Vaccine adjuvants: Why and how

Abstract

Novel vaccine strategies include the so-called subunit vaccines, which encompass only the part of the pathogen to which immune recognition results in protection. The high purity of these vaccines make adverse events less likely, but it also makes the vaccines less immunogenic and therefore potentially less effective. Vaccine adjuvants that increase and modulate the immunogenicity of the vaccine are therefore added to solve this problem. Besides aluminum salts, which have been used in vaccines for 90 years, a number of novel vaccine adjuvants have been included in licensed vaccines over the last 30 years. Increasing insight into immunological mechanisms and how to manipulate them has replaced empirical with rational design of adjuvants, leading to vaccine adjuvants with increased and customized immunogenicity profiles without compromising vaccine safety.

Cricket paralysis virus internal ribosome entry site-derived RNA promotes conventional vaccine efficacy by enhancing a balanced Th1/Th2 response

“…Although inactivated and protein-based vaccines have long been used to prevent the spread of various pathogens [1] successfully, some of them elicit a weak immune response, short immune duration, and have several safety issues [2,3]. Therefore, research has focused on identifying antigen components responsible for immunogenicity in order to generate safer and more effective vaccines.…”

“…Therefore, research has focused on identifying antigen components responsible for immunogenicity in order to generate safer and more effective vaccines. However, purified recombinant antigens generally show poor immunogenicity [2]. To overcome this, immunostimulatory agents (i.e., adjuvants) are added to vaccines to induce robust immune responses against vaccine antigens [4][5][6].…”

Adjuvants in vaccines registered for human use

“…Sa istorijskog aspekta, mogu se razdvojiti četiri razdoblja u razvoju adjuvanasa: (1) inicijalni razvoj adjuvanasa za vakcine sa bakterijskim toksoidima u periodu između 1920. i 1940. godine; (2) šira upotreba ulja i aluminijuma kao adjuvanasa u periodu između 1940. i 1970. godine; (3) razvoj sintetskih adjuvanasa i depo sistema između 1970. i 1990. godine i (4) racionalni dizajn adjuvanasa koji aktiviraju urođeni imunski sistem od 1990. godine do danas (7). Tek početkom 1990-ih godina registrovane su vakcine, prvenstveno namenjene za primenu kod životinja, sa novim adjuvansima, koji pripadaju različitim klasama jedinjenja kao što su mineralne soli, produkti mikroorganizama, emulzije, saponini, citokini, polimeri, mikročestice i lipozomi (10,11). Dodavanje adjuvansa vakcinama ima za cilj da brže i jače indukuje zaštitni imunski odgovor kao i da smanji količinu antigena i broj imunizacija potrebnih da se postigne efikasan imunski odgovor (12).…”

Thrombin Enhances Ovalbumin-Specific Iga in Mucosal Surfaces by Intranasal Administration in Mice.

“…2 Although many kinds of vaccines are marketed, adjuvant-containing vaccines are limited (Christensen, 2016), and adjuvants that can induce IgA on mucosal surfaces are uncommon. It is well known that mucosal IgA plays a major role in protecting against infection by preventing pathogens from invading the body through the mucous membranes (Woof and Mestecky, 2005).…”