DEMONSTRATION OF A COMPLEMENT INACTIVATOR ON CULTURED CELLS FROM HUMAN MALIGNANT BRAIN TUMOURS

Human primary and secondary malignant, and primary benign brain tumours were short time cultured in order to detect a coating with a protein, immunologically indistinguishable from complement component Cl inactivator. The investigations were done by cytophotometry of immunoflurescence on individual cells from human brains. The cell cultures were incubated with specific rabbit antiserum against human Cl inactivator, conjugated with fluorescein isothiocyanate. The majority of the malignant brain tumours, and a few of the benign brain tumours, were shown to carry the Cl inactivator—resembling protein. The primary malignant brain tumour cells seemed to lose this coating during prolonged culturing. Metastatic brain carcinomas retained their inactivator coating.