Immunohistochemical localization of heat shock protein 27 in the retina of pigs

The expression of heat shock protein 27 (HSP27) was examined in the retinas of pigs. Western blot analysis detected the expression of HSP27 in the retinas of 1-day-old piglets and showed that it was enhanced in the retinas of 6-month-old adult pigs. Immunohistochemically, HSP27 immunostaining was seen mainly in ganglion cell bodies in the ganglion cell layer, and in some processes of astrocytes in the innermost nerve fiber layer. In 1-day-old piglets, HSP27 was detected weakly in the inner plexiform, inner nuclear cell, outer plexiform, and rod and cone layers. The HSP27 immunoreactivity across the retinal layers was enhanced in the retinas of 6-month-old pigs compared with newborn piglets. The HSP27 immunoreactivity in the radial processes of Müller cells was particularly prominent in adult pig retinas. In summary, this finding suggests that HSP27 plays an important role in signal transduction of glial cells and neuronal cells in the retina.