J. C. Cawley

The establishment and cytological, cytochemical and immunological characterisation of human haemic cell lines: Evidence for heterogeneity☆

Abstract Continuous tissue culture lines were established from the bone marrow or peripheral blood of 28 patients with haematological malignancies. The morphological and immunological properties of these newly established cell lines were studied after periods of 6 months to 2 years growth in liquid culture. Apart from a single T-cell line, all lines tested proved to be EBNA positive, and all but the T-cell lines and two others showed cell surface characteristics similar to those of blastoid lines of lymphoid origin. Nevertheless, many of the cell lines showed cytochemical positivity for alkaline phosphatase, not normally found in lymphoid precursors, most showed at least some positivity to both α-naphthol AS-D acetate and chloro-acetate esterases at near neutral pH, although not to α-naphthyl butyrate or chloro-acetate at pH 8. Three cell lines produced lysozymes and 10 of 13 lines tested showed phagocytic activity towards bacteria. Lysozyme production and phagocytic activity were found only in cell lines derived from patients with acute myeloid leukaemias, and alkaline phosphatase activity was more common in, though not confined to, such lines. The evidence indicates a wider enzymatic and functional diversity among established human haemopoietic cell lines than has hitherto been suspected.

New evidence relating to the nature and origin of the hairy cell of leukaemic reticuloendotheliosis.

Summary. New evidence is presented concerning the nature and origin of the pathognomonic cell of leukaemic reticuloendotheliosis (LRE). A specific receptor for IgM was demonstrated by an EAIgM rosette test in all seven cases of LRE studied. This marker was absent from the pathological cells of a wide variety of haematological proliferative disorders, and from cells of the normal myeloid and monocyte‐histiocyte series. A small percentage of circulating mononuclear cells which did not resemble monocytes morphologically, did possess the receptor for IgM. The LRE cells were found to show variable phagocytic activity for IgG opsonized erythro‐cytes and latex particles. Studies of differences in the kinetics of the rosette test in the seven cases together with the range of phagocytic activity and cytological maturity observed, suggested that the diagnosis of LRE may encompass a broader spectrum of clinical and cytological features than has previously been recognized. Evidence presented suggests that the cells of LRE are not related to either B‐lymphocytes or the monocyte‐histiocyte series. It is proposed that LRE represents a leukaemic proliferation of the newly identified small population of EAIgM receptor bearing normal circulating mononuclear cells.

Chronic myelomonocytic leukemia with paraproteinemia but no detectable plasmacytosis A detailed cytological and immunological study

A patient with chronic myelomonocytic leukemia with IgG K paraproteinemia, but no detectable plasmacytosis, is described. The patient was entering a blastic phase at the time of the most detailed studies. Cytological, cytochemical, and ultrastructural studies revealed a mixed myeloid proliferation with granulocytic forms predominating over monocytic elements. A variety of ultrastructural abnormalities, including defective granulation, was observed but no cells with highly developed rough endoplasmic reticulum were observed. Immunological marker studies showed that the mature myeloid cells possessed receptors for the Fc of IgG and weakly expressed the Ia‐like P29/34 antigen. The mature myeloid cells also expressed both surface and intracytoplasmic Ig restricted to IgG K, and this IgG K persisted after 4 weeks in culture. A reverse plaque assay showed that the myeloid cells were capable of releasing IgG K in vitro, but studies involving the incorporation of radio‐labeled amino acids showed no detectable Ig production by the myeloid cells. The possible interpretations of these data are discussed in some detail in relation to previous reports of paraproteinemia in myeloid proliferative disorders.

Cytochemical, ultrastructural and immunological studies of circulating Reed-Sternberg cells.

Reed–Sternberg (R–S) cells in the circulating blood of a patient with Hodgkins disease were cytochemically peroxidase and Sudan black negative, devoid of alkaline phosphatase and non‐specific esterase, mostly PAS negative but occasionally showing positivity, and nearly always showing moderately strong granular positivity for acid phosphatase. Electron microscopy showed irregular nuclear profiles, conspicuous nucleoli, a moderate development of cytoplasmic organelles but absence of structures resembling monocytic granules. The R–S cells frequently possessed receptors for the Fc region of IgG and were mostly positive for SmIg, but did not form rosettes with sheep or mouse erythrocytes nor have receptors for the Fc region of IgM or the C3 component of complement. The combined results suggest that R–S cells are of B‐cell lineage.

Distinctive cytoplasmic inclusions in chronic lymphocytic leukaemia

Abstract Distinctive cytoplasmic inclusions of a type hitherto given little attention are described in two of a series of thirty cases of chronic lymphocytic leukaemia. The possible nature and significance of these inclusions are discussed and attention is drawn to their similarity to inclusions prominent in leukaemic reticuloendotheliosis.

Sinus histiocytosis with massive lymphadenopathy—Properties of cultured histiocytes

Abstract This paper describes the properties of cultured histiocytes derived from lymph node material of a patient with sinus histiocytosis. Before culture the cytoplasm of the histiocytes contained numerous leucocytes, residual bodies and large spherical membrane-bound inclusions of moderate electron density. After prolonged culture, these features disappeared from the cytoplasm. However, when buffy coat cells from a normal individual were brought in contact with the cultured histiocytes, they were phagocytozed and the residual bodies and the large spherical electron dense bodies then reappeared in the cytoplasm of the histiocytes.

The ultrastructural demonstration of virus-like particles in human leukaemic cells.

Abstract This ultrastructural study is concerned with the description of virus-like particles in the cytoplasm of primitive human leukaemic cells. Such virus-like particles are shown not to be confined to a particular type of leukaemia, being seen in acute granulocytic leukaemia, acute lymphocytic leukaemia, and blastic crisis of chronic myeloid leukaemia. The morphology and distribution of the particles is considered in relation both to previous ultrastructural studies of possible virus particles in human leukaemias, and to the possible association between oncogenic viruses and this group of malignancies. Since C-type viruses have been shown to be the causative agent in an increasing number of animal leukaemias, the possibility that the virus-like particles described in this paper represent incomplete C-type virus is discussed.

Membrane Receptors of Human Leukaemic Myeloid Cells: Sequential Expression of the γFc Receptor

Summary. An immunological surface marker study was performed on 13 patients with a variety of myeloid leukaemias. It was shown that expression of the receptor for the Fc of IgG (γFcR) starts to take place at the promyelocyte stage, and that the receptor is present on more mature granulocytic cells, but is absent from myeloblasts. Myeloblasts and promyelocytes are negative for the complement receptor CR2. Monoblasts, unlike myelobasts, were shown to express a γFcR and, to a lesser extent, CR2. Receptor expression therefore appears to be an earlier event in monocytic development. The possible diagnostic value of immunological marker studies in myeloid disorders is considered.

A- and C-type particles of mouse myeloma cells.

Abstract Electron microscopic examination of the P- 3 mouse myeloma cell line revealed that most cells contained a very large number of intracisternal A-type particles, while only a few C-type particles appeared to be produced. The C-type particle was readily isolated in 3 T 3 mouse fibroblast cells where its presence could be demonstrated both by the RIF test and by electron microscopy, which revealed numerous extracellular C-type particles, but no A-type particles. Since the P- 3 cells in contrast contained many more A-type than C-type particles, it is suggested that (1) intracisternal A-type particles are not precursors of C-type particles, (2) intracisternal A-type particles are not infectious.