Jared Klein

Transplantation of highly purified CD34+Thy-1+ hematopoietic stem cells in patients with metastatic breast cancer.

We report here the transplantation of extensively purified mobilized peripheral blood CD34Thy-1 hematopoietic stem cells from 22 patients with recurrent or metastatic breast cancer. Patients were mobilized with either high-dose granulocyte colony-stimulating factor (G-CSF) alone or cyclophosphamide plus G-CSE Median purity of the stem cell product at cryopreservation was 95.3% (range, 91.1%-98.3%), and viability was 98.6% (range, 96.5%-100%). After high-dose chemotherapy with carmustine, cisplatin, and cyclophosphamide, CD34+Thy-1 cells at a median dose of 11.3 x 10(5) per kilogram (range, 4.7-163 x 10(5) per kilogram) were infused. No infusion-related toxicity was observed. Neutrophil recovery was prompt, with median absolute neutrophil count >500/microL by day 10 (range, 8-15 days) and >1000/microL by day 11 (range, 8-17 days). Median platelet recovery (>20,000/microL) was observed by day 14 (range, 9-42 days) and >50,000/microL by day 17 (range, 11-49 days). Tumor cell depletion below the limits of detection of a sensitive immunofluorescence-based assay was accomplished in all patients who had detectable tumor cells in apheresis products before processing. Although CD4+ T-cell reconstitution was slow, no unusual infections were observed. Neither early nor late graft failure was observed, and no patient required infusion of unmanipulated backup cells. At a median follow-up of approximately 1.4 years and a maximum follow-up of 2.5 years, 16 of the 22 patients remain alive, with 9 free of disease progression, and have stable blood counts. In summary, highly purified CD34+Thy-1+ cells used as the sole source of the hematopoietic graft result in rapid and sustained hematopoietic engraftment.

Dendritic cells generated from CD34+ progenitor cells with flt3 ligand, c-Kit ligand, GM-CSF, IL-4, and TNF-α are functional antigen-presenting cells resembling mature monocyte-derived dendritic cells

Dendritic cells (DCs) are powerful antigen-presenting cells. Because DCs are rare cells, methods to produce them in vitro are valuable ways to study their biologic properties and to generate cells for immunotherapy. This study defines the antigen-presenting properties of DCs generated in vitro from CD34+ cells of patients with breast cancer. The combination of cytokines flt3 ligand + c-kit ligand + granulocyte-macrophage colony-stimulating factor (GM-CSF) + interleukin-4 (IL-4) + tumor necrosis factor-alpha (TNF-alpha) was used to maximize the output of mature DCs in the culture of CD34+ cells while minimizing the production of monocytes. Cells grew and differentiated into DCs as measured by a time-dependent upregulation of cell surface antigens major histocompatibility complex class II, CD1a, CD80, CD86, CD40, and CD4, so that 40% +/- 9% (n = 6) of cells in culture at day 15 were CD1a+CD14-. Markers were acquired in the same sequence as on monocytes induced to differentiate with GM-CSF + IL-4. Differentiation was marked by a time-dependent increase in allostimulatory function, which, at its peak, was more potent than in cultures of DCs generated from monocytes with GM-CSF + IL-4, but was comparable on a cell-to-cell basis to that of mature monocytes cultured in flt3-ligand + c-kit-ligand + GM-CSF + IL-4 + TNF-alpha. Both CD34+ cell-derived and monocyte-derived DCs were able to process and to present tetanus toxoid and keyhole limpet hemocyanin to autologous T cells and to present major histocompatibility class I-binding peptides to CD8+ cytotoxic T lymphocytes inducing interferon-gamma production. Altogether, these results suggest that DCs generated from CD34+ cells of patients with breast cancer with flt3 ligand, c-kit ligand, GM-CSF, IL-4, and TNF-alpha are competent antigen-presenting cells, particularly for CD8+ cytotoxic T lymphocytes, and resemble mature monocyte-derived DCs in the assays described here.

Successful allogeneic bone marrow transplantation in selected patients over 50 years of age – a single institution’s experience

As allogeneic bone marrow transplantation (BMT) is a procedure with a higher risk of morbidity and mortality in older patients, many institutions place a limit of 50 to 55 years for allogeneic BMT. Consequently, older patients may not be offered potentially curative treatment for otherwise poor prognosis diseases such as AML or myelodysplastic syndrome. We compared the outcome of 59 patients aged over 50, 124 aged 40–50, and 253 aged 18–39 years who underwent allogeneic BMT in our institution between August 1987 and April 1996. Our results show little influence of age on outcome when comparing patients over 50 years with patients 40–50 years. Apart from an initial higher transplant mortality rate, overall survival was not significantly different between the three age groups. The 1-year and 2-year overall survival rates were 57% and 48%, 57% and 48%, and 62% and 58% for the >50 years, 40–50 years, and <40 years patients, respectively. the incidence of gvhd was also comparable. we conclude that allogeneic bmt can be performed in selected patients over the age of 50 years with acceptable morbidity and mortality and that older patients should not be denied this treatment based on age alone.

Recovery of lymphocyte and dendritic cell subsets after autologous CD34+ cell transplantation

Following high-dose chemotherapy (HDC) and peripheral blood progenitor cell transplantation (PBPCT), there are profound changes in leukocyte homeostasis and the immune system is compromised. Transplantation of purified CD34+ cells may further compromise immune recovery because the grafts are depleted of mature immune cells. However, a detailed monitoring of immune cell reconstitution has not been done. We monitored blood levels of antigen-presenting cells (APC) and of lymphocytes by multi-color flow cytometry at different times post CD34+ PBPCT. We found a rapid normalization of circulating levels of the antigen-presenting CD11c+ dendritic cells (defined as lineage− HLA-DR+ CD11c+ cells). There was a slight over-representation of lin− DR+ CD11c− cells at day 42 post transplantation suggesting that the composition of the APC population might be affected. Normal levels of total T, B and NK lymphocytes were rapidly achieved but the composition of the T cell population was abnormal. Patients had elevated levels of CD8+ T cells at early times and a persistent reduction in levels of naive CD8+ T cells (CD8+ CD4− CD45RA+ CD27+) and of naive CD4+ T cells (CD4+CD3+ CD8− CD45RA+). Thus, we found a rapid recovery of DC after CD34+ PBPCT but the specific numerical defects in naive T cells are likely to be a major cause of immune dysfunction in the patients. Bone Marrow Transplantation (2000) 25, 1249–1255.

Long-term outcome of patients with metastatic breast cancer treated with high-dose chemotherapy and transplantation of purified autologous hematopoietic stem cells.

Metastatic breast cancer remains a major treatment challenge. The use of high-dose chemotherapy (HDCT) with rescue by autologous mobilized peripheral blood (MPB) is controversial, in part because of contamination of MPB by circulating tumor cells. CD34(+)Thy-1(+) selected hematopoietic stem cells (HSC) represent a graft source with a greater than 250,000-fold reduction in cancer cells. Here, we present the long-term outcome of a pilot study to determine feasibility and engraftment using HDCT and purified HSC in patients with metastatic breast cancer. Twenty-two patients who had been treated with standard chemotherapy were enrolled into a phase I/II trial between December 1996 and February 1998, and underwent HDCT followed by rescue with CD34(+)Thy-1(+) HSC isolated from autologous MPB. More than 12 years after the end of the study, 23% (5 of 22) of HSC recipients are alive, and 18% (4 of 22) are free of recurrence with normal hematopoietic function. Median progression-free survival (PFS) was 16 months, and median overall survival (OS) was 60 months. Retrospective comparison with 74 patients transplanted between February 1995 and June 1999 with the identical HDCT regimen but rescue with unmanipulated MPB indicated that 9% of patients are alive, and 7% are without disease. Median PFS was 10 months, and median OS was 28 months. In conclusion, cancer-depleted HSC following HDCT resulted in better than expected 12- to 14-year PFS and OS in a cohort of metastatic breast cancer patients. These data prompt us to look once again at purified HSC transplantation in a protocol powered to test for efficacy in advanced-stage breast cancer patients.

Early intervention with antithrombin III therapy to prevent progression of hepatic venoocclusive disease

Venoocclusive disease (VOD) is the most frequent cause of early nonrelapse mortality among patients receiving high-dose chemoradiotherapy and hematopoietic stem cell transplantation. Endothelial injury of sinusoids and hepatic veins following chemotherapy is considered the initial event in the development of VOD. Activation of the coagulation cascade and inflammatory processes following endothelial injury results in a hypercoagulable state and a localized consumption of the natural anticoagulants, antithrombin III, protein C and protein S. The resultant coagulopathy can lead to multiorgan dysfunction and death. The objective was to retrospectively study the largest series of patients that has received antithrombin III for the treatment of VOD following hematopoietic stem cell transplantation. A total of 48 patients were diagnosed with VOD post hematopoietic stem cell transplantation (median age, 39 years; range, 1–69 years); 38 of the 48 received a nonradiation-based conditioning regimen and 21 of 48 received a transplant from an unrelated donor. Treatment was primarily directed at early intervention rather than prophylactic therapy to correct the antithrombin III deficiency associated with VOD. We attempted to achieve antithrombin III levels greater than 120%. There was no significant treatment-related morbidity. The overall 100-day mortality for the treatment cohort was 17%, with 10% for the mild/moderate group and 39% for the severe group, respectively. In conclusion, the encouraging results of this study suggest that this antithrombin III treatment should be further considered in patients with severe VOD.

Safety of low-dose low-molecular-weight-heparins in thrombocytopenic stem cell transplantation patients: A case series and review of the literature

Summary:Few attempts have been made to examine the feasibility of safely administering low-molecular-weight-heparins (LMWHs) in the presence of concurrent thrombocytopenia. We retrospectively investigated the safety of low-dose LMWH in BMT patients, a population at risk of bleeding. In total, 26 patients received at least one dose of low-dose enoxaparin (ie <1u2009mg/kg/day) during thrombocytopenia. s.c. enoxaparin 40u2009mg once daily was given in 85% of the cohort. The mean number of platelet days <55 × 109 and <20 × 109/l were 16.5 days (95% CI=8.04–24.96) and 4.14 days (95% CI=2.35–5.93), respectively. The mean number of low-dose enoxaparin administration days when platelet <55 × 109 and 20 × 109/l were 9.89 days (95% CI=3.26–16.53) and 2.25 days (95% CI=0.57–3.93), respectively. Minor bleeding occurred in four patients (15%) whereas major episodes developed in two patients (8%). The latter two events occurred during the transition between full therapeutic (ie 1.5–2u2009mg/kg/day) and low-dose enoxaparin close to the onset of thrombocytopenia. The present case series, along with the discussed literature, descriptively suggests that low-dose enoxaparin may be safely administered at a platelet count in the range of 20 and 55 × 109/l in BMT patients who weigh >55u2009kg.

High-dose Chemotherapy and Adoptive Immunotherapy in the Treatment of Recurrent Pediatric Brain Tumors

Pediatric patients with recurrent brain tumors have a poor prognosis and limited therapeutic options. We investigated the use of high-dose chemotherapy with adoptive immunotherapy for recurrent brain tumors. Three pediatric patients with recurrent brain tumors received high-dose chemotherapy. This was followed by adoptive transfer of ex-vivo expanded T-cells. The T-cells were generated from peripheral blood after immunization with autologous cancer cells. The objectives of this study included (1) establishing the safety and feasibility of this potential treatment, (2) measuring changes in immune response after high-dose chemotherapy and adoptive immunotherapy, and (3) determining whether adoptive immunotherapy would be able to translate into a clinical response. Immune function was tested in all patients at the time of enrollment into the study. Humoral responses to recall antigens delayed-type hypersensitivity (DTH) were intact in all patients. After immunizing patients with autologous cancer cells, peripheral blood lymphocytes were harvested and activated with anti-CD3, expanded in-vitro, and infused post-autologous transplant. Patients received at least three doses of the vaccine, each consisting of an intradermal administration near a draining lymph node at biweekly intervals. Toxicity was limited and well tolerated in all patients. All three patients showed a tumor-specific immune response by serial imaging. Responses were durable at 16, 23, and 48 months, respectively.

High Fatality Rate of Epstein-Barr Virus-Associated Lymphoproliferative Disorder Occurring after Bone Marrow Transplantation with Rabbit Antithymocyte Globulin Conditioning Regimens

ABSTRACT Epstein-Barr virus (EBV)-associated lymphoproliferative disorder (EBV-LPD) following bone marrow transplantation can be fatal. The major risk factors for the development of EBV-LPD are ex vivo T-cell depletion or in vivo T-cell depletion with either antithymocyte globulin (ATG) or monoclonal anti-T-cell antibodies. Between March 1999 and January 2001, a total of 23 transplants with ATG of equine source (20 transplants) and ATG of rabbit source (3 transplants) used as part of the preparatory regimen were performed at the Barbara Ann Karmanos Cancer Institute in Detroit, Mich. The three patients who received rabbit ATG developed EBV-LPD between 60 and 90 days following bone marrow transplantation. However, there were no cases of EBV-LPD in the equine group. Treatment given in these cases consisted of tapering immunosuppression, antiviral therapy, unprocessed donor lymphocyte infusion, mobilized peripheral blood progenitor cell rescue infusion (one patient), and chemotherapy (one patient). All three patients died of complications from EBV-LPD. The association of rabbit ATG with the development of EBV-LPD suggests that patients receiving rabbit ATG as part of their preparatory regimens require close monitoring of the EBV viral load and possible early intervention with antiviral therapy.

Low Infectious Morbidity after Intensive Chemotherapy and Autologous Peripheral Blood Progenitor Cell Transplantation in the Outpatient Setting for Women with Breast Cancer

Autologous peripheral blood progenitor cell (PBPC) transplantation is increasingly employed in the outpatient setting, yet data on early complications following PBPC transplantation are scant. We evaluated 105 women with high-risk primary or metastatic breast cancer who were treated at a single institution during 1996--1997. The mean duration of neutropenia (absolute neutrophil count, <500 cells/mm(3)) was 7.5 days. Twenty-nine percent of women remained afebrile throughout the neutropenic period. Of the remaining 71%, most (64 of 75) had fever of unknown origin. Infections, mostly of mild severity, occurred in 34% of women; these infections included bacteremia due to gram-positive organisms, catheter site infection, cellulitis, pneumonia, oral candidiasis, herpes simplex virus infection, and vaginitis. Fifty percent of PBPC transplant recipients required hospital admission, usually because of persistent fever; the mean duration of hospitalization was 3 days. No deaths or serious adverse events occurred. Such reduced infectious morbidity may be a consequence of minimal oral and/or gastrointestinal mucositis associated with the conditioning regimen and broad-spectrum antimicrobial prophylaxis used for this patient population.