Adjuvants acquired immunity

Tritto E, Muzzi A, Pesce I, Monaci E, Nuti S, Galli G, Wack A, Rappuoli R, Hussell T, De Gregorio E (2007) The acquired immune response to the mucosal adjuvant LTK63 imprints the mouse lung with a protective signature. J Immunol 179(8) 5346-5357 Ulrich JT, Myers KR (1995) Monophosphoryl lipid A as an adjuvant. Past experiences and new directions. Pharm Biotechnol 6 495-524... 

Principally because of this latter reason, these pharmacologically active components of complement are attractive as molecular adjuvants. This is because their use has the potential of enhancing specific pathways of the innate and acquired immune processing and subsequent recognition of an Ag as opposed to the broader and less Ag-focused activation of the innate system in response to bacterial signals that come from of adjuvants derived from bacterial components. 

Dempsey PW, Allison MED, Akkai aju S, Goodnow CC, Feai on DT (1996) C3d of complement as a molecular adjuvant Bridging innate and acquired immunity. Science 271 348—350. 

As stated above, the principal objective for the use of an adjuvant in a vaccine is to potentiate immune response to an Ag of minimal immunogenicity. How this potentiation is achieved varies from adjuvant to adjuvant and in many cases, the precise mechanism of ac tion is unknov n. However, as a rule, immune potentiation is accomplished by the ability of the adjuvant to induce a variety of non-specific activities within the innate arm of the immune system. Once activated, the innate branch of immunity, particularly the complement system, orchestrates the various humoral and cell-mediated responses that operate within and between the innate and acquired arms. The result is a generalized activation and potentiation of the immune system in response to the adjuvant with the hope that this generalized immune priming will allow for a more effective processing and recognition of the Ag contained within the vaccine. 

Not only quantitative, but also qualitative changes of immune adjuvants were observed. Activated macrophages acquired new biological activities they were shown to modulate the activity of T-cells and to increase the number of T-lymphocytes in spleen (Toujas et al., 1975). In addition, they stimulated the activity of B-cells and inhibited the proliferation of tumor cells by a direct action on the immune system macrophages activate lymphocytes, which act as effector cells and kill target tumor cells by direct contact (Baum and Breeze, 1976). 

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