Inhibition of Graft Versus Host Disease Using CD4+ CD25+ T Cells Induced with Interleukin-2 in Mismatched Allogeneic Murine Hematopoietic Stem Cell Transplantation

Abstract

Background: In kidney transplantation, donor specific transfusion may induce tolerance as a result of some immune regulatory cells against the graft. In organ transplantation, the immune state arises from a relationship between the immunocompromised graft and the immunocompetent host. However, a reverse immunological situation exists between the graft and the host in hematopoietic stem cell transplantation (HSCT). In addition, early IL-2 injections after an allogeneic murine HSCT have been shown to prevent lethal graft versus host disease (GVHD) due to CD4+ cells. We investigated the induction of the regulatory CD4+CD25+ cells after a transfusion of irradiated recipient cells with IL-2 into a donor. Methods: The splenocytes (SP) were obtained from 6 week-old BALB/c mice (H-2) and irradiated as a single cell suspension. The donor mice (C3H/ He, H-2) received 5×10 irradiated SP, and 5,000 IU IL-2 injected intraperitoneally on the day prior to HSCT. The CD4+CD25+ cell populations in SP treated C3H/He were analyzed. In order to determine the in vivo effect of CD4+CD25+ cells, the lethally irradiated BALB/c were transplanted with 1×10 donor BM and 5×10 CD4+CD25+ cells. The other recipient mice received either 1×10 donor BM with 5×10 CD4+ CD25cells or the untreated SP. The survival and GVHD was assessed daily by a clinical scoring system. Results: In the MLR assay, BALB/c SP was used as a stimulator with C3H/He SP, as a responder, with or without treatment. The inhibition of proliferation was 30.0±13% compared to the control. In addition, the MLR with either the CD4+CD25+ or CD4+CD25cells, which were isolated by MidiMacs, from the C3H/He SP treated with the recipient SP and IL-2 was evaluated. The donor SP treated with the recipient cells and IL-2 contained more CD4+CD25+ cells (5.4±1.5%) than the untreated mice SP (1.4±0.3%)(P<0.01). There was a profound inhibition in the CD4+CD25+ cells (61.1±6.1%), but a marked proliferation in the CD4+CD25cells (129.8±65.2%). Mice in the CD4+CD25+ group showed low GVHD scores and a slow progression from the post-HSCT day 4 to day 9, but those in the control and 287 Immune Network ꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏ 책임저자:정대철, 성모자애병원 소아과, ꂕ 403-720, 인천시 부평구 부평 6동 665 Tel: 032-510-5687, Fax: 032-503-9724, E-mail: dcjeong@olmh.cuk.ac.kr 이 논문은 2003년 가톨릭중앙의료원 성의장학 연구비원과제비에 의해 이루어졌음. 288 Jae Ho Hyun, et al