Accumulation of alpha B-crystallin in central nervous system glia and neurons in pathologic conditions.

Alpha B-crystallin, a major protein of the vertebrate lens, is found in the central nervous system (CNS) and is a major protein component of Rosenthal fibers (RF), intracytoplasmic inclusions within astrocytes. Its level of expression in the normal CNS is low and appears to be confined to glial cells, both astrocytes and oligodendrocytes. A number of human brains displaying a variety of pathologic changes were examined by immunohistochemistry with an anti-alpha B-crystallin antiserum and increased immunoreactivity was found in astrocytes and oligodendrocytes without the formation of RFs. Furthermore, some neurons in neurodegenerative disorders were also immunolabeled with the anti-alpha B-crystallin antiserum. Thus, the accumulation of alpha B-crystallin appears to be part of the repertoire of reactive processes of CNS glial cells and some neurons in pathologic conditions.