Immunological Distinction between Neurofilament and Glial Fibrillary Acidic Proteins by Mouse Antisera and Their Immunohistological Characterization (Part 1 of 2)

Abstract

Antisera were raised in mice to the presumed protein subunits of the 2 types of 100 .ANG. filaments in nervous tissue, glial fibrillary acidic (GFA) protein and neurofilament (NF) protein. These antisera detect a pronounced antigenic distinction between these 2 proteins. Antiserum to GFA protein reacted only with astroglial cells and was similar to antisera prepared in rabbits. Mouse antiserum to NF protein reacted with neurons and their processes known to be rich in 100 .ANG. filaments. Postsynaptic densities did not detectably react with anti-NF antiserum when assayed by the indirect immunoperoxidase method and studied at the EM level. The 2 antisera did not react with actin, myosin or tubulin containing non-neural or neural tissues. During development of the mouse nervous system, NF protein was immunohistologically detectable at embryonic day 13 (the earliest stage tested). GFA protein was not detectable with this method during embryonal development but became apparent only at early postnatal ages. In several species (rabbit, rat, chicken, fish, turtle and frog), anti-NF protein antiserum only reacted with neurons, and anti-GFA protein antiserum stained glia exclusively. On the surface of trypsin-dissociated, single live cerebellar cells from 7-day-old mice, each antiserum detected antigenic specificities which were cross-reactive with its corresponding antigen.