Real-Time Investigation of Engineered Nanomaterials Cytotoxicity in Living Alveolar Epithelia with Hopping Probe Ion Conductance Microscopy

Widely used engineered nanomaterials (NMs) display unique properties that may have impact on human health, and thus require a reliable evaluation of their potential cytotoxicity. There is a continuing need for real-time imaging techniques capable of studying the interactions between NMs and living alveolar epithelial cells under physiological conditions. A new developed noninvasive HPICM is designed for continuous high-resolution topographic imaging of living cells, which makes it an ideal tool to study NMs cytotoxicity in living alveolar epithelia by performing reliable repetitive scanning. In this review, we concisely introduced the operation principle of HPICM and its applications to real-time investigation of engineered NMs cytotoxicity in living alveolar epithelia. Published results demonstrate that non-contact HPICM combined with patch-clamp has the potential to become a powerful microscopy for real-time studies of NM-cell interactions under physiological conditions.

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Molecular Beacons: Powerful Tools for Imaging RNA in Living Cells

Journal of Nucleic Acids ◽

10.4061/2011/741723 ◽

2011 ◽

Vol 2011 ◽

pp. 1-15 ◽

Cited By ~ 35

Author(s):

Ricardo Monroy-Contreras ◽

Luis Vaca

Keyword(s):

Real Time ◽

Imaging Techniques ◽

Spatial Separation ◽

Living Cells ◽

Molecular Beacons ◽

Cell Physiology ◽

Complementary Sequence ◽

Stem Loop ◽

Recent Advances

Recent advances in RNA functional studies highlights the pivotal role of these molecules in cell physiology. Diverse methods have been implemented to measure the expression levels of various RNA species, using either purified RNA or fixed cells. Despite the fact that fixed cells offer the possibility to observe the spatial distribution of RNA, assays with capability to real-time monitoring RNA transport into living cells are needed to further understand the role of RNA dynamics in cellular functions. Molecular beacons (MBs) are stem-loop hairpin-structured oligonucleotides equipped with a fluorescence quencher at one end and a fluorescent dye (also called reporter or fluorophore) at the opposite end. This structure permits that MB in the absence of their target complementary sequence do not fluoresce. Upon binding to targets, MBs emit fluorescence, due to the spatial separation of the quencher and the reporter. Molecular beacons are promising probes for the development of RNA imaging techniques; nevertheless much work remains to be done in order to obtain a robust technology for imaging various RNA molecules together in real time and in living cells. The present work concentrates on the different requirements needed to use successfully MB for cellular studies, summarizing recent advances in this area.

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Genetically encoded tags for real time dissection of protein assembly in living cells

Chemical Science ◽

10.1039/c8sc00839f ◽

2018 ◽

Vol 9 (25) ◽

pp. 5551-5555 ◽

Cited By ~ 1

Author(s):

Guolin Ma ◽

Qian Zhang ◽

Lian He ◽

Nhung T. Nguyen ◽

Shuzhong Liu ◽

...

Keyword(s):

Protein Structure ◽

Real Time ◽

Protein Assembly ◽

Living Cells ◽

Protein Target ◽

Physiological Conditions

Genetically encoded tags (MoTags) to assess protein oligomeric states, probe protein structure and monitor protein–target interactions under physiological conditions in cellulo.

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Ultrastructural immunoperoxidase demonstration of autologous albumin in the alveolar capillary membrane and in the alveolar lining material in normal rats.

The Journal of Cell Biology ◽

10.1083/jcb.64.2.503 ◽

1975 ◽

Vol 64 (2) ◽

pp. 503-509 ◽

Cited By ~ 35

Author(s):

J Bignon ◽

P Chahinian ◽

G Feldmann ◽

C Sapin

Keyword(s):

Cell Types ◽

Alveolar Epithelial Cells ◽

Autologous Serum ◽

Type I ◽

Physiological Conditions ◽

Alveolar Epithelial ◽

Capillary Membrane ◽

Lining Material ◽

Alveolar Capillary ◽

Pinocytic Vesicles

The location of autologous serum albumin within the alveolar-capillary membrane was studied in the rat under physiological conditions using antialbumin antibodies labeled with peroxidase. Albumin was detected in the lung interstitium, and in numerous pinocytic vesicles within endothelial cells and type I alveolar epithelial cells. The immunoreaction was also positive at the level of plasmalemmal membranes of both cell types and in the alveolar lining material.

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Assessment of Mechanical Properties of Adherent Living Cells by Bead Micromanipulation: Comparison of Magnetic Twisting Cytometry vs Optical Tweezers

Journal of Biomechanical Engineering ◽

10.1115/1.1485285 ◽

2002 ◽

Vol 124 (4) ◽

pp. 408-421 ◽

Cited By ~ 110

Author(s):

Vale´rie M. Laurent ◽

Sylvie He´non ◽

Emmanuelle Planus ◽

Redouane Fodil ◽

Martial Balland ◽

...

Keyword(s):

Mechanical Properties ◽

Optical Tweezers ◽

Viscoelastic Properties ◽

Young Modulus ◽

Living Cells ◽

Alveolar Epithelial Cells ◽

Time Constants ◽

Alveolar Epithelial ◽

Magnetic Twisting Cytometry ◽

Relaxation Time Constants

We compare the measurements of viscoelastic properties of adherent alveolar epithelial cells by two micromanipulation techniques: (i) magnetic twisting cytometry and (ii) optical tweezers, using microbeads of same size and similarly attached to F-actin. The values of equivalent Young modulus E, derived from linear viscoelasticity theory, become consistent when the degree of bead immersion in the cell is taken into account. E-values are smaller in (i) than in (ii): ∼34–58 Pa vs ∼29–258 Pa, probably because higher stress in (i) reinforces nonlinearity and cellular plasticity. Otherwise, similar relaxation time constants, around 2 s, suggest similar dissipative mechanisms.

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