Three Kinds of Tumour‐Unique Surface Molecules on a Human T‐Cell Chronic Lymphocytic Leukaemia (T‐CLL) Detected by Monoclonal Antibodies

Mouse monoclonal antibodies recognizing cell surface molecules on tumour cells from a patient with a T-cell chronic lymphatic leukaemia (T-CLL) have been produced. Three different types of idiotype-like cell surface structures were identified. One molecule had a relative molecular weight (Mr) of 90,000 under non-reduced conditions and of 42,000 upon reduction, which corresponds well to the T-cell receptor for antigen (Ti). The two other molecules, which also behaved like unique tumour markers, have not previously been described, to our knowledge. One molecule was a monomer with an Mr of 74,000-80,000 when non-reduced and 80,000 upon reduction. The other idiotypic molecule was a dimer with a non-reduced Mr of 74,000-80,000, and 38,000 after reduction.