Pii: S0167-5699(97)01238-3
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binding motifs of major histocompatibility complex (MHC) proteins, originally discovered by pool sequencing of MHC class I-bound peptides1, provide a biochemical basis for the phenomenon of MHC restriction of T-cell responses. However, the analysis of class II peptide motifs has proved difficult due to the heterogeneity in peptide length2–4. This problem has been overcome using several approaches to characterize the binding motifs of human HLA-DR class II proteins (reviewed in Ref. 5). The understanding of the specificity of peptide–MHC class II interactions was greatly facilitated by the three-dimensional structures of HLA-DR1 (Ref. 6) and of its complex with a peptide7. Similar to class I molecules, the HLA-DR structure revealed pockets in the peptide-binding groove accommodating several ‘anchor’ residues in a peptide. The specificity of these pockets is influenced by polymorphic residues, resulting in allele-specific class II motifs. The consensus core sequence of peptides binding to HLA-DR appears to be a nonamer with anchor residues at positions 1, 4, 6 and 9 (Ref. 5). Position 1 (P1) appears critical for binding and is invariably occupied by either aromatic or aliphatic residues. In addition, the murine class II I-E molecules, which are closely homologous to HLA-DR, were shown to be similar in their structure8 and binding motifs9,10. The amino acid usage at the anchor positions in DR/I-E motifs seems to be more flexible than in class I motifs, allowing several possible residues at each position. Nevertheless, the overall combination of several positions results in a stringent binding motif. In contrast to the well-characterized DR/I-E motifs, the peptidebinding specificity of human HLA-DQ and particularly of the murine H-2A (I-A) MHC class II proteins is controversial.
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Pii: S0167-5699(00)01750-3
with EBV: polyreactive antibodies and CD5 B lymphocytes. Annu. Rev. Immunol. 7, 513–525 52 Kipps, T. and Carson, D.A. (1993) Autoantibodies in chronic lymphocytic leukemia and related systemic autoimmune diseases. Blood 81, 2475–2487 53 Diehl, L.F. and Ketchum, L.H. (1998) Autoimmune disease and chronic lymphocytic leukemia: autoimmune hemolytic anemia, pure red cell aplasia, and autoimmune thr...
متن کاملPii: S0167-5699(99)01561-3
has gained widespread acceptance as a tool for quantifying cells that possess observable functional activities. Thoroughly planned titration experiments can produce straightforward and interpretable single-hit kinetics, whereas analyses of unfractionated cell populations over a broader dilution range result in data that deviate from linearity and do not adhere to all-or-none functionality (e.g....
متن کاملPii: S0167-5699(00)01668-6
29 Winter, G. et al. (1994) Making antibodies by phage display technology. Annu. Rev. Immunol. 12, 433–455 30 Jakobovits, A. et al. (1995) Production of antigen-specific human antibodies from mice engineered with human heavy and light chain YACs. Ann. New York Acad. Sci. 764, 525–535 31 Wagner, S.D. et al. (1994) The diversity of antigen-specific monoclonal antibodies from transgenic mice beari...
متن کاملPii: S0167-5699(99)01549-2
sponses are characteristic of autoimmune and infectious diseases. In recent years, substantial progress has been made in understanding the immunological basis of organ-specific autoimmune responses, whereby cell destruction by self-reactive immune effector cells leads to specific tissue pathology and disease1–3. More recently, significant advances have been made in understanding how some viruse...
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