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R Storb

Publications and source records attributed to R Storb.

At least 145 records · Page 8Linked to original sources

Molecular analysis of six dog leukocyte antigen class I sequences including three complete genes, two truncated genes and one full-length processed gene.

We have isolated six distinct dog leukocyte antigen (DLA) class I sequences. An additional functional nonclassical class I gene, DLA-79, was characterized previously. This brings the number of isolated canine class I sequences to seven. These seven loci account for nearly all class I sequences detected in genomic DNA by Southern blotting. With approximately seven members, the class I gene family in dog is considerably less complex than in either human or mouse. Three of the six sequences described in this article contain complete class I genes. These genes have the typical arrangement of exons and introns, and their predicted protein sequences have the features expected of expressed class I molecules. Two sequences contain truncated genes. These genes, having only partial class I homology and disruptive mutations, are clearly nonfunctional. The remaining locus contains a full-length processed gene which is unique among characterized class I loci. Sequence comparisons were performed to examine evolutionary relationships among the family members. Two sequences, DLA-64 (complete) and -53 (truncated), appear to be chimeras presumably formed by interlocus recombination. Using the reverse transcription-polymerase chain reaction, mRNA originating from each of the three complete genes was identified in canine peripheral blood leukocytes. DLA-79 specific transcripts were identified previously. Thus, each of the four complete canine class I genes is transcribed in vivo.

Amino Acid Sequence↗

Effect of different chemotherapy regimens on peripheral-blood stem-cell collections in patients with breast cancer receiving granulocyte colony-stimulating factor.

PURPOSE: To evaluate the effects of chemotherapy regimens on peripheral-blood stem-cell (PBSC) yields in patients with breast cancer who receive granulocyte colony-stimulating factor (G-CSF). PATIENTS AND METHODS: One hundred patients with breast cancer received cyclophosphamide 4 g/m2 for dose (CY) (n = 10), CY and etoposide 600 mg/m2 (CE) (n = 13), CE and cisplatin 105 mg/m2 (CEP) (n = 19), or CY and paclitaxel 170 mg/m2 (n = 58), followed by G-CSF. PBSC collections were initiated when the WBC count recovered to greater than 1 x 10(9)/L. A multivariate analysis was undertaken to evaluate the effects of different chemotherapy regimens and patient variables on PBSC collections as measured by the yield of CD34+ cells. RESULTS: The medians of average daily CD34+ cell yields for patients who received paclitaxel plus CY, CE, and CEP with G-CSF were 12.9, 11.03, and 5.37 x 10(6)/kg, respectively, compared with 2.02 x 10(6)/kg in the reference group that received CY with G-CSF (P = < .0001, .002, and .09, respectively). On first-day collections, patients who received paclitaxel plus CY, CE, and CEP with G-CSF yielded medians of 11.07, 8.09, and 3.52 x 10(6) CD34+ cells/kg, respectively, compared with 0.90 x 10(6)/kg in the reference group that received CY with G-CSF (P = .0006, .02, and .09, respectively). The number of previous cycles of chemotherapy, previous radiotherapy, marrow involvement, and phase and stage of disease did not have statistically significant effects on CD34+ cell yield. CONCLUSION: Combination chemotherapy regimens were superior to single-agent CY for the mobilization of CD34+ cells.

Antigens, CD34↗

Pre-existing autoimmune disease in patients with long-term survival after allogeneic bone marrow transplantation.

We reviewed the experience with allogeneic bone marrow transplantation (BMT) at Fred Hutchinson Cancer Research Center and affiliated Seattle hospitals for patients with preexisting autoimmune diseases. The review was limited to patients who received transplants between 1969 and 1989 from a related donor and who had at least 3 years of relapse-free survival. Of 901 evaluable patients, 11 were identified with a preexisting autoimmune disease and 2 with diseases that were possibly autoimmune in nature. Pretransplant diseases identified in this review included rheumatoid arthritis (n = 1), discoid or systemic lupus (n = 2), insulin dependent Type 1 diabetes (n = 3), hyperthyroidism (n = 4), dermatitis herpetiformis (n = 1), vasculitis (n = 1), and Crohn's disease (n = 1). All 13 patients survive with a median followup of 14 (range, 7-20) years after transplantation from an HLA identical sibling (n = 10), parent (n = 1) or identical twin (n = 2). Pre and post-transplant histories are presented. Variables to be considered in the assessment of any beneficial effect of BMT are discussed, including consideration of different patterns of activity that describe the natural history of various autoimmune diseases. Although autoimmune disease did not recur after allogeneic BMT in these 13 patients, disease and post-transplant variables may confound the interpretation of results from retrospective analysis.

Adolescent↗

Hematopoietic stem cell transplantation in nonmalignant diseases.

Treatment of patients with nonmalignant hematopoietic diseases by marrow grafts from HLA identical family members has progressed to a point where event free survivals of 75-90% can be expected. For allografts to be successful, conditioning programs have been devised that provide both the immunosuppression and the marrow space required for the incoming grafts to be accepted. Despite graft versus host disease prevention with methotrexate and cyclosporine, the acute and chronic forms of this disease continue to pose problems for a minority of patients after transplant, and they may necessitate prolonged courses of immunosuppressive therapy. The transplant procedures required for patients with these nonmalignant hematopoietic diseases could be directly applied to patients with autoimmune diseases.

Acute Disease↗

Development of a protocol for allogeneic marrow transplantation for severe systemic sclerosis: paradigm for autoimmune disease.

Some types of severe autoimmune disease are associated with significant morbidity and a high mortality rate. Many of these cases occur in young adults who, even if they survive, become severely debilitated. Systemic sclerosis (SSc) is a paradigm for other severe autoimmune diseases in which patients with poor prognostic features can be identified early in the course of the disease. Allogeneic marrow transplantation may be effective for the control of autoimmune diseases like SSc because the preparative regimen will significantly suppress the host immune system and the antihost effects of the donor immune system in the engrafted marrow will help maintain the suppression of the host immune system. Considering the morbidity and poor prognosis associated with severe SSc and the favorable outcome now associated with allogeneic marrow transplantation from HLA identical siblings for other nonmalignant diseases, Phase I and II studies are warranted. These will evaluate the safety of allogeneic marrow transplantation and explore its role in the management and control of a severe autoimmune disease. We review issues important in the development of an allogeneic marrow transplant protocol for severe SSc, including patient selection, plan of treatment, prevention of graft versus host disease, supportive care, and evaluation after transplant.

Adolescent↗

Autologous stem cell transplantation for autoimmune diseases: issues in protocol development.

For patients with autoimmune disease resistant to conventional therapy, aggressive strategies employing high dose chemoradiotherapy and autologous stem cell transplant appear to be warranted. Support for this approach comes from animal studies employing marrow transplantation, which have shown promising results. Likewise, longterm control of autoimmune disease has been demonstrated in some survivors of allogeneic transplants for malignancy who incidentally had preexisting autoimmune disease. Initial strategies for autografting will use intensive transplant regimens incorporating cyclophosphamide with or without total body irradiation. Peripheral blood stem cell grafts purified by CD34 selection will be depleted of lymphocytes, and lead to rapid hematologic reconstitution after treatment. Close monitoring for disease responses, adverse effects of intensive immunosuppression, and longterm sequelae of high dose therapies will be required. Initial studies are best performed as close collaborations between rheumatologists and transplant specialists in appropriate research centers.

Animals↗

Effect of recombinant canine stem cell factor, a c-kit ligand, on hematopoietic recovery after DLA-identical littermate marrow transplants in dogs.

We studied the effect of recombinant canine stem cell factor (rcSCF) on hematopoietic recovery, incidence of graft failure, graft-vs.-host disease (GVHD), and survival after marrow transplantation from dog leukocyte antigen (DLA)-identical canine littermates. Ten animals received 100 microg rcSCF/kg/day b.i.d. by subcutaneous injection on days 1 through 10 after 920 cGy total body irradiation and transplantation of a mean of 3.7x10(8) marrow cells/kg body weight. None of the dogs received GVHD prophylaxis. All animals showed hematopoietic engraftment. The median number of days to achieve 1000 neutrophils/mm3 was 9; 100 monocytes/mm3 were reached after 15 days, 500 lymphocytes/mm3 after 21 days, and 20,000 platelets/mm3 after 16 days. One animal developed GVHD involving skin, gut, and liver and died of bacterial pneumonia 21 days after transplantation. The remaining nine dogs were observed for a median of 37 days (range 29-84 days) posttransplantation until they were killed. Facial edema was seen in three dogs during the first 2-3 days of rcSCF administration. These results show that within the limits of this study it appears to be safe to administer SCF after DLA-identical littermate marrow transplants in dogs. Comparison with previously published data in the same model showed that neutrophil and monocyte recovery was significantly faster in dogs receiving SCF treatment compared with dogs without growth factor treatment (recovery to achieve 1000 neutrophils/mm3: median 9 days vs. 13 days, p = 0.002; recovery to 100 monocytes/mm3: median 15 days vs. 105 days, p = 0.0002). Otherwise, no significant differences were seen. Results obtained with SCF treatment were similar to those previously obtained in the same model with recombinant human granulocyte colony-stimulating factor (rhG-CSF) treatment except that recovery of lymphocytes to 500/mm3 appeared to be more rapid in G-CSF-treated dogs (median 15 days vs. 21 days, p = 0.03).

Animals↗

Methotrexate and cyclosporine for graft-vs.-host disease prevention: what length of therapy with cyclosporine?

One hundred three patients with leukemia, aplastic anemia, or myelodysplastic syndrome were treated by marrow transplantation from genotypically HLA-identical siblings (n = 92) or HLA haploidentical family members differing for one HLA antigen on the nonshared haplotype (n = 11). To prevent graft-vs.-host disease (GVHD), they were administered postgrafting immunosuppression with a short course of intermittent methotrexate with daily cyclosporine for no more than 11 days. Customarily, we have given cyclosporine for 180 days after transplant. In the current study, we asked whether cyclosporine could be stopped earlier without affecting the risk of chronic GVHD. By day 60, patients who never had acute GVHD, or whose acute GVHD had resolved, were randomized to have cyclosporine stopped (n = 52) or continued for the usual 180 days (n = 51). Results were analyzed with a median follow-up of 9.3 years after transplant, and showed that patients in whom cyclosporine was discontinued on day 60 had a significantly more rapid onset (p = 0.001), but not a significantly higher overall incidence of chronic GVHD than those in whom the drug was stopped on day 180 (43 vs. 54%; p = 0.26). Transplant-related mortality was comparable among patients without preceding acute GVHD, regardless of when cyclosporine was discontinued (11% for both study arms). However, transplant-related mortality appeared to increase among patients with preceding acute GVHD in whom cyclosporine was stopped by day 60 (38 vs. 17%). Results suggest that cyclosporine can safely be discontinued early in patients who never had evidence of acute GVHD, while those with preceding acute GVHD would benefit from a longer course of the drug. Because of the relatively small sample sizes, these results would best be treated as promising preliminary findings that should be confirmed in larger randomized studies.

Adult↗

Transplantation of allogeneic CD34+ peripheral blood stem cells in patients with advanced hematologic malignancy.

Sixteen patients with advanced hematologic malignancies were transplanted with HLA-identical allogeneic peripheral blood stem cells (PBSCs) that were selected for CD34+ cells by an avidin-biotin immunoadsorption technique. The median age of patients was 48 years (range, 37 to 67). Patients received 12.0 or 13.2 Gy of total body irradiation followed by 120 mg/kg of cyclophosphamide. Normal donors received 16 mg/kg of granulocyte-colony stimulating factor on days 1 to 6 followed by PBSC harvests on days 4 to 7. PBSC harvests were processed each day on a single avidin-blotin column containing an antibody to the CD34 antigen and processed cells were infused without cryopreservation daily for 4 consecutive days. Prophylaxis against graft-versus-host disease (GVHD) consisted of cyclosporine alone for 5 patients and CSA plus methotrexate for 11 patients. A median of 18.64 (6.74 to 34.97) x 10(8) CD34+ cells/kg patient body weight were collected from each donor. A median of 8.96 (2.62 to 17.34) x 10(8) CD34+ cells/kg patient body weight were recovered after avidin-biotin adsorption which represented a median CD34+ cell yield of 53% (18% to 77%) with a median purity of 62% (34% to 82%). There was a reduction in CD3+ cells from a median of 557.26 (227.73 to 677.77) x 106/kg to 0.73 x 10(4)/kg (0.40 to 3.65), in CD4+ cells from 351.72 (194.47 to 520.11) x 10(6)/kg to 0.40 (0.15 to 1.03) x 10(4)/kg and in CD8+ cells from 169.74 (53.34 to 325.83) x 10(6)/ kg to 0.32 (0.12 to 2.71) x 10(4)/kg representing a median 2.8 (2.19 to 3.14) log reduction in T cells. One patient died of infection on day 3 posttransplant and was unevaluable for recovery of neutrophils. The median day to recovery of 500 neutrophils/mL was 15 (8 to 26) in the remaining 15 patients. Six of 16 patients falled to achieve a platelet count of 20,000/mL before death on days 3 to 97 of transplant-related complications. The median day to achieving platelets of 20,000 mL in the remaining 10 patients was 11 (7 to 31). Eight of 16 patients (50%) died between 3 and 97 days posttransplant, 7 of transplant-related causes, and 1 of progressive disease. Grade 2-4 acute GVHD occurred in 12 out of 14 (86%) and grades 3-4 in 6 out of 14 (43%) evaluable patients. Six of 8 evaluable patients developed clinical chronic GVHD and 1 developed subclinical chronic GVHD. Bone marrow and/or peripheral blood chimerism studies in 12 evaluable patients showed 97% to 100% donor type in 11 patients with 1 patient in relapse showing 40% donor cells 60 to 90 days posttransplant. Four of 16 patients (25%) are alive and disease-free 312 to 576 days after transplant. There were no episodes of graft failure or rejection. This study shows that allogeneic transplantation using CD34+ selected PBSC results in prompt and sustained engraftment. CD34+ selection, as employed in this preliminary study, however, resulted in an apparently higher rate of acute and chronic GVHD. However, The sample size is quite small and precludes a more definitive conclusion regarding GVHD.

Adult↗

FK506 in combination with methotrexate for the prevention of graft-versus-host disease after marrow transplantation from matched unrelated donors.

The safety and potential efficacy of FK506 in combination with a short course of methotrexate (MTX) for the prevention of acute graft-versus-host disease (GVHD) after marrow transplantation from HLA-matched unrelated donors was evaluated in a single-arm Phase II study conducted at two centers. Forty-three patients, 15 to 54 (median 41) years of age, were transplanted for hematologic malignancies. Thirty-seven of 43 evaluable patients had evidence of sustained marrow engraftment. Five patients died before day 17 after transplantation. The median time to an absolute neutrophil count of > 0.5 x 10(5)/L was 21 (range, 14 to 30) days. Nephrotoxicity (serum creatinine concentration > 2 mg/dL or doubling of baseline) occurred in 32 patients (74% cumulative incidence during the first 100 days after transplant). Other adverse effects included hypertension (n = 27), hyperglycemia (n = 27), neurotoxicity (n = 9) and thrombotic thrombocytopenic purpura (n = 2). Severe veno-occlusive disease of the liver occurred in 9 (21%) of the 43 patients. Eighteen patients (42%) developed grades II to IV acute GVHD and five (12%) developed grades III to IV acute GVHD. Twelve of 25 evaluable patients developed extensive chronic GVHD within 1 year of marrow transplantation resulting in an estimate of the probability of developing this complication of 48%. The cumulative incidence of transplant-related mortality during the first 100 days was 37%. Kaplan-Meier estimates of disease-free survival at 2 years for good-risk, poor-risk, and all patients were 65%, 4%, and 32%, respectively. FK506 in combination with a short course of MTX appears active in preventing acute GVHD after marrow transplantation from unrelated donors. Further studies comparing the combination of FK506 and MTX with cyclosporine and MTX for the prevention of acute GVHD are warranted.

Adolescent↗

Allogeneic marrow transplantation for multiple myeloma: an analysis of risk factors on outcome.

Between September 1987 and December 1994, 80 patients with multiple myeloma (MM) received high-dose busulfan and cyclophosphamide without (n = 57) or with modified total body irradiation (n = 23) followed by marrow from allogeneic donors. At transplant, 71% of the patients had disease that was refractory to chemotherapy. Thirty-five patients died of transplant-related causes within 100 days and 11 deaths occurred later. The actuarial probabilities of survival and progression-free survival were .24 +/- 0.17 and .20 +/- 0.10 at 4.5 years. Complete remissions were obtained in 36% of patients who had actuarial probabilities of survival and event-free survival of .50 +/- 0.21 and .43 +/- 0.17 at 4.5 years. In a multivariate analysis, adverse risk factors for outcome endpoints included: transplantation greater than 1 year from diagnosis; beta-2 microglobulin > 2.5 at transplant; female patients transplanted from male donors; patients who had received greater than eight cycles of chemotherapy before transplant and Durie stage 3 disease at the time of transplant. These results indicate that allografting for patients with MM can result in long-term disease-free survival for a minority of patients. Efforts to reduce transplant-related mortality should focus on earlier transplantation, less toxic treatment regimens, better supportive care, and improved prevention and treatment of graft-versus-host disease (GVHD).

Adult↗

Allogeneic peripheral blood stem cell transplantation in patients with advanced hematologic malignancies: a retrospective comparison with marrow transplantation.

Allogeneic peripheral blood stem cell (PBSC) transplants from HLA-identical siblings were performed in 37 patients with advanced hematologic malignancies. Outcomes were compared to a historical group of 37 similar patients with advanced hematologic malignancies receiving bone marrow (BM) transplants from HLA-identical donors. The PBSC group and historical BM group were well matched for diagnosis, disease stage, age, and graft-versus-host disease (GVHD) prophylaxis. Patients received PBSC transplants between 1993 to 1995 while BM patients were treated between 1989 to 1994. Engraftment, measured by the time to reach a peripheral neutrophil count > 500/L and platelet count > 20,000/microL without transfusions, occurred on days 14 and 11 in the patients transplanted with PBSC compared to days 16 and 15 in the patients receiving BM (P = .00063, .00014). The PBSC group required a median of 8 U of red blood cells and 24 U of platelets compared to 17 U of red blood cells and 118 U of platelets for BM transplant recipients (P = .0005, .0001). The estimated risks of developing grades 2 to 4 acute GVHD were 37% for the PBSC group and 56% for the BM group (P = .18), while the estimated risks of grades 3 to 4 acute GVHD were 14% for the PBSC group and 33% for the BM group, P = .05). Chronic GVHD occurred in 7 of 18 evaluable patients receiving PBSC and 6 of 23 evaluable patients receiving BM, P = .5. The estimated risks of transplant-related mortality at 200 days were 27% versus 45% (P = .33) relapse were 70% versus 53% (P = .27) and of overall survival were 50% and 41% (P = .39) for patients transplanted with PBSC or BM, respectively. This retrospective comparison suggests that compared to marrow transplantation from HLA-identical donors, allogeneic PBSC transplantation from HLA-identical donors is associated with faster engraftment, fewer transfusions, and no greater incidence of acute or chronic GVHD.

Adult↗

Histocompatibility testing of dog families with highly polymorphic microsatellite markers.

The dog has served traditionally as a model for marrow and organ transplantation. A key component of any study of transplantation is histocompatibility typing of donors and recipients. Towards the development of a less expensive, more simplified typing system within canine families, a new highly polymorphic microsatellite marker for the canine Major Histocompatibility Complex class II region was isolated and characterized. In addition, we report on the application of class I and class II microsatellite-based markers for following the inheritance of the alleles within the canine analog of the human HLA loci, DLA, through multi-generation pedigree.

Alleles↗

Canine CD34: cloning of the cDNA and evaluation of an antiserum to recombinant protein.

Increasingly, enriched populations of hematopoietic progenitors are used in experimental and clinical transplantation studies. The separation of progenitors is based on the expression of CD34, a marker preferentially expressed on progenitor cells. The dog model has been important for preclinical transplant studies, because it has proven predictive for outcomes in human hematopoietic stem cell transplantation. To identify and isolate canine hematopoietic progenitors, we have cloned a cDNA encoding a CD34 homologue from a canine myelomonocytic leukemia cell line, ML2. The CD34 homologue cDNA predicts an amino acid sequence that is highly conserved with human and murine CD34 in the cytoplasmic domain, transmembrane domain, and C-terminal end of the extracellular domain, but shows considerable divergence from these sequences at the amino-terminal end of the protein. In Western blotting studies, canine CD34 homologue (caCD34) appears to be a heavily and variably glycosylated protein with a molecular weight of approximately 100 kD and shows some tissue-specific differences in protein mass. To evaluate the expression of caCD34 protein, the extracellular domain of caCD34 was expressed as an Ig fusion protein and used as an immunogen to generate a rabbit polyclonal antiserum. The antiserum reacted against the fusion protein, against vascular endothelium, and with three leukemic cell lines. Approximately 1% of canine bone marrow cells stained brightly with antibodies to caCD34 and this population was 25- to 50-fold enriched for colony-forming units-granulocyte-macrophage as compared to unfractionated marrow mononuclear cells. These findings suggest that the canine CD34 homologue is expressed on bone marrow progenitor cells and, thus, that this molecule should be a valuable marker for identifying and isolating canine hematopoietic progenitors for experimental hematopoiesis and stem cell transplantation.

Amino Acid Sequence↗

Bone marrow transplantation for sickle cell disease.

BACKGROUND: We investigated the risks and benefits of allogeneic bone marrow transplantation in children with complications of sickle cell disease. METHODS: Twenty-two children less than 16 years of age who had symptomatic sickle cell disease received marrow allografts from HLA-identical siblings between September 1991 and April 1995. The indications for transplantation included a history of stroke (n = 12), recurrent acute chest syndrome (n = 5), and recurrent painful crises (n = 5). Patients were prepared for transplantation with busulfan, cyclophosphamide, and antithymocyte globulin. RESULTS: Twenty of the 22 patients survived, with a median follow-up of 23.9 months (range, 10.1 to 51.0), and 16 patients had stable engraftment of donor hematopoietic cells. In three patients the graft was rejected and sickle cell disease recurred; in a fourth patient graft rejection was accompanied by marrow aplasia. In 1 of the 16 patients with engraftment, there was stable mixed chimerism. Two patients died of central nervous system hemorrhage or graft-versus-host disease. Kaplan-Meier estimates of survival and event-free survival at four years were 91 percent and 73 percent, respectively. Among patients with a history of acute chest syndrome, lung function stabilized; among patients with prior central nervous system vasculopathy who had engraftment, stabilization of cerebrovascular disease was documented by magnetic resonance imaging. CONCLUSIONS: Allogeneic stem-cell transplantation can be curative in young patients with symptomatic sickle cell disease.

Adolescent↗