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21.
Claudio Fortis Elisabetta Ferrero Mauro Biffi Silvia Heltai Carlo Besana Eraldo Bucci Moreno Tresoldi Claudio Rugarli 《Cancer immunology, immunotherapy : CII》1991,34(2):128-132
Summary Burkitt lymphoma (BL) lines can be grouped according to phenotypic characteristics. Group I cells exhibit the phenotype of resting B cells and grow as single cells. Such lines can be Epstein-Barr-virus(EBV)-negative or -positive. Group II and group III cells are always EBV-positive, they express B cell activation markers, grow in aggregates and resemble in varying degrees lymphoblastoid cell lines (LCL). We studied three groups of BL lines for their capacity to interact with allogeneic lymphocytes. The results showed that as long as the lines have the group I phenotype, they do not stimulate allogeneic T lymphocytes irrespective whether they carry the EBV genome. The group II and III cells are stimulatory. Generally there was no correlation between sensitivity to lymphocyte-mediated lysis and the phenotype of the lines. In one set of lines, the group I cells had higher sensitivity to both natural killer and lymphokine-activated killer effectors compared to the group II or III lines. However, such correlation could not be seen with the other two sets of lines. Among the phenotypic features investigated, expression of the adhesion molecules LFA-1 and LFA-3 correlated with the tendency for cell aggregation. 相似文献
22.
Biochemistry and expression of myelomonocytic antigens 总被引:11,自引:0,他引:11
S M Goyert E M Ferrero S V Seremetis R J Winchester J Silver A C Mattison 《Journal of immunology (Baltimore, Md. : 1950)》1986,137(12):3909-3914
Six monoclonal antibodies (MAb) which react with myelomonocytic cells representing various stages of differentiation, and which precipitate six different cell surface molecules, were identified. A 50 to 55 kilodalton (Kd) glycoprotein, restricted in expression to mature cells of the monocyte lineage, was detected by immunoprecipitation with antibody MoS39. By using COS-7 cells transfected with a cDNA clone encoding the MoS39 antigen, various well-described anti-monocyte MAb, including Mo2, My4, Leu-M3 (MoP9), MoP15, MoS1, and 63D3, also bound to MoS39-expressing COS-7 cells, suggesting that this group of antibodies reacted with the same glycoprotein. Immature cells of the myelomonocytic lineage were shown to express two distinct molecules: one with an m.w. of 26 to 28 Kd identified by antibody SG133, and the second, a 130 to 140 Kd glycoprotein identified by MoU26. Mature granulocytes were found to express a 60 Kd molecule identified by antibody SG185 which was absent from other cells of this lineage. Two other molecules were shown to be present on both mature and immature cells of the granulocytic and monocytic lineages: a 130 to 140 Kd glycoprotein identified by antibody SG134, and a 160 to 170 Kd glycoprotein recognized by antibody MoU48. 相似文献
23.
Shawn Doonan Filippo Martini Sebastiana Angelaccio Stefano Pascarella Donatella Barra Francesco Bossa 《Journal of molecular evolution》1986,23(4):328-335
Summary We report here the complete amino acid sequences of the cytosolic and mitochondrial aspartate aminotransferases from horse heart. The two sequences can be aligned so that 48.1% of the amino acid residues are identical. The sequences have been compared with those of the cytosolic isoenzymes from pig and chicken, the mitochondrial isoenzymes from pig, chicken, rat, and human, and the enzyme fromEscherichia coli. The results suggest that the mammalian cytosolic and mitochondrial isoenzymes have evolved at equal and constant rates whereas the isoenzymes from chicken may have evolved somewhat more slowly. Based on the rate of evolution of the mammalian isoenzymes, the geneduplication event that gave rise to cytosolic and mitochondrial aspartate aminotransferases is estimated to have occurred at least 109 years ago. The cytosolic and mitochondrial isoenzymes are equally related to the enzyme fromE. coli; the prokaryotic and eukaryotic enzymes diverged from one another at least 1.3×109 years ago. 相似文献
24.
Nucleid acid metabolism in the LAM of the rat, both before and after castration, and during testosterone treatment, was investigated. RNA synthesis was increased by testosterone treatment, to varying degree, in adult and in prepubertal castrated rats, and was not merely dependent on the degree of hypertrophy of the LAM. The DNA content and the incorporation rate of formate-14C into DNA showed a characteristic profile under the same conditions: the atrophy of LAM following castration and its subsequent restoration appeared to be accompanied by variations in nuclei number. The possible role of testosterone in DNA duplication and in cell mitosis is hypothesized here; further investigation must be integrated by careful morphometric observation. 相似文献
25.
In 300 Sienese skulls of known age and sex (146 male and 154 female) 6 modes of expression of bipartition of the hypoglossal canal were studied on the basis of a new scheme of notation that takes into account gradually increasing intensity. The analysis of data, including also the traditional method of notation confirms the criticisms expressed by various authors on the loss of information when the variability of this trait is neglected, especially with reference to age-dependent changes (hyperostotic effects). 相似文献
26.
Summary Restriction endonucleases have been recently proved to be active on fixed chromosomes, thus they are useful in chromatin structure studies. Within this class of enzymes, Alu I is able to detect the presence and localization of highly repetitive DNA sequences in human and in other mammalian and dipteran species. In this paper the pattern obtained on fixed metaphase chromosomes of orangutan (Pongo pygmaeus) by Alu I digestion and Giemsa staining is shown. The results are discussed in the light of the distribution, in this species, of the I–IV human satellite DNAs. It is also suggested that in Pongo some highly repetitive sequences, different from the major human satellites, are present. 相似文献
27.
Two HL60 clones (C12 and C13) totally insensitive to differentiation induction by dimethylsulfoxide (Me2SO) are described. They have been growing continuously in the presence of the inducer for more than 6 months. The morphological and cytochemical features of the two populations are quite similar to those of the original HL60 cell line, whereas a different karyotype with marked hyperploidy (modal chromosome number of 86 for C12 and 82 for C13) was detected. An antigenic pattern analogous to that of the native HL60 cell line was found in C12 and C13 populations using three monoclonal antibodies differently reactive to myeloid cells. Both clones can be induced to differentiate by retinoic acid (RA) and 12-O-tetradecanoylphorbol 13-acetate (TPA). The pattern of differentiation was assessed by morphological, cytochemical, phenotypical and functional markers. Differentiation of C12 cells by RA and TPA was similar to that observed with native HL60 cells, whereas C13 cells showed lower degrees of sensitivity to RA and TPA. The data presented suggest the existence of different mechanisms for induction of differentiation by Me2SO, RA and TPA. In addition, they are in accordance with previous observations of different degrees of inducibility to differentiation among leukemic cell populations in culture. 相似文献
28.
Chick embryo chorioallantoic membrane, infected with the Blacksburg strain of Newcastle disease virus, was examined with an electron microscope to investigate the sequence of viral-induced host cell alterations. These were evident mostly in the endodermal epithelial cells lining the allantoic sac and were divided arbitrarily into three stages. Stage 1 was characterized by commencement of cell hypertrophy and hyperplasia and presence of fewer cytoplasmic inclusion bodies normally found in the cells; in stage 2, juxtanuclear nucleocapsid-glycogen aggregates appeared, and there were increased numbers of microvilli; stage 3 was characterized by increased cytoplasmic density and evidence of viral assembly and release. The morphological features of viral assembly and the virion are also described. 相似文献
29.
Henry S. Di Stefano 《Cell and tissue research》1966,70(3):322-333
Summary Electron microscope examination of the plasma membrane of chick embryo fibroblasts cultured in vitro revealed the presence of a single osmiophilic layer about 90 Å thick and a substructure composed of ovoid sub-units associated with an amorphous component. These ovoid sub-units measured approximately 112 Å along the major axis and 75 Å along the minor axis and were composed of a central core, approximately 30 Å by 60 Å, surrounded by a peripheral component.Examination of other membranous components of these cells revealed a similar ovoid subunit structure in a single layered membrane. Differences in thickness and in the sizes of ovoid sub-units were seen in these membranes. The ergastoplasmic membranes, the outer nuclear membranes, the outer mitochondrial and the Golgi membranes were found to be the thinnest.These varied in thickness from approximately 75 Å to 80 Å. The thickest membranes seen were the inner nuclear membranes. These were approximately 100 Å thick. The dimensions of the ovoid sub-units corresponded with differences in the thickness of the various membranes. These findings support the concept of a particulate substructure of cell membranes.This work was aided by Research Grant PH 5593 from the National Science Foundation. Some of the equipment used was purchased with funds from the National Institutes of Health Grant 2TI GM 326. I wish to thank Dr. Robert M. Dougherty from the Department of Microbiology who grew and supplied me with the chick embryo fibroblast cultures used in these studies, and Mrs. Ursula Feller fer her technical assistance. 相似文献
30.