Expression of the neurofibromatosis Type 2 gene in human tissues

The neurofibromatosis Type 2 tumor suppressor gene is implicated in the her editary tumor syndrome NF2, hallmarked by bilateral vestibular schwannomas, meningiomas, and ocular non-neoplastic features. The gene product has char acteristics of a membrane cytoskeleton-linking protein but the mechanism of tumor suppression by the NF2 protein remains to be elucidated. The NF2 gen e is widely expressed in mouse and rat tissues. In humans, most of the expr ession data have accumulated through Northern blot analysis, RT-PCR and, mo re recently, Western blot analysis, providing information on whole tissues and organs rather than on specific cell types. We report here an extensive survey of NF2 gene expression in human tissues using a combination of mRNA in situ hybridization (mRNA ISH) and immunohistochemistry (IH) with a panel of monoclonal antibodies (MAbs) supplemented by tissue immunoprecipitation experiments with affinity-purified polyclonal antibodies. Expression was o bserved in many different cell types, most of which appear functionally nor mal in individuals affected by NF2. Surprisingly, expression could not be c onsistently documented in Schwann cells and arachnoidal cells by IH or by m RNA ISH in formalin-fixed tissue. However, consistent immunostaining of Sch wann cells was seen In frozen sections.