Effect of crude bacterial lipids on the course ofListeria infection in mice

Abstract

Crude lipids from 37 strains belonging to 32 bacterial species were isolated. By injecting mice with lipids 5 d prior to challenge with a virulent strain of Listeria monocytogenes, immunostimulatory activity in 19 preparations was found. In general, lipids of Gram-negative bacteria appeared to be more effective. As to bacilli, an extraordinary activity was found in the lipids of Bacillus firmus. Lipids of various species of the genus Listeria were found to be active in approximately one-half of cases. Among other Gram-positive bacteria, significant activity of lipids was found in Corynebacterium xerosis, Propionibacterium acnes and BCG. The composition of fatty acids in the lipids did not differ significantly from that reported in the literature and their mutual differences could not explain the different biological activity. In selected strains of Gram-negative bacteria lipids were repeatedly purified with anhydrous chloroform; these preparations were found to be inactive as compared with original chloroform-methanol lipids.

Immune response after adjuvant mucosal immunization of mice with inactivated influenza virus

“…Our studies of immuno-modulating properties of microorganisms revealed that the G+ bacterium B. firmus has pronounced immuno-stimulatory properties and, live or dead, it is harmless to mice in vivo; in addition, even high doses of inactivated bacterium do not suppress the viability of cells in culture [4][5][6][7][8]. Excellent adjuvant properties of this bacterium, which were proved in immunization of mice with ovalbumin via the respiratory tract [22] were confirmed in the intratracheal immunization of mice against type B influenza virus.…”

“…An extensive screening performed several years ago [4] showed that Bacillus firmus (BF), a non-pathogenic and non-toxigenic G+ bacterium of the environment, exceeds other G+ bacteria in its ability to stimulate anti-infectious immunity during experimental listeria infection in mice. Later, we showed stimulatory effects of BF on macrophage and lymphocyte activation in mice [5][6][7][8] and on anti-tumor activity in rats [9].…”

Effects of Bacillus firmus e volumine ex muris cellulae 6x on cytolytic activity of natural killer cells in vitro

“…Therefore, activation of NK cells might be an essential step in therapy, especially in cases of NK cell deficiency such as malignant diseases [40]. B. firmus, a nonpathogenic bacterium of the environment, possessed different immunomodulatory properties in vitro and in vivo [24][25][26][27][28][29], including immunostimulating effects on human [27] and murine B lymphocytes [25] and macrophages [28]. Furthermore, a study from Lomakova and colleagues showed the ability of inactivated B. firmus to activate murine peritoneal cells and enhanced production of several important immunomodulatory cytokines in vitro [41].…”

“…Bacillus (B.) firmus, a non-pathogenic and non-toxigenic gram-positive bacterium of the environment, possessed different immunomodulatory properties in vitro and in vivo [24][25][26][27][28][29]. B. firmus showed immunostimulating effects on human [27] and murine B lymphocytes [25] and macrophages [28].…”

Protective and cross-protective mucosal immunization of mice by influenza virus type A with bacterial adjuvant

“…The use of CT in humans is excluded because of its high toxicity; a number of LT mutants have been prepared that retain their adjuvant activity; these mutants were likewise tested on the mouse model and should not cause any serious side effect in humans [19]. Current studies aim at finding a suitable and safe mucosal adjuvant applicable in humans that could increase both mucosal and systemic immune response [20][21][22][23]. Such adjuvant is needed especially for immunization with subunit vaccines.…”