Nonspecific suppressive effect of Ehrlich tumor ascitic fluid on transplantation immunity]

The influence of syngeneic Ehrlich ascites tumour fluid on the survival of allogeneic skin allografts was investigated on CC57BR mice. A 3--4-day delay of the allograft rejection in mice injected with ascitic fluid was revealed. Preliminary transplantation of such allograft to mice with Ehrlich tumour produced no intensification of the immunodepressive action of the ascites fluid obtained from them. The data obtained indicated the preferential significance of the antigen-independent immunosuppressive factors of ascites tumour fluid in the suppression of the transplantation immunity in vivo.     

The modelling of the growth of Ehrlich carcinoma and teratoma T-36 with ascitic fluid and tumor-cell dialysate]

The study of the effect of ascitic fluid and dialysate of Ehrlich ascites tumor cells (M.m. less than 15 kDa) on the growth of Ehrlich carcinoma and teratoma T-36 has shown that both the ascitic fluid and dialysate can protect tumor cells in vivo. The number of animals with tumors increased from 0% in control animals to 60 and 20%, respectively, in experimental ones after transplantation i.m. of 20 x 10(3) Ehrlich tumor cells into mice. Compared to control, ascitic fluid and dialysate of Ehrlich ascites tumor cells increased the rate of tumor growth to 195 and 153%, respectively. It is suggested that this test-system simulates the effect of tumor humoral factors in vivo.     

Physical studies on glycoproteins from ascitic fluid of Ehrlich ascites tumor.

Three glycoproteins, designated as F, M and S glycoproteins were identified in the HCIO4-soluble fraction of ascitic fluid of Ehrlich ascites tumor by 8% polyacrylamide disc gel electrophoresis. They were separated and purified as described previously (Reznick, A.Z. and Winzler, R.J. (1973) Fed. Proc. 32, 368 and Reznick, A.Z., Allen, H.J. and Winzler, R.J. (1973) Anal. Biochem. 52, 395-401) and subjected to physical characterization. Several physical properties such as molecular weights, sedimentation and diffusion coefficients, partial specific volumes, Stoke's radii and frictional ratios were determined. The physical parameters of F and S glycoproteins resemble data that have been reported for orosomucoid and haptoglobin-like glycoproteins, respectively. Properties of M glycoprotein could not be associated with a known glycoprotein.     

The effect of ascitic fluid globulins on the growth of leukemia P388/DOX and Ehrlich's carcinoma in mice]

The study was performed to investigate the effect of ascitic fluid globulins of tumor on tumor growth and life span of mice. The globulins are shown to shorten the life span of Ehrlich tumor mice from 86.8 to 61.8 days, to increase 3-5-fold the growth rate of Ehrlich carcinoma and P388/DOX tumor. It was found that globulins of ascitic fluids and serum globulins of tumor have equal effects of tumor growth. It is proposed to use globulins of ascitic fluid to study the globulin role in tumor growth.     

Glycoproteins from ascitic fluid of Ehrlich ascites tumor: Isolation and chemical characterization

Three glycoprotein bands were identified by polyacrylamide disc gel electrophoresis in the perchloric acid soluble fraction of ascitic fluid of Ehrlich ascites tumor in mice. The three proteins were first separated by a new discontinuous preparative electrophoresis apparatus described previously [1]. They were further purified on Sephadex G-100 and then were subjected to chemical characterization. These glycoproteins were rich in glutamic and aspartic acids and contained the sugar moieties galactose, mannose, fucose, N-acetyl-D-glucosamine and sialic acid. The percent sugar composition ranged from 17.7–37.3% of the total weights of these glycoproteins.     

Comparative radiosensitivity of clonogenic tumor cells of the transplantable Ehrlich carcinoma in the ascitic and solid forms of growth

Survival of clonogenic cells of solid Ehrlich ascites tumor (EAT) exposed to 60Co-gamma-radiation in vitro under the oxygenation conditions was investigated and the clonogenic capacity and radiosensitivity of these cells and cells of the previously studied EAT ascitic form and Lewis solid tumor comparatively studied to elucidate how the efficiency of colony formation (ECF) would affect their radiosensitivity. ECF for solid EAT cells was 2.6 +/- 0.3%, which was lower, by about an order of magnitude, than that for ascitic form of this tumor and was nearly the same as that for Lewis tumor cells. A median cell lethal dose (D0) was practically the same for all tumors under study. It is suggested that the differences in ECF do not substantially influence the radiosensitivity of clonogenic cells of the studied tumors.     

The comparison of an acidic glycopeptide from the ascitic tumor fluid and of the glycopeptide from Ehrlich cells

An acidic glycopeptide of molecular weight of 12000 daltons and of pI 5.6 from the ascitic tumor fluid of Ehrlich cells was isolated and characterized with regard to its physico-chemical properties and compared with an acidic glycopeptide of Ehrlich cells. Both glycopeptides have the same carbohydrate and amino acid components but differ in respect of quantity. The origin of an acidic glycopeptide from the ascitic tumor fluid of Ehrlich cells is briefly discussed.     

Glycoproteins from ascitic fluid of Ehrlich ascites tumor. Isolation and chemical characterization.

Three glycoprotein bands were identified by polyacrylamide disc gel electrophoresis in the perchloric acid soluble fraction of ascitic fluid of Ehrlich ascites tumor in mice. The three proteins were first separated by a new discontinuous preparative electrophoresis apparatus described previously [1]. They were further purified on Sephadex G-100 and then were subjected to chemical characterization. These glycoproteins were rich in glutamic and aspartic acids and contained the sugar moieties galactose, mannose, fucose, N-acetyl-D-glucosamine and sialic acid. The percent sugar composition ranged from 17.7-37.3% of the total weights of these glycoproteins.     

The synchronizing effect of cyclic 3',5'-adenosine monophosphate on the mitotic cycle of Ehrlich ascitic carcinoma cells]

A study was made of the number of mitoses and of the DNA-synthesizing cells in the ascitic Ehrlich carcinoma in the course of 24 hours after the injection of cyclic 3',5'-adenosinmonophosphate to mice. It was found that as the result of the preprrophase inhibition and, possibly, of stimulation of the cell entry into the S-phase, 8 hours after the action a great number of cells began to divide almost simultaneously. The effect of mitosis synchronization was assessed in the tumour cell population.     

Effect of colchamine on Ehrlich ascitic carcinoma cells showing synchronized cell division]

The author studied the 24-hour changes in the number of normal and colchamine mitoses in the cells of Ehrlich's ascites carcinoma in mice after the injection of colchamine argainst the background of partial synchronization of cell division, obtained as a result of preliminary injection of dibutyryl cyclic 3',5'-AMP, and also in mice after the injection of colchamine alone or dibutyryl cyclic 3',5'-AMP. As shown, synchronization of cell division in the tumour led to the 2,6-fold increase in the number of tumour cells blocked by colchamine and also to the accelerated arrest of colchamine mitoses.     

Effect of mouse interferons on the development of Ehrlich ascitic carcinoma

Intraperitoneal injection of various preparations of mouse interferons (L cell tissue culture interferons, concentrated or partly purified, and also serum interferon) significantly inhibited the development of Ehrlich's ascites carcinoma in randombred mice. In view of comparatively low activity of serum interferon, the effect of normal mouse serum on the tumour development and its action on L cell tissue culture interferon was investigated. It was shown that normal mouse serum inhibits the action of L cell tissue culture interferon and promotes the development of Ehrlich's ascites carcinoma.     

Effect of an extract of mouse Ehrlich ascitic tumor cells on mitotic activity and DNA synthesis in that tumor]

The extract of Ehrlich's ascitis tumour cells depressed specifically the proliferative activity of this tumour cells. This was expressed in a marked reduction in the number of dividing and DNA-synthesizing cells after the extract injection. The mitotic index fell considerably as soon as 2 hours after the injection, reached the minimum in 4 to 5 hours and was restored to the control level in 9 to 12 hours. The radioactive index appeared to be evenly decreased in the course of 18 hours of the experiment.     

The effect of membrane-active compounds on the radiation-modifying effect of glucose in x-irradiated ascitic tumor cells]

A study was made of the influence of membrane-active agents with different mechanisms of action (quercetin, amiloride, valinomycin, and digitonin), that modify the transmembrane transfer of inorganic ions, on a modifying effect of a glucose loading in X-irradiated Ehrlich ascites tumor cells. The combination of digitonin with glucose increased the damaging effect of radiation on tumor cells by 1.8-2.2 times as compared to glucose alone. Merely insignificant changes in the radiation-modifying effect of glucose were observed when it was combined with other membrane-active agents.     

Studies on the cholinesterase forms present in the ascitic fluid of Ehrlich tumour.

Cholinesterase activity was detected in the ascitic fluid of Ehrlich tumour and studied in a comparative manner in relation to that found in mice plasma. Enzymes from both sources were characterized with respect to optimum pH, substrate concentration and quinidine inhibition. After gel filtration by Sephadex G-200 and Sepharose 6B, two enzyme forms were observed in ascitic fluid as well as in mice plasma: a large form (L) and a small form (S) presenting molecular weights of 191 000, and 224 000 daltons for L forms and 71 000 and 69 000 daltons for S forms respectively. Concanavalin A interacts with both molecular forms, suggesting a glycoprotein nature for these enzymes.     

Effect of cycloheximide, 2,4-dinitrophenol and papaverine on ribosomal RNA synthesis in Ehrlich ascitic carcinoma cells]

The influence of 2,4-dinitrophenol (DNP), papaverine and cycloheximide on RNA synthesis in Ehrlich ascites tumour cells has been investigated. All above mentioned agents inhibit selectively synthesis of high-molecular rRNA precursor, when the cell population density is 3.10(7)--5.10(7) per 1 ml of suspension. When the density of cells decreases as far as 1.10(6) cells per 1 ml. the rRNA synthesis loses the sensitivity to all these agents. The effects of both cycloheximide on the protein synthesis and DNP on ATP level do not depend on the cell population density in suspension. It is suggested that either with a decrease of cell population density the protein synthesis and ATP level cease playing the role of a rate-limiting factor in the rRNA synthesis, or the influence of agents studied is realized by means of their interaction with other cell system.