His family are hopeful of a recovery for the BBC Scotland football pundit.
They say they have received hundreds of supportive messages from across the football community.
MacLeod started his career with Partick Thistle and enjoyed success with Hibernian and Borussia Dortmund before playing more than 280 times in midfield for Celtic and receiving 20 caps with Scotland.
He went on to play for Dumbarton and Partick Thistle and managed both clubs.
MacLeod returned to Celtic as assistant manager under Wim Jansen, helping the club win a league and league cup double in their only season in charge.
He now has a career as a newspaper columnist and football pundit with BBC Scotland's Sportsound radio programme.
Source: BBC Sport
Source: BBC Sport