Inhibition of cell motility by interferon

Interferon derived from human leukocytes, human fibroblasts, and mouse fibroblasts was found to inhibit the motility of cultured cells. It inhibits the tumor-induced motility of capillary endothelial cells as well as the spontaneous migration of other cell types. The ability of a given preparation of interferon to inhibit the motility of a given cell type is proportional to its antiviral activity in that particular cell type. Antiserum to human leukocyte interferon neutralizes both the motility-inhibitory activity and the antiviral activity of this preparation.     

兔成纤维细胞的分离与体外培养

用Ⅰ型、Ⅳ型胶原酶消化分离兔皮肤细胞,Ⅰ型胶原酶消化皮肤块获得的细胞数显著高于Ⅳ型胶原酶。用组织块直接培养法,也可以得到皮肤的原代培养细胞。２．５ｇ／Ｌ胰酶消化胎儿组织,可获得足够原代培养的细胞量。结合使用酶消化法和反复贴壁法,经２～３代后,可获得纯化的成纤维细胞。分离纯化的胎儿和皮肤成纤维细胞的生长曲线都正常且相似。胎儿和皮肤成纤维细胞可分别传至第１３代与第１１代,传代后染色体数目不变。     

Induction of cellular senescence in immortalized cells by human chromosome 1

The control of cellular senescence by specific human chromosomes was examined in interspecies cell hybrids between diploid human fibroblasts and an immortal, Syrian hamster cell line. Most such hybrids exhibited a limited life span comparable to that of the human fibroblasts, indicating that cellular senescence is dominant in these hybrids. Karyotypic analyses of the hybrid clones that did not senesce revealed that all these clones had lost both copies of human chromosome 1, whereas all other human chromosomes were observed in at least some of the immortal hybrids. The application of selective pressure for retention of human chromosome 1 to the cell hybrids resulted in an increased percentage of hybrids that senesced. Further, the introduction of a single copy of human chromosome 1 to the hamster cells by microcell fusion caused typical signs of cellular senescence. Transfer of chromosome 11 had no effect on the growth of the cells. These findings indicate that human chromosome 1 may participate in the control of cellular senescence and further support a genetic basis for cellular senescence.     

Assignment of the murine interferon sensitivity and cytoplasmic superoxide dismutase genes to chromosome 16

Both hybrids of mouse and human microcells and whole cell hybrids generated by the fusion of primary mouse cells and SV40-transformed human fibroblasts were used to establish the syntenic association of the murine cytoplasmic superoxide dismutase and the interferon sensitivity genes on mouse chromosome 16. This assignment adds two new markers to chromosome 16 and provides another example of an evolutionarily conserved linkage. This finding also provides an animal model both for cellular responsiveness to interferon and for Down's syndrome.     

Interferon binding: the first step in establishment of antiviral activity

Chick cells incubated at 1 degrees C with interferon fail to develop antiviral activity, but this activity appears subsequent to a 7-hour incubation at 37 degrees C after removal of interferon by repeated washings. Treatment with actinomycin D blocks the development of the latter activity. Cells incubated with interferon at 1 degrees C for up to 1 hour and then washed and incubated for 2 hours at 37 degrees C develop a degree of antiviral activity proportional to the concentration of interferon at initial incubation; at any concentration, the antiviral activity increased with the duration of initial incubation at 1 degrees C, but a maximal response was reached at 10 or 20 minutes. Treatment with trypsin after incubation with interferon at 1 degrees C inhibited development of antiviral activity. Interferon is rapidly bound to a superficial cell site, and this binding is necessary for development of antiviral activity in chick cells.     

Location of the c-yes gene on the human chromosome and its expression in various tissues

Analysis of DNA from human embryo fibroblasts showed that ten Eco RI fragments were hybridizable with the Yamaguchi sarcoma virus oncogene (v-yes). Four of the Eco RI fragments were assigned to chromosome 18 and one to chromosome 6. There was evidence for multiple copies of yes-related genes in the human genome; however, only a single RNA species, 4.8 kilobases in length, was related to yes in various cells.     

Susceptibility of human diploid fibroblast strains to transformation by SV40 virus

A quantitative system has been developed for the study of transformation of human diploid fibroblasts in culture by two oncogenic viruses, SV40 and the E46 strain of adeno 7-SV40 "hybrid" virus. Seven of the eleven cell strains derived from human skin biopsies when infected with SV40 (10(9) tissue culture infective doses per milliliter) gave rise to transformed colonies with approximately the same frequency (0.03 percent). Two strains derived from patients with Fanconi's anemia, an autosomal recessive disease associated with a high incidence of chromosome abnormalities and spontaneous neoplasms, gave values more than ten times higher. Two strains from persons heterozygous for this gene were also considerably more susceptible to viral transformation.     

Gene encoding the beta subunit of S100 protein is on chromosome 21: implications for Down syndrome

S100 protein is a calcium-binding protein found predominantly in the vertebrate nervous system. Genomic and complementary DNA probes were used in conjunction with a panel of rodent-human somatic cell hybrids to assign the gene for the beta subunit of S100 protein to the distal half of the long arm of human chromosome 21. This gene was identified as a candidate sequence which, when expressed in the trisomic state, may underlie the neurologic disturbances in Down syndrome.     

Systemic lupus erythematosus: presence in human serum of an unusual acid-labile leukocyte interferon

A previously undescribed species of human leukocyte, or alpha, interferon is present in the serum of many patients with systemic lupus erythematosus. It was shown to be alpha-interferon by neutralization with specific antiserums, affinity column chromatography, and antiviral activity on bovine cells. However, 23 of 30 interferon samples tested were inactivated by incubation at pH 2, a characteristic of human "immune," or gamma, interferon. Multiple samples of interferon from the same patient had similar biological properties, but samples from different patients were not all identical, suggesting that several variants of this species of human alpha-interferon may exist.     

A chromosome 21 critical region does not cause specific Down syndrome phenotypes

The "Down syndrome critical region" (DSCR) is a chromosome 21 segment purported to contain genes responsible for many features of Down syndrome (DS), including craniofacial dysmorphology. We used chromosome engineering to create mice that were trisomic or monosomic for only the mouse chromosome segment orthologous to the DSCR and assessed dysmorphologies of the craniofacial skeleton that show direct parallels with DS in mice with a larger segmental trisomy. The DSCR genes were not sufficient and were largely not necessary to produce the facial phenotype. These results refute specific predictions of the prevailing hypothesis of gene action in DS.     

Serine requirement in leukemic and normal blood cells

In a serine-deficient medium, cells from humangt chronic granulocytic leukemia and normal human bone marrow exhibited a marked inhibition of incorporation of-radioactive precursors of DNA, RNA, and protein into an acid insoluble cell fraction. Normal diploid human fibroblasts did not exhibit inhibition without serine. Chronic granulocytic leukemia and normal marrow cells were essentially unable to synthesize C(14)-serine from C(14)-glucose, while human diploid fibroblasts were highly capable of this synthesis.     

Somatic cell hybrid between the established human line D98 (presumptive HeLa) and 3T3

Somatic cell hybrids have been made between an established human cell line with a long culture history and established mouse fibroblast line. When first analyzed, the hybrid cells contained nearly twice as many mouse chromosomes as the mouse parent line and a human chromosome complemnent of about half that of the human parent. There was further loss of human chromosomes on continued cultivation. This behavior resembles that of other human mouse hybrids and appears to be characteristic of the human-mouse combination. However, the number of human chromosomes is greater than in hybrids made from human diploid fibroblasts. Some clones contain more than a haptoid quantity of human DNA per cell and should synthesize a much greater number of human gene products.     

Recombinant human tumor necrosis factor-alpha: effects on proliferation of normal and transformed cells in vitro

Modulation of the growth of human and murine cell lines in vitro by recombinant human tumor necrosis factor-alpha (rTNF-alpha) and recombinant human interferon-gamma (rIFN-gamma) was investigated. rTNF-alpha had cytostatic or cytolytic effects on only some tumor cell lines. When administered together with rIFN-gamma, rTNF-alpha showed enhanced antiproliferative effects on a subset of the cell lines tested. In contrast to its effects on sensitive tumor cells, rTNF-alpha augmented the growth of normal diploid fibroblasts. Variations in the proliferative response induced by rTNF-alpha were apparently not due to differences in either the number of binding sites per cell or their affinity for rTNF-alpha. These observations indicate that the effects of rTNF-alpha on cell growth are not limited to tumor cells, but rather that this protein may have a broad spectrum of activities in vivo.     

Obtaining and Cytological Identification of a Set of Primary Trisomics in Cabbage

Selection of primary trisomics of the cabbage （Brassica oleracea var.capitata L） forms an important basis for gene chromosome mapping and for other genetic studies. The cabbage self-fertilization line - 9601 was used as material, using the root-tip cell chromosome number and pollen mother cell chromosome number identification and karyotype analysis to select the primary trisomics from the progenies of 3x x 2x in the cabbage. Many aneuploid plants with one or two extra chromosomes were obtained and a set of primary trisomics （Tri-1, Tri-2, Tri-3, Tri-4, Tri-5, Tri-6, Tri-7, Tri-8, and Tri-9, in which the Tri-1 and Tri-4 were from 2n＋2 plants and others from 2n＋ 1 plants） was acquired from these plants. Each trisomic exhibited some unique features, such as plant height, plant type, leaf type, size of flower bud, and inflorescence. The triploid crossing by the diploid is a convenient and effective way to select trisomics in the cabbage.     

Parasexual cycle in cultivated human somatic cells

Somatic segregation for three different autosomes was demonstrated in two strains of human diploid fibroblasts derived from subjects known to be heterozygous for chromosomal variants. Recombinant diploid cells appeared within cultures of tetraploid clones isolted from mass cultures. Tetraploid cells regularly occur in mass cultures and within clones of diploid cells. Such a parasexual cycle (2n-->4n-->2n), with recombination of entire linkage groups, could from the basis of a beginning formal genetic analysis in man.     

低血清培养的BHK21细胞染色体遗传稳定性分析

[目的]对一种商业化的低血清培养基适应BHK21细胞进行传代培养,并分析该细胞染色体的变异稳定性,以判定其质量。[方法]采用直接法制备4个代次BHK21细胞的染色体标本,用常规Giemsa染色,在1 000倍光学显微镜下计数中期分裂相染色体数目,并进行核型分析。[结果]BHK21为亚二倍体或亚四倍体细胞系,亚二倍体总数为42,亚四倍体细胞总数为72~74,该细胞系染色体的畸变率在各代次所占比例为0~2%,均较低。[结论]该细胞系的遗传学特性相对稳定,各代次间无本质差异,可候选为制苗用细胞。     

Induction of collagenolytic and proteolytic activities in rat and human fibroblasts by anti-inflammatory drugs

Confluent monolayers of either mouse or diploid human fibroblasts contained no measurable amounts of either collagenolytic (pH 5.5) or proteolytic (pH 7.5) activities. Within a few hours after exposure of these cells to antiinflammatory drugs, significant amounts of these enzymatic activities were demonstrable extracellularly. These activities were profoundly decreased in cultures simultaneously treated with the anti-inflammatory drugs and cycloheximide or actinomycin D.     

Nonrandomness of translocations in man: preferential entry of chromosomes into 13-15-21 translocations

Lymphocytes from 20 individuals with Down's syndrome due to 13-15/21 centric-fusion translocations were studied by autoradiography after continuous late labeling with tritiated thymidine. In no case was chromosome 13 involved; chromosome 14 was involved in 18 cases, and chromosome 15 in two cases. These results are similar to those from 13 previously studied cases and indicate that the entry of chromosomes 13-15 into translocations is nonrandom. This nonrandomness is not a simple function of chromosome size or shape, since chromosomes 13-15 are acrocentrics of similar size.     

乌苏里江唇（魚骨）(Hemibarbus labeo Pallas)的细胞遗传学分析

采用体内注射PHA和秋水仙素、肾细胞短期培养、常规空气干燥方法,制备乌苏里江唇(魚骨)的染色体。对其肾细胞染色体数目统计分析结果表明,乌苏里江唇(魚骨)的染色体数染色体组有50条染色体,8对中部着丝点染色体(m),8对亚中部着丝点染色体(sm),9对端部着丝点染色体和亚端部着丝点染色体(st,t),其染色体臂数(NF)...     

Immune specific induction of interferon production in cultures of human blood lymphocytes

Human blood lymphocytes stimulated with nonviral antigens in vitro produce an antiviral substance with the biological and biochemical characteristics of interferon. The induced response was specific for cells obtained from immune donors. Cells from nonimmune donors did not produce interferon on exposure to these substances. The quantity of interferon produced by antigen stimulation was related to concentration of antigen over a relatively narrow range; with higher concentrations induction was decreased. Interferon production was maximum during days 4 to 7 in culture. In contrast, phytohemagglutinin-induced interferon was primarily produced during the first 4 days in culture.