Warriors centre Ben Te’o has been called up for England ahead of their opening NatWest 6 Nations game against Italy in Rome on Sunday 4 February (kick-off 3pm GMT).
Te’o has almost recovered from an ankle injury sustained back in October and is named in the 35-man squad.
The powerful centre who played two Tests for the British & Irish Lions last summer, will be looking to build on his eight caps for England, in which he has scored two tries.
Meanwhile, lock Will Spencer, who has been in impressive form for Warriors this season, is also being considered by England as he looks to overcome an ankle injury.
Spencer, who had a floating bone removed from his ankle recently, is due to return to action in approximately two to three weeks.
And the Warriors man is named among the unavailable players who could feature later on in the tournament – if and when they return from injuries and suspension.
Following this weekend’s club fixtures, 35 players will travel to Portugal for a week-long training camp before reconvening on Monday 29 January at Pennyhill Park ahead of the tournament opener.
England Head Coach Eddie Jones has selected eight uncapped players while there are 898 caps between the other 27 players in the squad.
Twenty-year-old Harlequins prop Lewis Boyce is called up for the first time following club teammate Joe Marler receiving a six-week suspension last week. The 2016 World Rugby Under 20 Championship winner is in his first season at the west London club having signed from Yorkshire Carnegie.
Gary Graham (Newcastle Falcons) is retained having been involved in the England set-up for the first time earlier this month in Brighton and Alec Hepburn (Exeter Chiefs) receives his first call-up into the senior squad.
Outside backs Nathan Earle (Saracens) and Harry Mallinder (Northampton Saints) are also named. Both travelled on England’s tour of Argentina in June but were not capped.
Eddie Jones said: “I have selected the strongest available squad to prepare for our opening match against Italy. It is important we start the tournament well and we will spend the next two weeks training smart and really fine-tuning our game-plan for the Italy match next month.
“I am expecting a really positive training camp in Portugal and while we have a few players unavailable through injury or suspension, it has provided opportunity for others who will be desperate to be involved in the Italy game.
“Jack Nowell is an option at 13, we have some great options there in Jonathan Joseph, Henry Slade and Ben Te’o.
“Ben Te’o has had good training at Worcester and hopefully he’ll have full training in Portugal and we can get him back on the field.”
England squad
Backs
Full-backs
Mike Brown (Harlequins)
Nathan Earle (Saracens) *
Harry Mallinder (Northampton Saints) *
Jonny May (Leicester Tigers)
Denny Solomona (Sale Sharks)
Anthony Watson (Bath Rugby)
Inside backs
Danny Care (Harlequins)
Owen Farrell (Saracens)
George Ford (Leicester Tigers)
Jonathan Joseph (Bath Rugby)
Alex Lozowski (Saracens)
Jack Nowell (Exeter Chiefs)
Henry Slade (Exeter Chiefs)
Ben Te’o (Worcester Warriors)
Marcus Smith (Harlequins) * **
Ben Youngs (Leicester Tigers)
Forwards
Back five
Gary Graham (Newcastle Falcons) *
Nick Isiekwe (Saracens)
Maro Itoje (Saracens)
George Kruis (Saracens)
Courtney Lawes (Northampton Saints)
Joe Launchbury (Wasps)
Zach Mercer (Bath Rugby) *
Chris Robshaw (Harlequins)
Sam Simmonds (Exeter Chiefs)
Sam Underhill (Bath Rugby)
Front row
Lewis Boyce (Harlequins) *
Dan Cole (Leicester Tigers)
Tom Dunn (Bath Rugby) *
Jamie George (Saracens)
Dylan Hartley (Northampton Saints)
Alec Hepburn (Exeter Chiefs) *
Kyle Sinckler (Harlequins)
Mako Vunipola (Saracens)
Harry Williams (Exeter Chiefs)
Players unavailable
Tom Curry (Sale Sharks)
Elliot Daly (Wasps)
Charlie Ewels (Bath Rugby)
Piers Francis (Northampton Saints)
Ellis Genge (Leicester Tigers)
James Haskell (Wasps)
Nathan Hughes (Wasps)
Joe Marler (Harlequins)
Matt Mullan (Wasps)
Beno Obano (Bath Rugby)
Semesa Rokoduguni (Bath Rugby)
Will Spencer (Worcester Warriors)
Billy Vunipola (Saracens)
Uncapped *
Apprentice player **