High-molecular-weight hydroxyproline-protein in relation to immunoglobulins M (IgM) in human blood serum

Distribution of plasma-bound hydroxyproline in breast cancer, benign breast disease and healthy females

In normal adult females, patients with benign breast disease and patients with breast cancer, hydroxyproline (OHPro) was found in the plasma attached to the protein fractions which were separated by Sephadex gel filtration. In addition, a distinct moiety, probably a protein sub-unit, containing substantial amounts of this imino acid, occurred in between gel filtration fractions III and IV. Quantitative differences in the OHPro content of these various fractions were observed in the groups of patients studied. Significant elevations in the peptide-bound OHPro (fraction IV) were found only in patients with breast cancer and the level appeared to correlate with the degree of advancement of the disease. Similar findings relate to the OHPro content of the sub-protein moiety which is found between gel filtration fractions III and IV. A reduced level of high molecular weight hyproprotein (fraction I) was found in the breast cancer group.

Some properties of monoclonal cryoglobulin M appearing in the course of malignant lymphoma with macroglobulinemia

Monoclonal cryoglobulin IgM was separated from the serum of a patient with malignant lymphoma and macroglobulinemia. The purified cryoglobulin in immunoelectrophoresis formed the precipitin lines with anti-mu and anti-kappa serum and showed an abnormal electrophoretic mobility due to large aggregate formation. In comparison to normal IgM preparations a significantly lower content of hydroxyproline was found in the cryoglobulin studied. The possible role of hydroxyproline-containing peptides in the formation of the oligomeric structure of the IgM molecule is discussed.