Robert Scibienski

Immunologic properties of protein-lipopolysaccharide complexes—III: Role of carbohydrate in the LPS adjuvant effect

Abstract Coupling of the protein antigen lysozyme to lipopolysaccharide (LPS) results in a complex which induces enhanced primary antilysozyme response and enhanced induction of immunological memory. The present experiments were performed to assess the role of the carbohydrate elements of LPS in this adjuvant effect. Periodate oxidized LPS, or LPS derived from an ‘O’ antigen deficient mutant, when used in the preparation of lysozyme-LPS complexes failed to yield complexes which induce enhanced primary antilysozyme responses. Carbohydrate deficiency had no effect on induction of immunological memory. This lack of enhancement of primary responsiveness was not due to any decrease in mitogenicity of the carbohydrate deficient LPS. The primary response adjuvanticity could be restored to complexes containing carbohydrate deficient LPS by secondarily coupling LPS derived carbohydrate elements to these complexes. These results imply that the carbohydrate component of LPS, and the ‘O’ antigen elements in particular, play a central role in enhancement of primary antibody responsiveness to a protein antigen coupled to that LPS.

Immunologic properties of protein-lipopolysaccharide complexes: IV. Circumventing suppression in immunologically tolerant animals

Abstract Mice which have been rendered immunologically tolerant to lysozyme by neonatal exposure to this antigen contain suppressor cells as demonstrated by cellular cotransfer experiments. Nevertheless these mice can be induced to respond to lysozyme by immunization with a lysozyme-lipopolysaccharide (LPS) complex. Such immunization results in a primary antibody response but not in induction of immunological memory. However, B-cell priming can be demonstrated in these animals. Similar induction of B-cell priming in normal animals is shown to be T-cell dependent, thus confirming earlier evidence that lysozyme-LPS is a thymus-dependent reagent. The possible mechanisms which underlie these findings are discussed.

Cellular parameters of the immunological memory induced by lysozyme-LPS mixtures and complexes.

The primary antibody response to the protein antigen lysozyme can be enhanced many fold by complexing the antigen with lipopolysaccharide (LPS). This complex, as well as lysozyme/LPS admixtures, is also capable of inducing a state of lysozyme specific immunological memory. Investigation of this memory state has revealed that administration of lysozyme either admixed or complexed with LPS results in priming of both B and T lymphocytes. Adoptive transfer of secondary responsiveness from animals primed in either fashion was further found to be T cell dependent. The implications of these findings are discussed.

Induction of latent immunological memory in genetically nonresponsive mice.

Abstract C57BL/10 mice exhibit major histocompatibility complex linked nonresponsiveness to hen egg white lysozyme (HEL). When these animals are primed with HEL in Freunds complete adjuvant (FCA), their secondary splenic plaque forming cell responses to aqueous HEL challenge are minimal to nonexistent. This notwithstanding, we show here that concomitant priming with both HEL and keyhole limpet hemocyanin (KLH) leads to an enhanced response to the HEL component following secondary challenge with an HEL-KLH conjugate. This enhancing effect can be transferred by nylon wool nonadherent spleen cells from HEL/FCA primed animals. Adoptive transfer studies with fractionated spleen cell populations suggest also that B cells are primed in these animals. Thus, animals which are incapable of mounting a secondary response to this antigen nevertheless appear to be primed at both the T-cell and B-cell levels following exposure to the antigen in FCA. The implications of this finding are discussed.

Response of Cba/N Mice to a Protein-Lipopolysaccharide Complex

The response of CBA/N mice to the lysozyme component of a lysozyme-LPS complex has been assessed. Primary responsiveness, memory induction and enhancement of the primary response by an allogeneic effect have been studied. Based on comparison with normal mice, only the primary response to the complex was affected by the xid trait. The observed defect was partially abrogated by an allogeneic effect.

Cellular Basis of Genetic Nonresponsiveness to Egg White Lysozyme

Abstract Utilizing radiation chimeras, we have investigated the cellular level at which the low immunological responsiveness to egg white lysozyme C57B1/10 mice is expressed. Both NR > F1 (responder) and F1 > NR combinations were assessed. The results demonstrate that C57B1/10 bone marrow can give rise to hen egg white lysozyme responsive cells, but this response requires that the antigen be presented by cells derived from high responder animals.