[The effects of haptenic presentation on B and T cell responses]

In this study the effect of haptenic presentation on the nature of immune response was investigated. Haptens (such as p-aminobenzoic acid, p-amino sulphanilic acid and p-aminoarsanilic acid) were coupled to an amino acid (tyrosine) alone, a protein (bovine serum albumine) a bacteria (M. tuberculosis) and injected to guinea pigs. Hapten specific humoral immune response was determined by either quantitative precipitin test or passive hemolysin test. Macrophage migration inhibition and skin tests were used for measurement of hapten specific cellular immunity. Hapten-tyrosine conjugates were found to be either non-immunogenic (PABA-Ti) or immunogenic only for T cells (PASA-Ti and PAAA-Ti). On the contrary, hapten-protein complexes induced anti-hapten antibodies, in the absence of cellular immunity to the hapten. Injection of hapten-bacteria conjugate in to animals caused a marked T cell responses to all haptens used, without or with minute amount of antibody. These results have suggested that it might be possible to direct an immune response towards a preferential humoral and cellular response by changing the way of presentation of a hapten.