[Show abstract][Hide abstract] ABSTRACT: The lack of transplantable tumors has limited assessment of graft-versus-tumor effects following hematopoietic cell transplantation in clinically relevant large-animal models. We describe the derivation and characterization of porcine tumor cell lines with initial efforts of tumor transplantation using immunocompromised mice and highly inbred sublines of Massachusetts General Hospital major histocompatibility complex (MHC)-inbred miniature swine. Autopsies were performed routinely on swine that died unexpectedly or had suspicion of malignancy based on clinical symptoms or peripheral blood analysis. Tissue samples were obtained for pathology, phenotyped by flow cytometry, and placed in culture. Based on growth, lines were selected for passage into nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice and miniature swine. Porcine tumor recipients were preconditioned with total body irradiation from 0 to 500 cGy or with a 30-day course of oral cyclosporine. We identified 19 cases of hematologic tumors. Nine distinct tumor cell lines were established from 8 of these cases, including 3 derived from highly inbred sublines. In vivo tumor growth and serial transfer were observed in immunocompromised mice for one tumor cell line and in miniature swine for 1 of 2 tumor cell lines expanded for this purpose. These results suggest the possibility of developing a transplantable tumor model in this large-animal system.
[Show abstract][Hide abstract] ABSTRACT: Hematopoietic cell transplantation may offer the only cure for patients with hematological diseases. The clinical application of this therapy has been limited by toxic conditioning and lack of matched donors. Haploidentical transplantation would serve to extend the potential donor pool; however, transplantation across major histocompatibility complex barriers is often associated with severe graft-versus-host disease. Here we evaluate a novel protocol to achieve engraftment across mismatch barriers without toxic conditioning or significant posttransplant complications.
Nine major histocompatibility complex (MHC)-defined miniature swine received haploidentical hematopoietic cell transplantation following standard myeloablative conditioning. Nine additional animals received haploidentical hematopoietic cell transplantation following a minimally myelosuppressive regimen, consisting of 100 cGy total body irradiation, immunotoxin mediated T-cell depletion, and a short course of cyclosporine. Donor cell engraftment and peripheral chimerism was assessed by polymerase chain reaction and flow cytometry. Graft-versus-host disease was monitored by clinical grading and histology of skin biopsy specimens.
All animals conditioned for haploidentical hematopoietic cell transplantation using myeloablative conditioning were euthanized within 2 weeks due to engraftment failure or graft-versus-host disease. All animals conditioned with the nonmyeloablative regimen developed multilineage peripheral blood chimerism during the first 2 months following transplantation. Six animals evaluated beyond 100 days maintained multilineage chimerism in the peripheral blood and lymphoid tissues, showed evidence of progenitor cell engraftment in the bone marrow, and had minimal treatment-related complications.
Here we report that stable multilineage chimerism and engraftment can be established across haploidentical major histocompatibility complex barriers with minimal treatment-related toxicity and without significant risk of graft-versus-host disease.
[Show abstract][Hide abstract] ABSTRACT: In utero hematopoietic stem-cell transplantation has been shown to induce donor-specific tolerance in small-animal models. However, tolerance has been difficult to achieve in large-animal studies.
Outbred swine underwent in utero transplantation of fully major histocompatibility complex (MHC)-mismatched CD3-depleted bone marrow mixed with fresh bone marrow to achieve a final CD3 content of 1.5%. Transplantation was performed at 50 to 55 days' gestation and two animals survived long term and demonstrated multilineage peripheral blood hematopoietic chimerism. These two long-term survivors were analyzed for in vitro evidence of donor-specific tolerance by mixed leukocyte reaction (MLR), cell-mediated lysis (CML), and antibody testing and in vivo by kidney transplantation.
Both animals demonstrated in vitro donor-specific unresponsiveness by MLR and CML and did not demonstrate anti-donor antibody production. Donor matched kidney transplants were performed without immunosuppression and functioned for more than 100 days, with no evidence for rejection.
The authors demonstrate conclusively that in utero transplantation of fully MHC-mismatched bone marrow in swine can lead to engraftment and stable multilineage hematopoietic chimerism and tolerance to postnatal donor MHC-matched kidney transplantation without the need for immunosuppression.
[Show abstract][Hide abstract] ABSTRACT: Stable engraftment of hematopoietic progenitors and multilineage chimerism following in utero bone marrow transplantation could be a promising modality for treatment of prenatally diagnosed blood dyscrasias. For treatment of these diseases, stable chimerism in the myeloid and erythroid lineages is important because it is anticipated that donor-derived cells will compensate for defects in these host lineages. In the present study, a preparation of bone marrow that includes fresh, unmanipulated marrow mixed with T-cell-depleted marrow to achieve 1.5% T-cell content, was injected into the intrahepatic portion of the umbilical vein of porcine fetuses at mid-gestation. Donor hematopoietic progenitor cell engraftment was assessed in fetal liver and recipient bone marrow postnatally by donor-specific polymerase chain reaction of colony-forming units. Chimerism was assessed in lymphoid tissues and peripheral blood by flow cytometry. Graft-versus-host disease (GVHD) was assessed by histological analysis of biopsies of skin, bone marrow, liver, and intestine. In this report, we demonstrate that stable multilineage chimerism across a full major histocompatibility complex disparity can be achieved without GVHD through in utero bone marrow transplantation.
No preview · Article · Apr 2005 · Experimental Hematology