Activation and expansion of cells

A method for expanding a population of T-cells by cell surface moiety ligation, comprising:

• a. providing a population of cells wherein at least a portion thereof comprises T-cells;
• b. contacting said population of cells with a surface, wherein said surface has attached thereto a first agent that ligates a first cell surface moiety of a T-cell, and the same or a second surface has attached thereto a second agent that ligates a second moiety of said T-cell, wherein said ligation by the first and second agent induces proliferation of said T-cell;
• c. following contact with said surface for a period of time of about between 0 and 5 days, seeding said population of cells at a concentration of between about 0.2×106 and 5.0×106 cells/ml in a closed system comprising a disposable bioreactor bag comprising at least one inlet filter and one outlet filter;
• d. perfusing medium through said closed system at about 1 ml/minute;
• e. rocking said bioreactor bag on a rocking platform at about 5-15 rocks/minute;
• and wherein said T cells expand to a concentration of about between 6×106 cells/ml to about 90×106 cells/ml in less than about two weeks.