Liposome-based Freezing Medium Improves the Outcome of Mouse Prepubertal Testicular Tissue Cryopreservation

Abstract

Cryopreservation of testicular tissue holds an important role in the field of fertility preservation, particularly for prepubertal boys diagnosed with cancer. However, prepubertal testicular tissue cryopreservation is still considered to be in the experimental stage necessitating the refinement of cryopreservation protocol. Considering the fact that loss of membrane lipids is the primary cause of freeze–thaw-induced loss of testicular cell functions, in this study, we explored the beneficial properties of exogenous supplementation of membrane lipids in the form of liposomes in enhancing the cryosurvival of prepubertal testicular tissue. The freezing medium supplemented with liposomes (prepared from soy lecithin, phosphatidylethanolamine, phosphatidylserine, and cholesterol) was used for the experiments. Prepubertal testicular tissues from Swiss albino mice were cryopreserved in a liposome-containing freezing medium (LFM) composed of 0.25 mg/mL liposomes, 5% DMSO, and 30% FCS in the DMEM/F12 medium using a slow freezing protocol. The tissues were thawed and assessed for various testicular cell functions. Freezing in LFM mitigated the loss of viability, decreased malondialdehyde level (p < 0.05), and reduced apoptosis (p < 0.05) in the testicular cells compared to the testicular tissue cryopreserved in the control freezing medium (CFM). Further, DMSO (5%) appears to be the ideal penetrating cryoprotectant for prepubertal testicular tissue cryopreservation with liposome-based freezing medium. Similar enhancement in cryosurvival of cells was observed in adult human testicular tissue frozen with LFM. These findings highlight the translational value of liposome-based freezing medium in the cryopreservation of testicular tissue of prepubertal boys undergoing chemotherapy.