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941.
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Circulating Tumor Cells(CTC)have the potential to be used clinically as a diagnostic tool and a treatment tool in the fieldof oncology.As a diagnostic tool,CTC may be used to indicate the presence of a tumor before it is large enough to cause noticeablesymptoms.As a treatment tool,CTC isolated from patients may be used to test the efficacy of chemotherapy options topersonalize patient treatment.One way for tumors to spread is through metastasis via the circulatory system.CTC are able toexploit the natural leukocyte recruitment process that is initially mediated by rolling on transient selectin bonds.Our capturedevices take advantage of this naturally occurring recruitment step to isolate CTC from whole blood by flowing samples throughselectin and antibody-coated microtubes.Whole blood was spiked with a known concentration of labeled cancer cells and thenperfused through pre-coated microtubes.Microtubes were then rinsed to remove unbound cells and the number of labeled cellscaptured on the lumen was assessed.CTC were successfully captured from whole blood at a clinically relevant level on the orderof 10 cells per mL.Combination tubes with selectin and antibody coated surface exhibited higher capture rate than tubes coatedwith selectin alone or antibody alone.Additionally,CTC capture was demonstrated with the KG 1 a hematopoietic cell line andthe DU 145 epithelial cell line.Thus,the in vivo process of selectin-mediated CTC recruitment to distant vessel walls can be usedin vitro to target CTC to a tube lumen.The biomolecular coatings can also be used to capture CTC of hematopoietic andepithelial tumor origin and is demonstrated to sensitivities down to the order of 10 CTC per mL.In a related study aimed at reducing the blood borne metastatic cancer load,we have shown that cells captured to a surfacecan be neutralized by a receptor-mediated biochemical signal.In the proposed method we have shown that using a combinedselectin and TRAIL(TNF Related Apoptosis Inducing Ligand or Apo 2L)functionalized surface we are abl 相似文献
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Kirstie M. Bertram Naomi R. Truong Jacinta B. Smith Min Kim Kerrie J. Sandgren Konrad L. Feng Jason J. Herbert Hafsa Rana Kevin Danastas Monica Miranda-Saksena Jake W. Rhodes Ellis Patrick Ralph C. Cohen Jake Lim Steven L. Merten Andrew N. Harman Anthony L. Cunningham 《PLoS pathogens》2021,17(4)
Skin mononuclear phagocytes (MNPs) provide the first interactions of invading viruses with the immune system. In addition to Langerhans cells (LCs), we recently described a second epidermal MNP population, Epi-cDC2s, in human anogenital epidermis that is closely related to dermal conventional dendritic cells type 2 (cDC2) and can be preferentially infected by HIV. Here we show that in epidermal explants topically infected with herpes simplex virus (HSV-1), both LCs and Epi-cDC2s interact with HSV-1 particles and infected keratinocytes. Isolated Epi-cDC2s support higher levels of infection than LCs in vitro, inhibited by acyclovir, but both MNP subtypes express similar levels of the HSV entry receptors nectin-1 and HVEM, and show similar levels of initial uptake. Using inhibitors of endosomal acidification, actin and cholesterol, we found that HSV-1 utilises different entry pathways in each cell type. HSV-1 predominantly infects LCs, and monocyte-derived MNPs, via a pH-dependent pathway. In contrast, Epi-cDC2s are mainly infected via a pH-independent pathway which may contribute to the enhanced infection of Epi-cDC2s. Both cells underwent apoptosis suggesting that Epi-cDC2s may follow the same dermal migration and uptake by dermal MNPs that we have previously shown for LCs. Thus, we hypothesize that the uptake of HSV and infection of Epi-cDC2s will stimulate immune responses via a different pathway to LCs, which in future may help guide HSV vaccine development and adjuvant targeting. 相似文献
947.
Virus-free and artichoke latent virus (ALV) infected plants of ‘Brindisino’ artichoke obtained by in vitro propagation, were studied over a period of three years to evaluate the effect of ALV infection on artichoke field performance and to determine the infection rate of healthy plants. ALV infection caused qualitative and quantitative changes ‘Brindisino’ artichoke such as leaf and bract discoloration, opening of head apex, delay of first harvest, shortening of head stalk, reduction of head width and a dramatic decrease of yield. Due to the high infection rate of healthy plants during the trial period, the differences in the production of heads between the two groups of plants decreased in the last year of experiment. 相似文献
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Covalent and non-covalent conjugation of proteins to nanoparticles provides access to functional hybrid systems with applications in biotechnology, medicine, and catalysis. The creation of effective conjugates requires the retention of protein structure and function, a challenging task. In this review we discuss successes, challenges and opportunities in the area of protein-nanoparticle bioconjugation. 相似文献
950.
Qi Guo Jasmin K. Sidhu Timothy M. D. Ebbels Faisal Rana David J. Spurgeon Claus Svendsen Stephen R. Stürzenbaum Peter Kille A. John Morgan Jacob G. Bundy 《Metabolomics : Official journal of the Metabolomic Society》2009,5(1):72-83
One of the promises of environmental metabolomics, together with other ecotoxicogenomic approaches, is that it can give information
on toxic compound mechanism of action (MOA), by providing a specific response profile or fingerprint. This could then be used
either for screening in the context of chemical risk assessment, or potentially in contaminated site assessment for determining
what compound classes were causing a toxic effect. However for either of these two ends to be achievable, it is first necessary
to know if different compounds do indeed elicit specific and distinct metabolic profile responses. Such a comparative study
has not yet been carried out for the earthworm Lumbricus rubellus. We exposed L. rubellus to sub-lethal concentrations of three very different toxicants (CdCl2, atrazine, and fluoranthene, representing three compound classes with different expected MOA), by semi-chronic exposures
in a laboratory test, and used NMR spectroscopy to obtain metabolic profiles. We were able to use simple multivariate pattern-recognition
analyses to distinguish different compounds to some degree. In addition, following the ranking of individual spectral bins
according to their mutual information with compound concentrations, it was possible to identify both general and specific
metabolite responses to different toxic compounds, and to relate these to concentration levels causing reproductive effects
in the worms.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Qi Guo and Jasmin K. Sidhu contributed equally to this paper. 相似文献