RS Cells Research Articles

Role of S gene of bacteriophage lambda in host lysis

Using E. coli lysogens carrying heat inducible λ defective in R or S or both R and S genes (called R, S and RS cells respectively), it has been found that induced β-galactosidase synthesis by host continued in S cells beyond the normal time of lysis. S function affected the permeability of host cell membrane. When radioactive labelled host membrane was incubated in vitro with extracts prepared from phage induced R and RS cells, R cell extract solubilized labelled lipid mostly in the undegraded form. This indicated that S gene product may be a lipophilic protein rather than a phospholipase.

PH mediated inhibition of the cell to cell spread of herpes simplex virus infection.

The relationships between the environmental pH and the replication and spread of herps simplex virus (HSV) infection in rabbit skin (RS) cell cultures was studies. Relative to the plaque formation at pH7.0, incubation of RS cells with medium adjusted to pH 6.6 resulted in a 50 to 70 per cent decrement in plaque number. The addition of overlay media adjusted to pH 6.0 or 6.3 precluded HSV plaque formation. Select HSV-1 (type 1) and HSV (type 2) strains readily survived a 3 day incubation with medium adjusted to pH 6.3 as demonstrated by plaque production following a medium shift to pH 7.0. Rs cells incubated with medium at pH 6.3 did not replicate. The survival of RS cells incubated for 3 days with medium adjusted to pH 6.3 was demonstrated by renewed cell proliferation following a medium change from pH 6.3 to 7.0. The progeny virus yields of two HSV strains replicating in RS cells incubated with medium adjusted to pH 6.3 or 7.0 were equivalent at 24 or 48 hours post infection and were indicative of a productive infection. The inhibition of HSV plaque formation at pH 6.3 was not due to an alteration of cell receptors but was the result of an inhibition in the cell to cell spread of the virus. These results are discussed with regard to the possibility that the decline in pH associated with the inflammatory response may serve as a host defense against HSV infections.

Hairy cell leukemia ('leukemic reticuleondotheliosis'), reticulosarcoma, and monocytic leukemia. Cytochemical and ultrastructural investigations.

Cytochemical and electron-microcopic studies have been carried out on leukemic monocytes and 'hairy cells' (HC), 'reticulosarcoma' (RS) cells and cells of cases of 'reticulosis' and 'reticulosarcoma cell leukemia'. Additional investigations included equantitative determinations of the urinary lysozyme excretion, skin window studies, testing of the phagocytosis of ferritin by HC, and labelling of the Fc receptors on CH at the ultrastructural level. Clear evidences against any cytological relationship among leukemic HC and monocytes have been provided. Further results argued also against the frequently stressed relationship among leukemic monocytes and RS cells. Cases of 'RS cell leukemia' and 'reticulosis' had to be reclassified as lymphosarcoma cell leukemia, acute lymphatic, and myeloblastic leukemias. Besides distinct ultrastructural differences among HC, RS cells, and lymphocytes, mainly gradual differences have been noted using cytochemical methods and by evaluating the phagocytosis of ferritin particles. A further common trait of HC, RS cells, and B lymphocytes seems to be the presence of surface Fc receptors. A more precise classification instead of the diagnosis 'reticulosarcoma' and 'reticulosarcoma cell leukemia' is required, and the use of the term 'hairy cell' leukemia is suggested stead of the misleading term 'leukemic reticuloendotheliosis'.

On Completing Latin Rectangles

By an (incomplete) r × s latin rectangle is meant an r × s array such that (in some subset of the rs cells of the array) each of the cells is occupied by an integer from the set 1, 2, …, s and such that no integer from the set 1,2, …, s occurs in any row or column more than once. This definition requires that r≦s. If r=s we will replace the word rectangle by square. It is easy to see that for any n≧2 there is an incomplete n × 2n latin rectangle with 2n cells occupied which cannot be completed to a n × 2n latin rectangle. In this paper we prove the following theorem.Theorem 1. An incomplete n × 2n latin rectangle with 2n—1 cells occupied can be completed to a n × 2n latin rectangle.

Progress in Experimental Tumor Research, Vol 7.

This publication contains seven reviews compromising a total of 351 pages. The first review by L. A. Zilber from the Gamalaya Institute, Moscow, on the Pathogenicity and Oncogenicity of Rous Sarcoma Virus begins with an excellent historical review on RSV. A detailed description is presented of the characteristics of the cysts, hemorrhagic and tumor lesions induced by RSV. The oncogenic action of Rous virus in rats, cotton rats, mice, rabbits, Syrian hamsters, Chinese hamsters, guinea pigs, and monkeys is described. Artificial immunologic tolerance by RSV and transformation of mammalian cells in vitro by RSV are discussed. Svoboda's experiments for the production of XC-tumor by intraperitoneal transplantation of RS cells in newborn rats, the production of tumor P following the injection of cellular material of Prague strain into newborn hamsters, and the demonstration of viral antigen in cysts and tumors induced by RSV in mammals were fascinating discussions. The author concludes

Differentiation of glucose-6-phosphate dehydrogenase isozymes and morphogenesis in Blastocladiella emersonii.

Studies were made of some of the properties of a NADP-specific Glucose-6-phosphate dehydrogenase present in the OC and RS cells of the aquatic fungus, Blastocladiella emersonii, the former harvested at their generation time and the latter at their morphological point of no return. A more detailed analysis was then made of the distribution of soluble and bound forms of the dehydrogenase during the exponential growth and subsequent differentiation of the RS cell, as well as the changes which occurred in the isozymes of this enzyme during the same developmental period. The results, together with some related, previously published work, were discussed with emphasis on the relation between biochemical and morphological differentiation in B. emersonii.