocyte proliferation in several experiments, ranging from 40 to 190% of the maximal lymphocyte proliferation in control MLCs. The ability to inhibit or stimulate T-cell alloresponses appeared to be independent of the major histocompatibility complex, as results were similar using 'third party' MSCs or MSCs that were autologous to the responder or stimulating PBLs. The strongest inhibitory effect was seen if MSCs were added at the beginning of the 6 day culture, and the effect declined if MSCs were added on day 3 or 5. Marked inhibitory effects of allogeneic and autologous MSCs (15,000) were also noted after mitogenic lymphocyte stimulation by phytohaemagglutinin (median lymphocyte proliferation of 30% of controls), Concanavalin A (56%) and protein A (65%). Little, if any, inhibition occurred after stimulation with pokeweed mitogen. Low numbers of MSCs (150 cells) were unable to inhibit mitogen-induced T-cell responses. MSCs have significant immune modulatory effects on MLCs and after mitogenic stimulation of PBL. High numbers of MSCs suppress alloreactive T cells, whereas very low numbers clearly stimulated lymphocyte proliferation in some experiments. The effect of a larger number of MSCs on MLCs seems more dependent on cell dose than histocompatibility and could result from an 'overload' of a stimulatory mechanism.

Adolescent↗
PubMed2002

Transplantation of peripheral blood stem cells as compared with bone marrow from HLA-identical siblings in adult patients with acute myeloid leukemia and acute lymphoblastic leukemia.

PURPOSE: Several studies show that allogeneic peripheral blood stem cells (PBSCs) engraft more rapidly than bone marrow (BM). However, the data are inconsistent with regard to acute and chronic graft-versus-host disease (GVHD), relapse, transplant-related mortality (TRM), and leukemia-free survival (LFS). PATIENTS AND METHODS: Between January 1994 and December 2000, 3,465 adult patients (older than 15 years of age) were reported to the European Group for Blood and Marrow Transplantation Registry from 224 centers. Among acute myeloid leukemia (AML) patients, 1,537 patients received BM and 757 patients received PBSC. In acute lymphoblastic leukemia (ALL) patients, the corresponding figures were 826 versus 345 patients who were analyzed for engraftment, GVHD, TRM, relapse, LFS, and survival. RESULTS: In multivariate analysis, the recovery of neutrophils and platelets was faster with PBSC than with BM (P <.0001). Chronic GVHD was associated with PBSC in patients with AML (relative risk [RR], 2.11; 95% confidence interval, 1.66 to 2.7; P <.0001) and ALL (RR, 1.56; 95% confidence interval, 1.09 to 2.27; P =.02). PBSC versus BM in patients with AML or ALL was not significantly associated with acute GVHD, TRM, relapse, survival, or LFS. In multivariate analysis of patients with AML, factors significantly associated with improved LFS included first remission at transplant (P <.0001), promyelocytic leukemia (M3) versus other French-American-British types (P <.0001), and donor age below median 37 years (P =.02). In patients with ALL, first remission (P <.0001) and methotrexate included in the immunosuppressive regimen (P =.001) were associated with improved LFS. CONCLUSION: Allogeneic PBSC results in faster neutrophil and platelet engraftment and a higher incidence of chronic GVHD than BM. However, acute GVHD, TRM, relapse, survival, and LFS were similar in patients receiving PBSCs versus BM.

Acute Disease↗
PubMed2002

CMV retinitis after allogeneic bone marrow transplantation: a report of five cases.

Four cases of cytomegalovirus (CMV) retinitis (CMVR) after allogeneic blood stem cell transplant (SCT) were documented in Huddinge University Hospital between 1994 and 1999. Prior to 1994, only one case was documented. All five patients were transplanted due to malignant disease, two with sibling donors and three with matched unrelated donors. Despite adequate antiviral treatment against CMV retinitis, the result has been almost total unilateral blindness in three patients. However rare, the complication seems to have become more common since we began doing more matched unrelated donor transplants, which leads to a more pronounced T-cell defect and to a delayed immune reconstitution compared to sibling transplants. We conclude that CMV retinitis is a rare but important complication to allogeneic blood stem cell transplantation.

Acyclovir↗
PubMed2002

Association between pretransplant Thymoglobulin and reduced non-relapse mortality rate after marrow transplantation from unrelated donors.

A matched cohort study was designed to test the efficacy of polyclonal rabbit antiserum specific for human T cells (Thymoglobulin), administered in vivo on days 1-5 (2 mg/kg/day) before T cell-replete unrelated donor marrow transplantation. Thymoglobulin was given to 52 leukemic patients at Huddinge Hospital. Control patients matched for diagnosis, disease stage, age and treated with a similar regimen, apart from the omission of Thymoglobulin, were selected in Seattle during the same period (n = 104). All received conditioning with cyclophosphamide and TBI. In the study group all patients received 10 Gy single dose TBI, while the controls were given 12-14.4 Gy fractionated TBI. GVHD prophylaxis was cyclosporine and methotrexate. Patients were treated for grade I acute GVHD in the study group, and for grade II GVHD in the control group. Multivariable analyses were adjusted for patient and donor age and CMV serology, HLA matching, donor gender and marrow cell dose. Non-relapse mortality was lower in the study patients (hazard ratio = 0.30, 95% CI 0.12-0.75, P value = 0.005). The 5-year cumulative incidence of non-relapse mortality was 19% in the study cohort, and 35% in the control cohort. Overall mortality was also lower in study patients (hazard ratio 0.51, 95% CI 0.27-0.97, P value = 0.03). No significant difference in the risk of relapse was seen (P = 0.63). This suggests that Thymoglobulin during conditioning may reduce non-relapse mortality after unrelated donor marrow transplantation.

Adolescent↗
PubMed2002

The graft-versus-leukaemia effect in haematopoietic stem cell transplantation using unrelated donors.

We studied the graft-versus-leukaemia (GVL) effect in 185 patients with haematological malignancies who underwent unrelated donor haematopoietic stem cell transplantation (HSCT) at Huddinge University Hospital between May 1991 and June 2001. Ninety-five were in first CR/CP and 90 in later stages. Most (86%) of them had a HLA-A, -B and -DRbeta1 matched donor. Conditioning usually consisted of total body irradiation and cyclophosphamide, and GVHD prophylaxis of cyclosporine and methotrexate. In the multivariate risk-factor analysis of relapse, we found that disease stage beyond CR1/CP1 (P = 0.02), acute GVHD 0-I (P = 0.02), absence of chronic GVHD (P = 0.02) and ALL (P = 0.02) were independent risk factors for relapse. The incidence of relapse in those with acute GVHD grade II was 18% vs 46% in those with no or grade I (P = 0.04). In patients with or without chronic GVHD, the incidences of relapse were 32% and 48%, respectively (P < 0.01). The best RFS was seen in patients with chronic GVHD. No difference in RFS was seen in patients with no, mild or moderate acute GVHD. Risk factors for relapse after HSCT with unrelated donors were: acute lymphoblastic leukaemia, disease stage beyond CR1/CP1, absence of chronic GVHD and no, or mild acute GVHD. Overall and relapse-free survival were not improved by the occurrence of acute GVHD.

Adolescent↗
PubMed2002

A phase II trial of liposomal busulphan as an intravenous myeloablative agent prior to stem cell transplantation: 500 mg/m(2) as a optimal total dose for conditioning.

We conducted a phase I/II trial, to evaluate the efficacy and safety of an intravenous liposomal formulation of busulphan (LBu) as a myeloablative agent for stem cell transplantation (SCT). The liposomal busulphan was administered as a 3 h infusion twice daily over 4 consecutive days. Six adults received 1.6-2 mg/kg/dose and 18 children received 1.8-3 mg/kg/dose. Pharmacokinetic parameters were studied after the first and the last dose of busulphan. No significant difference in clearance, AUC, elimination half-lives or distribution volume between the first and the last dose was found in either groups. A significantly (P < 0.005) higher clearance was observed in children after the first and the last dose (3.61 and 3.79 ml/min/kg, respectively) compared to adults (2.40 and 2.33 ml/min/kg, respectively). The elimination half-lives after the first and the last dose were significantly (P < 0.005) shorter in children (2.59 and 2.72 h, respectively) compared to adults (3.35 and 3.61 h, respectively). Clearance correlated significantly with age. However, no significant correlation with age was observed when clearance was adjusted to the body surface area. Two cases of VOD following a total dose of 24 mg/kg were observed. Six patients experienced mucositis. No other organ toxicity was observed. We conclude that intravenous liposomal busulphan pharmacokinetics is age dependent. A dosage schedule based on body surface area should be used especially in young children to reduce the age-dependent difference in kinetics. An intravenous liposomal dose of busulphan of 500 mg/m(2) is suggested to reach a similar systemic exposure and myeloablative effect in both children and adults. Moreover, the novel liposomal form of busulphan showed a favorable toxicity profile and seems safe as a part of the high-dose therapy prior to SCT.

Adult↗
PubMed2002

Response of in vivo protein synthesis in T lymphocytes and leucocytes to an endotoxin challenge in healthy volunteers.

In vivo determination of protein synthesis in immune cells reflects metabolic activity and immunological activation. An intravenous injection of endotoxin to healthy volunteers was used as a human sepsis model, and in vivo protein synthesis of T lymphocytes and leucocytes was measured. The results were related to plasma concentrations of selected cytokines, peripheral cell counts and subpopulations of immune cells. The subjects (n = 8 + 8) were randomized to an endotoxin (4 ng/kg) or a saline group. In vivo protein synthesis was determined twice: before and 1-2.5 h after the endotoxin/saline injection. Protein synthesis decreased in isolated T lymphocytes, but increased in leucocytes. Plasma levels of TNF-alpha, IL-8, IL-6, IL-1 ra and IL-10 were elevated, whereas IL-2 and IFN-gamma, produced predominantly by T lymphocytes, did not change in response to endotoxin. Neutrophils increased, whereas lymphocytes and monocytes decreased 2.5 h after the endotoxin injection. Flow cytometry revealed a drop in total CD3+ T lymphocytes and CD56+ natural killer cells, accompanied by an increase in CD15+ granulocytes. In summary, in vivo protein synthesis decreased in T lymphocytes, while the total leucocyte population showed a concomitant increase immediately after the endotoxin challenge. The changes in protein synthesis were accompanied by alterations in immune cell subpopulations and in plasma cytokine levels.

Adult↗
PubMed2002

Cytolytic T cell reactivity to Epstein-Barr virus is lost during in vitro T cell expansion.

In the setting of allogeneic hematopoietic stem cell transplantation, ex vivo culturing of donor T lymphocytes is a necessary step for processes such as gene modification. Often the aim is to enable control of undesired alloreactivity after in vivo administration of the cultured cells. However, it is not fully understood how T cell reactivity against donor and third-party targets is affected by the ex vivo cell culturing process. We have assessed how the activity of anti-Epstein Barr virus (EBV)-specific T lymphocytes from healthy EBV-seropositive donors is affected by in vitro cell culturing. Peripheral blood mononuclear cells (PBMCs) were expanded in X-VIVO 15 culture medium supplemented with 5% human serum. The cells were stimulated by either OKT3 (10 ng/ml) and interleukin (IL)-2 (500 U/ml) or by using anti-CD3/CD28-coated immunomagnetic beads and IL-2 (100 U/ml). Induction of polyclonal EBV-specific cytotoxic T lymphocyte cultures was attempted by stimulation of the in vitro-expanded cells at different time points during the cell expansion process, with pre-established autologous EBV-transformed lymphoblastoid cell lines (LCLs). While EBV-specific cytotoxic T lymphocytes (CTL) were generated from untreated PBMCs of 5 healthy donors, EBV-specific cytotoxicity was significantly decreased or absent in CTL cultures established from in vitro-expanded PBMCs. Our results indicate that the ex vivo cell expansion process itself significantly reduces the activity and/or the number of EBV-specific T cells. Additional stimulation with CD28 antibodies could not prevent this effect. Because T cell depleted bone marrow or stem cell grafts are known to contribute to the development of post transplant lymphoproliferative disorders, this should be taken into consideration if one considers expanding and administering PBMCs in conjunction with a T cell-depleted stem cell grafts.

Cell Culture Techniques↗
PubMed2001

No difference in graft-versus-host disease, relapse, and survival comparing peripheral stem cells to bone marrow using unrelated donors.

The clinical results in 107 patients receiving a peripheral blood stem cell (PBSC) graft mobilized by granulocyte colony-stimulating factor (G-CSF) from HLA-A, -B, and -DR-compatible unrelated donors were compared to 107 matched controls receiving unrelated bone marrow (BM) transplants. Engraftment was achieved in 94% of the patients in both groups. The PBSC graft contained significantly more nucleated cells, CD34(+), CD3(+), and CD56(+) cells (P <.001), and resulted in a significantly shorter time-to-neutrophil (15 versus 19 days) and platelet engraftment (20 versus 27 days), compared to the BM control group (P <.001). Probabilities of acute graft-versus-host disease (GVHD) grades II to IV were 35% and 32% (not significant [NS]) and of chronic GVHD 61% and 76% (NS) in the PBSC and BM groups, respectively. There was no difference between the 2 groups in bacteremia, cytomegalovirus reactivation or disease, and fungal infection. The 3-year transplant-related mortality (TRM) rates were 42% in the PBSC group and 31% in the BM controls (P =.7) and the survival rates were 46% and 51%, respectively. The probability of relapse was 25% and 31% in both groups (NS), resulting in disease-free survival rates of 43% in the PBSC group and 46% in the BM controls (NS). In the multivariate analysis, early disease, acute GVHD grade 0 to I, and presence of chronic GVHD were independent factors associated with a better disease-free survival in this study. PBSC from HLA-compatible unrelated donors can be used safely as an alternative to BM for stem cell transplantation.

Adolescent↗
PubMed2001

The significance of graft-versus-host disease and pretransplantation minimal residual disease status to outcome after allogeneic stem cell transplantation in patients with acute lymphoblastic leukemia.

Relapse is the major cause of treatment failure after allogeneic stem cell transplantation (SCT) in patients with acute lymphoblastic leukemia. Minimal residual disease (MRD) was analyzed before SCT in 30 patients with acute lymphoblastic leukemia. The aim was to determine whether the level of MRD before transplantation was correlated with outcome. Fifteen patients were found to have high-level MRD (10(-2) to 10(-3)), 10 had low-level MRD (< 10(-3)), and 5 were MRD(-). Among MRD(-) patients the probability of relapse was 0 in 5, which was less than in MRD(+) patients (13 of 25) (P =.05). No major difference was found between the high- and low-level MRD(+) groups. Among the MRD(+) patients, only 2 of 11 with acute and chronic graft-versus-host disease had a relapse, versus 11 of 14 without (P =.005). In conclusion, for patients entering transplantation while they have residual disease, a combination of acute and chronic graft-versus-host disease may be needed to decrease the risk of relapse after SCT.

Adolescent↗
PubMed2001

No disadvantage in outcome of using matched unrelated donors as compared with matched sibling donors for bone marrow transplantation in children with acute lymphoblastic leukemia in second remission.

PURPOSE: We evaluated the outcome of children with acute lymphoblastic leukemia (ALL) in second remission (2CR), comparing bone marrow transplantation (BMT) using either matched sibling donors or unrelated donors (URDs). PATIENTS AND METHODS: A total of 65 patients, aged 2 months to 20 years at BMT, with ALL in 2CR underwent allogeneic BMT at seven Nordic centers during 1990 to 1997. Of the first relapses, 85% were in bone marrow; 46% occurred on therapy, and 54%, off therapy. The preparative regimens were cyclophosphamide plus total-body irradiation +/- antithymocyte/antilymphocyte globulin, busulfan plus cyclophosphamide +/- antithymocyte/antilymphocyte globulin, or cytarabine plus total-body irradiation. Of the allografts, 37 were from HLA-matched siblings and 28 were from URDs. RESULTS: In the sibling versus URD graft recipient groups, the posttransplantation 5-year event-free survival was 39% versus 54% (P =.4), the estimated posttransplantation relapse rate was 76% versus 40% (P = not significant [NS]), and the toxic death rate was 19% versus 11% (P = NS). The incidence of significant (grade 2 to 4) acute graft-versus-host disease (GVHD) was 38% versus 64% (P <.05) and was 14% versus 32% (P <.10) for severe (grade 3 to 4) acute GVHD; the incidence of chronic GVHD was 26% versus 57% (P <.05) and was 13% versus 22% (P = NS) for extensive chronic GVHD in the sibling and URD groups. CONCLUSION: BMT with matched URD allografts offers at least equal survival for children with ALL in 2CR, as compared with allografts from matched sibling donors. URD allografts were not associated with a higher toxic mortality rate, although both acute and chronic GVHD were more frequent with URD. Indications for using matched URD allografts in ALL 2CR can be considered the same as for using matched sibling donors.

Adolescent↗
PubMed2001

Impact of donor type on outcome of bone marrow transplantation for Wiskott-Aldrich syndrome: collaborative study of the International Bone Marrow Transplant Registry and the National Marrow Donor Program.

Human leukocyte antigen (HLA)-identical sibling bone marrow transplantation is an effective treatment for Wiskott-Aldrich syndrome. However, most children with this disease lack such donors and many patients receive transplants from alternative donors. This study compared outcomes of HLA-identical sibling, other related donor, and unrelated donor transplantation for Wiskott-Aldrich syndrome. The outcome of 170 transplantations for Wiskott-Aldrich syndrome, from 1968 to 1996, reported to the International Bone Marrow Transplant Registry and/or National Marrow Donor Program were assessed. Fifty-five were from HLA-identical sibling donors, 48 from other relatives, and 67 from unrelated donors. Multivariate proportional hazards regression was used to compare outcome by donor type and identify other prognostic factors. Most transplant recipients were younger than 5 years (79%), had a pretransplantation performance score greater than or equal to 90% (63%), received pretransplantation preparative regimens without radiation (82%), and had non-T-cell-depleted grafts (77%). Eighty percent received their transplant after 1986. The 5-year probability of survival (95% confidence interval) for all subjects was 70% (63%-77%). Probabilities differed by donor type: 87% (74%-93%) with HLA-identical sibling donors, 52% (37%-65%) with other related donors, and 71% (58%-80%) with unrelated donors (P =.0006). Multivariate analysis indicated significantly lower survival using related donors other than HLA-identical siblings (P =.0004) or unrelated donors in boys older than 5 years (P =.0001), compared to HLA-identical sibling transplants. Boys receiving an unrelated donor transplant before age 5 had survivals similar to those receiving HLA-identical sibling transplants. The best transplantation outcomes in Wiskott-Aldrich syndrome are achieved with HLA-identical sibling donors. Equivalent survivals are possible with unrelated donors in young children.

Actuarial Analysis↗
PubMed2001

T cell mixed chimerism is significantly correlated to a decreased risk of acute graft-versus-host disease after allogeneic stem cell transplantation.

BACKGROUND: It has been debated whether mixed chimerism (MC) is correlated to a decreased incidence of graft-versus-host disease (GVHD) after allogeneic stem cell transplantation (SCT). METHODS: Between September 1996 and April 1999 we analyzed 102 patients for MC in the T-cell fraction post allogeneic SCT, using PCR amplification of variable numbers of tandem repeat (VNTR) loci. All samples, taken regularly post SCT, were cell separated using anti-CD3 immunomagnetic beads. RESULTS: T-cell mixed chimerism was detected in 58 out of 102 patients (57%). Patient characteristics were comparable in the T-cell MC- and donor chimeric-group (DC). The median follow-up time for the MC group was 714 days (range 58 - 1248) as compared to 427 days (range 45 - 1042) for the DC group. Overall probability of acute GVHD grades II-IV was significantly higher in the DC group as compared to the MC group (52% vs. 5%, P<0.001). In multivariate analysis T-cell DC proved to be the most significant risk factor for acute GVHD grades II-IV. The cumulative incidence of relapse, among patients with malignant disease, did not show any statistical difference between the T-cell MC patients and the DC-group. There was a tendency for better overall survival in the T-cell MC group compared to the DC group (2 yrs; 73% vs. 54%, P=0.06). Among DC patients, 14/20 (70%) deaths were due to GVHD versus none in the MC-group(P<0.001). CONCLUSION: T-cell mixed chimerism was significantly correlated to a decreased risk of moderate to severe acute GVHD and death by GVHD.

Adolescent↗