Johnson (hip) was limited at Thursday's practice, Teresa Varley of the Steelers' official site reports.
Johnson practiced fully Wednesday, so his addition to the injury report Thursday is notable. That said, Brian Batko of the Pittsburgh Post-Gazette relays that the wideout, who is dealing with some soreness coming out of Week 4 action, indicates that he'll be available for Sunday's game against the Bills. Friday's final injury report will reveal whether Johnson heads into the weekend with an injury designation or fully cleared to play.