Antibodies to the cytoplasm, cell membrane and nuclear membrane of malignant neoplasms in pooled normal human polyspecific immunoglobulin G

IVIg is a preparation of normal polyspecific IgG obtained from pooled plasm a of a large number of healthy donors. IVIg treatment of patients with chro nic lymphocytic leukemia induced a reduction in the total number of lymphoc ytes in the peripheral blood. Regression of Kaposi's sarcoma was also noted in an HIV patient treated with IVIg. The aim of this study was to determin e whether F(ab')(2) prepared from IVIg binds to cellular structures of diff erent tumor tissues. Biotinylated F(ab')(2) was prepared from 3 different p reparations of IVIg and from affinity purified IgG from a patient with mult iple myeloma. Direct immunohistochemistry using a streptavidin peroxidase s taining method was performed on biopsy samples of 18 different tumor tissue s. Positive staining of the cytoplasm, cell membrane and nuclear membrane o f several types of malignant tumors by F(ab')(2) from IVIg was immunohistoc hemically demonstrated. Nuclear staining of tumor cells by IVIg was rare. I VIg bound to different tumors of epithelial origin, especially colon carcin oma, breast carcinoma and squamous cell carcinoma of the lung. Malignant tu mors of mesenchymal origin such as leiomyosarcoma have also demonstrated po sitive staining by IVIg. IVIg contains antibodies to the cytoplasm, nuclear membrane and cell membrane of different malignant tumors especially of epi thelial origin. This binding might provide a basis for the assumption that IVIg treatment of cancer patients may induce antibody dependent cell mediat ed cytotoxicity response against tumors, and implies that it can be potenti ally beneficial as adjuvant treatment of malignant diseases.