The squad also features fellow Ireland stars Girvan Dempsey, Trevor Hogan, Shane Horgan, Bernard Jackman, Brian O'Driscoll and Leinster and Ireland's most-capped player Malcolm O'Kelly.
New Zealander David Holwell has also been included in the province's panel after signing a temporary contract to provide cover at out-half.
Almost 15,500 tickets have been sold for Saturday's game and tickets are still available on www.leinsterrugby.ie as well as from all Ticketmaster outlets.
Limited tickets are also on sale in Donnybrook from Spar and the Leinster Rugby Store. Supporters are advised to arrive early and use public transport.
Previewing the first of the two pool games against Castres, Leinster coach Michael Cheika said: "We've had some good interesting back-to-backs in Europe and, of course, we had Edinburgh last year where we beat them here and lost to them up there.
"I've learned - and I hope that I have learned well - so that we can be prepared over the coming two games.
"We want to play a certain way in all of the games in Europe, so it just happens that we play the same team two weeks in-a-row, and the same challenges that are there for us will be the same for them.
"We've got to manage our squad right, manage our tactics and above all manage our intensity.
"You've got to approach each of the six games like it's a Test match, or a cup final. If you can do that for six games then you're going to be prepared. But it's hard to do.
"We don't play Castres regularly, but we've watched a lot of videos and prepared ourselves the best we can."
LEINSTER Squad (v Castres Olympique): Backs (10) - Chris Keane, Chris Whitaker, David Holwell, Jonathan Sexton, Simon Keogh, Luke Fitzgerald, Brian O'Driscoll, Shane Horgan, Girvan Dempsey, Rob Kearney.
Forwards (14) - Cian Healy, Brian Blaney, Bernard Jackman, CJ Van Der Linde, Stan Wright, Trevor Hogan, Devin Toner, Malcolm O'Kelly, Rocky Elsom, Cameron Jowitt, Shane Jennings, Sean O'Brien, Jamie Heaslip, Stephen Keogh.