Anti-E. coli Beta Galactosidase Polyclonal antibody

Background Senescence-associated beta-galactosidase (SA-beta-GAL) histochemistry is the most commonly used biomarker of cellular senescence. These SA-beta-GAL-positive cells are senescent embryonic cells that are usually removed by apoptosis from the embryo, followed by macrophage-mediated clearance. Results Some authors have proposed that SA-beta-GAL activity in differentiated neurons from young and adult mammals cannot be uniquely attributed to cell senescence, whether in vivo or in vitro. Using the developing visual system of the chicken as a model, the present study found that SA-beta-GAL detected in the developing retina corresponded to lysosomal beta-galactosidase activity, and that SA-beta-GAL activity did not correlate with the chronotopographical distribution of apoptotic cells. However, SA-beta-GAL staining in the undifferentiated retina coincided with the appearance of early differentiating neurons. In the laminated retina, SA-beta-GAL staining was concentrated in the ganglion, amacrine, and horizontal cell layers. The photoreceptors and pigment epithelial cells also exhibited SA-beta-GAL activity throughout retinal development. We have also found that SA-beta-GAL staining strongly correlated p21 immunoreactivity. Conclusion In conclusion, the results clearly show that SA-beta-GAL activity cannot be regarded as a specific marker of senescence during retinal development, and that it is mainly expressed in subpopulations of postmitotic neurons, which are nonproliferative cells, even at early stages of cell differentiation.

Purpose We assessed whether mitomycin-C (MMC) has different antifibrotic mechanisms in trabeculectomy wound healing. Methods We identified 2 concentrations of MMC as "low-dose" by using WST-1 assay, Lactic dehydrogenase assay, and fluorescence-activated cell sorting flow cytometry. Senescence-associated beta-galactosidase (SA-beta-gal) and fibrotic gene expression was examined through immunocytochemistry, flow cytometry, real-time quantitative reverse transcription polymerase chain reaction, Western blotting, zymography, and modified scratch assay in vitro. In vivo, 0.1 mL of MMC or normal saline was injected to Tenon's capsule before trabeculectomy in a rabbit model. SA-beta-gal expression, apoptotic cell death, and collagen deposition in sites treated and not treated with MMC were evaluated using terminal dUTP nick end labeling assay and histochemical staining. Bleb function and intraocular pressure (IOP) levels were examined 3, 7, 14, 21, 28, and 35 days after trabeculectomy. Results In vitro, human Tenon's fibroblast (HTF) senescence was confirmed by observing cell morphologic change, SA-beta-gal accumulation, formation of senescence-associated heterochromatin, increased p16(INK4a)and p21(CIP1/WAF1)expression, lower percentage of Ki-67-positive cells, and decreased COL1A1 release. Increased expression of alpha-SMA,COL1A1, and Smad2 signaling in TGF-beta 1-induced stress fibers were passivated in senescent HTFs. In addition, cellular migration enhanced by TGF-beta 1was inactivated. In vivo, histological examination indicated increased SA-beta-gal accumulation, lower apoptosis ratios, and looser collagen deposition in sites treated with 0.2 mu M MMC. Low-dose MMC-induced cellular senescence prolonged trabeculectomy bleb survival and reduced IOP levels in a rabbit model. Conclusion Low-dose MMC-induced cellular senescence is involved in the antifibrotic mechanism of trabeculectomy wound healing.