INTRANASAL ADMINISTRATION OF DIPHTHERIA TOXOID - SELECTING ANTIBODY ISOTYPES USING FORMULATIONS HAVING VARIOUS LIPOPHILIC CHARACTERISTICS

Non-ionic excipients, having different lipophilicity, were compared fo r their selection of immunological response in different organs and bi ological fluids. In order to express the lipophilicity of the formulat ion, the balance between the size and strength of the hydrophilic and lipophilic groups was used, called the hydrophile-lipophile balance (H LB) value. Mice were immunized and boosted intranasally with diphtheri a toroid, and samples were taken from the blood, spleen, nasal wash, l ungs, saliva, stomach, duodenum, jejunum and the skin. In general, for mulations which were highly hydrophilic and highly lipophilic were not able to augment the immunological response markedly (except for IgA). Formulations having intermediate HLB values, e.g. around 9.0, stimula ted both IgG(1) and IgG(2a) production, where the HLB = 5.5 formulatio n seemed to stimulate mainly IgG(2b) and IgG(3) antibody production. O n the other hand, comparing the IgA concentration in various samples w ith respective IgG level, increasing HLB value seems to augment the pr oduction of mainly IgA antibodies. The results indicate that the antib ody isotypes may be controlled, using variations in the hydrophile-lip ophile balance value.