A Theory of Lymphocyte Blast Transformation (LBT) and Malignant Change Based on Proteolytic Cleavage of a Trigger Peptide: the Detendomer

Abstract

Evidence is outlined associating proteolytic events with initiation of lymphocyte blast transformation (LBT) in both antigen-specific and nonspecific mitogen-induced stimulation. It is proposed that lymphocytes normally express the hinge region of the IgG molecule on their surface and that this peptide (pro – thr – cys – pro – pro – pro) approximately constitutes a trigger peptide or detendomer that, by virtue of its proteolytic cleavage, stimulates the cell to LBT and mitosis, the trigger becoming inoperative when NAGA is linked to the threonine. The concept is extended to the malignant cell, which would express a detendomer similar in amino acid sequence and function to the lymphocyte blast detendomer, and would be triggered in a similar way. Evidence for this is presented.