Ryotaro Higuchi1, J Wayne Streilein. 1. Schepens Eye Research Institute and Department of Ophthalmology, 20 Staniford Street, Harvard Medical School, Boston, MA 02114, USA.
Abstract
PURPOSE: To determine the immunopathogenesis of delayed orthotopic corneal xenograft rejection in mice deficient in the xenoreactive CD4+ T cells that mediate acute rejection. METHODS: CB.17 SCID and BALB/c mice were used as recipients of orthotopic cornea grafts obtained from strain 13 guinea pigs. Before transplantation, SCID recipients, which do not normally reject guinea pig cornea grafts, were reconstituted with spleen cells (whole, CD4-depleted, CD4/CD8-depleted) or purified CD8+ T cells from normal BALB/c donors. Graft survival was assessed by clinical examination, and median survival times (MST) were calculated. Lymphocytes from mice that rejected guinea pig cornea grafts were analyzed in vitro for their capacity to respond to guinea pig xenoantigens and to lyse guinea pig target cells. RESULTS: SCID mice reconstituted with whole spleen cells from BALB/c donors rejected guinea pig corneas with a vigor identical with that of normal BALB/c mice (MST = 15 and 14 days, respectively), whereas SCID mice reconstituted with CD4-depleted BALB/c spleen cells rejected guinea pig corneas in a delayed fashion (MST = 27 days), as did SCID mice reconstituted with purified CD8+ T cells from BALB/c donors. Although CD8+ T cells from rejector mice failed to lyse guinea pig target cells in vitro, the T cells proliferated and secreted IFN-gamma in response to in vitro stimulation with guinea pig xenoantigens. CONCLUSIONS: Guinea pig cornea xenografts that avoid acute rejection in CD4+ T cell-depleted mice are vulnerable to rejection by CD8+ T cells. Effector CD8+ T cells destroy corneal xenografts through release of proinflammatory mediators (IFN-gamma) rather than by cytotoxicity.
PURPOSE: To determine the immunopathogenesis of delayed orthotopic corneal xenograft rejection in mice deficient in the xenoreactive CD4+ T cells that mediate acute rejection. METHODS: CB.17 SCID and BALB/c mice were used as recipients of orthotopic cornea grafts obtained from strain 13 guinea pigs. Before transplantation, SCID recipients, which do not normally reject guinea pig cornea grafts, were reconstituted with spleen cells (whole, CD4-depleted, CD4/CD8-depleted) or purified CD8+ T cells from normal BALB/c donors. Graft survival was assessed by clinical examination, and median survival times (MST) were calculated. Lymphocytes from mice that rejected guinea pig cornea grafts were analyzed in vitro for their capacity to respond to guinea pig xenoantigens and to lyse guinea pig target cells. RESULTS:SCIDmice reconstituted with whole spleen cells from BALB/c donors rejected guinea pig corneas with a vigor identical with that of normal BALB/c mice (MST = 15 and 14 days, respectively), whereas SCIDmice reconstituted with CD4-depleted BALB/c spleen cells rejected guinea pig corneas in a delayed fashion (MST = 27 days), as did SCIDmice reconstituted with purified CD8+ T cells from BALB/c donors. Although CD8+ T cells from rejector mice failed to lyse guinea pig target cells in vitro, the T cells proliferated and secreted IFN-gamma in response to in vitro stimulation with guinea pig xenoantigens. CONCLUSIONS:Guinea pig cornea xenografts that avoid acute rejection in CD4+ T cell-depleted mice are vulnerable to rejection by CD8+ T cells. Effector CD8+ T cells destroy corneal xenografts through release of proinflammatory mediators (IFN-gamma) rather than by cytotoxicity.
Authors: Hidetaka Hara; Naoko Koike; Cassandra Long; Jordan Piluek; Danny S Roh; Nirmala SundarRaj; James L Funderburgh; Yoshiaki Mizuguchi; Kumiko Isse; Carol J Phelps; Suyapa F Ball; David L Ayares; David K C Cooper Journal: Invest Ophthalmol Vis Sci Date: 2011-07-15 Impact factor: 4.799