Cryopreservation modifies the distribution of the prostate-derived lectin SL15 on the llama (Lama glama) sperm

• Published in: Theriogenology Vol. 202; pp. 93 - 102
• Main Authors: Zampini, Renato, Castro-González, Ximena A., Scandura, Micaela, Sari, Luciana M., Diaz, Ana V., Martin, Alfredo, Argañaraz, Martin E., Apichela, Silvana A.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.05.2023
• Subjects: Animals; Camelids, New World; Cryopreservation; Cryopreservation - methods; Cryopreservation - veterinary; Lectins - metabolism; Male; Male reproductive system; New world camelids; Prostate; Semen - metabolism; Semen Preservation - methods; Semen Preservation - veterinary; Sperm; Sperm Motility; Spermatozoa - physiology; New world camelids; Sperm; Cryopreservation; Male reproductive system
• ISSN: 0093-691X; 1879-3231
• DOI: 10.1016/j.theriogenology.2023.03.006

Lectin-like molecules play a key role in mammalian sperm functionality. These multifunctional proteins have been proven to be involved in sperm capacitation, sperm motility, and viability, formation of the oviductal sperm reservoir, and in sperm-oocyte interaction. In a previous study, we reported the presence of a novel seminal plasma lectin, sperm lectin 15 kDa (SL15), adsorbed to the llama sperm. In order to gain knowledge in the understanding of SL15 and its functions, the aims of this study were to (a) elucidate the presence and localization of SL15 in the llama male reproductive tract and sperm, and (b) determine whether the sperm cryopreservation process of cooling and freeze-thawing affects the SL15 levels and distribution on llama sperm. We found that SL15 protein was expressed along the male reproductive system: testis, epididymis, prostate, and bulbourethral glands, being the prostate the main site of SL15 secretion. SL15 was localized on the sperm head, following different localization patterns. In order to understand if sperm cryopreservation induces modifications in the SL15 adsorption pattern, immunocytochemistry and flow cytometry analysis were carried out on fresh, 24 h cooled, and frozen-thawed sperm. Both cooled and frozen sperm showed particular SL15 patterns, that were not observed in the freshly ejaculated, indicating loss of SL15. Flow cytometry analysis also exhibited a decrease of SL15 in the cooled sperm (P < 0.05), whereas a tendency to decrease was found in frozen-thawed sperm (P < 0.1) when compared with freshly ejaculated sperm. This study extends the knowledge about the SL15 in the llama male physiology and provides evidence that cryopreservation-related techniques disrupt SL15 adsorption to the sperm membrane, possibly affecting sperm functionality and fertility. •The sperm lectin SL15 is mainly produced by the prostate.•SL15 is located mainly in the acrosomal region of llama ejaculated sperm.•Cooling and freezing processes modify the SL15 localization pattern of llama sperm.•Cooling causes a decrease of SL15 in llama sperm.