Table 1.

Mineral adjuvants and their properties.

Adjuvant type	Representing examples	General description	Mechanism of action	Advantages	Disadvantages
Mineral salts	Aluminum salts – aluminum hydroxide or aluminum phosphate	1.Licensed and approved by US FDA for human use 2.Misreferred as alum 3.It is widely used as human and veterinary vaccines 4.Aluminum hydroxide is more potent than aluminum phosphate due to their adsorption property 5.Considered as the safest adjuvant	1.Sort term depot effect 2.Induction of cytokine network 3.Complement activation 4.Delivery of antigens to different APC 5.Strong Th2 response	1.In expensive 2.Safe 3.Efficient uptake of alum adsorbed antigens by antigen presenting cells due to particulate nature with optimum size 4.Long lasting immune response when compared to soluble antigens	1.Not suitable for recombinant proteins and sub unit vaccines 2.Adverse effects have been reported such as inflammation and stimulate local production of erythema, granuloma, subcutaneous nodules, contact hypersensitivity and IgE mediated hypersensitivity. Alum cannot be frozen or lypholized 3.Unable to induce cytotoxic T cell response
	Calcium salts	1.Calcium salts in the form of Calcium phosphate have been used as human vaccine adjuvant especially DTP, polio, yellow fever and BCG vaccines 2.Approved for human use in European countries	1.Short term depot effect 2.Adsorbs soluble antigens and presents them in a particulate form to the immune system	It is a normal constituent of the body and therefore well tolerated, elicit high IgG type antibodies	1.It lacks immunomodulatory response 2.Neurological reactions have been observed 3.Local irritation and active inflammatory reaction at the site of injection