How to respond?

I was in a 10+1 at party, early in the game with no reads. I was determined to play a tight game. I was wondering about how people think I should have played the following preflop situation (perhaps it is very easy but I am not sure):

Seat 1800)
Seat 3830)
Seat 4785)
Seat 5: hero (800)
Seat 72450)
Seat 8785)
Seat 9800)
Seat 10750)
Seat 4 posts small blind (10)
hero posts big blind (15)
** Dealing down cards **
Dealt to hero [ As, Kh ]
seat 7 folds.
seat 8 folds.
seat 9 folds.
seat 10 calls (15)
seat 1 folds.
seat 3 raises (55) to 55
seat 4 raises (85) to 95

hero?