Establishment and Characterization of an Amylase-Producing

Two stable lines of IgA X-producing plasma cells (KHM-1 A and KHM-1 B) that were free of the Epstein-Barr virus were established from a patient with multiple myeloma compli-cated by hyperamylasemia. Surface marker studies of the two cell lines showed that the cells had no surface immu-noglobulins but were positive for cytoplasmic immuno-globulins (IgA X) and for HLA-DR and PCA-1. Secretion of H YPERAMYLASEMIA resulting from ectopic produc-tion of amylase by tumor tissue was first described by Weiss et aP in 1 95 1. Since then, several cases of hyperamyla-semia have been reported, especially in pulmonary and ovarian cancers.2’3 However, only one amylase-producing cell line has been established, that being from gastric carci-noma.’4 In addition, malignant plasma cells have also proved to be very difficult to establish, and only a little over ten human myeloma cell lines have been reported.24 In this study, we established two human myeloma cell lines, named KHM-1A and KHM-1 B, from a patient with IgA A multiple myeloma. KHM-lA cells secreted only IgA, while KHM-1B cells secreted IgA and a-amylase. This is the first report, to the best of our knowledge, of an amylase-producing nonepi-thelial cell line