Kokubyo Gakkai Zasshi. 2000 Jun;67(2):146-54. Unique Identifier :
CTLA-4 is a negative regulator for T cell activation and plays an
important role in down-regulating immune responses and the maintenance
of peripheral tolerance. The effect of initial treatment with
anti-CTLA-4 mAb on murine acute and chronic graft-versus-host diseases
(GVHD) induced by transfer of either C57BL/6 or BALB/c splenocytes into
F1 recipient mice has been investigated. The treatment with anti-CTLA-4
mAb exacerbated the lethality of acute GVHD. Surprisingly, in a chronic
GVHD model, the similar treatment with anti-CTLA-4 mAb significantly
reduced serum IgE and IL-4 expression and ameliorated the manifestation
of chronic GVHD. Analysis of the splenic phenotype revealed that
blockade of CTLA-4 greatly enhanced donor T cell expansion, especially
within the CD8 subset. The transfer of CD8-depleted splenocytes did not
exhibit the inhibitory effect by the anti-CTLA-4 mAb treatment,
suggesting that CD8 T cells are required for an inhibitory effect of
anti-CTLA-4 mAb. The regulatory roles of CD8 T cells and CTLA-4 pathway
blockade in Th2-mediated immune responses were further confirmed by in
vitro experiments using BALB/c T cell responses to allo-antigen. The
immunosuppressive effect of CTLA-4 blockade and the regulatory function
of CD8 T cells in Th2-mediated immune responses were demonstrated.
JOURNAL ARTICLE Animal Antibodies, Monoclonal/IMMUNOLOGY/THERAPEUTIC
USE Antibody Formation/*IMMUNOLOGY Antigens,
Differentiation/*PHARMACOLOGY CD8-Positive T-Lymphocytes/*PHYSIOLOGY
English Abstract Female Graft vs Host Disease/IMMUNOLOGY/THERAPY
IgE/METABOLISM Immunosuppressive Agents/*PHARMACOLOGY Interferon Type
II/METABOLISM Interleukin-4/METABOLISM Mice Mice, Inbred Strains
Signal Transduction Th2 Cells/*IMMUNOLOGY