Role of Various Antigenic Preparations of Francisella Tularensis in Formation of Allergy Reaction in Humans and Animals

Abstract

Aim. Study the role of LPS in induction of anti-tularemia immunity in humans and animals. Materials and methods. Activity of various antigenic preparations of tularemia microbe, including highly purified from protein and S- and R-LPS, was studied using leukocytolysis reaction with blood of vaccinated humans and guinea pigs and skin allergy test (guinea pigs). Results. Only the whole cells of Francisella tularensis, killed in protein non-denaturating conditions and conserving full S-LPS structure (tularin+) were shown to be inductors of delayed-type hypersensitivity reaction. Alterations in LPS structure (tularin) results in a significant decrease, and denaturation of bacterial proteins (during boiling) results in a complete loss of immune stimulating properties of the preparations. Purified LPS preparations and O-polysaccharide fraction of S-LPS are not able to activate cell-mediated immunity. Conclusion. The presence of LPS with the full structure affects the ability of antigenic preparations of F.tularensis to cause allergic reactions, and thus, form cell-mediated anti-tularemia immunity. LPS of F.tularensis can not be excluded as an adjuvant and provides the most effective presentation of epitopes of protein molecules for interaction with receptors of T-lymphocytes.