In vivo dynamic light scattering microscopy of tumour blood vessels

In vivo screening of phage-displayed peptide libraries has revealed extensive molecular differences in the blood vessels of individual normal tissues. Pathological lesions also put their signature on the vasculature; in tumours, both blood and lymphatic vessels differ from normal vessels. The changes that characterize tumour blood vessels include selective expression of certain integrins. Peptides isolated by in vivo phage display for homing to tumours have been shown to be useful in directing therapeutic agents to experimental tumours. The targeting can enhance the efficacy of the therapy while reducing side effects. Phage screening has also revealed lung-specific vascular markers that promote tumour metastasis to the lungs by mediating specific adherence of tumour cells to the lung vasculature. These phage-screening studies have revealed a previously unsuspected degree of vascular specialization and provide potentially useful guidance devices for targeted therapies.

Download Full-text

Protein size resolution in human eye lenses by dynamic light scattering after in vivo measurements

Graefe s Archive for Clinical and Experimental Ophthalmology ◽

10.1007/s004170050037 ◽

1998 ◽

Vol 236 (1) ◽

pp. 18-23 ◽

Cited By ~ 4

Author(s):

Karsten Dierks ◽

Matthias Dieckmann ◽

Dirk Niederstrasser ◽

Robert Schwartz ◽

Alfred Wegener

Keyword(s):

Light Scattering ◽

Dynamic Light Scattering ◽

Human Eye ◽

In Vivo Measurements ◽

Protein Size

Download Full-text

MACROMOLECULAR CROWDING IN BIOLOGICAL SYSTEMS: DYNAMIC LIGHT SCATTERING (DLS) TO QUANTIFY THE EXCLUDED VOLUME EFFECT (EVE)

Biophysical Reviews and Letters ◽

10.1142/s1793048006000215 ◽

2006 ◽

Vol 01 (03) ◽

pp. 317-325 ◽

Cited By ~ 21

Author(s):

KARTHIK S. HARVE ◽

MICHAEL RAGHUNATH ◽

RICKY R. LAREU ◽

RAJ RAJAGOPALAN

Keyword(s):

Light Scattering ◽

Dynamic Light Scattering ◽

Biological Systems ◽

Volume Effect ◽

Threshold Concentration ◽

Excluded Volume ◽

Matrix Deposition ◽

Excluded Volume Effect

Macromolecules crowd defined spaces, thereby excluding other like-sized molecules from the volume they occupy. These excluded-volume effect(s) (EVE) are well characterized for intracellular and partially for extracellular compartments such as blood plasma. We showed that EVE in fibroblast culture leads to faster enzymatic procollagen conversion and matrix deposition. Apparently, EVE can be applied to emulate in vivo conditions in an in vitro setting. Thus, we attempted to quantitatively capture the crowding potential of various macromolecules using dynamic light scattering under physiological conditions. We found that charged macromolecules like dextran sulfate (negative, 500 kDa) have a hydrodynamic radii of 46.4 ± 0.3 nm i.e. ~4 fold larger than that of neutral macromolecules like Ficoll (neutral, 400 kDa) and thus show greater EVE potential. At biologically effective concentrations viscosity was not increased. Unexpectedly, we observed a dramatic drop of hydrodynamic radii of all macromolecules tested above a threshold concentration. This suggested a hyper-crowding state in which the crowders compacted themselves mutually. We will use this hyper-crowding threshold to determine retrogradely rules that allow to predict the conditions for optimum crowding effects (such as the half-hyper-crowding concentration) in biological systems. We propose Dynamic Light Scattering (DLS) as a potential tool to estimate EVE in biotechnical applications.

Download Full-text

Aggregation of Lens Crystallins in an In Vivo Hyperbaric Oxygen Guinea Pig Model of Nuclear Cataract: Dynamic Light-Scattering and HPLC Analysis

Investigative Opthalmology & Visual Science ◽

10.1167/iovs.05-0843 ◽

2005 ◽

Vol 46 (12) ◽

pp. 4641 ◽

Cited By ~ 47

Author(s):

M. Francis Simpanya ◽

Rafat R. Ansari ◽

Kwang I. Suh ◽

Victor R. Leverenz ◽

Frank J. Giblin

Keyword(s):

Light Scattering ◽

Dynamic Light Scattering ◽

Guinea Pig ◽

Hyperbaric Oxygen ◽

Hplc Analysis ◽

Pig Model ◽

Nuclear Cataract ◽

Lens Crystallins ◽

Guinea Pig Model

Download Full-text

Decorrelation Time Analysis Using Dynamic Light Scattering with Optical Coherence Tomography in an in vivo Mouse Tumour Model

10.32920/ryerson.14648115.v1 ◽

2021 ◽

Author(s):

Timothy Wan Hei Luk

Keyword(s):

Optical Coherence Tomography ◽

Light Scattering ◽

Dynamic Light Scattering ◽

Near Infrared ◽

Imaging Modality ◽

Preclinical Study ◽

Infrared Light ◽

Target Tissue ◽

Optical Coherence

Optical coherence tomography (OCT) is an imaging modality that uses near infrared light interferometry for non-invasive, near-histological resolution imaging at the micron level. Concepts from dynamic light scattering (DLS) can be adapted to OCT to detect and measure the motions in the target tissue. Tissue dynamics can be observed by measuring the speckle decorrelation time (DT) of the tissue. DT analysis was performed in a preclinical study to demonstrate the repeatability and feasibility of using DLS-OCT to observe mouse tumours undergoing cisplatin treatment over a 48-hour period. Differences in the average DT data were observed for control and cisplatin-injected mice. Image segmentation based on DT values was also performed to subtract the DT contributions of pixels at blood vessel locations, resulting in the improvement of average DT calculations of the tumour tissue. The results presented are a preliminary step to analyzing and monitoring tumour growth and treatment response in vivo.

Download Full-text

Self -Assembled Raccoon Dog Parvovirus VP2 Protein Confers Immunity Against RDPV Disease in Raccoon Dogs: In Vitro and in Vivo Studies

10.21203/rs.3.rs-161900/v1 ◽

2021 ◽

Author(s):

Linya Xia ◽

Guoliang Luo ◽

Mingjie Wu ◽

Lei Wang ◽

Ning Zhang ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Light Scattering ◽

Dynamic Light Scattering ◽

Raccoon Dog ◽

Vp2 Protein ◽

Transmission Electron ◽

Self Assembled ◽

Raccoon Dogs

Abstract Background: Raccoon dog parvovirus (RDPV) causes acute infectious diseases in raccoon dogs and may cause death in severe cases. Current treatment strategy relies on the extensive usage of classical inactivated vaccine which is marred by large doses, short immunization cycles and safety concerns.Methods: The present study aimed at optimization of RDPV VP2 gene, subcloning the gene into plasmid pET30a, and its subsequent transfer to E. coli with trigger factor 16 for co-expression. The protein thus expressed was purified with ammonium sulfate precipitation, hydrophobic chromatography, and endotoxin extraction procedures. VLPs were examined by transmission electron microscopy, dynamic light scattering, and the efficacy of VLPs vaccine was tested in vivo.Results: Results indicated that RDPV VP2 protein could be expressed soluble. Transmission electron microscopy and dynamic light scattering results indicated that RDPV VP2 self-assembled into VLPs. Hemagglutination inhibition antibody titers elicited by Al(OH)3 adjuvanted RDPV VLPs were comparable with RDPV inactivated vaccines, and the viral loads in the blood of the struck raccoon dogs were greatly reduced. Hematoxylin and eosin and Immunohistochemical results indicated that RDPV VLPs vaccine could protect raccoon dogs against RDPV infections. Conclusions: These results suggest that RDPV VLPs have the ability to become a potential vaccine candidate for RDPV therapy.

Download Full-text