J Exp Med. 1939 Apr 30;69(5):705-19. doi: 10.1084/jem.69.5.705.
The Journal of experimental medicine
K Landsteiner, J van der Scheer
PMID: 19870872 PMCID: PMC2133757 DOI: 10.1084/jem.69.5.705
Experiments are described dealing with immune sera to pentapeptides and peptide amides. Absorption and inhibition tests gave no indication of the presence in the immune sera of special antibodies for portions of a peptide molecule but the antibodies appeared to be specific for an entire pentapeptide even though the sera contained qualitatively different fractions. Marked disparity was found between the reactions of peptides and corresponding amides indicating differences between acid and other polar groups in their influence on serological specificity.