ABSTRACT
Monoclonal light chains, i.e., Bence Jones proteins, are responsible for the characteristic pathologic features found in patients with the light chain-related diseases that include myeloma nephropathy, light chain deposition disease, light chain amyloidosis, and acquired Fanconi’s syndrome. These disorders result from clonal proliferation of plasma cells that leads to the deposition of their Ig products as amorphous casts, punctate precipitates, highly ordered fibrils, or intracellular crystals, respectively. The preeminent role of monoclonal light chains in the pathogenesis of the light chain-associated diseases has been demonstrated experimentally using both in vivo and in vitro models. Injection into mice of Bence Jones proteins resulted in the renal or systemic deposition of human light chains in a manner comparable to that found in the patient from whom the components were derived. Further, mice receiving non-pathologic proteins had no demonstrable light chain-related lesions.
