Characterization of immunoglobulins in Hodgkin cells

Fifteen of 42 formalin‐fixed lymph‐node biopsies with Hodgkin lesions of different histological types and stages gave positive staining for immunoglobulins by the peroxidase/antiperoxidase method. The immunoglobulins in all the positively stained Hodgkin cells were of IgG type, but staining for IgA, D and E was negative. One of the 15 biopsies was positive for IgM. Thirteen of the 15 positive biopsies were positive for both χ and λ. Sequential double staining using two different substrates for peroxidase showed that most of the Hodgkin cells simultaneously contained light chains of both χ and λ type. It is concluded that Hodgkin cells do not contain a “monoclonal” immunoglobulin product.