Bence-Jones protein characteristics

Ultracentrijugation. In those laboratories where an ultracentrifuge is available, the pattern obtained of the serum of a patient with Waldenstrom macroglobulinemia is very characteristic. Frequently more than 30% of the total serum proteins could be accounted for by the 19 S peak. Bence Jones protein is not an uncommon finding in patients with Waldenstrom macroglobulinemia and was detected in patients both in Nigeria and Jamacia with the disease. 

That amyloid fibrils can be formed from Vl peptides was demonstrated by Glenner et al. (127) and by Linke et al. (128). Glenner et al. treated Bence Jones proteins of types k and X with pepsin in such a manner as to cleave the chains into V and C segments (129). During the incubation, precipitates formed in many of the solutions. Under the microscope some of these precipitates (nearly all from X chains) were seen to consist of fibrils resembling those of amyloid deposits. Furthermore, the X-ray diffraction pattern had a gross appearance characteristic... 

Preliminary X-ray crystallographic analyses have been carried out on another human myeloma protein [protein Meg, IgGl(X)] by Ed-mundson et al. (9). This protein has the interesting characteristic that a portion of each H chain is deleted the deletion comprises 15 residues in the hinge region. The protein was shown to possess a twofold axis of symmetry, with the asymmetric unit consisting of one L and one H chain. The Bence Jones protein (X chain dimer) of this patient was also crystallized and subjected to X-ray analysis (Section 1,E). 

The characteristics of Bence-Jones proteins have been discussed in Section III under multiple myeloma (page 202). 

This is a rather uncomiiion tumor of unique properties, composed usually of characteristic myeloma (abnormal plasma) cells originating in the bone marrow (7, 10, 100, 222-227, 328). This disorder has excited special interest since 1848 when Bence-Jones described the peculiar solubility characteristics, upon heating, of the protein found in the urine of a patient with this disease. More recently, multiple myeloma has attracted attention because of the unusually high incidence and degree of hyperproteinemia encountered, the diverse character of the protein increment as judged by various methods of fractionation, and the variety of unusual phenomena associated with the hyperproteinemia. Considered from the point of view of the effect of disease upon the plasma protein pattern, multiple myeloma clearly is a special case exhibiting peculiarities not encountered in any other disorder. 

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