Effect of pH on the Elution of Model Antigens from Aluminum-Containing Adjuvants

Influence of Formulation pH and Suspension State on Freezing-Induced Agglomeration of Aluminum Adjuvants

“…The PZC for the Adjuphos TM was calculated to be 5.2 and the PZC for Alhydrogel TM was calculated to be 8.4. Notably, the measured PZC for Alhydrogel TM (PZC 8.4), Brenntag Biosector, is significantly different than that has previously been reported for Rehydragel (PZC 11.5), 7 Reheis, an aluminum hydroxide from a different manufacturer.…”

Selection of Adjuvants for Enhanced Vaccine Potency

“…The influence of pH on antigen adsorption can be complex because of the presence of multiple adsorption mechanisms, and differences in pH-dependent stability of antigens, and solubility of both antigens and aluminum salts [40]. Parabolic pH relationships were reported on lysozyme adsorption on aluminum phosphate (minimum at pH 4) [54] and ovalbumin (pI = 4.7) adsorption on aluminum hydroxide (maximum at pH 4.3-6.2) [55]. In rare cases, maximum adsorption can be found in a pH range, where antigens and aluminum salts carry the same charges [40].…”

Association Between Immunogenicity and Adsorption of a RecombinantStreptococcus pneumoniaeVaccine Antigen by an Aluminum Adjuvant

“…While the antigen-depot mechanism has previously been challenged because complete desorption of protein antigen by interstitial fluid may occur rapidly, 8 it is possible that adsorption prior to injection ensures a high localized concentration of antigen for an adequate, albeit brief, period of time to allow antigen uptake by antigen-presenting cells and dendritic cell activation. 13 In addition, the in vitro model of incubation with interstitial fluid might not mimic in vivo effects.…”

“…3 Vaccines containing aluminum prepared by either method have been administered to billions of people worldwide with relatively few reports of serious local reactions. 4 While many studies have attempted to explain the mechanism by which aluminum adjuvants bind to vaccine antigen, [5][6][7][8][9][10][11][12][13] the mechanism by which they potentiate the immune response is not well understood. The two mechanisms most commonly invoked for explaining adjuvantation are the depot effect and immunostimulation.…”