In vitro effects of an immunostimulating bacterial lysate on human lymphocyte function
Lanzilli, G.; Falchetti, R.; Tricarico, M.; Ungheri, D.; Fuggetta, M.P.
International Journal of Immunopathology and Pharmacology 18(2): 245-254
2005
ISSN/ISBN: 0394-6320 PMID: 15888247 Document Number: 590841
MLBL is an oral immunostimulating vaccine consisting of bacterial standardized lysates obtained by mechanical lysis of different strains of Gram-positive and Gram-negative bacteria that can cause acute and chronic infections of the respiratory tract. Previous studies suggested a stimulating effect of MLBL both on humoral and cellular immune responses. In the present study, the in vitro effects of MLBL on human lymphocyte effector functions and its mechanisms of action were evaluated. The results show that the most remarkable effects of MLBL on the immune system are: i) activation of the IL-2 receptor (IL2R alpha) on different lymphocyte subsets (B, CD4+T and CD8+T cells) involved both in humoral and cellular immune responses; ii) induction of cytokine synthesis (IL-2, IL-10, IL-12, IFN gamma) in the immune competent cells that induce and regulate immune responses; iii) generation of CD4+ and CD8+ effector T cells. Overall, these results suggest that the therapeutic effect of MLBL on acute and recurrent infections of the respiratory tract is related to its ability to activate the responses of different subsets of immune competent cells both for humoral and cellular immunity. Moreover, these effects can be induced either by direct immune cell activation or through the generation and activation of immune effector cells.