Figure 2.

A schematic drawing illustrating the restricted expression of different CT antigens in germ cells during spermatogenesis. The part on the right depicts different germ cell types during spermatogenesis, and the left part illustrates the unique expression patterns of seven different CT antigens in different germ cell types, illustrating their possible involvement in different phases of spermatogenesis. These CT antigens, besides their restricted expression in the testis but not other normal human cells/tissues, they are highly expressed in cancer cells. As such, many of these antigens are the targets of immunotherapy and vaccine development for cancer treatment. Yet their functional significance in the testis remains largely unexplored.