Lyophilization is suitable for storage and shipment of fresh tissue samples without altering RNA and protein levels stored at room temperature.

Lyophilization has been widely used for preservation, such as in food industry, pharmacy, biotechnology and tissues engineering, etc. However, there is no report on whether it could affect stability of RNA and protein levels in biological tissue samples. Herein we show that lyophilization can be used for storage of biological tissue samples without loss of bioactivities even stored at room temperature for 7-14 days. To address this issue, C57BL mouse tissues were prepared and dried by lyophilization and a baking method, respectively, followed by examination of morphological structure and total proteins by SDS-PAGE as well as gelatin zymography. Subsequently, the stability of RNAs and proteins, which were lyophilized and stored at room temperature (23°C) for 14 days was further examined by RT-PCR, SDS-PAGE and western blot. Results demonstrated that lyophilization did not alter total protein activities of various tissues, including enzyme activities, immunoreactivities and phosphorylation, and did not affect several RNAs in lyophilized tissues. Taken together, lyophilization may represent a valuable approach for preservation and long-distance shipment of biological samples, particularly for the international exchange of biological samples without altering their bioactivities.