Tolerance to lipopolysaccharide regulates apoptosis in B lymphocytes
© BioMed Central Ltd 2007
Published: 26 September 2007
The most important event determining sepsis evolution is immune system cell apoptosis, the immune cell elimination compromises the host effective response, and prevention of apoptosis events improve survival in sepsis models. Our objective was to identify whether lipopolysaccharide (LPS) tolerance regulates apoptotic genes and caspase pathway.
Materials and methods
Male Balb-C mice received LPS (1 mg/kg), a tolerant dose, and controls received 0.9% physiological serum during 5 days, both receiving on day 7 a LPS lethal dose (20 mg/kg). Control, 2 and 4 hours after lethal dose, IL-10, IL-6, IL-1β, TNFα and MIP2 were measured by ELISA. Splenic B lymphocytes were separated through magnetic beads and genes were analyzed by microarray, comparing control and tolerant groups. The tolerant and control groups were followed during 5 days to analyze survival.
Genic expression of apoptosis in tolerance to lipopolysaccharide
Genebank analysis number
TNF receptor-associated factor 4 (TRAF4)
Fas antigen ligand (FASL)
TNF-related apoptosis-inducing ligand (TRAIL)
Fas I receptor
Inhibitor of apoptosis protein 3
Caspase 2 precursor
Caspase 7, apoptosis-related cysteine protease
Caspase 2, apoptosis-related cysteine protease
Apoptotic protease activating factor 1
Fas-associated factor 1
Programmed cell death 1 protein precursor
Bid, apoptotic protease
Caspase 8, apoptosis-related cysteine protease
Tolerance was able to reduce cytokine plasma levels, immune cell apoptosis and mortality to LPS lethal doses.