Identification of Pigment Epithelium-Derived Factor in the Interphotoreceptor Matrix of Bovine Eyes

Wu, Yan; Notario, Vicente; Gj, Chader; Becerra, S. Patricia

doi:10.1006/prep.1995.1060

Cited by 79 publications

(97 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Aqueous and vitreous extracts were obtained as described by Wu and Becerra (1996). IPM lavages were obtained after dissection of the anterior portion, removal of vitreous and retina (Wu et al, 1995), or alternatively, by cannulation (Pfeffer et al, 1983), a method known to assure an IPM lavage free of intracellular contamination maintaining the topological integrity of the IPM compartment (Adler, 1989).…”

Section: Tissue Samplesmentioning

confidence: 99%

“…The methods used have been described before by Wu et al (1995). Briefly, western transfers were immunoreacted with Ab-rPEDF with an enzymatic colorimetric method for detection.…”

Section: Western Blotting and Quantitation Of Pedf Proteinmentioning

confidence: 99%

“…To optimize a purification scheme for PEDF from monkey RPE conditioned media and vitreous extracts we modified previous methods for the purification of bovine PEDF (Wu et al, 1995;Wu and Becerra, 1996). These methods involved ammonium sulfate fractionation, cationexchange column chromatography and size-exclusion column chromatography.…”

Section: Pedf Protein Purificationmentioning

confidence: 99%

“…The protein was purified to near homogeneity by two purification steps. First, proteins were fractionated by S-Sepharose column chromatography as described (Wu et al, 1995). PEDFcontaining fractions were then pooled and subjected to sizeexclusion ultrafiltration using Centricon-100 to exclude large molecules and the filtrate applied to centricon-30 to exclude small molecules and concentrate the protein.…”

Section: Pedf Protein Purificationmentioning

confidence: 99%

“…These biological activities are of great importance for the development and maintenance of normal physiological functions in the eye. Biochemical and immunochemical studies have identified PEDF as a soluble extracellular protein localized in washes of the interphotoreceptor matrix (IPM), vitreous and aqueous of several mammalian species (Tombran-Tink et al, 1995;Wu et al, 1995;Ortego et al, 1996;Alberdi et al, 1998;Karakousis et al, 2001). PEDF, discovered as a product secreted by cultured RPE cells from fetal human eyes (Tombran Tink, 1991), can be released from a variety of cells, including stably transfected eukaryotic cells with full length PEDF cDNA under the control of recombinant transcriptional promoters (Stratikos et al, 1996;Perez-Mediavilla et al, 1998).…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Pigment epithelium-derived factor in the monkey retinal pigment epithelium and interphotoreceptor matrix: apical secretion and distribution

Becerra

Fariss

et al. 2004

Experimental Eye Research

111

View full text Add to dashboard Cite

Pigment epithelium-derived factor (PEDF) is an extracellular protein derived from the retinal pigment epithelium (RPE), a tissue formed by polarized cells that release growth and trophic factors in a directional fashion. We have investigated the distribution and directional release of PEDF protein by the monkey RPE. We established primary cultures of monkey RPE cells that expressed the PEDF gene, and that synthesized and secreted the PEDF protein. Northern analysis of RPE cultures and monkey ocular tissues showed that PEDF transcripts were highly expressed in RPE as compared with several other monkey ocular tissues, being even more abundant in cultured cells than they were in the native RPE. The differentiated RPE cells in culture secreted protein that shared the immunological, biochemical and biological characteristics of PEDF. The overall PEDF levels in the RPE conditioned media reached 6·5 mg ml 2 after 8 days in culture (i.e. 1·1 pg of PEDF per RPE cell). RPE cells were cultivated on permeable supports as monolayers forming a barrier between apical and basal compartments. Apical and basal culture media were sampled at three or four-day intervals for 18 cycles, and the PEDF content was quantified. Most of the PEDF protein was significantly higher in the apical than in the basal medium (. 4 times) at the initial recovery intervals, to be detected only in the apical medium at the latter intervals. In the native monkey eye, the concentration of soluble PEDF in the interphotoreceptor matrix (144 nM) was 7-fold and 25-fold greater than in vitreous and aqueous, respectively. PEDF was abundant in the interphotoreceptor matrix surrounding rod and cone outer segments, and was detectable at lower levels in the RPE as visualized by confocal microscopy. We concluded that PEDF synthesized by the RPE is secreted preferentially from the apical surface and is distributed apically to the RPE bordering the outer segments of photoreceptors. PEDF can be a useful marker for RPE polarization and differentiation. The polarization of RPE may be an important mechanism to control PEDF secretion and our results offer interesting possibilities on regulation of PEDF. q

show abstract

Section: Tissue Samplesmentioning

confidence: 99%

“…The methods used have been described before by Wu et al (1995). Briefly, western transfers were immunoreacted with Ab-rPEDF with an enzymatic colorimetric method for detection.…”

Section: Western Blotting and Quantitation Of Pedf Proteinmentioning

confidence: 99%

Section: Pedf Protein Purificationmentioning

confidence: 99%

Section: Pedf Protein Purificationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Pigment epithelium-derived factor in the monkey retinal pigment epithelium and interphotoreceptor matrix: apical secretion and distribution

Becerra

Fariss

et al. 2004

Experimental Eye Research

111

View full text Add to dashboard Cite

show abstract

Pigment epithelium-derived factor promotes the survival and differentiation of developing spinal motor neurons

et al. 1999

View full text Add to dashboard Cite

Pigment epithelium-derived factor (PEDF) has direct effects on the metabolism and proliferation of microglia and indirect effects on astrocytes

et al. 1997

View full text Add to dashboard Cite

Pigment epithelium-derived factor (PEDF), a neurotrophic agent first identified in conditioned medium from cultured human retinal pigment epithelial cells, induces neuronal differentiation with neurite outgrowth in Y-79 retinoblastoma cells and has a neurotrophic survival effect on cerebellar granule cells in culture. In the present study, we investigated the effects of human recombinant PEDF (rPEDF) on proliferation and activation of microglia and astrocytes isolated from newborn rat brain. rPEDF treatment caused microglia to round up morphologically, increased their metabolic activity (measured by both MTS conversion and acid phosphatase activity), but blocked proliferation (mitosis). This blocking effect could be demonstrated in cultures stimulated to proliferate by addition of granulocyte-macrophage colony stimulating factor. The effect of rPEDF on microglial metabolic activity showed a dose-response relationship both in serum-containing medium and in chemically defined medium and was blocked with anti-PEDF antibody. rPEDF had no direct effect on the metabolic activity or proliferation of cultured astrocytes but blocked their proliferation in astrocyte-microglia co-cultures. Proliferation of isolated astrocytes was also blocked by conditioned medium from microglia treated with PEDF (PMCM). The effect of PMCM on astrocytes was not blocked by an antibody to transforming growth factor-beta. These results demonstrate that PEDF activates microglial metabolism while blocking proliferation and suggest that a soluble factor(s) released by rPEDF-stimulated microglia blocks the proliferation of astrocytes. Thus, PEDF could play an important role in regulation of glial function and proliferation in the central nervous system.

show abstract

Identification of Pigment Epithelium-Derived Factor in the Interphotoreceptor Matrix of Bovine Eyes

Cited by 79 publications

References 0 publications

Pigment epithelium-derived factor in the monkey retinal pigment epithelium and interphotoreceptor matrix: apical secretion and distribution

Pigment epithelium-derived factor in the monkey retinal pigment epithelium and interphotoreceptor matrix: apical secretion and distribution

Pigment epithelium-derived factor promotes the survival and differentiation of developing spinal motor neurons

Pigment epithelium-derived factor (PEDF) has direct effects on the metabolism and proliferation of microglia and indirect effects on astrocytes

Contact Info

Product

Resources

About