scholarly journals Rapid fabrication of functionalised poly(dimethylsiloxane) microwells for cell aggregate formation

2017 ◽  
Vol 5 (4) ◽  
pp. 828-836 ◽  
Author(s):  
A. Forget ◽  
A. L. S. Burzava ◽  
B. Delalat ◽  
K. Vasilev ◽  
F. J. Harding ◽  
...  
Keyword(s):  
Cell Aggregates ◽  
Cell Aggregate ◽  
Aggregate Formation ◽  
Rapid Fabrication ◽  
Natural Architecture

Cell aggregates reproduce many features of the natural architecture of functional tissues, and have therefore become an important in vitro model of tissue function.

scholarly journals Correction: Rapid fabrication of functionalised poly(dimethylsiloxane) microwells for cell aggregate formation

2017 ◽  
Vol 5 (5) ◽  
pp. 1061-1061
Author(s):  
A. Forget ◽  
A. L. S. Burzava ◽  
B. Delalat ◽  
K. Vasilev ◽  
F. J. Harding ◽  
...  
Keyword(s):  
Cell Aggregate ◽  
Aggregate Formation ◽  
Rapid Fabrication

Correction for ‘Rapid fabrication of functionalised poly(dimethylsiloxane) microwells for cell aggregate formation’ by A. Forget et al., Biomater. Sci., 2017, 5, 828–836.

scholarly journals Increased Platelet-CD4+ T Cell Aggregates Are Correlated With HIV-1 Permissiveness and CD4+ T Cell Loss

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiao-Peng Dai ◽  
Feng-Ying Wu ◽  
Cheng Cui ◽  
Xue-Jiao Liao ◽  
Yan-Mei Jiao ◽  
...  
Keyword(s):  
T Cell ◽  
Antiretroviral Therapy ◽  
Critical Role ◽  
Cell Loss ◽  
Cd4 T Cell ◽  
Cell Aggregates ◽  
Cell Aggregate ◽  
Aggregate Formation ◽  
Cell Counts ◽  
Hiv 1

Chronic HIV-1 infection is associated with persistent inflammation, which contributes to disease progression. Platelet-T cell aggregates play a critical role in maintaining inflammation. However, the phenotypic characteristics and clinical significance of platelet-CD4+ T cell aggregates remain unclear in different HIV-infected populations. In this study, we quantified and characterized platelet-CD4+ T cell aggregates in the peripheral blood of treatment-naïve HIV-1-infected individuals (TNs), immunological responders to antiretroviral therapy (IRs), immunological non-responders to antiretroviral therapy (INRs), and healthy controls (HCs). Flow cytometry analysis and immunofluorescence microscopy showed increased platelet-CD4+ T cell aggregate formation in TNs compared to HCs during HIV-1 infection. However, the frequencies of platelet-CD4+ T cell aggregates decreased in IRs compared to TNs, but not in INRs, which have shown severe immunological dysfunction. Platelet-CD4+ T cell aggregate frequencies were positively correlated with HIV-1 viral load but negatively correlated with CD4+ T cell counts and CD4/CD8 ratios. Furthermore, we observed a higher expression of CD45RO, HIV co-receptors, HIV activation/exhaustion markers in platelet-CD4+ T cell aggregates, which was associated with HIV-1 permissiveness. High levels of caspase-1 and caspase-3, and low levels of Bcl-2 in platelet-CD4+ T cell aggregates imply the potential role in CD4+ T cell loss during HIV-1 infection. Furthermore, platelet-CD4+ T cell aggregates contained more HIV-1 gag viral protein and HIV-1 DNA than their platelet-free CD4+ T cell counterparts. The platelet-CD4+ T cell aggregate levels were positively correlated with plasma sCD163 and sCD14 levels. Our findings demonstrate that platelet-CD4+ T cell aggregate formation has typical characteristics of HIV-1 permissiveness and is related to immune activation during HIV-1 infection.

Formation of Cell Aggregates Using Microfabricated Hydrogel Chambers for Assembly into Larger Tissues

2013 ◽  
Vol 25 (4) ◽  
pp. 682-689 ◽  
Author(s):  
Masaki Iwase ◽  
◽  
Masumi Yamada ◽  
Emi Yamada ◽  
Minoru Seki
Keyword(s):  
Surface Characteristics ◽  
Fabrication Process ◽  
Cell Aggregates ◽  
Cell Aggregate ◽  
Aggregate Formation ◽  
Cell Type ◽  
Adhesive Surface ◽  
Hydrogel Matrix ◽  
Nih 3T3 ◽  
Tissue Models

This paper presents a fabrication process for cell aggregates with controlled shapes that can be used as building units for constructing relatively large tissue models. Microfabricated hydrogel-based chambers with non-adhesive surface characteristics were prepared via a micromolding process. Alginate was used as the hydrogel matrix, which facilitated the efficient formation of aggregates from cells retained inside the microchamber. We employed several types of toroidal and lattice-shaped hydrogel microchambers with different geometries. We examined the effect of cell type on the aggregate formation process using NIH-3T3, C2C12, and HepG2 cells and clearly observed that aggregation behavior is highly dependent on cell type. In addition, we tried to construct 2-layered capillarylike tissues by stacking heterotypic toroidal cell aggregates, which mimic blood vessels. The presented cell aggregate-based tissue fabrication process could become a versatile approach for preparing complex and scaffold-free 3D tissue models.

scholarly journals Peningkatan Produksi Katarantin Melalui Teknik Elisitasi Pada Kultur Agregat Sel Catharanthus roseus

2011 ◽  
Vol 15 (1) ◽  
pp. 140
Author(s):  
Dingse Pandiangan
Keyword(s):  
High Pressure ◽  
Liquid Chromatography ◽  
Catharanthus Roseus ◽  
Growth Pattern ◽  
The Other ◽  
Cell Aggregates ◽  
Cell Aggregate ◽  
Qualitative And Quantitative ◽  
Treatment Step

ABSTRAK Penelitian ini bertujuan untuk optimasi dan peningkatan produksi antikanker katarantin khususnya elisitasi. Tujuan praktisnya adalah untuk mengetahui pertumbuhan kalus agregat sel C. roseus yang diberi elisitor, menemukan kurva tumbuh S. cerevisiae dan bahan elisitor, menemukan kandungan katarantin pada agregat sel dan medium  perlakuan dan menemukan waktu panen perlakuan elisitasi yang menghasilkan  kandungan katarantin yang paling tinggi. Dari hasil penelitian ini diharapkan dapat dihasilkan suatu informasi mengenai peningkatan katarantin yang dihasilkan (diproduksi) secara kultur (in vitro) untuk dimanfaatkan pada penelitian selanjutnya. Tahapan penelitian dilakukan antara lain 1) tahap kultur S. cerevisiae dan persiapan elisitor, 2) tahap kultur agregat sel dengan perlakuan elisitasi, 3). tahap ekstraksi dan isolasinya menggunakan metanol dan diklorometan 4). tahap uji kuantitas dan kualitas katarantin dengan menggunakan metode Kromatografi Cair Kinerja Tinggi (KCKT) yang dihubungkan dengan kromatopak CR-7A Plus. Kurva tumbuh ragi menunjukkan bahwa fase pertumbuhan maksimum terjadi setelah 16 jam inkubasi. Kandungan katarantin sudah terdeteksi pada hari ke-3 dan mengalami penurunan pada hari ke-6 dan ke-9. Pada hari ke-12, kandungan katarantin mencapai jumlah tertinggi di agregat sel dan mengalami penurunan sampai hari ke-24, Kandungan katarantin tertinggi pada medium terjadi pada hari ke- 18 dan selanjutnya mengalami penurunan sampai hari ke-24. Hasil elisitasi menunjukkan adanya peningkatan kandungan katarantin pada semua waktu panen yang dilakukan, baik dalam sel maupun dalam medium. Kandungan katarantin tertinggi setelah elisitasi pada agregat sel adalah sebesar 274,03 µg/g BK dengan persentase peningkatan sebesar 218,86 % pada jam ke-18. Namun dalam medium adalah pada jam ke-72 sebesar 856,75 µg/L dengan persentae peningkatan sebesar 266,13 %. Kata kunci: katarantin, teknik elisitasi     THE ENHANCEMENT OF CATHARANTHINE PRODUCTION BY ELICITATION  TECHNIC ON Catharanthus roseus CELL AGGREGATES ABSTRACT This research aims were to find out the growth respons and catharanhine content  of C. roseus callus elisitor treatment.  Catharanthine content can be produced on each callus after the elisitor treatment, cell aggregates growth pattern, medium that produces the higher catharanthine content. This research is expected to give some information about the increasing of catharanthine content produced through in vitro process which can be used in further research. The steps have been done in this research, They were 1) Callus culture with elisitor treatment step, 2) cell aggregates culture with elisitor treatment step, 3) extraction and isolation step, 4). The step of qualitative and quantitative assay of catharanthine by using HPLC (High Pressure Liquid Chromatography) connected to cromathopac CR-7A Plus. The result of research showed that the growth curva of S. cerevisiae showed that the highest growth occurred after 16 hours incubation. The highest catharanthine content of the cell aggregate occurred at the 12th day  and then decreased up to 24th day. The result of elisitation indicated, the increasing of catharanthine contents at the all collected days has been done, include in cell and medium. The higest catharanthine content after elicitation of cell aggregate was 274,03 µg/g DW with the presentation of increasing about 218,86 % at the 18th hour. On the other hand, medium was 856,75 µg/L with the presentation of increasing about 266,13 % at the 72th hour. Keywords: catharanthine, elicitation technic

A Simple and Rapid Method to Determine GPIIb/IIIa-Receptor Inhibitor Activity in Whole Blood

1999 ◽  
Vol 19 (03) ◽  
pp. 134-138
Author(s):  
Gitta Kühnel ◽  
A. C. Matzdorff
Keyword(s):  
Flow Cytometry ◽  
Platelet Count ◽  
Blood Sample ◽  
Platelet Activation ◽  
Whole Blood ◽  
Receptor Occupancy ◽  
Aggregate Formation ◽  
Inhibitor Activity ◽  
Receptor Inhibitor

SummaryWe studied the effect of GPIIb/IIIa-inhibitors on platelet activation with flow cytometry in vitro. Citrated whole blood was incubated with increasing concentrations of three different GPIIb/IIIa-inhibitors (c7E3, DMP728, XJ757), then thrombin or ADP were added and after 1 min the sample was fixed. Samples without c7E3 but with 0.1 U/ml thrombin had a decrease in platelet count. Samples with increasing concentrations of c7E3 had a lesser or no decrease in platelet count. The two other inhibitors (DMP 725, XJ757) gave similar results. GPIIb/IIIa-inhibitors prevent aggregate formation and more single platelets remain in the blood sample. The agonist-induced decrease in platelet count correlates closely with the concentration of the GPIIb/IIIa inhibitor and receptor occupancy. This correlation may be used as a simple measure for inhibitor activity in whole blood.

In Vitro Elucidation of the Folding Intermediates and Aggregate Formation of Hemoglobin Induced by Acetonitrile: A Multispectroscopic Approach

2016 ◽  
Vol 23 (10) ◽  
pp. 884-891 ◽  
Author(s):  
Mohammad Furkan ◽  
Asim Rizvi ◽  
Mohammad Afsar ◽  
Mohammad Rehan Ajmal ◽  
Rizwan H. Khan ◽  
...  
Keyword(s):  
Aggregate Formation ◽  
Folding Intermediates

Fibronectin regulates anoikis resistance via cell aggregate formation

2021 ◽  
Author(s):  
Hyeong-jun Han ◽  
Jee Young Sung ◽  
Su-Hyeon Kim ◽  
Un-Jung Yun ◽  
Hyeryeong Kim ◽  
...  
Keyword(s):  
Cell Aggregate ◽  
Aggregate Formation ◽  
Anoikis Resistance

scholarly journals Epithelial Cell Chirality Revealed by Three-Dimensional Spontaneous Rotation

2018 ◽  
Vol 115 (48) ◽  
pp. 12188-12193 ◽  
Author(s):  
Amanda S. Chin ◽  
Kathryn E. Worley ◽  
Poulomi Ray ◽  
Gurleen Kaur ◽  
Jie Fan ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Cell Polarity ◽  
Three Dimensional ◽  
Intrinsic Property ◽  
Cell Aggregates ◽  
Mechanistic Studies ◽  
Directional Bias ◽  
Self Organized ◽  
Dependent Cell

Our understanding of the left–right (LR) asymmetry of embryonic development, in particular the contribution of intrinsic handedness of the cell or cell chirality, is limited due to the confounding systematic and environmental factors during morphogenesis and a ack of physiologically relevant in vitro 3D platforms. Here we report an efficient two-layered biomaterial platform for determining the chirality of individual cells, cell aggregates, and self-organized hollow epithelial spheroids. This bioengineered niche provides a uniform defined axis allowing for cells to rotate spontaneously with a directional bias toward either clockwise or counterclockwise directions. Mechanistic studies reveal an actin-dependent, cell-intrinsic property of 3D chirality that can be mediated by actin cross-linking via α-actinin-1. Our findings suggest that the gradient of extracellular matrix is an important biophysicochemical cue influencing cell polarity and chirality. Engineered biomaterial systems can serve as an effective platform for studying developmental asymmetry and screening for environmental factors causing birth defects.

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