Characterization of the two major species of slow reacting substance from rat basophilic leukemia cells as glutathionyl thioethers of eicosatetraenoic acids oxygenated at the 5 position. Evidence that peroxy groups are present and important for spasmogenic activity

The most prominent slow reacting substance from rat basophilic leukemia cells (type I) was characterized by radiochemical, chemical and physical methods and shown to contain a C20 unsaturated fatty acid oxygenated at the 5 position and a sulfur containing side chain in thioether linkage at the 6 position. Its spasmogenic action on guinea pig ileal muscle was largely inactivated under reducing conditions which suggested that a peroxy group was present and important for contractile activity. This was supported by ferrous thiocyanate analysis. The peroxy group is almost certainly at the 5 position, probably in the form of a peroxy ester or hydroperoxide. Based on amino acid hydrolysis (0.85 moles of glycine and 0.30 moles of glutamic acid per mole SRS), the sulfur containing side chain is apparently a mixture of glutathione and cysteinyl-glycine, but by chromatography the side chain is predominantly glutathione and the low yield of glutamic acid may be due to complexing of its alpha COOH group in a peroxy ester linkage. The fatty acid moiety has 3 conjugated double bonds, probably at the 7,8, 9,10 and 11,12 positions. Type II SRS, the second major species, differs in that the sulfur containing side chain is linked at the 12 or 13 position and is almost certainly glutathione and in the failure of alkaline borohydride to produce inactivation. These observations strongly implicate the lipoxygenase pathway in slow reacting substance biosynthesis.

Amplification of growth inhibition by glucocorticoid on L5178Y and L1210 lymphoblasts in vivo

One component of a factor in Proteus mirabilis (Factor 1) which specifically amplifies the induction of several liver enzymes by glucocorticoid in target cells also increases the growth inhibition of glucocorticoid on the ascitic form of L1210 cells and solid tumors of L5178Y lymphoblasts in vivo. The growth of L5U78Y and L1210 lymphoblasts was inhibited by a triamcinolone acetonide dose of over 0.5 to 1.0 mg/kg body weight. Factor 1 increased the inhibitory effect of a triamcinolone acetonide dose of less than 4.0 mg/kg bodyweight but had little effect on the effects of doses of over 4.0 mg. Factor 1 (10 biological units/kg body weight) itself also caused marked inhibition of the growth of these lymphoblasts without affecting the body weight or adrenal gland weight, its effect being equivalent to that of 3- to 4-mg/kg body weight doses of triamcinolone acetonide alone. There was no significant difference in the level of plasma total corticoids or that of plasma adrenocorticotropic hormone between rats treated with 0.9% NaCl solution or those treated with Factor 1, and Factor 1 had no cytotoxic effec on cultured L5178Y lymphoblasts. Thus, Factor 1 may amplify the effect of physiological level of glucocorticoid in mice sufficiently to inhibit the growth of these lymphoblasts without causing any significant side effects to the host animal.

Functional cell compartments in a rat model for human acute myelocytic leukaemia

Functional cell compartments were studied in a rat model for human acute myelocytic leukaemia (AML). This was done by tracing the distribution of injected 51Chromium-labelled leukaemic cells in the body. It was concluded that two functional compartments can be distinguished in acute leukaemia, i.e., a rapidly exchangeable pool of cells (including the circulating blood pool, the marginal noncirculating blood pool and the rapidly exchangeable tissue pool; RETP) and a slowly exchangeable tissue pool (SETP). The sizes of these various compartments were roughly quantified at various stages of the disease by calculations based on the principle of isotope dilution and organ weight measurements. As the leukaemia progresses, the size of the SETP increased significantly relative to the size of the RETP. Simultaneously, the exchange rates of leukaemic cells between the organs and the blood decrease. The blood transit time of leukaemic cells was also significantly prolonged, as is the case in human AML.

Friend virus production and heme synthesis in primary mouse spleen cell cultures

A cell culture method has been developed in which spleen cells from Friend virus (FV) infected mice can be studied for virus production as well as erythroid differentiation. Primary spleen cell cultures from plethoric Balb/c mice were initiated at 24, 48 or 73 h after FV infection. These cells manifested a well-defined wave of heme synthesis at approximately 64, 48, or 23 h, respectively, of cell culture. Assays for spleen focus-forming virus (SFFV) and helper murine leukemia virus (MuLV-F) production in these cultures revealed that the peak rates of production of both viruses occurred at essentially the same time as the peaks of heme synthesis. The time at which the peaks of virus production and heme synthesis occurred in vitro was related to the time interval after infection (80-105 h) rather than the time at which the cells were placed in cell culture or the number of hours of cell culture. Medium change experiments suggested that the temporal relation between heme synthesis and virus production was an intrinsic feature of FVP infected cells in this in vitro system.

Cultured human leukemic non-T/non-B lymphoblasts and their stimulating capacity in "one-way" mixed lymphocyte reaction: suggestive evidence for early T-cell or B-cell precursors

It is now well recognized that a large proportion of cases with acute lymphoblastic leukemia are classified as non-T/non-B neoplastic disease. The origin of leukemic non-T/non-B cells is at present not known. It has been shown that fresh or cultured leukemic T lymphoblasts exert no stimulating capacity while leukemic B lymphoblasts exert a strong stimulation in "one-way" mixed lymphocyte reaction. It has also been shown that fresh leukemic cells from some patients with non-T/non-B acute lymphoblastic leukemia possess a strong stimulation while leukemic cells from other patients with this disease possess no stimulation on allogeneic lymphocytes. The present study shows that cultured leukemic lymphoblasts from 3 non-T/non-B cell lines (NALL-1, NALM-6 and NALM-16) consistently exert a strong stimulation on allogeneic lymphocytes. On the other hand, cultured leukemic lymphoblasts from 2 non-T/non-B cell lines (REH and KM-3) consistently fail to stimulate in "one-way" mixed lymphocyte reaction. Our data clearly support the speculation that leukemic non-T/non-B cells which possess the stimulating capacity may represent less differentiated leukemic B lymphoid cells (pre-B cells) and leukemic non-T/non-B cells which possess no stimulating capacity may represent less differentiated leukemic T lymphoid cells (per-T cells).

Filtrability and flow characteristics of leukemic and non-leukemic tumor cell suspension through polycarbonate filters in relation to hematogenous spread of cancer

Tumor cell suspension was filtered through Nuclepore filters of various pore diameters (5.4, 7.9 and 9.3 micron) with positive pressure from 5 to 60 cmH2O at 37 degrees C. The mean diameters of tumor cells of 6 strains ranged from 10.6 to 13.6 micron. Cell suspension of each tumor strain was filtered with characteristically different time. No significant difference was observed among tumor strains in the percentage of cells filtered. The cell viability was almost unchanged by filtration. The filtration time was considered to indicate the passing ability of tumor cells through capillary pores. Leukemic cells such as DBLA 1, DBLA 6 and L 1210 were relatively small in diameter and possessed a high passing ability compared with other non-leukemic tumor cells such as Yoshida sacroma, AH 109A and AH 100B. The relationship between pressure and flow rate of the cell-free solution was linear, while the pressure-flow rate curves of the tumor cell suspension were convexed to the pressure-axis at low pressure and became linear over the pressure of the yield point. Rheologically, the yield point and the reciprocal of the slope indicate structural viscosity and apparent viscosity of the cell suspension, respectively, they are considered to reflect the rheological properties of tumor cells. Comparing these parameters of the curves in filters of different pore diameters, the viscosity of leukemic cells appeared to be the lowest and the structural viscosity of AH 100B cells was the highest among the tumor strains examined. The distribution and frequency of metastases following intravenous transplantation of these tumor cells suggested that the passing ability of tumor cells plays an important role in organ preference of hematogenous metastasis and leukemic state in leukemia.

Increased levels of lipid-bound sialic acid in thymic lymphocytes and plasma from leukemic AKR/J mice

Lipid-bound sialic acid levels for thymic lymphocytes and plasma were elevated twofold in leukemic AKR/J mice as compared to the levels observed in young, nonleukemic mice. In contrast, lipid-bound phosphorus levels were similar for thymic lymphocytes from both groups of mice.

Non-specific and specific effects of a granulocytic bio-inhibitor on different haematopoietic cell populations

The effect of a leucocyte conditioned medium derivative on the 5-125iodo-2'-deoxyuridine (125I-UdR) uptake by 6 haematopoietic cell populations with a simple in vitro assay system was tested. The low doses of the test substance--a putative granulocytic chalone--inhibited significantly the uptake of 125I-UdR only in predominantly granulocytic cell cultures. This inhibition was achieved using micrograms/ml concentrations, which have previously been shown to be inhibitory to normal and malignant granulocytic cells in vivo. The test preparations inhibited the uptake of 125I-UdR in all cell populations (nongranulocytic included) when doses exceeding 10 micrograms/ml were used. The prerequisite for an adequate demonstration of the specificity of a bio-inhibitor is discussed.

[Blood histamine level in chronic myeloproliferative diseases; a review]

Since the discovery of a very high blood histamine level in chronic myelocytic leukemia (CML) 1936, the author could ascertain that this parameter is very useful in the differential diagnosis between CML and various "leukemoid" reactions; in the early diagnosis of CML and in the differential diagnosis between CML and other myeloproliferative disorders. Recent researches proved that no correlation exists between blood histamine level and basophil count in the peripheral blood. Further investigations in this field have to clear up the questions whether it is possible by means of repeated controls of the blood histamine level to predict the development of a polycythemia vera into CML or to establish in a case of osteomyelosclerosis that this disease has been Preceeded by A CML.

Acute monocytic leukemia in an irradiated Beagle

A purebred female Beagle dog that had received 2,000 R of protracted wholebody gamma-irradiation from 60Co when 14 months old had hematologic changes consistent with a myeloproliferative disorder 3 years after the termination of radiation exposure. Peripheral blood and bone marrow findings during the 7-month period before death showed progressive anemia with increased numbers of platelets; immature granulocytes, monocytes and promonocytes. A period of partial remission occurred during which time the peripheral blood was aleukemic, although there was marked thrombocytosis and abnormal erythropoiesis which was evidenced by bizarre circulating nucleated red cells, anisocytosis, poikilocytosis and Howell-Jolly bodies. The dog had a terminal crisis with marked leukocytosis, most cells in the peripheral blood being bizarre monocytes and promonocytes. Tissues obtained at necropsy showed diffuse as well as focal infiltration of the spleen, liver, lymph nodes, heart, kidney and gastrointestinal wall with immature neoplastic cells resembling monocytes and monocytic precursors. The monocytic differentiation of the invasive cell population was confirmed by morphological, cytochemical, histological, ultrastructural and in vitro cell culture studies.

Induction of erythroid differentiation in murine erythroleukemia cells by N-substituted polymethylene diamides

Various N-substituted polymethylene diamides were synthesized and tested for their potency to induce erythroid differentiation in murine erythroleukemia cells. N,N,N',N'-tetramethyl-1.6-hexane-dicarboxamide (IIc) was the most potent inducer among 15 compounds tested. The effectiveness of this compound was similar to that of hexamethylene bisacetamide (HMBA). HMBA has a different amide linkage order from that of IIc. HMBA and IIc at a concentration of 5 mM had similar effects on the cell growth rate and induced a similar frequency of benzidine-positive cells. However, hemoglobin production was 1.5 times more effective with IIc. Polymethylene diester, diamide, dihydrazide and dianilide had no effect on the induction of hemoglobin synthesis. The N-alkylated amide group appears to be required for induction of differentiation in murine erythroleukemia cells.

Identification of a non-H-2 gene (Rfv-3) influencing recovery from viremia and leukemia induced by Friend virus complex

The dominant C57BL/10 allele of a single autosomal, non-H-2 gene (Rfv-3) was found to be required for recovery from viremia and leukemia induced by Friend virus complex in H-2b/b mice. In H-2a/a mice, the Rfv-3 gene apparently influenced recovery from viremia in the presence of persistent leukemia because these mice lacked the appropriate H-2 genotype for recovery from leukemia. The Rfv-3 gene was distinct from the Fv-2 gene because recovery from viremia was seen in recombinant-inbred mice with the Fv-2s/s genotype. Furthermore, backcross studies indicated that Rfv-3 and Fv-2 were not linked. The Rfv-3 gene may act by influencing the specific anti-FV humoral antibody response.

Effect of phenobarbital on plasma levels of cyclophosphamide and its metabolites in the mouse

We have studied the quantitative pharmacokinetic differences of individual metabolites and unchanged cyclophosphamide (CPA) in control and phenobarbital-treated animals, using radiolabelled CPA together with thin-layer chromatography. On Day 0, one group was started on phenobarbital drinking water and one group stayed on regular acid water. P388 leukaemia, (10(6) cells i.p.) was administered to all mice on Day 8, and 2 days later both groups of mice were given i.p. CPA (200 mg/kg) with 14C-CPA (0.2 muCi per mouse). At 5--60 min after CPA administration, groups of 10 mice were killed and their blood collected for assay of parent compound and metabolites in plasma. Phenobarbital pretreatment reduced CPA and phosphoramide mustard CXT (concentration x time) by 66+% and 27+%, respectively. Assuming that phosphoramide mustard is both the ultimate cytotoxic form of CPA and the blood-transport form, the reduction of CPA by phenobarbital would predict a decreased therapeutic effect. The assay methods in this study will be used in the future to determine the importance of this potential drug interaction in man.

Inhibition of normal murine hematopoiesis by leukemic cells

Inhibition of normal mouse hemopoietic stem cells by leukemic cells (C1498) was observed with use of in vitro agar and in vivo diffusion-chamber cultures. The C1498 cells were unresponsive to colony-stimulating activity, and, above a critical threshold, they inhibited normal granulocyte progenitors in agar culture. C1498 cells added to normal marrow in diffusion chambers progressively reduced granulocyte progenitors. The larger, more rapidly growing, C1498 cells showed the most inhibitory effect. Transmembrane culture of C1498 cells adjacent to normal marrow in double diffusion chambers for five to 14 days led to reduction of recovery of granulocyte progenitors (72 +/- 7 per cent of control) and pluripotent stem cells (45 +/- 7 per cent of control) from the normal marrow chambers. These results indicate that leukemic mouse cells inhibit normal mouse-marrow stem cells by releasing a diffusible substance, and this inhibition occurs primarily at the level of the pluripotent stem cell.

Hematogenous development of rat mature granulocytic leukemia--comparison of 2,7-FAA-induced and transplanted leukemia

The oral administration of N,'N-2,7-fluorenylenebis-acetamide (2,7-FAA) induces leukemia, especially mature granulocytic leukemia in rats. We compared the degree of infiltration of 2,7-FAA-induced mature granulocytic leukemia with that of transplanted leukemia for the purpose of proving hematogenous development of leukemia. The bone marrow, spleen and liver were examined in the cases of diffuse lesion of 2,7-FAA-induced and transplanted leukemia. The average degree of infiltration of both 2,7-FAA-induced and transplanted leukemia was high in the bone marrow, medium in the spleen, and low in the liver. Intravenous transplantation of malignant neoplasm is an example of hematogenous metastasis. The similarity of infiltration between 2,7-FAA-induced and transplanted leukemia suggests that the former is spread by hematogenous metastasis.

[Identification and properties of proteins characteristic of the Shvets rat leukosis]

Blood proteins were examined in rats with the Shvets experimental leukosis positively reacting in the sedimentation test for leukosis. Application of monospecific antisera against main classes of immunoglobulins shows that this protein belongs to immunoglobulins of the class G. The sedimentation constant and molecular weight of the protein under study are determined. It is shown that immunoglobulin G of rats with leukosis activates glycolysis and inhibits respiration. The data obtained give reasons to assume not complete identity but, in any case, similarity of physicochemical properties of proteins appearing in animal and human blood channel with malignant growth.