Clinical responses to bone marrow transplantation in children with severe osteogenesis imperfecta.

Preclinical models have shown that transplantation of marrow mesenchymal cells has the potential to correct inherited disorders of bone, cartilage, and muscle. The report describes clinical responses of the first children to undergo allogeneic bone marrow transplantation (BMT) for severe osteogenesis imperfecta (OI), a genetic disorder characterized by defective type I collagen, osteopenia, bone fragility, severe bony deformities, and growth retardation. Five children with severe OI were enrolled in a study of BMT from human leukocyte antigen (HLA)-compatible sibling donors.

Defects in TCIRG1 subunit of the vacuolar proton pump are responsible for a subset of human autosomal recessive osteopetrosis.

Osteopetrosis includes a group of inherited diseases in which inadequate bone resorption is caused by osteoclast dysfunction. Although molecular defects have been described for many animal models of osteopetrosis, the gene responsible for most cases of the severe human form of the disease (infantile malignant osteopetrosis) is unknown. Infantile malignant autosomal recessive osteopetrosis (MIM 259700) is a severe bone disease with a fatal outcome, generally within the first decade of life.

A prospective randomized trial of the anti-emetic efficacy of ondansetron and granisetron during bone marrow transplantation.

To determine the comparative anti-emetic efficacy of ondansetron and granisetron in patients undergoing bone marrow transplantation, we performed a double-blind, randomized trial in pediatric and adult patients receiving transplants at the University of Minnesota. The results in 187 patients stratified by age (<18 years, n = 51; > or =18 years, n = 136) were analyzed. The average number of emetic episodes in the entire group from day -7 to 2 was 0.

Flt3 ligand antitumor activity in a murine breast cancer model: a comparison with granulocyte-macrophage colony-stimulating factor and a potential mechanism of action.

We have shown that Flk2/Flt3 ligand (Flt3L)-transduced tumor vaccine induces transferable T cell protection against a murine breast cancer cell line, but a direct comparison with the potent effector GM-CSF, the activity against preestablished tumors, and the mechanism of antitumor response in this breast cancer model are not known. We compared vaccination with C3L5 cells expressing Flt3L (C3Lt-Flt3L) and GM-CSF (C3L5-GMCSF) by injecting 1 x 10(4) cells subcutaneously into the chest wall and then, after 4 weeks, challenging the contralateral chest of tumor-free mice with parental C3L5 cells. C3L5-Flt3L and C3L5-GMCSF had reduced in vivo growth rates (25% tumor formation each) compared with 100% tumor formation of C3L5 cells expressing only neomycin phosphotransferase (C3L5-G1N).

Transplantability and therapeutic effects of bone marrow-derived mesenchymal cells in children with osteogenesis imperfecta.

In principle, transplantation of mesenchymal progenitor cells would attenuate or possibly correct genetic disorders of bone, cartilage and muscle, but clinical support for this concept is lacking. Here we describe the initial results of allogeneic bone marrow transplantation in three children with osteogenesis imperfecta, a genetic disorder in which osteoblasts produce defective type I collagen, leading to osteopenia, multiple fractures, severe bony deformities and considerably shortened stature. Three months after osteoblast engraftment (1.

Hematopoietic stem cell transplantation for infantile osteopetrosis.

Infantile osteopetrosis is a lethal disorder resulting from a severe defect in the ability of osteoclasts to resorb bone. The only therapy shown to be capable of providing lasting benefit is allogeneic hematopoietic stem cell transplantation (HCT). We report the outcome of 10 patients with infantile malignant osteopetrosis treated with HCT from an HLA A, B, DRB1 matched (n=6) or A or B locus mismatched (n=4) family member or unrelated donor at the University of Minnesota between 1978 and 1997.

Haemopoietic cell transplantation in children with juvenile myelomonocytic leukaemia.

Seven children, 11 months to 5.9 years of age, with juvenile myelomonocytic leukaemia (JMML) underwent allogeneic haemopoietic cell transplantation (HCT) using related or unrelated donor bone marrow or umbilical cord blood. All patients had active disease at time of transplant despite chemotherapy in five patients and chemotherapy and splenectomy in one patient prior to HCT conditioning.

Graft-versus-leukemia is sufficient to induce remission in juvenile myelomonocytic leukemia.

It has been unclear whether a graft-versus-leukemia (GVL) effect assists in the control of juvenile myelomonocytic leukemia (JMML) following allogeneic bone marrow transplant. We describe a patient with JMML who relapsed early after an unrelated donor transplant, and following withdrawal of immunosuppression developed graft-versus-host disease (GVHD). Associated with GVHD the proportion of donor cells measured by variable nucleotide tandem repeat (VNTR) analysis increased, and peripheral blasts and cutaneous disease were eliminated.

Endogenous IL-2 production by natural killer cells maintains cytotoxic and proliferative capacity following retroviral-mediated gene transfer.

Interleukin (IL)-2 therapy given at tolerable doses is insufficient to induce maximum activation of natural killer (NK) cells. We recently demonstrated that NK cells expanded in vivo can be maximally activated by short-term ex vivo incubation with 1000 U/mL IL-2. However, IL-2 withdrawal, which would occur with reinfusion, may lead to a rapid loss of cell viability and function.

The role of B7 costimulation by murine acute myeloid leukemia in the generation and function of a CD8+ T-cell line with potent in vivo graft-versus-leukemia properties.

Relapse is more frequent after autologous than allogeneic bone marrow transplantation (BMT), due in part to lack of T-lymphocyte mediated allogeneic graft-versus-leukemia (GVL) effects. Infusions of leukemia-reactive T cells to patients after autologous BMT may be a means for providing a GVL effect. Costimulation of T cells by binding of the CD28 receptor on T cells with B7-counter receptors on antigen presenting cells amplifies antigen-specific T-cell responses.

Unrelated donor bone marrow transplantation for children and adolescents with aplastic anaemia or myelodysplasia.

Allogeneic transplantation from an HLA-matched family member has been shown to be effective in reconstituting normal haemopoiesis in young people with severe cytopenias, classified as myelodysplastic syndrome (MDS) or severe aplastic anaemia (SAA). Unrelated donor transplant is a therapeutic choice for patients without a suitable family member donor. We report the outcome of seven patients < 20 years old with SAA and 10 with MDS treated with BMT from an HLA A,B DRB1 matched (n = 8) or A or B locus mismatched (n = 9) unrelated donor at the University of Minnesota between March 1988 and August 1995.

Unrelated donor bone marrow transplantation for children with acute leukemia.

Purpose: To test the use of unrelated donor bone marrow transplantation (URD BMT) to cure children with high-risk acute leukemias.

Patients And Methods: Between June 1985 and December 1994, 50 children with acute leukemia (15 acute myelogenous leukemia [AML], 35 acute lymphoblastic leukemia [ALL]; 22 greater than second complete remission [CR]) received BMT from a URD at the University of Minnesota. Ages ranged from 0.

Defective lymphocyte glycosidases in the macrophage activation cascade of juvenile osteopetrosis.

Generation of macrophage-activating factor requires a precursor protein, Gc protein (serum vitamin D3-binding protein), as well as participation of beta-galactosidase of inflammation-primed B lymphocytes and sialidase of T lymphocytes. The treatment of human peripheral blood mononuclear cells with an inflammatory lysophospholipid induced beta-galactosidase and sialidase activity of lymphocytes, leading to the generation of macrophage-activating factor and activation of monocytes/macrophages. However, lysophospholipid treatment of peripheral blood mononuclear cells from three infantile patients with osteopetrosis resulted in no significant activation of monocytes/macrophages.

Unrelated donor bone marrow transplantation for acute leukemia in patients with Down's syndrome.

The incidence of hematologic disorders in patients with Down's syndrome (DS) is significantly increased, and includes neonatal transient abnormal myelopoiesis and acute leukemias. Treatment of children with DS and leukemia has been controversial because of toxicity and associated congenital cardiac and other abnormalities. The role of BMT, particularly from an unrelated donor (URD), remains undefined in this population.

Interleukin-2 secretion by transduced and unselected BDL-2 lymphoma results in increased survival in mice with previously established disseminated disease.

The transfer and expression of cytokine genes into malignant cells to provide a more effective tumor response has shown promise. The majority of murine models in which tumor vaccination strategies have been tested have utilized selected and expanded clones of tumor cells, which is impractical clinically. In a model of murine B lineage lymphoma (BDL-2), we compared the effectiveness of tumor vaccines composed of a) a BDL-2 clone established by G-418 resistance following transduction with the LIL2SN retrovirus and screened for maximal IL-2 secretion, b) a syngeneic fibroblast line transduced with LIL2SN and screened for G-418 resistance and IL-2 expression, which was co-injected with the parental line, and c) a heterogeneous (unselected) population of BDL-2 cells transduced with the MFG/IL2 virus, reported to provide enhanced expression of cytokine genes and minimize the need for selection.

Irradiation of singly and doubly transduced murine neuroblastoma cells expressing B7-1 and producing interferon-gamma reduces their capacity to induce systemic immunity.

We have previously reported that immunization with low major histocompatibility complex (MHC) class I expressing murine neuroblastoma (neuro-2a) transduced with B7-1 fails to induce significant protection to wild-type tumor challenge. In this study we investigated whether B7-1 expressing neuro-2a cells can stimulate an effective T-cell response if they were cotransduced with the interferon-gamma (IFN-gamma) gene to upregulate MHC class I. Transfer of both the IFN-gamma and B7-1 genes into neuro-2a (N-2a/B7-1/IFN) almost completely abrogated the tumorigenic potential of this tumor and improved survival when compared with mice receiving the single transductants, N-2a/IFN and N-2a/B7-1.

Clinical importance of pre-morteum blood lymphocytes in cadaver donor tissue typing.

We have refined our immunomagnetic bead (IM bead) procedures to isolate pure and viable lymphocyte subpopulation from pre-morteum (PM) blood for cadaver donor HLA typing, preliminary and final crossmatches (XMs). The results of 1220 XMs were compared using T/B lymphocytes isolated either from PM blood or spleen/lymphnode (SPLN) tissue. IM bead technique was used to isolate T/B cells from PM blood and nylon wool column (NWC) technique was used to isolate T/B cells from SPLN.

Dependency on intercellular adhesion molecule recognition and local interleukin-2 provision in generation of an in vivo CD8+ T-cell immune response to murine myeloid leukemia.

The immune response to a murine myeloid leukemia (cell line C1498) was studied in vitro and in vivo. Natural killer (NK) cells and CD8+ cytotoxic T lymphocytes (CTL) were shown to lyse C1498 in vitro through the binding of leukocyte function antigen-1 (LFA-1) on effectors and intercellular adhesion molecule-1 (ICAM-1) and ICAM-2 on C1498 target cells. However, the ability of nonimmunized mice to resist an in vivo challenge of a low dose (10(4)) of C1498 was NK-cell, but not T-cell dependent.

B7-1 expression decreases tumorigenicity and induces partial systemic immunity to murine neuroblastoma deficient in major histocompatibility complex and costimulatory molecules.

Neuroblastoma may escape an immune attack by virtue of its low expression of surface accessory molecules essential in the antitumor response. Murine neuroblastoma, neuro-2a, was transduced with the retroviral vector LB7-1SN to examine the influence of B7-1 expression on the immune response directed against a low major histocompatibility class (MHC) I and class II negative, B7-2, and ICAM-1 negative tumor. Using a retroperitoneal model for implantation of neuroblastoma in its natural site, we demonstrated that expression of B7-1 by neuro-2a reduces its tumorigenicity.

Interleukin-2 gene transfer into murine neuroblastoma decreases tumorigenicity and enhances systemic immunity causing regression of preestablished retroperitoneal tumors.

Murine neuroblastoma, neuro-2a, was transduced with the retroviral vector LIL-2SN in order to examine the influence of localized interleukin (IL)-2 production on the immune response against a low major histocompatibility complex (MHC) class I, class II-negative, and intercellular adhesion molecule (ICAM)-1-negative tumor. Two neomycin-resistant (neo R) clones, N-2a/IL-2/L (2.5 +/- 0.

Transfection of the mouse ICAM-1 gene into murine neuroblastoma enhances susceptibility to lysis, reduces in vivo tumorigenicity and decreases ICAM-2-dependent killing.

We determined the expression of intercellular adhesion molecules (ICAM) on neuro-2a cells in order to evaluate whether they were involved in cytolysis of murine neuroblastoma. Fluorescence-activated cell sorting analysis revealed that the control neomycin-resistance-gene-transduced line (neuro-2a/LN) had poor expression of ICAM-1 (mean channel fluorescence, MCF = 3.7).

Retroviral-mediated transfer of the murine interleukin-3 gene engineered for intracellular retention results in a myeloproliferative syndrome but is associated with circulating interleukin-3 levels.

Myeloid leukemias have been shown to secrete as well as respond to cytokines such as interleukin-3 (IL-3) with an increased growth rate and may therefore become self-stimulatory through an external autocrine mechanism. In vitro evidence that IL-3 is functional within the intracellular compartment has been obtained through modification of the murine IL-3 gene to encode for the amino acids SEKDEL on the carboxyl terminus of the protein, resulting in preferential intracellular retention. The ability of bone marrow-derived hematopoietic progenitor cells to increase their proliferative capacity through intracellular mechanisms was investigated in vivo using retroviruses containing the wild-type or SEKDEL-modified IL-3 gene, transcriptionally regulated by the retroviral long terminal repeat (LTR) or by the SV40 early promoter, in lethally irradiated, bone marrow-reconstituted mice.