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This study examined the effects of retinoic acid (RA) on [14C]acetate incorporation and fatty acid composition of hamster embryo fibroblasts (HEF) and two cell lines derived from the same inbred strain but transformed by herpes simplex-2 virus (HSV) or polyoma virus (HFT). Cells were exposed to all trans RA, or dimethylsulfoxide (DMSO), the vehicle for RA, and the lipids labeled with [14C]acetate. Lipids were extracted from the cells, separated by paper chromatography, located by autoradiography, and acetate incorporation determined by liquid scintillation spectrometry. The distribution of fatty acids in total cell lipids was examined by gas chromatography. HEF cells incorporated more acetate into cholesterol than either transformed cell type. The HFT line incorporated more acetate into triglycerides and less into total phospholipids than either the HSV line or the HEF line. RA caused a significant decrease in incorporation of acetate into cholesterol and sphingomyelin in all three cell lines. HEF and HSV cells had decreased incorporation into phosphatidyl inositol-phosphatidyl serine and increased incorporation into triglycerides, changes not evident in the HFT cell. The control fatty acid profiles of the HEF and HSV cells were similar, while the HFT cells had a larger proportion of C16:0 and 18:1 fatty acids. Following treatment with RA all three cell types showed an increase in palmitic and a decrease in oleic acids. The three related cell types showed different [14C]acetate labeling patterns which did not respond uniformly to RA. On the other hand, exposure elicited some like responses in all cell types.

Use of cell electrophoresis combined with specific enzymes and varying ionic strength revealed a topological change of acidic sugars in lymphocyte membrane treated with a T-cell mitogen, phytohemagglutinin (PHA). The suggested alterations were an early translocation of hyaluronic acid to the cell periphery within 15 min of PHA addition and, 4 h later, the appearance of chondroitin sulphate in T-lymphocytes, but not in B-lymphocytes. As the contribution of chondroitin sulfate to the electrophoretic mobility increased with time up to 24 h, that of sialic acid decreased conversely. Several agents which block blast formation (2 mM ethylene glycol bis-β-aminoethylethyl-N,N,N′,N′-tetraacetic acid, 2 × 10−7 M ouabain, 0.1 μg/ml colchicine and 1 μg/ml cytochalasin B) also blocked the translocation of hyaluronic acid at the same concentrations. Chemical analysis of [14C]glycosaminoglycans by means of gel filtration followed by paper chromatography revealed a four-fold enhancement of the biosynthesis of chondroitin sulfate C after PHA stimulation. The presence of chondroitin sulfate in the cell periphery was also detected electrophoretically in T-cell type leukemia cells (MOLT-4B). These results suggest that the reorganization of glycosaminoglycans may be one of the membrane changes associated with blast formation of lymphocytes.

The pH-mobility relationships for standard saline washed Ehrlich ascites tumour cells before and after treatment with trypsin, neuraminidase and lower aldehydes have been examined. The supernatant fluids removed from neuraminidase-treated cells have been assayed by the Warren method for sialic acids and the supernatant fluid removed from trypsin-treated cells examined by paper chromatography; these analytical results have been correlated with the electrokinetic data. It is deduced that the surface of the Ehrlich ascites tumour cell examined bears at least three ionogenic systems, a carboxyl group of a sialic acid, which has a pK about 2.8, an unidentified acidic group(s), of pK about 3.5–4.0, and a basic group of pK about 10.

Summary HeLa (S3 clone) cells, bovine lymphosarcoma cells, monkey heart cells, and chick embryo endothelium cells were grown on Hanks' balanced Salt Solution supplemented with lactalbumin hydrolysate and bovine serum plus H32PO4 =. The various cell lines were labeled with inorganic 32P for varying periods of time. The phosphatides were extracted and deacylated with 0.1 N methanolic KOH at 37°C for 15 min. The deacylated phosphatides were separated by two-dimensional paper chromatography. The total phosphatide relative activity (cpm/wt protein/μg 32P applied) was determined at various times. The percent of the total phosphatide activity with time for each phosphatide was also determined. The phosphatide relative activity-time relationships demonstrated that each of the four cell lines studied varied in their phosphatide relative activities. This determination allows identification of these cell lines grown in culture. The ratio of relative activities of 32P-phosphatides to 32P-organic compounds indicated that phosphorus was utilized in the HeLa cell line preferentially for the synthesis of phosphorus compounds other than phosphatides. These other phosphorus compounds may be nucleic acids. Determinations of the per cent of total phosphatide activity for individual phosphatides in three cell lines presented evidence of a common biosynthetic pathway for phosphatides. Biosynthetic interrelationships of phosphatides were postulated to satisfy the sequential labeling of those phosphatides in both plants and animals. It was impossible to distinguish any basic difference between malignant and normal cells in culture by the procedures employed herein.

Summary By means of paper chromatography and the Feulgen reaction the effects of reserpine and amphetamine on the pteridine pattern and nuclear morphology were studied in the liver of Triturus cristatus . It was demonstrated that the Feulgen stainability and state of aggregation of chromatin, as well as the pteridine pattern can be altered by the influence of these drugs. From the results obtained it is suggested that the observed changes in nuclear morphology are due to the interaction of the drugs with the pteridine metabolism.

Chemotaxis of human neutrophil leukocytes moving on or in aligned 3D fibrin gels is more efficient if the cells are moving along the axis of fibre alignment than if they have to cross the fibres. This was shown by using two assays, one in which the cells were responding to a distant (600 micrometers) gradient source diffusing from a filter paper impregnated with formyl-Met-Leu-Phe and incorporated into the gel, the other in which the cells were responding to nearby (20--30 micrometers) Candida albicans spores in serum. In the former assay, impairment of chemotaxis across the axis of fibre alignment was highly significant. In the latter, cells showed efficient chemotaxis to the spores, but took more irregular paths when crossing the aligned fibres than when running along them. Neutrophils show contact guidance in aligned collagen or fibrin gels (Wilkinson et al., Exp cell res 140 (1982) 55) [1], thus the cells were subjected simultaneously to two directional cues in these experiments, one the chemotactic gradient and the other a contact guidance field. These cues may reinforce or interfere with each other depending on their relative orientation. Since many tissues in vivo show alignment or more complex forms of patterning, tissue architecture is likely to be an important determinant of the efficiency of cellular mobilization in inflamed or infected sites.

Basic quinone-imine dyes were tested for their effect in producing respiration-deficient mutants of baker's yeast. Some dyes of a subclass, azine dyes (Table I) were found to be effective, but neutral red was ineffective. Janus green B, which is ordinarily classified as an azo dye, was also tested and found to be strongly effective. Oxazine and thiazine dyes so far tested (Table II) were ineffective except one. This exception was Nile blue, an oxazine dye, of which a preparation from Grubler was strongly effective, while those from Tokyo Kasei and Merck were only weakly effective. The dyes were examined by paper chromatography. Development with acetone-water (4:6) and tert. -butanol-acetic acid-water (4:1:5) gave fairly good results. A few dyes were satisfactorily pure, but many others separated into two or more components. Efficacy of the dyes to produce the respiration-deficient mutants in relation to the chemical properties was discussed.