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Horoyuki Shimizu Deborah Wyatt Rebecca D. Knowles Corazon D. Bucana Eric J. Stanbridge Eugenie S. Kleinerman 《Cancer immunology, immunotherapy : CII》1989,28(3):185-192
Summary The characteristics of the binding of human monocytes to tumor cells were studied by a newly developed microassay. First, we determined the kinetics and optimal conditions of the binding. Monocytes recognized and bound to tumor cells very rapidly within 10–20 min of cellular interaction. Binding was also more efficient at 37°C suggesting that active metabolism of monocytes is required. Second, we determined that selective binding of monocytes to cells with tumorigenic phenotypes occurs. For this purpose, lymphocytic leukemia cell lines versus normal lymphocytes, and tumorigenic versus nontumorigenic hybrids from the same parental lines were compared as the targets of the binding assay. In both cases, neoplastic cells were selectively bound by monocytes. Although tumor cells were bound rapidly and selectively by monocytes, initial recognition and binding did not necessarily lead to subsequent tumor cell lysis. This is based on the observation that some tumorigenic parental and hybrid lines were avidly bound by monocytes yet not subsequently killed in a cytotoxicity assay.This work was supported in part by a grant from the National Institutes of Health CA42992 and a grant from the Kleberg foundation
Abbreviations used: [125I]IdUrd [125I]iododeoxyuridine; rIFN-, recombinant human interferon ; IL-1, interleukin 1; rTNF, recombinant human tumor necrosis factor 相似文献
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Injection of purified autoantibodies against human centromeric proteins into HeLa cells during interphase disrupts the organization of the kinetochore and interferes with chromosomal movements during the subsequent mitosis even though the chromosomes retain the ability to bind microtubules. We have investigated the hypothesis that this phenotype arises from effects on cytoplasmic dynein, the microtubule motor protein. In previous experiments we found that introduction of anticentromere antibodies into cell nuclei during the G1- or S-phases causes a prometaphase-like arrest, while injections during G2-phase cause a metaphase arrest. We show here that, in both cases, the level of detectable cytoplasmic dynein at kinetochores is significantly decreased. In contrast, when injected cells were permitted to enter mitosis in the absence of microtubules (conditions where trilaminar kinetochores could be detected by electron microscopy), the intensity of dynein labeling on the kinetochores was identical to that seen in uninjected control cells exposed to colcemid. Therefore, the loss of dynein label on mitotic kinetochores was correlated both with the injection of anticentromere antibodies and with the presence of intact spindle microtubules. We suggest that the injection of anticentromere antibodies somehow weakens the association of dynein with the kinetochore, so that when microtubules are present, these motor molecules are pulled away from the kinetochores as they generate force. This model offers an explanation for the failure of chromosomes of injected cells to move normally in mitosis even though they have attached microtubules. 相似文献
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John Curry Rebecca Huss-Ashmore Brian Perry Adrian Mukhebi 《Human ecology: an interdisciplinary journal》1996,24(2):161-189
As livestock disease control programs in Africa begin to rely more upon para-professionals and livestock producers as deliverers of animal health care services, understanding the role different household members play in providing animal health care becomes increasingly important. This paper presents a framework for the analysis of gender aspects of livestock disease control based on a similar framework developed by Feldstein and Poats (1989). The utility of this framework is illustrated using household-level data collected from a district in central Kenya. Adult women and elderly men in the sample have primary responsibility for livestock care, and are therefore well placed to diagnose illness. Dipping and spraying of animals to prevent tick-borne and other diseases is the primary responsibility of adult males. Decisions regarding use of milk from the morning milking are more likely to be made by adult men. It is morning milk that is most often sold. Adult women, however, make decisions about use of evening milk, which is most often kept for household consumption. Knowledge of livestock diseases did not appear to vary significantly by gender, although some elderly men did possess extensive knowledge of indigenous disease categories and traditional remedies. The importance of recognizing gender issues in planning and implementing livestock disease control programs is discussed. 相似文献
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Both nitric oxide and prostaglandins are potent paracrine mediators of intercellular communication. An endotoxin-lipopolysaccharide (LPS) inducible form of nitric oxide synthase (mac-NOS) has recently been cloned from murine macrophages. An inducible prostaglandin synthase (TIS1O/PGS-2), cloned from 3T3 cells, is also induced in LPS-activated macrophage. Because of the wide range of ligands that induce primary response genes in 3T3 cells, the ease of studying chimeric promoter constructs in 3T3 cells, and the importance of both nitric oxide and prostaglandins as paracrine mediators, we examined expression of mac-NOS in 3T3 cells. Tetradecanoyl phorbol-13 acetate (TPA), forskolin, platelet-derived growth factor, fibroblast growth factor, and serum all induce mac-NOS expression in Swiss 3T3 cells. Thus the mac-NOS gene can respond to a far wider range of inducers than previously suspected. mac-NOS is a primary response gene; cycloheximide does not block induction. TPA-induced mac-NOS and TIS10/PGS-2 mRNA accumulation patterns are similar. LPS is a potent inducer of mac-NOS in Swiss 3T3 cells but cannot induce TIS10/PGS-2. In contrast, v-src expression induces TIS10/PGS-2 message, but not iNOS message in a BALB/c 3T3 cell line containing a temperature-sensitive v-src gene. Dexamethasone (DEX) prevents induction of TIS10/PGS-2, but not most other primary response genes. DEX also blocks mac-NOS induction in Swiss 3T3 cells. The inducible TIS10/PGS-2 and mac-NOS genes, responsible for the production of two distinct paracrine agents, appear to share many regulatory features in 3T3 cells. © 1993 Wiley-Liss, Inc. 相似文献
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Georgina W. Hall Maurizio Sampietro Rebecca Barnetson Joan Fitzgerald Shaun McCann SweeLay Thein 《Human genetics》1993,92(1):28-32
Using the technique of allele-specific priming of the polymerase chain reaction (PCR), the C-T substitution in codon 39 was identified as the cause of -thalassaemia in an Irish family. Analysis of the restriction fragment length polymorphisms (RFLPs) in the -globin gene cluster established linkage of the -thalassaemia mutation to a particular -haplotype but indicated that a recombinational event had occurred in the paternal chromosome in the younger of two affected children. Non-paternity was excluded by DNA fingerprinting analysis with hypervariable minisatellite probes. This is the fourth case of recombination in the -globin gene cluster to be reported. The event has occurred 5 of the polymorphic RsaI site at position-550 bp upstream of the -globin gene mRNA Cap site, within the 9.1-kb region that has been shown to be a hot spot for recombination in the -globin gene cluster. 相似文献
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Vito W. Rebecca Jessie Villanueva Marie R. Webster 《Pigment cell & melanoma research》2023,36(6):576-582
To commemorate the 20th Anniversary of the Society of Melanoma Research and the first International Melanoma Research Congress held in June of 2003, we have described in brief, how the Society for Melanoma Research (SMR) began, the purpose, goals, and governance of the SMR, and how the society has evolved to support new melanoma researchers. In celebration of the immense progress in treating melanoma patients over the last 20 years and the impact of the SMR on these advances, we have highlighted memories and insight from early SMR members and founders. 相似文献