C.F. LeMaistre

Ex-vivo expansion of bone marrow progenitor cells for hematopoietic reconstitution following high-dose chemotherapy for breast cancer

The use of hematopoietic growth factors, stromal monolayers, and frequent medium exchange allows the expansion of hematopoietic progenitors ex-vivo. We evaluated the use of ex-vivo expanded progenitor cells for hematopoietic reconstitution following high dose chemotherapy (HDC) in breast cancer patients. Patients with high-risk Stage II or metastatic breast carcinoma underwent bone marrow aspirations using general anesthesia. A total of 675-1125 x 10(6) mononuclear cells (MNC) were seeded for ex-vivo expansion for 12 days in controlled perfusion bioreactors (Aastrom Biosciences, Inc.). The bone marrow cultures, which included the stromal cells collected with the aspirate, were supplemented with erythropoietin, granulocyte-macrophage-colony stimulating factor (GM-CSF)/IL-3 fusion protein (PIXY 321), and flt3 ligand. Stem cell transplant was performed with expanded cells after HDC. A median bone marrow volume of 52.9 mL (range 42-187 mL) was needed to inoculate the bioreactors. Median fold expansion of nucleated cells (NC) and colony forming unit granulocyte-macrophage (CFU-GM) was 4.9 and 9.5, respectively. The median fold expansion of CD34+lin- and long-term culture-initiating culture (LTC-IC) was 0.42 and 0.32, respectively. Five patients were transplanted with ex-vivo expanded NC. Median days to an absolute neutrophil count > 500/microL was 18 (range 15-22). Median days to a platelet count > 20,000/microl was 23 (range 19-39). All patients had sustained engraftment of both neutrophils and platelets. Immune reconstitution was similar to that seen after HDC and conventional stem cell transplantation. We conclude that ex-vivo expansion of progenitor cells from perfusion cultures of small volume bone marrow aspirates, allows hematopoietic reconstitution after HDC.

Granulocyte Colony‐Stimulating Factor Mobilizes More Dendritic Cell Subsets Than Granulocyte‐Macrophage Colony‐Stimulating Factor with No Polarization of Dendritic Cell Subsets in Normal Donors

Dendritic cells (DCs) are effective antigen‐presenting cells. We hypothesized that increasing the DC populations in donor lymphocyte infusions (DLIs) may augment the graft versus malignancy effect, particularly if granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) mobilization resulted in increased precursor dendritic cell (pDC) 1 cells. Mature DCs, pDC1 cells, pDC2 cells, and CD34+ cells from the same donor were compared after granulocyte colony‐stimulating factor (G‐CSF) mobilized peripheral blood stem cell collections and GM‐CSF mobilized DLI collections. Mobilization with G‐CSF resulted in up to a 10‐fold larger number of CD34+ cells per kg and a 3–5‐fold larger number of mature DCs, pDC1 cells, and pDC2 cells within the same donor compared with GM‐CSF. The ratio of pDC1 to pDC2 in each donor remained constant with either cytokine. In this small sample of normal donors, it appears that G‐CSF mobilizes more CD34+ cells, mature DCs, pDC1 cells, and pDC2 cells within the same donor than does GM‐CSF, with no significant polarization by G‐CSF or GM‐CSF for either pDC1 or pDC2 cells.

Once daily busulfan cyclophosphamide is well tolerated and effective as a preparative regimen for allogeneic hematopoietic stem cell transplant

We report a retrospective review of our institutional data using once daily intravenous (IV) busulfan (Bu) and cyclophosphamide (Cy) and total body irradiation (TBI)/Cy in patients who received allogeneic hematopoietic stem cell transplant (HCT) from January 2000 to December 2006. Bu 3.2u2009mg/kg IV once dailyu2009×u20094 days followed by Cy 60u2009mg/kg IV dailyu2009×u20092 days was given to 42 patients. Cy 60u2009mg/kg IV daily for 2 days and fractionated TBI 1200 cGy delivered over 3 days was given to 60 patients. Veno-occlusive disease developed in two patients in the once daily BuCy group and no patients in the TBI/Cy group. The once daily BuCy group had significantly less transplant-related mortality (TRM) than the TBI/Cy group at 100 days (pu2009=u20090.047) and better overall survival at 1 year (pu2009=u20090.01). This review demonstrates once daily IV BuCy and allogeneic HCT is well tolerated with no unexpected TRM or differences in clinical outcomes.

Empirical criteria for the selection of quality-of-life instruments for the evaluation of peripheral blood progenitor cell transplantation

We propose a method for selecting quality-of-life instruments for use in phase III trials using the convergent validity of patient responses collected in phase I and II clinical trials. Two generic and two disease-specific instruments were administered to patients with breast cancer undergoing peripheral blood progenitor cell mobilization and transplantation. They included the visual analog scale from the EuroQoL EQ5D instrument, the SF-36, the European Organization for Research and Treatment of Cancer (EORTC)-QLQ-C30, and the Functional Assessment of Cancer Therapy instrument. No single instrument was found to have superior convergent validity in all domains, but the EORTC-QLQ-C30 seemed to perform better than the SF-36.

Ex Vivo-Expanded Hematopoietic Cell Graft Recipients Exhibit T Cell Repertoire Diversity Similar to That Seen After Conventional Stem Cell Transplants

The feasibility of using ex vivo-expanded hematopoietic progenitor cells to reconstitute hematopoiesis after high-dose chemotherapy is presently being examined. Early studies have shown that myeloid and erythroid hematopoiesis can be successfully reconstituted after high-dose chemotherapy and ex vivo-expanded hematopoietic cell transplantation. The lymphoid reconstitution, however, has not been addressed previously. In this study, we examined the diversity of the T cell receptor V beta chain (TCRBV) repertoires in 5 breast cancer patients who were transplanted with ex vivo-expanded bone marrow mononuclear cells as the only source of hematopoietic graft. Using the TCRBV third complementarity determining region (CDR3) fingerprinting methodology, it is shown that CD4(+) and CD8(+) T cell subsets after ex vivo-expanded hematopoietic cell graft transplants exhibit TCRBV diversities that are similar in complexity when compared to those seen after conventional autologous peripheral blood stem cell transplants (PBSCT). No apparent difference in the extent of CDR3 diversity was found between ex vivo expanded and conventional autologous PBSCT recipients when the CD4(+) and CD8(+) subsets were further separated into CD45RA(+) naïve and CD45RO(+) memory subsets. The diversity of the CD45RA(+) naïve subsets was as complex as that of the CD45RO(+) memory subsets. These results indicate that T cell repertoire diversification is not further compromised when ex vivo-expanded hematopoietic cells are used instead of autologous peripheral blood stem cells as the only source of graft.

Phase I and pharmacokinetic study of once-daily dosing of intravenously administered busulfan in the setting of a reduced-intensity preparative regimen and allogeneic hematopoietic stem cell transplantation as immunotherapy for renal cell carcinoma.

We performed a Phase I and pharmacokinetic study of once-daily, intravenously administered busulfan in the setting of a reduced-intensity preparative regimen and matched sibling donor allogeneic stem cell transplantation for treatment of metastatic renal cell carcinoma. Seven male patients with metastatic renal cell carcinoma received intravenously administered busulfan at 3.2 mg/kg once daily on day -10 and day -9, fludarabine at 30 mg/m2 on day -7 through day -2, and equine antithymocyte globulin at 15 mg/kg per day on day -5 through day -2. The mean area under the plasma concentration-time curve (AUC) and the half-life of the first dose of intravenously administered busulfan were 6,253 microM x minute (range, 5,036-7,482 microM x minute) and 3.37 hours (range, 2.54-4.00 hours), respectively. The AUC was higher than predicted from extrapolation of AUC data for the same total dose of intravenously administered busulfan divided into four doses daily. Patients experienced greater than expected regimen-related toxicity for a reduced-intensity preparative regimen, and the study was stopped. In conclusion, this preparative regimen was associated with unacceptable regimen-related toxicity among patients with metastatic renal cell carcinoma.