This T-shirt looks collectible. It's autographed, and I think it's the autograph of an outstanding person. But I'm not sure whose autograph it is. Does this belong to you, or did you just take a picture of it? Nevertheless, the T-shirt is very cool. Similar polo shirts I buy on wear-london.co.uk. By the way, not only T-shirts but also your entire wardrobe.
If you manage to find out whose autograph is still on this T-shirt, we will be happy if you share it with us. Still, curiosity takes its toll.