Optimal fixation conditions for the immunoperoxidase identification of human J chain from tissue sections.

J chain can be used as a marker of plasmablasts and plasma cells at an earlier stage than intracellular immunoglobulin. Immunoperoxidase techniques were used to study optimal fixation conditions for the preservation of human J chain antigenicity in paraffin-embedded tissue sections. The most constantly positive staining for J chain combined with good morphological integrity was obtained with Bouin's fluid for 1.5 h at 20 degrees C. All other fixatives studied showed less consistent staining results.