Prolonged amelioration of acute lung allograft rejection by sequential overexpression of human interleukin-10 and hepatocyte growth factor in rats

The effect of prolonged electroporation-mediated human interleukin-10 (hIL-10) overexpression 24 hours before transplantation, combined with sequential human hepatocyte growth factor (HGF) overexpression into skeletal muscle on day 5, on rat lung allograft rejection was evaluated. Left lung allotransplantation was performed from Brown-Norway to Fischer-F344 rats. Gene transfer into skeletal muscle was enhanced by electroporation. Three groups were studied: group I animals (n = 5) received 2.5 μg pCIK-hIL-10 (hIL-10/CMV [cytomegalovirus] early promoter enhancer) on day -1 and 80 μg pCIK-HGF (HGF/CMV early promoter enhancer) on day 5. Group II animals (n = 4) received 2.5 μg pCIK-hIL-10 and pUbC-hIL-10 (hIL-10/pUbC promoter) on day -1. Control group III animals (n = 4) were treated by sham electroporation on days -1 and 5. All animals received daily nontherapeutic intraperitoneal dose of cyclosporin A (2.5 mg/kg) and were sacrificed on day 15. Graft oxygenation and allograft rejection were evaluated. Significant differences were found between study groups in graft oxygenation (Pao(2)) (P = .0028; group I vs. groups II and III, P < .01 each). Pao(2) was low in group II (31 ± 1 mm Hg) and in group III controls (34 ± 10 mm Hg), without statistically significant difference between these 2 groups (P = .54). In contrast, in group I, Pao(2) of recipients sequentially transduced with IL-10 and HGF plasmids was much improved, with 112 ± 39 mm Hg (vs. groups II and III; P < .01 each), paralleled by reduced vascular and bronchial rejection (group I vs. groups II and III, P < .021 each). Sequential overexpression of anti-inflammatory cytokine IL-10, followed by sequential and overlapping HGF overexpression on day 5, preserves lung function and reduces acute lung allograft rejection up to day 15 post transplant as compared to prolonged IL-10 overexpression alone.

Safety and efficacy of allogeneic cell therapy in infarcted rats transplanted with mismatched cardiosphere-derived cells

Cardiosphere-derived cells (CDCs) are an attractive cell type for tissue regeneration, and autologous CDCs are being tested clinically. However, autologous therapy necessitates patient-specific tissue harvesting and cell processing, with delays to therapy and possible variations in cell potency. The use of allogeneic CDCs, if safe and effective, would obviate such limitations. We compared syngeneic and allogeneic CDC transplantation in rats from immunologically-mismatched inbred strains.

Prolonged amelioration of acute lung allograft rejection by overexpression of human interleukin-10 under control of a long acting ubiquitin C promoter in rats

BACKGROUND: The prolonged effect of electroporation-mediated human interleukin-10 (hIL-10) overexpression in skeletal muscle under the control of the constitutional polyubiquitin C promoter (pUb hIL-10) on rat lung allograft rejection was evaluated. METHODS: Left lung allotransplantation was performed from Brown-Norway to Fischer-F344 rats. Either 2.5 mug pCIK hIL-10 (hIL-10/cytomegalovirus early promoter enhancer) alone (Group I/sacrifice Day 5 and II/sacrifice Day 10) or in combination with 2.5 mug pUb hIL-10 (hIL-10/UbC promoter; Group III/sacrifice Day 10) were injected into the tibialis anterior muscle of the recipient, followed by electroporation 24 hours before transplantation. Animals in Control Groups IV and V without gene transfer were euthanized on Day 5 and 10, respectively. All animals received a daily non-therapeutic dose of cyclosporine A (2.5 mg/kg). RESULTS: In Control Group IV, complete rejection (median A3B3) was noted on Day 5 with a Pao(2) of 43 +/- 9 mm Hg. In recipients of Control Group V, measurement of gas exchange on Day 10 and rejection grading was impossible because of complete destruction of the allograft. Group I animals on Day 5 (233 +/- 123 mm Hg; p = 0.02 vs Group IV) and Group II animals on Day 10 (150 +/- 139 mm Hg; p = 0.15 vs Group IV) demonstrated improved graft function. Graft function in Group III was further improved on Day 10 (299 +/- 123 mm Hg; p = 0.002 vs Group IV; p = 0.05 vs Group II; p = 0.36 vs Group I). Rejection was significantly reduced in Group III (median, A2B2) compared with Group II (median, A4B3; p < 0.05). CONCLUSIONS: Interleukin-10 overexpression under control of the constitutive ubiquitin C promoter ameliorates acute rejection and preserves lung graft function for a prolonged time.