Improved method for obtaining 3-microns cryosections for immunocytochemistry.

The following describes a modified technique for obtaining 3-microns sections for light microscopic level immunocytochemistry. By combining 20% sucrose with Tissue-Tek OCT embedding compound in a ratio of 2:1, we produced a block that was suitable for cutting 3-microns sections on a conventional cryostat. The 3-microns sections were dramatically improved compared with 10-microns sections cut from tissue embedded in OCT alone, when viewed with both differential interference contrast microscopy (Nomarski optics) and indirect immunofluorescence. The method is simple, uses materials already available, and does not require training in a new technique.