Fluorescent Immunohistochemistry: An Important Tool to Reveal Proteins From Tissues in Ancient Mummified Remains

During the restoration of the Saint Antonio Abate Cathedral in Castelsardo, Sardinia, Italy, numerous human remains were found in a crypt. The burial site contained upwards of 120 individuals organized in successive layers from the bottom of the crypt; of these, 18 partially mummified individuals have been identified, including the last 2 individuals buried in the crypt. In the present study, we focused on these 2 individuals by initially adopting a morphologic and anthropological approach. The anthropological analysis of the remains showed that the 2 bodies were partially mummified and that most of the organs were not available; for this reason, the sex was determined by secondary sexual characteristics of the skulls and the long bones. The aim of this research was to describe the general state of the mummified bodies and tissues by morphologic and ultrastructural analysis using light and electron microscopy techniques. To ensure the preservation of specific tissue proteins, immunohistochemical fluorescence analysis was used. Limited information is available regarding the preservation of mummified tissues. Thus, this study demonstrated the presence of muscle and skin tissue markers in a good state of preservation, even though the tissues had undergone a slow mummification process. Our results demonstrate that several types of tissues and cell proteins may survive over a prolonged period and that these materials survive the postmortem processes.