Brown was given a three-match ban after being sent off for kicking Barcelona’s Neymar during the second half of the 1-0 defeat against the Catalans on matchday two.
Brown automatically missed last week’s 2-1 win over Ajax, with Celtic unable to appeal the initial one-game ban.
The club have, however, contested the additional two matches, which would currently see the player miss the trip to Amsterdam next Wednesday and the home match with AC Milan on matchday five.
Brown will travel to Switzerland in person on Friday to plead his case at his appeal hearing. The cost to appeal the suspension to the club was £856.
Uefa’s control and disciplinary body imposed the additional two-match ban after reviewing footage of the incident, in which Brown was caught kicking out at Neymar as he lay on the ground after being fouled by the Celtic captain.
The appeals body can either uphold, amend or overturn the contested decision. If it feels there has been a mistrial, the case can be referred back to the first stage.
As Celtic were the only party to contest the decision – Uefa’s disciplinary inspector has not appealed the control and disciplinary body’s decision – the sanction cannot be increased.
Meanwhile, Parkhead striker Anthony Stokes has signed a new three-year deal with the club, while boss Lennon revealed talks are also underway with Georgios Samaras, Mikael Lustig and Joe Ledley.
Lennon said: "We have opened talks with Georgios's agent and we have already had a good chat with Joe's representatives.
"Mikael is another one we've started to talk to about a new deal. So far the signs are good from all of them and the feedback is positive.
"We aren't quite there by any means, but we're optimistic we can get something sorted out.
"These guys have been excellent for us. They have been hugely consistent and I think they are enjoying their football.
"There is a lot that we have to offer them, especially with the Champions League and so we'll see what happens over the next few weeks or so.
"Ideally, we'd like to get them tied up, but we'll see what happens."
More frustrating for Lennon is the fact there appears to be continual speculation about his players moving elsewhere.
Much of the latest exit talk centres on keeper Fraser Forster and, latterly, James Forrest.
Lennon says he feels there are constant moves to sell players from under his feet. He said:"It gets really annoying.
"You spend months planning and building a team, getting players settled and then you pick up a paper and there are stories with no substance in them.
"It feels as though there is always someone wanting to sell one of my players. It can get pretty tiresome, especially since there are a couple of months to go before the window even opens."