The acute erythroleukemia induced in mice by the anemia-inducing strain of the Friend virus complex is caused to regress by normal macrophages. We examined the possibility that reversal of leukemia is related to a macrophage regulatory function in erythropoiesis. We found that the ability of macrophages to induce leukemia regression correlates with nonimmunological, in vivo suppression of norma...

Previous investigations have demonstrated the existence of an autonomous intranuclear inositide cycle endowed with conventional lipid kinases and phospholipase C (PLC) which is the isoform beta in Swiss 3T3 cells, PC12 pheochromocytoma cells, human osteosarcoma SaOS-2 cells, and rat liver. The presence of PLC has been investigated in nuclei of Friend erythroleukemia cells. Both beta and gamma i...

An NFS/N mouse inoculated at birth with an ecotropic murine leukemia virus (MuLV) obtained from wild mice (Cas-Br-M MuLV) developed a lymphoma after 18 weeks. An extract prepared from the lymphomatous spleen was inoculated into newborn NFS/N mice, and these mice developed erythroleukemia within 9 weeks. Spleens from the erythroleukemic mice contained ecotropic and mink cell focus-inducing (MCF)...

P ARAPROTEINS* ARE generally found in the serum in patients suffering from multiple myeloma or Waldenstr#{246}m’s macroglobulinemia. Recently, however, there have been a number of reports on patients in whom paraproteinemia#{176} was found in association with a myeloproliferative disorder such as polycythemia, erythroleukemia, acute myeloblastic and lymphoblastic leukemia, and chronic myelocyti...

57-year-old man was admitted to our Institute with a two-week history fever up to 39°C, hepatomegaly and splenomegaly. Hematological findings were as follows: Hb 8.8 g/dL, platelet count 193310/L, WBC 54310/L with neutrophils 12%, lymphocytes 8%, blasts 80%, nucleated red blood cells 65/100 WBC. The immunological studies carried out by flow cytometry showed that circulating blasts were CD2, CD7...

Mice inoculated with the RFV strain of Friend virus develop an erythroleukemia that spontaneously regresses. Bone marrow cells from leukemic mice produce a factor that inhibits colony formation in agar by normal CFU-Cs. CFU-Cs from leukemic animals are resistant to the factor. Bone marrow cells from some mice whose leukemia has regressed continue to produce the factor, and CFU-Cs from some regr...

Stable human leukemia-lymphoma cell lines provide model systems to study the processes involved in leukemic and normal cell differentiation [10]. Leukemic cells, arrested at a certain stage of differentiation, can be triggered to differentiate to functionally and morphologically more mature cells [7]. Both "fresh" leukemic cells and cells maintained in long-term culture are sensitive to in vitr...

T HE DI GUGLIELMO SYNDROME1 is a condition characterized principally by neoplastic proliferation of the cells of the erythroid series, which is frequently, if not invariably, associated with leukemic proliferation of the cells of the granulocytic series. It is usually of acute variety but-rarely-chronic forms are encountered. The term “acute erythremic myelosis” or “Di Guglielmo disease”2 is fr...