Demonstration of Immunoglobulin in Tumor and Marginal Tissues of Squamous Cell Carcinomas of the Head and Neck 2

Abstract
Immunofluorescence (IF) techniques on cryostat-cut sections of tumor tissues demonstrated that immunoglobulin was associated with cells of squamous cell carcinomas of the head and neck. The immunoglobulin was found consistently to be of the IgG class; IgM and IgA were detected also but in only one tumor sample each. The C3 component of complement was also in most tumor tissues. The immunoglobulin could be removed from the tissues by being washed with low pH glycine buffer but not with pH 7 buffer, indicating that the immunoglobulin may be in antibody-antigen complexes. All the tissues obtained from the histologically normal margins of the surgical specimens were also positive for the presence of bound immunoglobulin, whereas head and neck epithelial tissues from tumor-free control patients were negative in the IF assays. Preliminary experiments showed that IgG from patients' diluted serum and the IgG fraction isolated from patients' serum would bind to glycine buffer-eluted tumor tissue.