multi-level access for users and groups

Question
Is it possible to give access to a set of pages or posts to a specific group of users only

Here is the scenario
Group 1: user1 and user2
Group 2: user3 and user4
user 1 and 2 can post content which would need to be approved and published by user 5 (their manager)
user 3 and 4 can post content which would need to be approved and published by user 6 (their manager)
user 5 has access to page 1 and not page 2
user 6 has access to page 2 and not page 1