TV Guide Magazine has just released their Celebrity Guestbook with over 170 celebrity signatures, including those of the cast of The Big Bang Theory. The guestbook is now being actioned off to raise money for City of Hope.

The Big Bang Theory's Jim Parsons, Johnny Galecki, Kaley Cuoco, Simon Helberg, Kunal Nayyar and Mayim Bialik all signed the guest book. The autographed book also includes signatures from the casts of shows including Chuck, Community, Dexter and Dr Who. The guestbook was signed by over 170 stars aboard the TV Guide Magazine Yacht at Comic-Con 2011.

City of Hope is a not-for-profit hospital, research center and medical school recognized worldwide for its compassionate patient care, innovative science and translational research. Learn more at cityofhope.org.

The auction closes at 9pm on December 14. Visit auctionsforhope.org to place a bid.