Amyloid fibril protein related to immunoglobulin lambda-chains

Area of Science:

• Biochemistry
• Immunology
• Pathology

Background:

• Primary amyloidosis is a systemic disease characterized by amyloid fibril deposition.
• The exact composition and origin of amyloid fibrils can vary depending on the type of amyloidosis.

Purpose of the Study:

• To characterize the N-terminal sequence of amyloid fibrils isolated from a patient with primary amyloidosis.
• To determine the antigenic relationship between the isolated amyloid fibrils and soluble factors in the patient's serum.

Main Methods:

• Isolation and purification of amyloid fibrils from patient spleen tissue.
• N-terminal amino acid sequencing of the isolated amyloid fibrils.
• Preparation of antiserum against the purified amyloid protein.
• Immunological detection of soluble factors in patient serum using the prepared antiserum.

Main Results:

• The N-terminal sequence of the amyloid fibrils exhibited significant homology with lambda Bence Jones proteins.
• The antiserum detected a soluble factor in the patient's serum that was antigenically identical to the isolated amyloid fibrils.

Conclusions:

• The amyloid fibrils in this case of primary amyloidosis are likely derived from lambda Bence Jones proteins.
• A soluble precursor or related form of the amyloid fibril protein circulates in the patient's serum.