Fragments and subclasses of IgG in eluates of human malignant tissues.
Eluates of 13 malignant tumours were prepared at 56 degrees C using the continuous flow technique. By using immunodiffusion techniques, 50--80 per cent of the IgG detected was found to be of the IgG1 subclass. The ratio of Ig/kappa to Ig/lambda was similar in eluates and in the corresponding extracts, and this ratio was similar to that obtained using pooled human serum. This indicates a normal distribution of IgG subclasses in the eluates. Besides whole IgG, the eluates and corresponding extracts contained fragments of IgG. This was revealed by using sodium dodecyl sulphate electrophoresis (SDS-PAGE). However, since parts of the IgG associated with human malignant tumours can be non-specifically bound, and since fragments of IgG was found in extracts and eluates of normal tissues, although to a lesser degree than in those of malignant tissue, no conclusive evidence was obtained that the malignant tissue could degrade Ig. SDS-PAGE of extracts and eluates of malignant tissues showed 2--3 constant bands not detected in isolated IgG or in extracts and eluates of most of the normal tissues. These bands were not identified.
D005354:Fibrosarcoma / Q000276:immunology*; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000032:analysis; D007141:Immunoglobulin Fc Fragments / Q000032:analysis; D007128:Immunoglobulin Fragments / Q000032:analysis*; D007074:Immunoglobulin G / Q000032:analysis*; D007145:Immunoglobulin kappa-Chains / Q000032:analysis; D007146:Immunoglobulin lambda-Chains / Q000032:analysis; D009369:Neoplasms / Q000276:immunology*
D007140:Immunoglobulin Fab Fragments; D007141:Immunoglobulin Fc Fragments; D007128:Immunoglobulin Fragments; D007074:Immunoglobulin G; D007145:Immunoglobulin kappa-Chains; D007146:Immunoglobulin lambda-Chains