Mononuclear cell infiltrate, HLA-Dr expression and proliferation in 37 acoustic schwannomas

Abstract

Frozen sections from 37 schwannomas of the V111 nerve were reacted with a panel of monoclonal antibodies to macrophage, lymphocyte, I-ILA-Dr invariant chain and nuclear proliferation antigens. A moderate number of rnacrophages was demonstrated in 96% of tumours. CD8- and CD4- lymphocytes were detected in slightly smaller numbers in up to 87% and 23% of tumours respectively. B-lyrnphocytes were present in only 2/32 cases and NK-cells were absent from all 16 cases tested. HLA-Dr antigen was expressed by macrophages in most cases and by tumour cells in 13/24 tumours. These findings may represent evidence for a degree of cellular immune response. Occasional cells featuring nuclear proliferation were detected in 15/27 cases.