Useful polyclonal antibodies against synthetic peptides corresponding to immunoglobulin light chain constant region for immunohistochemical detectionof immunoglobulin light chain amyloidosis

For the immunohistochemical detection of immunoglobulin (lg) light chain am yloidosis on formalin-fixed, paraffin-embedded tissue sections, we prepared polyclonal antibodies against synthetic peptides corresponding to position s 118-134 of Ig lambda light chain and positions 116-133 of Ig kappa light chain. Nineteen cases of systemic Ig lambda light chain amyloidosis (A lamb da amyloldosis), 10 cases of systemic lg kappa light chain amyloidosis (A k appa amyloidosis), one case of immunohistochemically unclassified systemic amyloidosis and five cases of localized A lambda amyloidosis were tested wi th these antibodies, Anti-lambda (118-134) antiserum and the affinity-purif ied antibody both reacted with 18 of the 19 cases of systemic A lambda amyl oidosis and all cases of localized A lambda amyloidosis, although the immun oexpression was somewhat variable in intensity in different areas within th e same specimen in both systemic and localized amyloidosis. The signal inte nsities in plasma cells and serum reacted for anti-lambda (118-134) antiser um were weaker than signals obtained with commercially available anti-lg la mbda light chain antibodies, Anti-kappa (116-133) antiserum and the affinit y-purified antibody reacted with nine of the 10 cases of systemic A kappa a myloidosis, We conclude that these antibodies against synthetic peptides co rresponding to the lg light chain constant region are useful for the classi fication of amyloidosis on formalin-fixed, paraffin-embedded tissue section s.