Nemer was banned until the end of June after sending fellow prop Cherif Traore a rotten banana in club Benetton’s pre-Christmas “secret Santa” gift exchange.
The 24-year-old said he was “deeply sorry” for what he described as a moment of “stupidity”, and was ordered to complete a racism awareness course.
The prop has also been working on a migrants coaching programme run by the Italian federation.
Traore is not included in a 46-man group named by Kieran Crowley ahead of this autumn’s tournament in France.
Former England squad member Paolo Odogwu is an eye-catching potential debutant included in the squad, with the outside back appearing to commit his allegiance to Italy, who he qualifies for via his father.
The 26-year-old joined Stade Francais in October after Wasps entered administration.
Harlequins lock Dino Lamb, born in Warwickshire, is another uncapped inclusion in a group otherwise containing few surprises that will be narrowed to 33 ahead of the World Cup.
Monty Ioane, who missed the Six Nations due to club commitments with the Melbourne Rebels in Super Rugby Pacific, is in line to return, while number eight Toa Halafihi is also fit to return. Jake Polledri, however, has been ruled out due to another significant injury.
Italy will meet for three training camps in the Trentino town of Pergine Valsugana in June and July, before playing warm-up fixtures against Scotland, Ireland, Romania and Japan.
They begin their World Cup campaign against Nambia on 9 September and also face France, New Zealand and Uruguay in Pool A at the tournament.