Immunology Graduate Group
Michael P. Madaio, M.D.
Professor of Medicine
University of Pennsylvania School of Medicine
Address: 700 Clinical Research Building
University of Pennsylvania
415 Curie Boulevard
Philadelphia, PA 19104-6144
Office Phone: 215 573 1839
Lab Phone: 215 898 0625
Fax: 215 898 0189
Email: madaio@mail.med.upenn.edu
http://renal2.med.upenn.edu/RehdWeb/glomerulonephritis.html
http://renal2.med.upenn.edu/RehdWeb/lupusnephritis1.html
Education:
Intern and Resident in Medicine, Medical College of Virginia, Richmond
Chief Resident in Medicine, Medical College of Virginia, Richmond
Clinical Fellow in Nephrology, Boston University, Boston
Research Fellow in Nephrology, Boston University, Boston
Research Fellow in Immunology, Tufts University, Boston
M.D., Albany Medical College
B.S., Fairfield University (Biology) 1970
Research Interests
Glomerulonephritis Due To Anti-GBM Antibodies, Lupus Nephritis
Research Summary
Glomerulonephritis mediated by antibodies to glomerular basement membrane (GBM) is the prototype of human glomerular disease produced by pathogenic antibodies to intrinsic glomerular components. The principal target of human anti-GBM antibodies is directed at a unique region within Éø3 type IV collagen. Anti-GBM antibody mediated nephritis, therefore, represents an autoimmune disease, where the major immune reaction is focused on a specific region of a well-defined autoantigen. This observation provides a unique opportunity to address disease-related questions pertaining to the immunologic and genetic basis of a specific group of human pathogenic antibodies, and recent technical advances have made the selection and large-scale production of human pathogenic autoantibodies possible. Our goal is to to define the genetic and structural features of human anti-GBM antibodies, and then use the information to devise strategies to alter the production and glomerular deposition of pathogenic anti-GBM antibodies.
Ongoing work includes generation of monoclonal human pathogenic anti-Éø3(IV) antibodies from patients with anti-GBM disease. The antibodies generated are being used to determine the genetic and structural basis of autoantibody production. The results should also provide important information relevant to the basis of human anti-GBM antibody interactions with Éø3(IV). The information derived from these studies should provide information relevant to the genes encoding human anti-GBM antibodies and the structural basis for Éø3 type IV collagen recognition by these immunoglobulins. With the information and reagents derived from these studies, our long-term goal is to design specific therapies aimed at modulation of anti-GBM antibody mediated diseases by either eliminating pathogenic B cells and/or inhibiting the deposition of anti-GBM antibodies, in vivo.
More recently we have developed a novel model of anti-GBM disease mediated by human autoantibodies. Following immunization with Éø3 (IV) NC1 collagen, Xenomouse II develops anti-GBM disease including crescentic glomerulonephritis and pulmonary hemorrhage. Pathogenic monoclonal human autoantibodies were produced that bind to Éø3(IV)NC1 and produce linear GBM staining of fixed and unfixed normal human glomeruli, in vitro. . Normal mice given MAbF1.1 develop linear BM deposits of human IgG associated with glomerulonephritis, whereas XMII develop crescentic glomerulonephritis and heavy proteinuria. This model should be useful to test therapeutic strategies targeted at human autoAb producing B cells.
Lupus Nephritis
The overall goal of this program is to develop a better understanding of the humoral and cellular events leading to lupus nephritis. Previous work involved identification of monoclonal autoantibodies with pathogenic properties; the nephritogenic IgG reproducibly formed glomerular immune deposits, accompanied by clinical and histologic evidence of nephritis after transfer to normal mice. Among this pathogenic subset, the location of immune deposits varied with the administered Ab, and this was associated with variations in disease expression. These phenotypes were reminiscent of different forms of human lupus nephritis. Subsequently it was observed that individual pathogenic Ab bound directly to intrinsic glomerular antigens to initiate deposit formation. Of particular relevance, the interactive antigen (i.e. cell surface, basement membrane) varied with the pathogenic autoantibody, and different autoantibody-glomerular antigen interactions were associated with differences in the location of immune deposit formation and disease expression. Based on these findings, it was postulated that interaction of the individual Ab with glomerular antigens, in vivo, represents an important mechanism of immune deposit formation, and these differences contribute to the phenotypic diversity observed both among the nephritogenic murine autoantibodies and individuals with lupus nephritis. Furthermore, it is proposed that the nature and location of the target antigen influence the nature of the subsequent inflammatory response, through direct effects on the local cell biology via direct effects on cell-matrix, cell-cell, and intracellular processes. Thus, a major goal of the studies is to fully identify the target glomerular cell surface antigens for nephritogenic lupus autoAb. In parallel, we plan to determine the relevance of these observations to human lupus nephritis. The experimental approach involves immunoprecipitation of the cell surface antigens, partial amino acid sequence analysis of the isolated proteins and then screening libraries for full length clones. Once isolated and identified, subsequent studies will determine the pathogenic relevance of this autoantibody-glomerular cell surface interactions in vivo.
In the investigation of pathogenic lupus autoAb, a subset of monoclonal anti-DNA IgG was identified, that penetrate cellular and nuclear membranes and localize within nuclei in vivo. In the kidney, this was associated with glomerular hypercellularity and proteinuria. These same autoantibodies penetrated the cultured living cells, and localized within nuclei. After direct interaction with cell membranes, energy-dependent cellular entry of IgG was mediated through their antigen binding regions. The cell surface protein involved in internalization is myosin 1. Once internalized, the IgG transit through the cytoplasm, cluster at the nuclear pore, and enter the nucleus (ATP dependent). Although the primary sequences of the V regions of the IgG vary to some extent, they share conformational motifs with each other and share nuclear localization sequence homology with other proteins that enter the nucleus. Of potential clinical relevance, these Ab react with DNase 1 intracellularly, inhibit functional activity of the enzyme and modulate apoptosis. Recently it was observed that the internalized Ab also effect p53 and calveolin expression in cells undergoing apoptosis. This pathway is being investigated as a potential cause of the functional effects of the Ab.
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Recent Publications
Sogabe H, Nangaku M, Ishibashi Y, Wada T, Fujita T Sun X, Miwa T, Madaio MP, Song WC: Increased Susceptibility of Decay-Accelerating Factor Deficient Mice to Anti-Glomerular Basement Membrane Glomerulonephritis. J Immunol 167: 2791-2797, 2001
Fields ML, Sokol CL, Eaton-Bassiri A, Seo S, Madaio MP, Erikson J: Fas/fas ligand deficiency results in altered localization of anti- double-stranded DNA B cells and dendritic cells. J Immunol: 167: 2370-8, 2001
Meyers KEC, Allen JA, Gehret J, Jacobovits A, Gallo M, Neilson, EG, Hopfer H, Kalluri R, Madaio MP: Human glomerular basement membrane autoantibody disease in Xemomouse II. Kidney Int 61: 1666-73, 2002
Sekiguchi DR, Jainandunsing SM, Fields ML, Maldonado MA, Madaio MP, Erikson J, Weigert M, Eisenberg RA: Chronic graft-versus-host in Ig knockin transgenic mice abrogates B cell tolerance in anti-double-stranded DNA B cells. J Immunol 168: 4142-53, 2002
Bloom RD, O'Connor T, Cizman B, Kalluri R, Naji A, Madaio MP, Intrathymic kidney cells delay the onset of lupus nephritis in MRL-lpr/lpr mice. Int Immunol: 14:867-871, 2002
Yin Z, Bahtiyar G, Zhang N, Liu, L, Madaio MP, Craft J: IL-10 regulates murine lupus J Immunol 168: 4142-53, 2002
Miwa T, Maldonado MA, Zhou L, Sun X, Cai DW, Werth V, Madaio MP, Eisenberg RA, Song W-C: Deletion of decay-accelerating factor (DAF CD55) exacerbates autoimmune disease development in MRL/lpr mice. Am J Pathol. Am J Pathol:161(3):1077-86, 2003
Schiffer L, Sinha J, Wang X, Huang W, Von Gonsdorff G, Schiffer M, Madaio MP, Davidson .A short term administration of costimulatory blockade and cyclophosphamide induces remission of systemic lupus erythematosus nephritis in NZB/W F (1) mice by a mechanism downstream of renal immune complex deposition. J Immunol 171: 489-97, 2003
Hancock WW, Tsai TL, Madaio MP, Gasser DL Cutting Edge: Multiple autoimmune pathways in kd/kd mice. J Immunol. 171:2778-8, 2003