Myoblast transfer of human erythropoietin gene in a mouse model of renal failure.

Abstract

Key words: gene therapy * anemia * renal failure * muscle cell transplantation * nude mouse Anemia is an invariable consequence of end-stage renal failure (ESRF) and recombinant erythropoietin has dramatically improved the quality of life of patients with ESRF.As an alternative approach, we developed a myoblast gene transfer system for the systemic delivery of human erythropoietin (EPO). We recently reported that transplantation of 4 x 107 cells of a C2 myoblast cell clone that stably secretes high level of functional human EPO, increased hematocrit from 44.6±3.0 to 71.2±7.9(%) in 2 wk, and the increase was sustained for at least 12 wk in nude mice. A renal failure model was created by a two-step nephrectomy in nude mice, and myoblasts were transplanted 3 wk after the second nephrectomy, when mean blood urea nitrogen level had increased from 26.3±6.1 to 85.4±24.0 (mg/ dl) and the hematocrit had decreased from 45.2±2.7 to 33.9±3.7(%). After transplantation, the hematocrit markedly increased to 68.6±4.2(%) 2 wk, and to 68.5±4.0(%) 7 wk after the transplantation. Serum human EPO concentration determined by ELISA indicated a persistent steady EPO production from the transplanted muscle cells 8 wk after the transplantation. The fate of transplanted myoblasts in uremic mice was monitored by transplanting the EPOsecreting clone which had also been transduced with BAG retrovirus bearing the fi-galactosidase gene. 8 wk later, Xgal positive myofibers were detected in the entire transplanted area. The results demonstrate that myoblasts can be transplanted in uremic mice, and that myoblast gene transfer can achieve sufficient and sustained delivery of functionally active EPO to correct anemia associated with

Long-term production of erythropoietin after electroporation-mediated transfer of plasmid DNA into the muscles of normal and uremic rats

“…Until now, there were only three reports on the continuous delivery of Epo in uremic animals by Epo gene transfer, ex vivo with a plasmid vector 11 or in vivo with an adenovirus vector. 12,13 There has been no demonstration of in vivo transfer of the Epo-encoding DNA plasmid in models of anemia with chronic renal failure.…”

“…There have been only three reports on the feasibility of Epo gene therapy for treating the anemia associated with chronic renal failure in animal models. [11][12][13] Consequently, the above-mentioned side-effects have not been examined in previous studies of Epo delivery by gene transfer. Therefore, it is important to assess the physiological effects of Epo gene expression in a model of anemia associated with chronic renal failure.…”

Myoblast Therapy: From Bench to Bedside

“…CTLA4Ig coexpression, associated with a transient anti-CD154 improvement in cardiac function (21). A further 10 patients were included, based on the following criteria: 1) treatment, can also prolong delivery of the recombinant protein, erythropoietin (Epo), via transfer of ex vivo severe left ventricular dysfunction (ejection fraction ≤35%); 2) the presence of a postinfarction akinetic and modified cells in allogeneic recipients (22,47). These efforts may improve the clinical success of myoblastnonviable scar, as assessed by dobutamine echocardiography and 18-fluorodeoxyglucose positron emission tobased therapy for treatment of DMD in the future.…”

“…Recent attempts of gene-modified myoblast strated that the autologous myoblast transplantation improved pump function, with a tendency for improved therapy have been expanded to insulin-dependent diabetes mellitus (IDDM) (49), neuropathy (29), anemia of systolic function, at up to 12 months into follow-up (51). Because all patients in this study had a MI at least 2 end-stage renal failure (ESRF) with recombinant erythropoietin (EPO) (22,47), and human growth hormone years before the cell transplantation, the myoblast therapy truly increased the contractility. They also demon-(hGH) (14).…”

Sustained gene expression in transplanted skin fibroblasts in rats

“…Transduced skeletal myoblasts have been used to deliver erythropoietin in mice [12][13][14] and transplantation of retrovirally transduced skeletal muscle myoblasts has been successfully achieved in dogs with alpha-l-iduronidase deficiency. 15 Smooth muscle cells are present within the vasculature as a multilayered mass of long-lived cells in proximity to the circulation and have been investigated as targets for gene therapy.…”