England midfielder David Beckham, who joined MLS side L.A. Galaxy last week, was presented to the crowd at half-time as part of the annual event aimed at boosting the profile of the league.
The MLS side should have taken the lead on the half-hour when U.S. international striker Eddie Johnson was brought down by Celtic's Scott Brown but Johnson's penalty kick was saved by Polish keeper Artur Boruc.
Former Aston Villa striker Angel, who plays for New York Red Bulls, opened the scoring six minutes later when he raced onto a defence-splitting
Angel's compatriot Toja reacted quickly to a De Rosario free-kick that hit the wall and drove home to make it 2-0 a minute before the break.
Scott McDonald had an effort disallowed for Celtic in the 53rd minute and then missed a couple of chances to bring the Glasgow side back into the game.
The MLS team, coached by ex-Scotland international and New England Revolution coach Steve Nicol, comfortably held on for the win.
(Reporting by Simon Evans in Miami)