Showing papers by "David S. Ludwig published in 1989"

Structure-function analysis of protein active sites with anti-idiotypic antibody.

Abstract: Antigen and internal image-bearing anti-idiotypic antibody, owing to potential differences in size and chemical nature, need not necessarily demonstrate identical binding specificities. Such differences, termed "dissociability," may be exploited in structure-function analysis of receptor-ligand interaction to identify functionally important amino acid residues, define receptor class, or distinguish receptor conformation. In this sense, ligand and the anti-idiotypes they elicit constitute alternative and complementary probes of protein active sites.

Peptides Derived From HLA-A2 Modulate Lysis by HLA-A2-Specific Cytotoxic T Lymphocytes

Abstract: Understanding the molecular basis of T-cell recognition of major histocompatibility complex (MHC) antigens may allow new diagnostic and therapeutic approaches to transplantation. Recently it has been shown that in general T cells do not recognize antigens in their native form but rather as short linear protein fragments in the context of self MHC (1–3). These findings prompted us to investigate what role peptides derived from HLA molecules might play in human allorecognition. Two peptides corresponding to regions containing sequences unique to HLA-A2 were selected. These peptides specifically inhibit cytolysis by HLA-A2-specific cytotoxic T lymphocytes (CTL). Moreover, one of these peptides can sensitize a related HLA molecule to lysis by HLA-A2-specific CTL. The recently published crystal structure of HLA-A2 now makes it possible to draw more precise structure/function correlations in understanding the role of HLA molecules as peptide binding proteins.