Induction of immune complex glomerulonephritis in F1 hybrid mice: superiority of cortisone-resistant parental thymocytes over spleen cells

L3T4+ T cells induce hepatic lesions resembling primary biliary cirrhosis in mice with graft-versus-host reactions due to major histocompatibility complex class II disparity

We had shown that the appearance of hepatic lesions such as epithelioid granulomas and chronic nonsuppurative destructive cholangitis (CNSDC)-like bile duct changes characteristic of primary biliary cirrhosis (PBC) in mice undergoing MHC class II-disparate graft-versus-host reactions (GVHR). To further examine the pathogenesis of the disease, we examined in the present study which T cell subset, i.e., L3T4+ or Lyt-2+ T lymphocytes, had an ability to induce such hepatic lesions. (B6 x bm12)F1 recipients were injected with unseparated T cells, L3T4+, or Lyt2+ T cells of B6 mice and on various days postinjection liver specimens were obtained. At Day 14 postinjection, livers of mice injected with whole T cells or L3T4+ T cells showed PBC-like histological changes, but none of the lesions were induced by Lyt-2+ T cells. Immunohistochemical studies revealed that Lyt-2+ as well as L3T4+ T cells were detected around bile ducts and some of them were infiltrating among bile duct epithelial cells. Kinetic studies showed that shortly after injection of L3T4+ T cells, L3T4+ T cells appeared around bile ducts and then Mac-1+ cells emerged. Lyt-2+ T cells and surface IgM+ B cells were detected on Day 5 and increased thereafter. Hepatic granulomas consisted of both L3T4+ and Lyt-2+ T cells with a few B cells. The aberrant expression of MHC class II (Ia) antigen was detected mainly at the lateral surface of bile duct epithelial cells by Day 14 postinjection. Based on these findings, the developmental mechanism of PBC-like hepatic lesions induced in mice with GVHR was discussed.

Ductal lesions of exocrine glands and insulitis induced by L3T4+ T cells following graft-versus-host reaction due to major histocompatibility complex class II disparity

Recently, we have demonstrated characteristic hepatic lesions resembling primary biliary cirrhosis (PBC) in semiallogeneic F1 hybrid mice with major histocompatibility complex (MHC) class II-disparate graft-versus-host reaction (GVHR). In the present study, we tried to reveal other ductal lesions in extrahepatic organs, including salivary glands and pancreas. Murine strains used are C57BL/6 (B6), B6 mutant bm1, and bm12. bm1 carries a mutant gene at the H-2K locus of MHC and bm12 carries a mutant gene at the I-A locus of MHC of the B6 strain. The (B6 x bm1)F1, (B6 x bm12)F1, and (bm1 x bm12)F1 mice were injected intravenously with 1 x 10(7) B6 L3T4+ or Lyt-2+ T cells and were sacrificed on the 14th day postinjection for histological examinations. Mononuclear cell infiltration was detected around the ducts of salivary glands only in (B6 x bm12)F1 mice injected with B6 L3T4+ T cells. A moderate to marked level of cell infiltration was demonstrated in pancreas of (B6 x bm12)F1 recipients similar to nonobese diabetic (NOD) mice. By immunohistochemical examinations, infiltrating cells were shown to consist not only of L3T4+ but also of Lyt-2+ T cells, even after the inoculation of L3T4+ cells. These results are discussed in reference to mechanisms of organ-specific autoimmune diseases, especially insulitis in NOD mice which show insulin-dependent diabetes mellitus.

Pathogenesis of experimental lupus nephritis: a role for anti-basement membrane and anti-tubular brush border antibodies in murine chronic graft-versus-host disease

The pathogenesis of renal involvement was studied in murine chronic graft-versus-host disease (GVHD), which is a model for human systemic lupus erythematosus. GVHD was induced by four i.v. injections of lymphocytes from DBA/2 donor mice into (C57BL/10 x DBA/2)F1 hybrids at 3-4-day intervals. Two weeks after the first injection, antibodies were found to have been deposited in the mesangium and along the glomerular basement membrane (GBM) in a linear arrangement, which changed to a granular pattern after 6-8 weeks. In this stage, large electron-dense complexes were present both subepithelially and subendothelially along the GBM. Proteinuria increased up to 11,300 +/- 2140 micrograms/18 h. Indirect immunofluorescence studies and ELISA showed that sera and kidney eluates contained autoantibodies directed against nuclear antigens and GBM component laminin as well as against renal tubular epithelial antigens (RTE). The specificity of the anti-RTE antibodies was further characterized by the use of absorption techniques as well as immunoblotting. The early linear immunofluorescence pattern seems to be associated with glomerular binding of anti-GBM antibodies, while electron-dense complex formation in later stages may be induced by the superimposed deposition of anti-RTE antibodies. Similar phenomena were recently described in Heymann's nephritis in the rat, a model for human membranous nephropathy.