Christina Applegate Sends Love to Selena Gomez: 'From One Immunocompromised to Another'

Jon Kopaloff/Getty; Steve Granitz/FilmMagic Christina Applegate and Selena Gomez

Christina Applegate is sharing the love with fellow immunocompromised celebrity Selena Gomez.

"To @selenagomez Am watching your documentary," Applegate wrote in a tweet. "From one immunocompromised to another. I'm here xo."

In her emotional new Apple TV+ documentary, 30-year-old Gomez opens up about mental health, lupus, and her ups and downs over the last six years of her life.

Applegate, 50, was diagnosed with multiple sclerosis in 2021 and has been open about her struggles with the disease.

"MS and Lulus are baby sisters from other mothers and a dad who owns a weird truck," Applegate wrote to Gomez. "Xo. Good on you kid for opening your life to those that need an eye open."

Both MS and lupus leave people with a weakened immune system leaving them extremely susceptible to infection.

AppleTV+ Selena Gomez

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In Gomez's documentary, directed by Alek Keshishian, the pop star and actress speaks openly about her physical and internal struggles.

From body image issues to painful lupus flare-ups and, of course, her ongoing journey with mental health, Gomez bravely invites fans into her life.

"I'm kind of scared. A lot of people are going to see this whole other side of me — and I'm like, 'I hope they like it,'" she told Kelly Clarkson earlier this month during an appearance on her talk show.

Applegate recently revealed that she's "never going to accept" being diagnosed with multiple sclerosis.

In an interview with The New York Times, the Anchorman star offered a candid perspective on the disease, and how it has affected her career.

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"There was the sense of, 'Well, let's get her some medicine so she can get better,'" Applegate said, regarding her initial diagnosis. "And there is no better. But it was good for me. I needed to process my loss of my life, my loss of that part of me. So I needed that time."

The actress was diagnosed in August 2021, while she was filming the third season of her Netflix dramedy Dead to Me, and the show halted production so that she could begin treatment. She now looks back at filming with MS with a mixture of emotions.

"It's not like I came on the other side of it, like, 'Woohoo, I'm totally fine,'" she told the Times. "Acceptance? No. I'm never going to accept this. I'm pissed."

RELATED VIDEO: Selena Gomez Says She May Not Be Able to Carry Children Due to Bipolar Disorder Meds, Details 2018 Psychosis

The Married ... With Children alum also shared that her appearance has changed since her diagnosis, and it is evident in the new season, which premieres Nov. 17.

"This is the first time anyone's going to see me the way I am," she said. "I put on 40 pounds; I can't walk without a cane. I want people to know that I am very aware of all of that."

If you or someone you know needs mental health help, text "STRENGTH" to the Crisis Text Line at 741-741 to be connected to a certified crisis counselor.