In a second study of vaccine therapy for B-cell lymphoma, the patient's tumor scFv was linked to the IgG2a and κ mouse immunoglobulin heavy-and light-chain constant regions chains, respectively. In this phase, I/II trial patients in remission after chemotherapy received two series of i.m. DNA vaccinations and at the end of the second vaccination, 50% of patients exhibited humoral and/or T-cell anti-Id responses; yet, these were cross-reactive with Id proteins from other patient's tumors. Subsequently, a third series of vaccinations was carried out using human GM-CSF DNA mixed with Id DNA: humoral or T-cell responses were boosted in some cases [56] .