Unfixed as well as glutaraldehyde-fixed pelleted cells from pure cultures of Streptococcus mutans subspecies sobrinus (B13) were embedded in glycolme-thacrylate. Uitrathin were sections immunoperoxidase labelled with rabbit anti-S. mutans sobrinus γglobulin. It was found that unfixed specimens became labelled as precisely and as distinctly as did the fixed specimens. All controls were negative.
- Electron microscopy