Intralymphatic vaccination

Abstract

The immune response is initiated by dendritic cells and other antigen-presenting cells. These cells are present in nearly all organs and tissues of the body, so that theoretically any organ or tissue could serve as a route for vaccine administration. The choice of route is therefore mainly based on practical aspects. Using conventional needle and syringe the subcutaneous or intramuscular route are standard. The dermis and especially the epidermis are technically more difficult to target, but are likely to gain more interest due to the recent development of micro-needle patches and needle free injection devices. Vaccine administration via mucosal surfaces such as nasal or oral vaccination represents another option for needle free vaccine administration. While all the above mentioned routes of administration have been proven to work and protect against childhood diseases, influenza and many other infectious agents, the discussion and comparison of these different routes usually focuses on patient convenience, reduction of pain and distress for children, cost and on the possibility for mass vaccination. In this review, however, we would like to focus on how the route of administration can enhance the efficacy of vaccination, in clinical indications that are benefiting to a much lesser extent from conventional vaccination. Especially in therapeutic vaccination, i.e., in a smaller patient number that already suffers from a disease, vaccination efficiency rather than convenience is the main issue. This is particularly the case in therapeutic cancer vaccines and in allergen specific immunotherapy. Intralymphatic vaccination is a strategy to maximize immunogenicity and therefore vaccine efficacy. The main part of this review will discuss this long known vaccination route and its clinical applicability in therapeutic vaccination, with a special focus on gene vaccines.