The Jaguars sent cornerback C.J. Henderson and a third-round pick in the 2022 NFL Draft to the Panthers in exchange for Arnold and a fifth-round pick.
Henderson, 23, was the No. 9 overall pick in the 2020 NFL Draft. He started eight games in his rookie campaign, but missed the second half of the season due to a groin injury.
He totaled eight tackles and a tackle for a loss in two starts this season. He was inactive for the Jaguars' Week 3 loss to the Arizona Cardinals on Sunday in Jacksonville, Fla.
Arnold posted a career-high 438 yards on 31 catches in 16 games last season for the Cardinals. He signed a two-year, $6 million contract in free agency last off-season with he Panthers.
The four-year veteran totaled 84 yards on seven catches in three games this season with the Panthers.
Arnold was listed as the top tight end on the Panthers depth chart. Ian Thomas, Tommy Tremble and Colin Thompson are the other tight ends on the Panthers roster.
Arnold slides into the Jaguars' roster, which includes tight ends Chris Manhertz, James O'Shaughnessy, Luke Farrell and Jacob Hollister.
The Panthers roster now features Donte Jackson, Jaycee Horn, A.J. Bouye, Keith Taylor Jr., Stantley Thomas-Oliver III and Henderson at cornerback.
Horn sustained a broken foot in the Panthers' Week 3 win over the Houston Texans. He is expected to miss several months of action.
The Panthers (3-0) face the Dallas Cowboys at 1 p.m. EDT Sunday at AT&T Stadium in Arlington, Texas. The Jaguars (0-3) battle the Cincinnati Bengals at 8:20 p.m. EDT Thursday at Paul Brown Stadium in Cincinnati.