Screen stars Michael Urie, Leslie Bibb, Dot Jones, Pauley Perrette and Andrew Rannells also joined the 30,000 participants who took to the streets of West Hollywood and L.A. for the 28th annual fundraiser.
Partners star Bush took to her Twitter.com page to share snaps of the march, writing, "Had such a great morning at the Aids Walk La with Michael Urie. What a crowd! Honored to be a supporter."
Event founder Craig R. Miller adds, "The 30,000 participants who took to the streets today can take pride in the incredible $2,912,209 raised to fight Aids and lift up the lives of those affected by Hiv."
The $2.9 million generated will be handed to Aids education and prevention initiatives.