Some biological characteristics of lipid conjugates of protein antigen that selectively induce delayed-type hypersensitivity in mice

Immunochemical studies of conjugates of isomaltosyl oligosaccharides to lipid. I. Antigenicity of the glycolipids and the production of specific antibodies in rabbits

Isomaltose oligosaccharides varying in size from two sugars, isomaltose (IM2), to seven sugars, isomaltohepatose (IM7), were coupled to stearylamine by reductive amination with sodium cyanoborohydride. Each compound was purified by column chromatography to yield a series of glycolipids containing oligosaccharides differing in length. Stearyl-isomaltotriose to stearyl-IM7 could be incorporated into liposomes and could render them agglutinable by specific antibodies to alpha 1 leads to 6 dextran and could be lysed if complement was also added, whereas those containing stearyl-IM2 were not agglutinated or lysed, indicating that stearyl-IM2 may not be protruding from the liposome surface sufficiently to react with the antibody. Stearyl-isomaltosyl oligosaccharides by themselves or incorporated into liposomes were equally antigenic when emulsified in complete Freund's adjuvant. They elicited pauciclonal responses, and the antibodies were alpha 1 leads to 6 specific, cross-reacted with dextran, and gave semirestricted isoelectric focusing patterns.

Lysolecithin analogs as adjuvants in delayed-type hypersensitivity in mice. I. Characterization of the adjuvant effect

The adjuvant activity of 5 different lysolecithin analogs (LLA) has been studied in delayed-type hypersensitivity (DTH) using fowl gamma globulin, bovine serum albumin and the terpolymer L-glutamic acid 60-L-alanine30-L-tyrosine10(GAT), as antigens. Increased DTH responses, by factors of 1.8--2.0 in CBA and BALB/c mice, showed that LLA are immunopotentiators if given intraperitoneally (i.p.) or subcutaneously (s.c.) together with the antigen. The concentration range, within which LLA are active, is limited to 10--20 micrograms/mouse s.c. and 100--300 micrograms/mouse i.p. Adjuvanticity was tested as a function of the LLA structure. The most pronounced immunopotentiation was obtained with racemic 1-octadecyl-2-methylglycero-3-phosphorylcholine (ET18-O-CH3). The LLA became less active with decreasing numbers of C atoms in the alkyl chain.