The overall objective of the proposed studies is to better understand the etiology of autoimmune hemolytic anemia (AIHA) leading eventually to more rational patient management and therapy. AIHA may be idiopathic or develop as a complication of a variety of disorders. The heterogeneity of RBC autoantibodies in these clinical conditions as well as those present in the plasma of healthy individuals remains poorly defined. The proposed studies will examine the human B-cell repertoire in benign versus pathologic RBC autoantibodies and determine whether particular antibody producing clones play an important role in the expression of autoimmune hemolytic disease. RBC specific human B-cell clones will be established from patients with AIHA as well as from healthy individuals by EBV transformation and somatic hybridization techniques. These B- cell clones will be characterized with respect to: 1) The structure and function of their Ig product (isotype, subclass, isoelectric point, and specificity); 2) Their karyotype, surface phenotype and Ig gene rearrangements; and, 3) Their immunoglobulin variable region genes by serological methods (with antiidiotypes) and by molecular methods (cDNA sequencing of Ig variable regions; usage of VH and VL subgroups with cDNA probes).

Project Start
1988-05-01
Project End
1993-04-30
Budget Start
1990-05-01
Budget End
1991-04-30
Support Year
3
Fiscal Year
1990
Total Cost
Indirect Cost
Name
University of Pennsylvania
Department
Type
Schools of Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Siegel, D L; Silberstein, L E (1994) Expression and characterization of recombinant anti-Rh(D) antibodies on filamentous phage: a model system for isolating human red blood cell antibodies by repertoire cloning. Blood 83:2334-44
Jefferies, L C; Carchidi, C M; Silberstein, L E (1993) Naturally occurring anti-i/I cold agglutinins may be encoded by different VH3 genes as well as the VH4.21 gene segment. J Clin Invest 92:2821-33
Jefferies, L C; Silverman, G J; Carchidi, C M et al. (1992) Idiotypic heterogeneity of VKIII autoantibodies to red blood cell antigens. Clin Immunol Immunopathol 65:119-28
Friedman, D F; Moore, J S; Erikson, J et al. (1992) Variable region gene analysis of an isotype-switched (IgA) variant of chronic lymphocytic leukemia. Blood 80:2287-97
Reidl, L S; Friedman, D F; Goldman, J et al. (1991) Structural basis of a conserved idiotope expressed by an autoreactive human B cell lymphoma. Evidence that a VH CDR3 mutation alters idiotypy and specificity. J Immunol 147:3623-31
Friedman, D F; Cho, E A; Goldman, J et al. (1991) The role of clonal selection in the pathogenesis of an autoreactive human B cell lymphoma. J Exp Med 174:525-37
Silberstein, L E; Jefferies, L C; Goldman, J et al. (1991) Variable region gene analysis of pathologic human autoantibodies to the related i and I red blood cell antigens. Blood 78:2372-86
Jefferies, L C; Stevenson, F K; Goldman, J et al. (1990) Anti-idiotypic antibodies specific for a pathologic anti-Pr2 cold agglutinin. Transfusion 30:495-502
Andrzejewski, C; Young, P J; Goldman, J et al. (1989) Production of human warm-reacting red cell monoclonal autoantibodies by Epstein-Barr virus transformation. Transfusion 29:196-200