Targeting antigen-specific receptors on B lymphocytes to generate high yields of specific monoclonal antibodies directed against biologically active lower antigenic peptides within presenilin 1

We describe a targeting technique that selects antigen-specific receptors o n B lymphocytes using antigen driven selective production of monoclonal ant ibodies which are directed against functional peptide sequences within the presenilin 1 molecule that is believed to be related to the early-onset of familial Alzheimer's disease. Three different peptide sequences of presenil in 1 were constructed, one including the region around the amino acid posit ion 300, where the putative cleavage site exists and the other two present in the N- and C-terminal regions of that site. The efficiency in production of the desired monoclonal antibodies was at least 5-40-fold that obtained with the poly(ethylene glycol) (PEG)-mediated method. In addition, monoclon al antibodies directed against each of the peptide sequence displayed a hig h specificity for the corresponding peptide, in contrast to the lack of suc cess using the PEG method. Also, the selection of surface immunoglobulin re ceptors on B lymphocytes by the peptides of interest was confirmed by immun ofluorescent analysis. Here we demonstrate that targeting B lymphocytes res ults in the successful and efficient production of highly specific monoclon al antibodies against the lower antigenic peptide sequences. (C) 2001 Elsev ier Science B.V. All rights reserved.