"Membrane-associated" immunoglobulins in cyst and ascites fluids of ovarian cancer patients.

A new column chromatography technique, utilizing peroxidase-labeled antihuman immunoglobulins, is described, which can measure the binding of specific antibodies to membrane fragments containing relevant antigens. Using this assay, the presence of bound immunoglobulin is demonstrated on membrane fragments isolated from ascites fluids, but not from tumor tissues. In this study, two populations of immunoglobulins were examined: 'free' immunoglobulins and immunoglobulins bound to ascites fluid-derived membrane fragments. Immunoglobulins eluted from membrane fragments of the ascites fluids were capable of binding to the tumor. These were specific for binding to tumor membrane preparations, in that there was two orders of magnitude greater binding of these immunoglobulins at a given concentration than 'free' immunoglobulins at the same concentration.