NLCSH- 4 bet all in w/ 2nd pair?

[abcjnich]

200NL 100bb deep

Villain is extremely tight preflop. I don't have PT on my laptop,but looking at hand stats I have won 52% of hands PREFLOP over more than 100 hands. He has not shown down a single bluff all session, and he has not shown down a single slowplayed hand. Postflop, he is pretty tag, but he has 2 and 3 barrelled about as much as I have making me think he has to be bluffing some. So far he has not made shown down a single postturn bet with anything less than an overpair. OTB, when he doesn't fold, he usually raises with some calls.

the hand: he limps otb, I raise to 8 w/ A8o, he calls. Flop is Th8h2c. I lead for 12, he calls.
Turn (40): 5s, I bet 28, he raises to 72. I go all in.

Thoughts? My bet is for protection against semibluffs and bluffs. Anyone put him on a hand that beats me?