Comparative expression of cell adhesion molecule1 (CADM1) in the testes of experimental mice and some farm animals

Cell adhesion molecule1 (CADM1) is a member of the immunoglobulin superfamily (IGSF) that has been found in mammalian testis and plays a substantial role in cell-to-cell interaction via either hemophilic (between spermatogenic cells) or heterophilic (between spermatogenic and somatic Sertoli cells) binding. The present study investigated the immunohistochemical localization of CADM1 in the testes of adult mice (Mus musculus), as well as sexually mature bull (Bos taurus), camel (Camelus dromedarius), and donkey (Equus asinus), using immunohistochemical techniques. The results revealed that CADM1 expression was observed in the spermatogonia and early spermatocytes as well as elongated spermatids in the mice testes; however, in the bull testis, its expression was restricted to the elongated spermatids. This expression was found in some of the early spermatocytes and elongated spermatids of the rutting camel testis but only found in the elongated spermatids of the non-rutting camel testis. Interestingly, CADM1 expression was detected in the spermatogonia, early spermatocytes, and elongated spermatids of the donkey testis. On the other hand, there was no expression of CADM1 observed in the Sertoli or interstitial cells. In conclusion, the expression of CADM1 during spermatogenesis differed among species and between rutting and non-rutting camel. Accordingly, this study emphasized the crucial role of CADM1 in the process of spermatogenesis and how it is related to sexual activity in both experimental and farm animals.