Kamesaki H

Malignant histiocytosis with rearrangement of the heavy chain gene and evidence of monocyte—macrophage lineage

A unique case of malignant histiocytosis (MH) is reported. Its origin from the monocyte—macrophage system was indicated by expression of highly specific myeloid cell markers (My4, MCS2, and cytoplasmic lysozyme), diffuse activity of acid phosphatase and NaF‐sensitive α‐naphthyl acetate esterase, lack of immunologic markers specific for other cell lineages, and germ line configuration of the immunoglobulin light chain gene and the T‐cell receptor β‐chain gene. Its neoplastic nature was suggested by the single rearranged band of the immunoglobulin heavy chain gene.

A Novel B Cell Line Established from Ki-1-positive Diffuse Large Cell Lymphoma

A novel cell line, designated KIS‐1, was established from a patient with Ki‐1‐positive diffuse large cell lymphoma. Multiple phenotypic analysis of the KIS‐1 cells was carried out with a total of 22 monoclonal antibodies defining hematopoietic cell subsets and lineages. The KIS‐1 cells were positive for Ki‐1, B4, HLA‐DR, and 2D1 (common leucocyte) antigens, but were negative for the antigens reportedly specific for T cells, natural killer cells, granulocytes, monocytes, interdigitating reticulum cells and dendritic reticulum cells. The genomic analysis of the KIS‐1 cells showed not only the rearrangement of JH and Jk genes but also the probable rearrangement of Cγ genes. Moreover, the cells produced immunoglobulin γ chains. Thus, KIS‐1 was considered to be of B‐cell lineage. The lymphoma‐cell derivation of KIS‐1 was based on the following facts. The cytochemical, immunologic, cytogenetic properties and the results of the molecular genomic analysis in the KIS‐1 cells were essentially the same as those of the original tumor cells, and the KIS‐1 cells were negative for Epstein‐Barr virus‐associated nuclear antigen. KIS‐1 is the only known B‐cell line derived from Ki‐1‐positive diffuse large cell lymphoma, and should be useful for defining the biological implications of Ki‐1 antigen.

A New Hypothesis on the Cellular Origin of Reed-Sternberg and Hodgkin Cells Based on the Immunological and Molecular Genetic Analysis of the KM-H2 Line

Previously we reported a novel cell line, KM-H2, established from the pleural effusion of a patient who was initially diagnosed as having Hodgkin’s of mixed cellular type (Kamesaki et al. 1986). We describe here the results of further investigation of this line (ultrastructural, immunological, and molecular genetic studies) and discuss its cellular origin. Based on these analyses of the KM-H2 line, as well as those of other cell lines derived from Reed-Sternberg and Hodgkin cells (e.g., L428, L540), we propose a new hypothesis for the cellular origin of Hodgkin’s disease.