Bush has missed the last three games with a quad injury he sustained Oct. 17 in a loss to the Packers at Soldier Field. The sixth-year pro has appeared in six contests with two starts this year, recording 15 tackles on defense and four on special teams.
Coulter signed with the Bears Aug. 22, was waived during final cuts and then re-signed to the practice squad, where he spent the first 10 weeks of the season. He has appeared in one NFL regular-season game, playing six snaps on offense for the Texans Dec. 13, 2020 in a 36-7 loss to the Bears at Soldier Field.
Mack is the younger brother of Bears star outside linebacker Khalil Mack, who will undergo season-ending foot surgery next week. Ledarius signed with the Bears in 2020 as an undrafted free agent from Buffalo and has spent parts of his first two seasons on their practice squad.
In other news Saturday, the Bears downgraded running back Damien Williams to doubtful with a calf injury.
Ravens quarterback Lamar Jackson, meanwhile, was added to the injury report Saturday as questionable due to a non-COVID-19 illness. The sickness caused him to miss practice Wednesday and Thursday before he returned to work out without restrictions Friday.