[Immune tolerance induced by combined heart-thymus transplantation for heart allograft in rats].
OBJECTIVE
To explore the role of combined heart-thymus transplantation for heart allograft in rats.


METHODS
Vascularized heart-thymus combined transplantation was performed with microsurgical technique. Graft survival, histopathology, infiltration of CD4+, CD8+ T cells, level and mRNA expressions of IL-2 and IL-4 in the serum and cardiac grafts were investigated.


RESULTS
Heart allograft in the controls had a survival time of (6.0+/-0.76) d. heart-thymus combined transplantation in non-thymectomized rats had a survival time of (6.88+/-0.64)d (P<0.05). Heart-thymus combined transplantation in thymectomized rats led to an evident survival time of (14.13+/-5.82)d (P<0.01) for cardiac graft, which further obtained long term survival after short course of treatment with cyclosporine. Pathologic lesion and infiltration of CD4+ and CD8+ T cells in cardiac grafts showed mitigated in the long term survival group. IL-2 level in the serum and cardiac grafts maintained low level in the long term survival group, whereas IL-4 maintained high level.


CONCLUSIONS
Whether thymectomized or not in recipient rats, heart-thymus combined transplantation has a positive effect to protect cardiac graft. Furthermore, in thymectomized rats heart-thymus combined transplantation may lead to evident survival prolongation of the heart grafts, which induces immune tolerance in short course of treatment with cyclosporine.
Xiong
Hai-Bo
HB
Institute of Transplantation, Third Xiangya Hospital, Central South University, Changsha 410013, China. haiboxiong@sohu.com
Huang
Zu-Fa
ZF
Ye
Qi-Fa
QF
Xia
Sui-Sheng
SS
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D016572:Cyclosporine / Q000627:therapeutic use; D006085:Graft Survival / Q000187:drug effects / Q000276:immunology*; D016027:Heart Transplantation; D007108:Immune Tolerance / Q000187:drug effects / Q000276:immunology*; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007376:Interleukin-2 / Q000097:blood / Q000235:genetics; D015847:Interleukin-4 / Q000097:blood / Q000235:genetics; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013934:Thymectomy; D013950:Thymus Gland / Q000637:transplantation*; D013997:Time Factors; D014181:Transplantation Immunology / Q000276:immunology; D014184:Transplantation, Homologous
D007166:Immunosuppressive Agents; D007376:Interleukin-2; D015847:Interleukin-4; D016572:Cyclosporine