Background: Early clinical trials of HER2/neu-derived peptide vaccines indicate that they may be useful for preventing recurrence in breast cancer patients rendered disease-free after standard-of-care therapy. An effective vaccination strategy will probably require stimulation of T helper (Th) cells. AE37 is an HER2/neu-derived peptide that has been modified to enhance antigen-specific stimulation of Th cells by linkage of the Ii-Key moiety of the MHC class II-associated invariant chain (Ii protein).
Objective: To review the literature regarding the role of a Th response in immunotherapy with a focus on this novel HER2/neu-derived AE37 peptide.
Results/conclusion: Improved immuno-genicity of the AE37 Ii-key hybrid peptide has been demonstrated in animal models, ex vivo patient cells, and, most recently, in a Phase I clinical trial in breast cancer patients. Future clinical trials incorporating AE37 into a peptide vaccine strategy are warranted.