Quantitative characterization of developing collagen gels using optical coherence tomography.

Nondestructive optical imaging methods such as optical coherence tomography (OCT) have been proposed for characterizing engineered tissues such as collagen gels. In our study, OCT was used to image collagen gels with different seeding densities of smooth muscle cells (SMCs), including acellular gels, over a five-day period during which the gels contracted and became turbid with increased optical scattering. The gels were characterized quantitatively by their optical properties, specified by analysis of OCT data using a theoretical model. At 6 h, seeded cell density and scattering coefficient (mu(s)) were correlated, with mu(s) equal to 10.8 cm(-1)(10(6) cells mL). Seeded cell density and the scattering anisotropy (g) were uncorrelated. Over five days, the reflectivity in SMC gels gradually doubled with little change in optical attenuation, which indicated a decrease in g that increased backscatter, but only a small drop in mu(s). At five days, a subpopulation of sites on the gel showed substantially higher reflectivity (approximately a tenfold increase from the first 24 h). In summary, the increased turbidity of SMC gels that develops over time is due to a change in the structure of collagen, which affects g, and not simply due to a change in number density of collagen fibers due to contraction.

[1]  Y. Yang,et al.  Chitosan microchannel scaffolds for tendon tissue engineering characterized using optical coherence tomography. , 2007, Tissue engineering.

[2]  R. Tranquillo,et al.  ECM gene expression correlates with in vitro tissue growth and development in fibrin gel remodeled by neonatal smooth muscle cells. , 2003, Matrix biology : journal of the International Society for Matrix Biology.

[3]  Angelika Unterhuber,et al.  Three‐ and four‐dimensional visualization of cell migration using optical coherence tomography , 2009, Journal of biophotonics.

[4]  P M Pattany,et al.  High-resolution magnetic resonance imaging to characterize the geometry of fatigued porcine bioprosthetic heart valves. , 1997, The Journal of heart valve disease.

[5]  Chrysanthi Williams,et al.  Small-diameter artificial arteries engineered in vitro. , 2005, Circulation research.

[6]  T. B. Kirk,et al.  Confocal laser scanning microscopy in orthopaedic research. , 2005, Progress in Histochemistry and Cytochemistry.

[7]  Dirk J. Faber,et al.  Localized measurement of optical attenuation coefficients of atherosclerotic plaque constituents by quantitative optical coherence tomography , 2005, IEEE Transactions on Medical Imaging.

[8]  T Guda,et al.  A cellular perspective to bioceramic scaffolds for bone tissue engineering: the state of the art. , 2008, Current topics in medicinal chemistry.

[9]  A Rollins,et al.  In vivo video rate optical coherence tomography. , 1998, Optics express.

[10]  L. C. Henyey,et al.  Diffuse radiation in the Galaxy , 1940 .

[11]  Laura E Niklason,et al.  Requirements for growing tissue-engineered vascular grafts. , 2003, Cardiovascular pathology : the official journal of the Society for Cardiovascular Pathology.

[12]  R. Nerem,et al.  Altered response of vascular smooth muscle cells to exogenous biochemical stimulation in two- and three-dimensional culture. , 2003, Experimental cell research.

[13]  Ruikang K. Wang,et al.  Investigation of changes in optical attenuation of bone and neuronal cells in organ culture or three-dimensional constructs in vitro with optical coherence tomography: relevance to cytochrome oxidase monitoring , 2003, European Biophysics Journal.

[14]  Dietmar W Hutmacher,et al.  A comparison of micro CT with other techniques used in the characterization of scaffolds. , 2006, Biomaterials.

[15]  Zachary M. Eastman,et al.  Confocal mosaicing microscopy in Mohs skin excisions: feasibility of rapid surgical pathology. , 2008, Journal of biomedical optics.

[16]  W. Pearce,et al.  In situ localization and quantification of seventy-two-kilodalton type IV collagenase in aneurysmal, occlusive, and normal aorta. , 1995, Journal of vascular surgery.

[17]  Chenyang Xu,et al.  Characterization of atherosclerosis plaques by measuring both backscattering and attenuation coefficients in optical coherence tomography. , 2008, Journal of biomedical optics.

[18]  D. Leckband,et al.  Structural and functional optical imaging of three-dimensional engineered tissue development. , 2004, Tissue engineering.

[19]  Ruikang K. Wang,et al.  Investigation of optical coherence tomography as an imaging modality in tissue engineering , 2006, Physics in medicine and biology.

[20]  Steven L. Jacques,et al.  Low coherence interferometry of the cochlear partition , 2006, Hearing Research.

[21]  Tejal A Desai,et al.  Optical coherence tomography of cell dynamics in three-dimensional tissue models. , 2006, Optics express.

[22]  Erik Mosekilde,et al.  Phase-modulation laser interference microscopy: an advance in cell imaging and dynamics study. , 2008, Journal of biomedical optics.

[23]  P. Barber.  Absorption and scattering of light by small particles , 1984 .

[24]  Debby Gawlitta,et al.  Properties of engineered vascular constructs made from collagen, fibrin, and collagen-fibrin mixtures. , 2004, Biomaterials.

[25]  H. Yura,et al.  Analysis of optical coherence tomography systems based on the extended Huygens-Fresnel principle. , 2000, Journal of the Optical Society of America. A, Optics, image science, and vision.

[26]  R K Wang,et al.  The potential of optical coherence tomography in the engineering of living tissue. , 2004, Physics in medicine and biology.

[27]  David Levitz,et al.  Determination of optical scattering properties of highly-scattering media in optical coherence tomography images. , 2004, Optics express.