The identification and role of anti-immunoglobulins in human malignancy.

Anti-immunoglobulin antibodies, previously shown to occur in a number of diseases, have been identified in human solid tumour. These antibodies, including antiFabs (called serum agglutinators), are directed against various reagons of the IgG molecule. They were detected by means of a passive haemagglutination test. The anti- IgG molecules isolated by affinity chromatography and other techniques were found to belong to immunoglobulin classes IgA, IgG and IgM. In the majority of cases the serum agglutinators reacted with autologous and heterologous IgG molecules cleaved by pepsin and chymotrypsin (F(ab')2). The anti-F(ab')2 antibodies reacted with the anti-cytoplasmic tumour-antibodies but not with the anti-membrane antibodies. The leukocyte adherence inhibition (LAI) test was used to demonstrate the interaction between anti-tumour (cytoplasmio) antibody and anti-F(ab')2 antibody. The anti-antibody could represent an "unblocking factor" in this type of method of assessing cell mediated immunity. Finally, in vitro studies to investigate possible production of F(ab')2 fragments by human tumours were performed.Des anticorps dirigés contre des gammaglobulines humaines (et leur fragments Fab) ont été charactérisés chez les malades porteurs de tumeure solides. Ces anticorps ont été détéctés par la technique d'hémaglutination passive. Des anticorps anti-IgG (Fab) isolés par diverses méthodes appartiennent aux classes IgG, IgA, IgM. Dans la plupart des cas, ces anticorps ont réagi avec des fragments d'IGG obténus après action enzymatique (pépsine et chromotrypaine). Ceux fragments, eux aussi avaient des activités croissés contre des antigènes cytoplasmiques des cellules de mélanome malin