@article {129, title = {Proteomic analysis of vitreous biopsy techniques.}, journal = {Retina}, volume = {32}, year = {2012}, month = {2012 Nov-Dec}, pages = {2141-9}, abstract = {

PURPOSE: To compare vitreous biopsy methods using analysis platforms used in proteomics biomarker discovery.

METHODS: Vitreous biopsies from 10 eyes were collected sequentially using a 23-gauge needle and a 23-gauge vitreous cutter instrument. Paired specimens were evaluated by UV absorbance spectroscopy, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and liquid chromatography tandem mass spectrometry (LC-MS/MS).

RESULTS: The total protein concentration obtained with a needle and vitrectomy instrument biopsy averaged 1.10 mg/mL (standard error of the mean = 0.35) and 1.13 mg/mL (standard error of the mean = 0.25), respectively. In eight eyes with low or medium viscidity, there was a very high correlation (R = 0.934) between the biopsy methods. When data from 2 eyes with high viscidity vitreous were included, the correlation was reduced (R = 0.704). The molecular weight protein sodium dodecyl sulfate-polyacrylamide gel electrophoresis profiles of paired needle and vitreous cutter samples were similar, except for a minority of pairs with single band intensity variance. Using LC-MS/MS, equivalent peptides were identified with similar frequencies (R \≥ 0.90) in paired samples.

CONCLUSION: Proteins and peptides collected from vitreous needle biopsies are nearly equivalent to those obtained from a vitreous cutter instrument. This study suggests both techniques may be used for most proteomic and biomarker discovery studies of vitreoretinal diseases, although a minority of proteins and peptides may differ in concentration.

}, keywords = {Adolescent, Aged, Biological Markers, Biopsy, Chromatography, Liquid, Electrophoresis, Polyacrylamide Gel, Eye Diseases, Eye Proteins, Female, Humans, Male, Middle Aged, Proteomics, Spectrophotometry, Ultraviolet, Tandem Mass Spectrometry, Vitrectomy, Vitreous Body, Young Adult}, author = {Skeie, Jessica M and Brown, Eric N and Martinez, Harryl D and Russell, Stephen R and Birkholz, Emily S and Folk, James C and Boldt, H Culver and Gehrs, Karen M and Stone, Edwin M and Wright, Michael E and Mahajan, Vinit B} }