Progress Report for Contract N00014-94-C-0021 (Massachusetts General Hospital).
Abstract
At the time of our last report (Oct 30, 1994) we were frustrated by several problems that resulted in the lack of a single amino acid sequence mimicking the active site of LPS binding protein (LBP). We had narrowed the sequence to a region between 86 and 106. By varying the amino terminal using overlapping sequences, we determined that the smallest peptides that retained LPS binding activity terminated with residue 86. Two questions remained concerning the C terminal. First, the importance of amino acids at positions 103-106 were in doubt. Second, most of our earlier peptides had been generated with a terminal cysteine on the C terminal to facilitate coupling to IgG. We were concerned that some of these peptides could have spontaneously dimerized, raising the possibility that some of the binding activity was due to dimers rather than monomers of peptides. At this point we have shown that we can create LBP-IgG conjugates that bind LPS in buffer with high affinity. These same peptides block the action of LPS in assays of cytokine release. The next stage of the project is to vary aspects of the coupling (number of peptide copies/IgG, linker molecule) for desirable properties and to scale up for animal studies. In order to avoid time consuming and expensive experiments in several directions at once, a single peptide sequence is needed. We therefore focused our time over the last trimester in identifying our single best LBP peptide. As noted in our last progress summary, we simultaneously started to study the stability and properties peptide-IgG conjugates based on another LPS binding peptide (CAPl8).
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 07, 1995
- Accession Number
- ADA300537
Entities
People
- H. S. Warren
Organizations
- Massachusetts General Hospital