α2‐Macroglobulin and other proteinase inhibitors do not interfere with the secretion of amyloid precursor protein in mouse neuroblastoma cells

Abstract
A series of proteinase inhibitors active against proteinases of all four major classes, including highly purified and well‐characterized α2‐macroglobulin, added to the cell culture medium of murine Neuro 2a neuroblastoma cells did not interfere with APP secretase activity. We therefore advance the hypothesis that APP secretase activity is localized in an intracellular compartment.