Quantum dot labeling and imaging of glial fibrillary acidic protein intermediate filaments and gliosis in the rat neural retina and dissociated astrocytes.
The use of antibody and peptide functionalized semiconductor quantum dots holds considerable potential for specific labeling of target antigens and high resolution optical imaging of biological preparations. Despite this potential, their use in neuroscience is not yet widespread; a number of technical and methodological challenges must still be overcome in order to produce reliable and reproducible labeling protocols. We have optimized and used anti-GFAP functionalized quantum dots for specific labeling of intermediate filaments in astrocyte and Müller glial cells in sections of intact rat neural sensory retina and dissociated primary spinal cord astrocytes. These techniques produced stable and robust imaging of retinal astrocytes and Müller cells with minimal non-specific background labeling and intense fluorescence resulting in a high signal to noise ratio. This resulted in clear and efficient labeling of normal levels of GFAP in the retina and the ability to differentiate it from pathologically high levels of GFAP associated with reactive gliosis in a laser induced injury model. Labeling and imaging of dissociated astrocytes demonstrated the presence of what appeared to be highly complex organizations of fine intermediate filaments that spanned between cells to form intricate networks of filamentous intercellular bridges. The presence of these structures in situ and in vivo as well as any potential functions remain to be determined, but their identification should be greatly facilitated by quantum dot labeling protocols.
Pathak
Smita
S
Materials Science and Engineering Graduate Program, University of California, San Diego 92037-0946, USA.
Tolentino
Rosa
R
Nguyen
Kim
K
D'Amico
Lorenzo
L
Barron
Erin
E
Cheng
Lingyun
L
Freeman
William R
WR
Silva
Gabriel A
GA
D000818:Animals; D001253:Astrocytes / Q000378:metabolism*; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism*; D045663:Quantum Dots; D051381:Rats; D012160:Retina / Q000166:cytology / Q000378:metabolism*
D005904:Glial Fibrillary Acidic Protein