[ROLE OF VARIOUS ANTIGENIC PREPARATIONS OF FRANCISELLA TULARENSIS IN FORMATION OF ALLERGY REACTION IN HUMANS AND...

Study the role of LPS in induction of anti-tularemia immunity in humans and animals.

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).

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.

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 antitularemia 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.