Cytokine and cell adhesion molecule expression pattern in the gilthead seabream (Sparus aurata L.) testis
The gilthead seabream is a seasonally breeding protandrous hermaphrodite teleost, which develops asynchronous spermatogenesis during the male phase. During the second reproductive cycle the fish underwent a degenerative process accompanied by testicular acidophilic granulocyte infiltration, which started at post-spawning and which was enhanced at the testicular involution stage, prior to sex change. E-selectin, a cell adhesion molecule expressed by endothelial cells, and CCL4-like chemokine transcript levels increased in the spermatogenesis, post-spawning and testicular involution stages. The highest levels of interleukin-1b mRNA were observed at spermatogenesis, while the highest levels of tumour necrosis factor-α mRNA occurred during spawning and at the beginning of post-spawning. Finally, the mRNA levels of the transforming growth factor b1 peaked during post-spawning and spermatogenesis, but increased only gradually during the testicular involution stage.