Northampton scrum-half Alex Mitchell, Harlequins number eight Alex Dombrandt and Northampton lock David Ribbans are among the 12 uncapped players named.
“Our preparation to build the team for the Italy game starts now,” Jones said.
“We’ll be slowly building up, working on the basics and working on team cohesion. We’re excited to be back together in camp representing England.”
Players from Exeter, Wasps, Bristol, Bath, Sale and Worcester are not included in Jones’ first training squad since the pandemic paused the 2020 Six Nations in March.
Sale’s game against Worcester has been moved to Wednesday after the club recorded 19 positive coronavirus cases but there are doubts it will go ahead.
If Sharks win that game, they will make it to the play-offs instead of Bath. Exeter, Wasps and Bristol have already secured their places in the semi-finals which take place on 10 and 11 October.
Another England training squad will be announced after that, with the team meeting again on 15 October.
Bristol and Exeter have European finals to play on 16 and 17 October respectively and the Premiership final takes place on 24 October.
England play Barbarians the next day and the week after will attempt to secure the Six Nations title against Italy.