The Poker Face singer attended The Foundation for AIDS Research benefit at Milk Studios in Los Angeles to pay tribute Glee creator Ryan Murphy, who was honoured in recognition of his career and his commitment to the fight against AIDS.

Gaga, who became close friends with Ryan when he cast her in TV show American Horror Story: Hotel, was joined by his other collaborators including Gwyneth Paltrow, who hosted the event, Lea Michele, the gala's co-chair, and Julia Roberts, who presented his award.

Sharon Stone conducted a live auction during the fundraiser, and Gaga splashed out $20,000 on the photo of Taylor making a rude hand gesture at the camera.

Cuba Gooding, Jr. reportedly lost a bidding war for a pair of diamond earrings with billionaire Barry Diller.

Gaga closed the gala by performing a hour-long set of jazz standards, including Nancy Sinatra's Bang Bang (My Baby Shot Me Down) and Frank Sinatra's Call Me Irresponsible.

"I love Ryan so much, and I'm so, so happy to be here," she said onstage. "He's really my friend and he's a wonderful person."

Other guests included Jamie Lee Curtis, Matt Bomer, Sarah Hyland and Rosie Huntington-Whiteley.

The evening raised $3.1 million (£1.9 million) for the charity, according to Ryan.